map/src/app.js

import { drawMap } from "./renderer.js";
import { landuseLabel } from "./landuseCodes.js";
import { CELL_SIZE, MAP_H, MAP_W, worldIndexOf } from "./mapUtils.js";
import { clampCameraToWorld, createInitialCamera, createWorldMap, ensureWorldPaddingForCamera } from "./worldMap.js";
import { getViewportMap } from "./worldViewport.js";
import { PATCH_MIN_AREA, PATCH_MIN_HEIGHT, PATCH_MIN_WIDTH, buildPatchRects, validatePatchRect } from "./mapPatch.js";
import { collectTransferableBuffers } from "./transferUtils.js";

const modes = [
  ["all", "All"],
  ["terrain", "Terrain"],
  ["modern", "Modern"],
  ["history", "Premodern"],
  ["landuse", "Land Use"],
  ["admin", "Admin"],
];

const state = {
  seedText: "114514",
  generationType: "auto",
  mode: "all",
  toolMode: "pan",
  showFeatures: true,
  showLabels: true,
  showSeamDiagnostics: true,
  map: null,
  world: null,
  camera: { x: 0, y: 0 },
  viewportMap: null,
  viewWidth: MAP_W,
  viewHeight: MAP_H,
  hoverEntities: [],
  selectionRect: null,
  patchVariant: 0,
  zoom: 1,
  lastPatchResult: null,
  pendingPatch: null,
  patchBusy: false,
  patchBusyVariant: null,
  patchStatusMessage: "",
  renderRevision: 0,
  generationRuns: [],
  patchRuns: [],
  interactionRuns: [],
  diagnosticLog: [],
  diagnostics: {
    worldExpansionCount: 0,
    lastWorldExpansion: null,
    lastViewport: null,
    lastFeatureCounts: null,
    lastWorkerUsed: null,
    lastWorkerFallbackReason: null,
    lastPatchWorkerKind: null,
    lastGenerationWorkerUsed: null,
    lastGenerationWorkerFallbackReason: null,
  },
};

const canvas = document.getElementById("mapCanvas");
const canvasShell = document.querySelector(".canvas-shell");
const seedInput = document.getElementById("seed");
const generationTypeInput = document.getElementById("generationType");
const patchTerrainTypeInput = document.getElementById("patchTerrainType");
const patchModeInput = document.getElementById("patchMode");
const patchVariantInput = document.getElementById("patchVariant");
const generatePatchButton = document.getElementById("generatePatch");
const alternativePatchButton = document.getElementById("alternativePatch");
const patchStatusEl = document.getElementById("patchStatus");
const generateMapButton = document.getElementById("generateMap");
const randomSeedButton = document.getElementById("randomSeed");
const toolPanButton = document.getElementById("toolPan");
const toolPatchButton = document.getElementById("toolPatch");
const toolHintEl = document.getElementById("toolHint");
const zoomInButton = document.getElementById("zoomIn");
const zoomOutButton = document.getElementById("zoomOut");
const zoomResetButton = document.getElementById("zoomReset");
const centerMapButton = document.getElementById("centerMap");
const applyPatchButton = document.getElementById("applyPatch");
const discardPatchButton = document.getElementById("discardPatch");
const clearPatchSelectionButton = document.getElementById("clearPatchSelection");
const cancelPatchButton = document.getElementById("cancelPatchGeneration");
const showFeaturesInput = document.getElementById("showFeatures");
const showLabelsInput = document.getElementById("showLabels");
const showSeamDiagnosticsInput = document.getElementById("showSeamDiagnostics");
const modeGrid = document.getElementById("modeGrid");
const mainLegendGrid = document.getElementById("mainLegendGrid");
const floatingLegendGrid = document.getElementById("floatingLegendGrid");
const statsEl = document.getElementById("stats");
const advancedGenerationStatsEl = document.getElementById("advancedGenerationStats");
const advancedGenerationHistoryEl = document.getElementById("advancedGenerationHistory");
const advancedPatchStatsEl = document.getElementById("advancedPatchStats");
const advancedPatchHistoryEl = document.getElementById("advancedPatchHistory");
const advancedInteractionStatsEl = document.getElementById("advancedInteractionStats");
const advancedInteractionHistoryEl = document.getElementById("advancedInteractionHistory");
const advancedViewportDiagnosticsEl = document.getElementById("advancedViewportDiagnostics");
const advancedFeatureCountsEl = document.getElementById("advancedFeatureCounts");
const advancedPatchDiagnosticsEl = document.getElementById("advancedPatchDiagnostics");
const advancedSeamDiagnosticsEl = document.getElementById("advancedSeamDiagnostics");
const advancedWorkerDiagnosticsEl = document.getElementById("advancedWorkerDiagnostics");
const advancedWorldDiagnosticsEl = document.getElementById("advancedWorldDiagnostics");
const advancedWarningHistoryEl = document.getElementById("advancedWarningHistory");
const copyImportantDataButton = document.getElementById("copyImportantData");
const copyDebugStatusEl = document.getElementById("copyDebugStatus");
const tooltipEl = document.getElementById("mapTooltip");
const selectionSvgEl = document.getElementById("mapSelectionSvg");
const selectionEl = document.getElementById("mapSelection");
const progressEl = document.getElementById("generationProgress");
const progressStageEl = document.getElementById("generationProgressStage");
const progressTimingsEl = document.getElementById("generationProgressTimings");
let generationStartedAt = 0;
let generationCurrentStage = "";
let generationTimer = null;
let zoomRedrawRaf = null;
let zoomSettledTimer = null;
let zoomVisualState = null;
let zoomLatencyStartedAt = null;
let patchWorker = null;
let patchJobSeq = 0;
let patchRequestSeq = 0;
let activePatchCancel = null;
const PATCH_WORKER_INACTIVITY_WATCHDOG_MS = 60_000;
let generationWorker = null;
let generationJobSeq = 0;
let generationRequestSeq = 0;
const generationPendingJobs = new Map();

const dragState = {
  mode: null,
  pointerId: null,
  startClientX: 0,
  startClientY: 0,
  startCameraX: 0,
  startCameraY: 0,
  lastClientX: 0,
  lastClientY: 0,
  panRemainderX: 0,
  panRemainderY: 0,
  selectStart: null,
  selectEnd: null,
  selectPath: null,
  pendingCamera: null,
  panRaf: null,
  panLatencyStartedAt: null,
};

function displayWorld() {
  return state.pendingPatch?.world || state.world;
}

function displaySourceMap() {
  return displayWorld()?.sourceMap || state.map;
}

function activeMap() {
  return state.viewportMap || displaySourceMap();
}

function clampZoom(value) {
  const parsed = Number(value);
  if (!Number.isFinite(parsed)) return 1;
  return Math.min(Math.max(parsed, 0.55), 2.8);
}

function viewportSizeForZoom(zoom = state.zoom) {
  const z = clampZoom(zoom || 1);
  return {
    width: Math.max(1, Math.ceil(MAP_W / z)),
    height: Math.max(1, Math.ceil(MAP_H / z)),
  };
}

function clampCameraForView(camera, size = viewportSizeForZoom(state.zoom), world = displayWorld()) {
  return clampCameraToWorld(camera, world, size?.width || MAP_W, size?.height || MAP_H);
}

function syncViewportSize() {
  const size = viewportSizeForZoom(state.zoom);
  state.viewWidth = size.width;
  state.viewHeight = size.height;
  return size;
}

function canvasInteractionRect() {
  return zoomVisualState?.baseRect || canvas.getBoundingClientRect();
}

function mapCellScreenSize(map = activeMap()) {
  const rect = canvasInteractionRect();
  const mapWidth = Math.max(1, map?.width || state.viewWidth || MAP_W);
  return rect.width ? rect.width / mapWidth : CELL_SIZE * clampZoom(state.zoom || 1);
}

function applyCanvasZoom() {
  if (!canvas) return;
  state.zoom = clampZoom(state.zoom || 1);
  const baseWidth = MAP_W * CELL_SIZE;
  const baseHeight = MAP_H * CELL_SIZE;
  const shellRect = canvasShell?.getBoundingClientRect();
  const availableWidth = Math.max(160, (shellRect?.width || baseWidth) - 24);
  const availableHeight = Math.max(160, (shellRect?.height || baseHeight) - 24);
  const displayScale = Math.max(0.18, Math.min(availableWidth / baseWidth, availableHeight / baseHeight));
  canvas.style.width = `${Math.round(baseWidth * displayScale)}px`;
  canvas.style.height = `${Math.round(baseHeight * displayScale)}px`;
  syncSelectionSvgToCanvas();
  updateSelectionOverlayFromWorldRect();
}

function displayedCellSize() {
  return mapCellScreenSize();
}

function screenPointToMapPixel(clientX, clientY, sizeOverride = null) {
  const rect = canvasInteractionRect();
  if (!rect.width || !rect.height) return null;
  const map = activeMap();
  const viewWidth = Math.max(1, sizeOverride?.width || map?.width || state.viewWidth || MAP_W);
  const viewHeight = Math.max(1, sizeOverride?.height || map?.height || state.viewHeight || MAP_H);
  const canvasX = (clientX - rect.left) * ((canvas.width || MAP_W * CELL_SIZE) / rect.width);
  const canvasY = (clientY - rect.top) * ((canvas.height || MAP_H * CELL_SIZE) / rect.height);
  const cellX = canvasX / Math.max(1e-6, (canvas.width || MAP_W * CELL_SIZE) / viewWidth);
  const cellY = canvasY / Math.max(1e-6, (canvas.height || MAP_H * CELL_SIZE) / viewHeight);
  return { x: cellX * CELL_SIZE, y: cellY * CELL_SIZE };
}

function mapPixelToScreenPoint(px, py) {
  const rect = canvasInteractionRect();
  const map = activeMap();
  const viewWidth = Math.max(1, map?.width || state.viewWidth || MAP_W);
  const viewHeight = Math.max(1, map?.height || state.viewHeight || MAP_H);
  const canvasX = (px / CELL_SIZE) * ((canvas.width || MAP_W * CELL_SIZE) / viewWidth);
  const canvasY = (py / CELL_SIZE) * ((canvas.height || MAP_H * CELL_SIZE) / viewHeight);
  return {
    x: canvas.offsetLeft + canvasX * (rect.width / Math.max(1, canvas.width || MAP_W * CELL_SIZE)),
    y: canvas.offsetTop + canvasY * (rect.height / Math.max(1, canvas.height || MAP_H * CELL_SIZE)),
  };
}

function mapClientToCell(event, sizeOverride = null) {
  const map = activeMap();
  if (!map && !sizeOverride) return null;
  const p = screenPointToMapPixel(event.clientX, event.clientY, sizeOverride);
  if (!p) return null;
  return {
    x: Math.floor(p.x / CELL_SIZE),
    y: Math.floor(p.y / CELL_SIZE),
  };
}

function viewportCellToWorldCell(cell) {
  if (!cell || !state.camera) return null;
  return {
    x: Math.round(state.camera.x || 0) + cell.x,
    y: Math.round(state.camera.y || 0) + cell.y,
  };
}

function clampCanvasPoint(event) {
  const rect = canvasInteractionRect();
  return {
    x: Math.min(Math.max(event.clientX - rect.left, 0), rect.width),
    y: Math.min(Math.max(event.clientY - rect.top, 0), rect.height),
  };
}

function screenPointToWorldCell(point) {
  const map = activeMap();
  if (!map || !point) return null;
  const rect = canvasInteractionRect();
  if (!rect.width || !rect.height) return null;
  const viewWidth = Math.max(1, map.width || state.viewWidth || MAP_W);
  const viewHeight = Math.max(1, map.height || state.viewHeight || MAP_H);
  const canvasX = point.x * ((canvas.width || MAP_W * CELL_SIZE) / rect.width);
  const canvasY = point.y * ((canvas.height || MAP_H * CELL_SIZE) / rect.height);
  const localX = Math.floor((canvasX / Math.max(1e-6, (canvas.width || MAP_W * CELL_SIZE) / viewWidth)));
  const localY = Math.floor((canvasY / Math.max(1e-6, (canvas.height || MAP_H * CELL_SIZE) / viewHeight)));
  const cameraX = Math.round(state.camera?.x || 0);
  const cameraY = Math.round(state.camera?.y || 0);
  return {
    x: cameraX + Math.min(Math.max(localX, 0), Math.max(0, map.width - 1)),
    y: cameraY + Math.min(Math.max(localY, 0), Math.max(0, map.height - 1)),
  };
}

function worldCellToOverlayPoint(point) {
  const cameraX = Math.round(state.camera?.x || 0);
  const cameraY = Math.round(state.camera?.y || 0);
  const screen = mapPixelToScreenPoint((point.x - cameraX + 0.5) * CELL_SIZE, (point.y - cameraY + 0.5) * CELL_SIZE);
  return { x: screen.x - canvas.offsetLeft, y: screen.y - canvas.offsetTop };
}

function simplifySelectionPath(points) {
  const out = [];
  // Pointer sampling already suppresses sub-3 px jitter.  A second 6 px filter
  // turned curved lassos into long chords at low zoom, and those chords leaked
  // into terrain/administrative seams.  Keep a small adaptive tolerance instead.
  const minDistance = Math.max(1.5, Math.min(3, displayedCellSize() * 0.35));
  for (const p of points || []) {
    if (!out.length || Math.hypot(out[out.length - 1].x - p.x, out[out.length - 1].y - p.y) >= minDistance) out.push(p);
  }
  return out;
}

function polygonArea(points) {
  let area = 0;
  for (let i = 0; i < points.length; i++) {
    const a = points[i];
    const b = points[(i + 1) % points.length];
    area += a.x * b.y - b.x * a.y;
  }
  return Math.abs(area) * 0.5;
}

function selectionPathToShape(points) {
  const simplified = simplifySelectionPath(points || []);
  if (simplified.length < 3) return null;
  const polygon = [];
  for (const point of simplified.map(screenPointToWorldCell).filter(Boolean)) {
    const last = polygon[polygon.length - 1];
    if (!last || last.x !== point.x || last.y !== point.y) polygon.push(point);
  }
  if (polygon.length > 2 && polygon[0].x === polygon[polygon.length - 1].x && polygon[0].y === polygon[polygon.length - 1].y) polygon.pop();
  if (polygon.length < 3) return null;
  const xs = polygon.map((p) => p.x);
  const ys = polygon.map((p) => p.y);
  return {
    kind: "lasso",
    polygon,
    x0: Math.min(...xs),
    y0: Math.min(...ys),
    x1: Math.max(...xs) + 1,
    y1: Math.max(...ys) + 1,
    areaCells: Math.max(1, Math.round(polygonArea(polygon))),
  };
}

function syncSelectionSvgToCanvas() {
  if (!selectionSvgEl || !canvas) return null;
  const rect = canvas.getBoundingClientRect();
  const width = Math.max(1, rect.width || canvas.clientWidth || canvas.width || 1);
  const height = Math.max(1, rect.height || canvas.clientHeight || canvas.height || 1);
  selectionSvgEl.style.left = `${canvas.offsetLeft}px`;
  selectionSvgEl.style.top = `${canvas.offsetTop}px`;
  selectionSvgEl.style.width = `${width}px`;
  selectionSvgEl.style.height = `${height}px`;
  selectionSvgEl.setAttribute("width", String(width));
  selectionSvgEl.setAttribute("height", String(height));
  selectionSvgEl.setAttribute("viewBox", `0 0 ${width} ${height}`);
  return { width, height };
}

function drawSelectionSvg(points, invalid = false) {
  if (!selectionSvgEl) return;
  const bounds = syncSelectionSvgToCanvas();
  if (!bounds || !points || points.length < 3) {
    selectionSvgEl.style.display = "none";
    selectionSvgEl.innerHTML = "";
    return;
  }
  const pts = points.map((p) => {
    const x = Math.min(Math.max(p.x, 0), bounds.width);
    const y = Math.min(Math.max(p.y, 0), bounds.height);
    return `${x},${y}`;
  }).join(" ");
  selectionSvgEl.innerHTML = `<polygon points="${pts}" />`;
  selectionSvgEl.style.display = "block";
  selectionSvgEl.classList.toggle("invalid", !!invalid);
}

function hideSelectionSvg() {
  if (!selectionSvgEl) return;
  selectionSvgEl.style.display = "none";
  selectionSvgEl.innerHTML = "";
  selectionSvgEl.classList.remove("invalid");
}

function updateSelectionOverlay() {
  if (!dragState.selectPath?.length) return;
  const liveShape = selectionPathToShape(dragState.selectPath);
  const validation = validatePatchRect(liveShape, state.world);
  drawSelectionSvg(dragState.selectPath, !validation.ok);
  if (selectionEl) selectionEl.style.display = "none";
  if (generatePatchButton) generatePatchButton.disabled = true;
  if (alternativePatchButton) alternativePatchButton.disabled = true;
  if (patchStatusEl) {
    const current = validation.rect || liveShape;
    patchStatusEl.textContent = validation.ok
      ? `Selected: ${formatRectSize(validation.rect)}. Release to confirm patch selection.`
      : `${validation.reason} Current: ${formatRectSize(current)}.`;
    patchStatusEl.classList.toggle("invalid", !validation.ok);
  }
}

function updateSelectionOverlayFromWorldRect() {
  if (!state.selectionRect || !state.camera || !activeMap()) return;
  const rect = canvas.getBoundingClientRect();
  if (!rect.width || !rect.height) return;
  if (Array.isArray(state.selectionRect.polygon) && state.selectionRect.polygon.length >= 3) {
    const points = state.selectionRect.polygon.map(worldCellToOverlayPoint)
      .map((p) => ({ x: Math.min(Math.max(p.x, 0), rect.width), y: Math.min(Math.max(p.y, 0), rect.height) }));
    drawSelectionSvg(points, !validatePatchRect(state.selectionRect, state.world).ok);
    if (selectionEl) selectionEl.style.display = "none";
    return;
  }
  const cameraX = Math.round(state.camera.x || 0);
  const cameraY = Math.round(state.camera.y || 0);
  const p0 = mapPixelToScreenPoint((state.selectionRect.x0 - cameraX) * CELL_SIZE, (state.selectionRect.y0 - cameraY) * CELL_SIZE);
  const p1 = mapPixelToScreenPoint((state.selectionRect.x1 - cameraX) * CELL_SIZE, (state.selectionRect.y1 - cameraY) * CELL_SIZE);
  const vx0 = p0.x - canvas.offsetLeft;
  const vy0 = p0.y - canvas.offsetTop;
  const vx1 = p1.x - canvas.offsetLeft;
  const vy1 = p1.y - canvas.offsetTop;
  const x0 = Math.min(Math.max(Math.min(vx0, vx1), 0), rect.width);
  const y0 = Math.min(Math.max(Math.min(vy0, vy1), 0), rect.height);
  const x1 = Math.min(Math.max(Math.max(vx0, vx1), 0), rect.width);
  const y1 = Math.min(Math.max(Math.max(vy0, vy1), 0), rect.height);
  if (x1 - x0 < 1 || y1 - y0 < 1) {
    selectionEl.style.display = "none";
    return;
  }
  hideSelectionSvg();
  selectionEl.style.display = "block";
  selectionEl.style.left = `${canvas.offsetLeft + x0}px`;
  selectionEl.style.top = `${canvas.offsetTop + y0}px`;
  selectionEl.style.width = `${Math.max(1, x1 - x0)}px`;
  selectionEl.style.height = `${Math.max(1, y1 - y0)}px`;
  const validation = validatePatchRect(state.selectionRect, state.world);
  selectionEl.classList.toggle("invalid", !validation.ok);
}

function formatRectSize(rect) {
  if (!rect) return "-";
  const w = Math.max(0, rect.x1 - rect.x0);
  const h = Math.max(0, rect.y1 - rect.y0);
  const area = Math.max(0, rect.areaCells || (w * h));
  return `${w} x ${h} cells / ${area.toLocaleString()} cells`;
}

function normalizePatchVariant(value) {
  const parsed = Number.parseInt(value, 10);
  return Number.isFinite(parsed) ? Math.max(0, parsed) >>> 0 : 0;
}

function setPatchVariant(value, { update = true } = {}) {
  state.patchVariant = normalizePatchVariant(value);
  if (patchVariantInput && patchVariantInput.value !== String(state.patchVariant)) {
    patchVariantInput.value = String(state.patchVariant);
  }
  if (update) updatePatchControls();
  return state.patchVariant;
}

function readPatchVariant() {
  return setPatchVariant(patchVariantInput?.value ?? state.patchVariant, { update: false });
}

function resetPatchVariant({ update = true } = {}) {
  return setPatchVariant(0, { update });
}

function updatePatchControls() {
  const variant = readPatchVariant();
  const validation = validatePatchRect(state.selectionRect, state.world);
  const hasValidSelection = !!validation.ok;
  const hasPreview = !!state.pendingPatch;
  const busy = !!state.patchBusy;
  if (generatePatchButton) generatePatchButton.disabled = !hasValidSelection || busy;
  if (alternativePatchButton) alternativePatchButton.disabled = !hasValidSelection || busy;
  if (applyPatchButton) applyPatchButton.disabled = !hasPreview || busy;
  if (discardPatchButton) discardPatchButton.disabled = !hasPreview || busy;
  if (clearPatchSelectionButton) clearPatchSelectionButton.disabled = !state.selectionRect || busy;
  if (cancelPatchButton) cancelPatchButton.disabled = !busy;
  if (patchVariantInput) patchVariantInput.disabled = busy;
  if (!patchStatusEl) return;
  if (!state.selectionRect) {
    patchStatusEl.textContent = state.toolMode === "patch"
      ? `Right-drag a freeform patch area. Minimum: ${PATCH_MIN_WIDTH} x ${PATCH_MIN_HEIGHT} cells and ${PATCH_MIN_AREA.toLocaleString()} cells.`
      : "Right-drag on the map to draw a patch area.";
    patchStatusEl.classList.toggle("invalid", false);
    return;
  }
  if (!validation.ok) {
    patchStatusEl.textContent = `${validation.reason} Current: ${formatRectSize(validation.rect || state.selectionRect)}.`;
    patchStatusEl.classList.toggle("invalid", true);
    return;
  }
  const rects = buildPatchRects(validation.rect, state.world);
  const shownPatch = state.pendingPatch?.result || state.lastPatchResult;
  const candidateModeText = shownPatch?.patchGenerationMode || "";
  const delta = state.pendingPatch?.previewDelta || shownPatch?.previewDelta || null;
  const deltaText = delta
    ? ` Changed ${Number(delta.changedCells || 0).toLocaleString()} cells (${Number(delta.terrainChangedCells || 0).toLocaleString()} terrain / ${Number(delta.adminChangedCells || 0).toLocaleString()} admin).`
    : "";
  const previewText = state.pendingPatch
    ? ` Preview ready: ${shownPatch?.label || "candidate"}, variant ${shownPatch?.variant ?? variant}${candidateModeText ? `, ${candidateModeText}` : ""}.${deltaText} Use Apply Preview or Discard.`
    : shownPatch
      ? ` Last applied: ${shownPatch.label || "patch"}, variant ${shownPatch.variant ?? "-"}${candidateModeText ? `, ${candidateModeText}` : ""}.`
      : "";
  const busyText = state.patchBusy
    ? ` Generating variant ${state.patchBusyVariant ?? variant}; the currently displayed map will be replaced only after a verified preview is rendered.`
    : "";
  const statusText = state.patchStatusMessage ? ` ${state.patchStatusMessage}` : "";
  patchStatusEl.textContent = `Selection: ${formatRectSize(validation.rect)}. Core ${formatRectSize(rects.coreRect)} / write ${formatRectSize(rects.writeRect)}.${previewText}${busyText}${statusText}`;
  patchStatusEl.classList.toggle("invalid", false);
}

function setToolMode(mode) {
  state.toolMode = mode === "patch" ? "patch" : "pan";
  toolPanButton?.classList.toggle("active", state.toolMode === "pan");
  toolPatchButton?.classList.toggle("active", state.toolMode === "patch");
  toolHintEl?.classList.toggle("hidden", state.toolMode !== "patch");
  canvasShell?.classList.toggle("patch-intent", state.toolMode === "patch");
  updatePatchControls();
}

function setZoomKeepingCenter(nextZoom) {
  const startedAt = performance.now();
  const renderWorld = displayWorld();
  if (!renderWorld) return;
  const oldSize = viewportSizeForZoom(state.zoom);
  const centerWorld = {
    x: Math.round((state.camera?.x || 0) + oldSize.width / 2),
    y: Math.round((state.camera?.y || 0) + oldSize.height / 2),
  };
  state.zoom = clampZoom(nextZoom);
  const nextSize = syncViewportSize();
  state.camera = clampCameraForView({
    x: Math.round(centerWorld.x - nextSize.width / 2),
    y: Math.round(centerWorld.y - nextSize.height / 2),
  }, nextSize, renderWorld);
  redraw({ fastTerrain: false, allowWorldExpand: false });
  recordInteractionLatency("zoom button", startedAt, { zoom: state.zoom });
}

function recenterMap() {
  const renderWorld = displayWorld();
  if (!renderWorld) return;
  state.camera = createInitialCamera(renderWorld);
  redraw({ fastTerrain: false, allowWorldExpand: false });
}

function clearDragMode() {
  dragState.mode = null;
  dragState.pointerId = null;
  dragState.pendingCamera = null;
  dragState.panRemainderX = 0;
  dragState.panRemainderY = 0;
  if (dragState.panRaf != null) {
    cancelAnimationFrame(dragState.panRaf);
    dragState.panRaf = null;
  }
  dragState.panLatencyStartedAt = null;
  canvasShell?.classList.remove("panning", "selecting");
}

function schedulePanRedraw(camera) {
  dragState.pendingCamera = camera;
  if (!dragState.panLatencyStartedAt) dragState.panLatencyStartedAt = performance.now();
  if (dragState.panRaf != null) return;
  dragState.panRaf = requestAnimationFrame(() => {
    dragState.panRaf = null;
    if (!dragState.pendingCamera) return;
    const next = dragState.pendingCamera;
    dragState.pendingCamera = null;
    if (next.x === state.camera.x && next.y === state.camera.y) return;
    const startedAt = dragState.panLatencyStartedAt || performance.now();
    dragState.panLatencyStartedAt = null;
    state.camera = next;
    // Do not auto-expand the backing world while a pointer drag is active.
    // Expansion shifts world coordinates; doing it mid-drag invalidates the
    // pointer-to-camera baseline and can make the viewport appear to jump.
    redraw({ fastTerrain: true, allowWorldExpand: false });
    recordInteractionLatency("pan", startedAt, { zoom: state.zoom, fast: true });
  });
}

function commitPendingPatch({ redrawAfter = true } = {}) {
  if (!state.pendingPatch?.world) return false;
  state.world = state.pendingPatch.world;
  state.map = state.world.sourceMap || state.map;
  state.lastPatchResult = state.pendingPatch.result || state.world.lastPatchResult || state.lastPatchResult;
  state.pendingPatch = null;
  state.patchStatusMessage = "";
  state.viewportMap = null;
  if (redrawAfter) {
    renderStats(displaySourceMap());
    redraw({ fastTerrain: true, allowWorldExpand: false });
    window.setTimeout(() => redraw({ fastTerrain: false, allowWorldExpand: false }), 80);
  }
  return true;
}

function discardPendingPatch({ redrawAfter = true } = {}) {
  if (!state.pendingPatch) return false;
  state.pendingPatch = null;
  state.patchStatusMessage = "";
  state.viewportMap = null;
  if (redrawAfter) {
    renderStats(displaySourceMap());
    redraw({ fastTerrain: false, allowWorldExpand: false });
  }
  return true;
}

function hideSelectionOverlay(options = {}) {
  const commitPreview = options.commitPreview === true;
  const discardPreview = options.discardPreview === true || (!commitPreview && options.keepPreview !== true && !!state.pendingPatch);
  if (commitPreview) commitPendingPatch({ redrawAfter: false });
  else if (discardPreview) discardPendingPatch({ redrawAfter: false });
  dragState.selectStart = null;
  dragState.selectEnd = null;
  dragState.selectPath = null;
  state.selectionRect = null;
  resetPatchVariant({ update: false });
  hideSelectionSvg();
  if (selectionEl) selectionEl.style.display = "none";
  state.viewportMap = null;
  renderStats(displaySourceMap());
  updatePatchControls();
  if (commitPreview || discardPreview) redraw({ fastTerrain: false, allowWorldExpand: false });
}

function selectionPixelsToCells(start, end) {
  const a = screenPointToWorldCell(start);
  const b = screenPointToWorldCell(end);
  if (!a || !b) return null;
  return {
    x0: Math.min(a.x, b.x),
    y0: Math.min(a.y, b.y),
    x1: Math.max(a.x, b.x) + 1,
    y1: Math.max(a.y, b.y) + 1,
  };
}

function selectionPixelsToShape(start, end, path = null) {
  if (Array.isArray(path) && path.length >= 3) return selectionPathToShape(path);
  return selectionPixelsToCells(start, end);
}

function handleMapPointerDown(event) {
  if (!state.world || !canvasShell) return;
  if (event.button !== 0 && event.button !== 2) return;
  dragState.pointerId = event.pointerId;
  dragState.startClientX = event.clientX;
  dragState.startClientY = event.clientY;
  dragState.startCameraX = state.camera.x;
  dragState.startCameraY = state.camera.y;
  dragState.lastClientX = event.clientX;
  dragState.lastClientY = event.clientY;
  dragState.panRemainderX = 0;
  dragState.panRemainderY = 0;
  tooltipEl?.classList.remove("visible");

  if (event.button === 0) {
    dragState.mode = "pan";
    canvasShell.classList.add("panning");
  } else {
    if (state.toolMode !== "patch") setToolMode("patch");
    if (state.pendingPatch) discardPendingPatch({ redrawAfter: false });
    state.selectionRect = null;
    hideSelectionSvg();
    if (selectionEl) selectionEl.style.display = "none";
    dragState.mode = "select";
    dragState.selectStart = clampCanvasPoint(event);
    dragState.selectEnd = dragState.selectStart;
    dragState.selectPath = [dragState.selectStart];
    canvasShell.classList.add("selecting");
    updateSelectionOverlay();
  }

  canvas.setPointerCapture?.(event.pointerId);
  event.preventDefault();
}

function handleMapPointerMove(event) {
  if (!dragState.mode || dragState.pointerId !== event.pointerId || !canvasShell) return;
  tooltipEl?.classList.remove("visible");

  if (dragState.mode === "pan") {
    const rect = canvas.getBoundingClientRect();
    const maxDeltaX = Math.max(320, rect.width * 0.72);
    const maxDeltaY = Math.max(240, rect.height * 0.72);
    const rawDx = event.clientX - dragState.lastClientX;
    const rawDy = event.clientY - dragState.lastClientY;
    dragState.lastClientX = event.clientX;
    dragState.lastClientY = event.clientY;

    // Pointer capture can occasionally deliver a stale/outlier coordinate after
    // a tab switch, resize, context-menu gesture, or OS-level event hiccup.  A
    // single implausibly large delta would otherwise become a large camera jump.
    if (Math.abs(rawDx) <= maxDeltaX && Math.abs(rawDy) <= maxDeltaY) {
      const cellSize = Math.max(1, displayedCellSize());
      const totalX = dragState.panRemainderX + rawDx / cellSize;
      const totalY = dragState.panRemainderY + rawDy / cellSize;
      const dxCells = totalX < 0 ? Math.ceil(totalX) : Math.floor(totalX);
      const dyCells = totalY < 0 ? Math.ceil(totalY) : Math.floor(totalY);
      dragState.panRemainderX = totalX - dxCells;
      dragState.panRemainderY = totalY - dyCells;
      if (dxCells || dyCells) {
        const base = dragState.pendingCamera || state.camera;
        const nextCamera = clampCameraForView({
          x: base.x - dxCells,
          y: base.y - dyCells,
        }, viewportSizeForZoom(state.zoom));
        schedulePanRedraw(nextCamera);
      }
    }
  } else if (dragState.mode === "select") {
    dragState.selectEnd = clampCanvasPoint(event);
    if (!dragState.selectPath || Math.hypot(dragState.selectEnd.x - dragState.selectPath[dragState.selectPath.length - 1].x, dragState.selectEnd.y - dragState.selectPath[dragState.selectPath.length - 1].y) >= 3) {
      dragState.selectPath = [...(dragState.selectPath || []), dragState.selectEnd];
    }
    updateSelectionOverlay();
  }

  event.preventDefault();
}

function handleMapPointerUp(event) {
  if (dragState.pointerId !== event.pointerId) return;
  const wasPanning = dragState.mode === "pan";
  if (dragState.mode === "select") {
    dragState.selectEnd = clampCanvasPoint(event);
    if (!dragState.selectPath || dragState.selectPath.length < 2) dragState.selectPath = [dragState.selectStart, dragState.selectEnd];
    else dragState.selectPath = [...dragState.selectPath, dragState.selectEnd];
    const shape = selectionPixelsToShape(dragState.selectStart, dragState.selectEnd, dragState.selectPath);
    const width = Math.abs(dragState.selectEnd.x - dragState.selectStart.x);
    const height = Math.abs(dragState.selectEnd.y - dragState.selectStart.y);
    if (shape && (dragState.selectPath.length >= 3 || (width >= 4 && height >= 4))) {
      state.selectionRect = shape;
      state.lastPatchResult = null;
      state.patchStatusMessage = "";
      resetPatchVariant({ update: false });
      updateSelectionOverlayFromWorldRect();
      updatePatchControls();
    } else {
      hideSelectionOverlay();
    }
  }
  canvas.releasePointerCapture?.(event.pointerId);
  if (wasPanning && dragState.pendingCamera) {
    state.camera = dragState.pendingCamera;
    dragState.pendingCamera = null;
  }
  clearDragMode();
  if (wasPanning) {
    const startedAt = performance.now();
    redraw({ fastTerrain: false });
    recordInteractionLatency("pan settle", startedAt, { zoom: state.zoom, fast: false });
  }
  event.preventDefault();
}

function parseSeed(seedText) {
  const numeric = Number.parseInt(seedText, 10);
  if (Number.isFinite(numeric)) return numeric >>> 0;

  let hash = 2166136261;
  for (const ch of seedText) hash = Math.imul(hash ^ ch.charCodeAt(0), 16777619);
  return hash >>> 0;
}

function formatMs(ms) {
  if (!Number.isFinite(ms)) return "-";
  return ms >= 1000 ? `${(ms / 1000).toFixed(2)}s` : `${Math.round(ms)}ms`;
}

function formatSeconds(value, digits = 4) {
  if (!Number.isFinite(value)) return "-";
  return `${value.toFixed(digits)}s`;
}

function pushCapped(history, item, limit = 10) {
  history.unshift(item);
  if (history.length > limit) history.length = limit;
}

function countTruthyCells(mask) {
  if (!mask || typeof mask.length !== "number") return 0;
  let count = 0;
  for (let i = 0; i < mask.length; i++) if (mask[i]) count++;
  return count;
}

function mapAreaCells(map) {
  if (!map) return MAP_W * MAP_H;
  const focusedArea = countTruthyCells(map.focusedPrefectureMask || map.prefectureMask || map.humanRegionMask);
  if (focusedArea > 0) return focusedArea;
  return Math.max(1, (map.width || MAP_W) * (map.height || MAP_H));
}

function formatAreaCells(cells) {
  return `${Math.max(0, Math.round(cells || 0)).toLocaleString()} cells`;
}

function rectAreaCells(rect) {
  if (!rect) return 0;
  return Math.max(0, Math.round((rect.x1 - rect.x0) * (rect.y1 - rect.y0)));
}

function terrainTypeLabel(value) {
  const option = generationTypeInput ? Array.from(generationTypeInput.options).find((item) => item.value === value) : null;
  return option?.textContent || value || "Auto";
}

function secondsPerThousandCells(totalMs, areaCells) {
  const area = Math.max(1, areaCells || 0);
  return (totalMs || 0) / area;
}

function numericValues(items, selector) {
  return (items || [])
    .map(selector)
    .map(Number)
    .filter((value) => Number.isFinite(value) && value >= 0);
}

function percentile(values, percentileRank) {
  const sorted = [...values].sort((a, b) => a - b);
  if (!sorted.length) return NaN;
  if (sorted.length === 1) return sorted[0];
  const rank = Math.min(Math.max(percentileRank, 0), 100) / 100 * (sorted.length - 1);
  const lower = Math.floor(rank);
  const upper = Math.ceil(rank);
  if (lower === upper) return sorted[lower];
  const weight = rank - lower;
  return sorted[lower] * (1 - weight) + sorted[upper] * weight;
}

function summarizeValues(values) {
  if (!values.length) return null;
  const sum = values.reduce((acc, value) => acc + value, 0);
  return {
    count: values.length,
    avg: sum / values.length,
    max: Math.max(...values),
    p95: percentile(values, 95),
  };
}

function renderMetricGrid(container, metrics, emptyText = "No samples yet.") {
  if (!container) return;
  container.innerHTML = "";
  const visibleMetrics = (metrics || []).filter(Boolean);
  if (!visibleMetrics.length) {
    renderEmptyState(container, emptyText);
    return;
  }
  for (const metric of visibleMetrics) {
    const card = document.createElement("div");
    card.className = "metric-card";
    card.innerHTML = `
      <span>${metric.label}</span>
      <strong>${metric.value}</strong>
      ${metric.sub ? `<small>${metric.sub}</small>` : ""}
    `;
    container.append(card);
  }
}


function formatPercent(value, digits = 1) {
  if (!Number.isFinite(value)) return "-";
  return `${value.toFixed(digits)}%`;
}

function countArray(value) {
  return Array.isArray(value) ? value.length : 0;
}

function countPaths(paths) {
  return (paths || []).reduce((sum, path) => sum + (Array.isArray(path) ? path.length : 0), 0);
}

function renderDiagnosticGrid(container, metrics, emptyText = "No diagnostics yet.") {
  renderMetricGrid(container, metrics, emptyText);
}

function renderDiagnosticTable(container, rows, emptyText = "No diagnostics yet.") {
  if (!container) return;
  container.innerHTML = "";
  const visibleRows = (rows || []).filter(Boolean);
  if (!visibleRows.length) {
    renderEmptyState(container, emptyText);
    return;
  }
  for (const row of visibleRows) {
    const item = document.createElement("div");
    item.className = "diagnostic-row";
    item.innerHTML = `
      <span>${row.label}</span>
      <strong>${row.value}</strong>
      ${row.sub ? `<small>${row.sub}</small>` : ""}
    `;
    container.append(item);
  }
}

function collectFeatureCounts(map = activeMap()) {
  if (!map) return null;
  const roads = [
    ...(map.nationalRoads || []),
    ...(map.ringRoads || []),
    ...(map.externalRoads || []),
    ...(map.expressways || []),
    ...(map.externalExpressways || []),
    ...(map.minorRoads || []),
    ...(map.icAccessRoads || []),
  ];
  const railways = [
    ...(map.railways || []),
    ...(map.branchRailways || []),
    ...(map.ringRailways || []),
    ...(map.externalRailways || []),
  ];
  const rivers = [
    ...(map.mainRivers || []),
    ...(map.tributaryRivers || []),
    ...(map.smallStreams || []),
  ];
  const settlements = [
    ...(map.modernCities || []),
    ...(map.satelliteCities || []),
    ...(map.villages || []),
    ...(map.markets || []),
    ...(map.castles || []),
    ...(map.ports || []),
    ...(map.newTowns || []),
  ];
  const adminBorders = [
    ...(map.adminBorders || []),
    ...(map.prefectureBorder || []),
    ...(map.regionalPrefectureBorders || []),
  ];
  return {
    roads: roads.length,
    roadCells: countPaths(roads),
    railways: railways.length,
    railwayCells: countPaths(railways),
    rivers: rivers.length,
    riverCells: countPaths(rivers),
    settlements: settlements.length,
    stations: countArray(map.stations),
    labels: countArray(state.hoverEntities),
    adminCenters: countArray(map.adminCenters),
    adminBorders: adminBorders.length,
    adminBorderCells: countPaths(adminBorders),
    industrialZones: countArray(map.industrialZones),
    logisticsParks: countArray(map.logisticsParks),
  };
}

function recordDiagnosticLog(level, title, message = "", meta = {}) {
  pushCapped(state.diagnosticLog, {
    id: Date.now() + Math.random(),
    createdAt: new Date(),
    level: level || "info",
    title: title || "Diagnostic",
    message: String(message || ""),
    meta,
  });
  renderAdvancedData();
}

function updateRenderDiagnostics(options = {}, timings = {}) {
  const map = activeMap();
  const canvasRect = canvas?.getBoundingClientRect?.();
  const viewWidth = Math.max(1, state.viewWidth || map?.width || MAP_W);
  const viewHeight = Math.max(1, state.viewHeight || map?.height || MAP_H);
  state.diagnostics.lastViewport = {
    viewWidth,
    viewHeight,
    cells: viewWidth * viewHeight,
    mapWidth: map?.width || viewWidth,
    mapHeight: map?.height || viewHeight,
    cssWidth: canvasRect?.width || 0,
    cssHeight: canvasRect?.height || 0,
    bitmapWidth: canvas?.width || 0,
    bitmapHeight: canvas?.height || 0,
    zoom: state.zoom || 1,
    mode: state.mode,
    fast: !!options.fastTerrain,
    showFeatures: state.showFeatures && !options.fastTerrain,
    showLabels: state.showLabels && !options.fastTerrain,
    showSeamDiagnostics: state.showSeamDiagnostics && !options.fastTerrain,
    viewportMs: timings.viewportMs || 0,
    hoverMs: timings.hoverMs || 0,
    drawMs: timings.drawMs || 0,
    totalRenderMs: timings.totalRenderMs || 0,
    renderBreakdown: timings.renderBreakdown || null,
  };
  state.diagnostics.lastFeatureCounts = collectFeatureCounts(map);
}

function selectionWriteDiagnostics() {
  const rect = state.selectionRect;
  const validation = validatePatchRect(rect, state.world);
  const currentSelection = validation.rect || rect;
  const rects = validation.ok ? buildPatchRects(validation.rect, state.world, { patchMode: patchModeInput?.value || "auto" }) : null;
  const selectedArea = currentSelection?.areaCells || rectAreaCells(currentSelection);
  const writeArea = rects?.writeRect ? rectAreaCells(rects.writeRect) : 0;
  const last = state.patchRuns[0];
  const lastRatio = last?.areaCells ? (last.writeAreaCells || 0) / Math.max(1, last.areaCells) * 100 : NaN;
  return [
    { label: "Current selection", value: selectedArea ? formatAreaCells(selectedArea) : "none", sub: validation.ok ? "valid" : (rect ? validation.reason : "no active selection") },
    { label: "Resolved patch mode", value: rects?.patchMode || "-", sub: rects ? `${rects.patchModeAutoDetected ? "auto" : "explicit"} · ${formatPercent((rects.coverageStats?.ungeneratedRatio || 0) * 100)} ungenerated` : "requires valid selection" },
    { label: "Current write area", value: writeArea ? formatAreaCells(writeArea) : "-", sub: selectedArea ? `${formatPercent(writeArea / Math.max(1, selectedArea) * 100)} of selection` : "requires valid selection" },
    { label: "Last patch selection", value: last ? formatAreaCells(last.areaCells) : "-", sub: last ? `${last.kind || "Patch"} · ${terrainTypeLabel(last.terrainType)}` : "no patch runs" },
    { label: "Last patch write", value: last?.writeAreaCells ? formatAreaCells(last.writeAreaCells) : "-", sub: Number.isFinite(lastRatio) ? `${formatPercent(lastRatio)} of selection` : "no patch runs" },
    { label: "Last patch variant", value: last ? String(last.variant ?? "-") : "-", sub: last?.label || "no candidate" },
  ];
}

function renderViewportDiagnostics() {
  const viewport = state.diagnostics.lastViewport;
  const renderRows = viewport?.renderBreakdown ? [
    { label: "Draw / base", value: formatMs(viewport.renderBreakdown.baseTerrain || 0), sub: "terrain raster" },
    { label: "Draw / urban", value: formatMs(viewport.renderBreakdown.urbanFill || 0), sub: "land-use overlay" },
    { label: "Draw / coast", value: formatMs(viewport.renderBreakdown.coastline || 0), sub: "coastline vectors" },
    { label: "Draw / rivers", value: formatMs(viewport.renderBreakdown.rivers || 0), sub: "river paths" },
    { label: "Draw / admin", value: formatMs(viewport.renderBreakdown.adminBorders || 0), sub: "fills and borders" },
    { label: "Draw / transport", value: formatMs(viewport.renderBreakdown.transport || 0), sub: "roads and rail" },
    { label: "Draw / labels", value: formatMs((viewport.renderBreakdown.icons || 0) + (viewport.renderBreakdown.labels || 0)), sub: "icons and text" },
  ] : [];
  renderDiagnosticGrid(advancedViewportDiagnosticsEl, viewport ? [
    { label: "Viewport", value: `${viewport.viewWidth}×${viewport.viewHeight}`, sub: `${formatAreaCells(viewport.cells)} drawn` },
    { label: "Canvas CSS", value: `${Math.round(viewport.cssWidth)}×${Math.round(viewport.cssHeight)}`, sub: "display pixels" },
    { label: "Canvas bitmap", value: `${viewport.bitmapWidth}×${viewport.bitmapHeight}`, sub: "render target" },
    { label: "Zoom", value: `${Number(viewport.zoom || 1).toFixed(2)}x`, sub: viewport.fast ? "fast redraw" : "full redraw" },
    { label: "Viewport build", value: formatMs(viewport.viewportMs), sub: "getViewportMap" },
    { label: "Canvas draw", value: formatMs(viewport.drawMs), sub: "drawMap" },
    { label: "Hover index", value: formatMs(viewport.hoverMs), sub: "labels / hit targets" },
    { label: "Render total", value: formatMs(viewport.totalRenderMs), sub: `${viewport.mode} mode` },
    ...renderRows,
  ] : [], "No viewport render recorded yet.");

  const counts = state.diagnostics.lastFeatureCounts;
  renderDiagnosticTable(advancedFeatureCountsEl, counts ? [
    { label: "Road paths", value: counts.roads.toLocaleString(), sub: `${counts.roadCells.toLocaleString()} path cells` },
    { label: "Rail paths", value: counts.railways.toLocaleString(), sub: `${counts.railwayCells.toLocaleString()} path cells` },
    { label: "River paths", value: counts.rivers.toLocaleString(), sub: `${counts.riverCells.toLocaleString()} path cells` },
    { label: "Settlements", value: counts.settlements.toLocaleString(), sub: "cities, towns, ports, castles" },
    { label: "Stations", value: counts.stations.toLocaleString(), sub: "rail markers" },
    { label: "Hover labels", value: counts.labels.toLocaleString(), sub: "active hit targets" },
    { label: "Admin centers", value: counts.adminCenters.toLocaleString(), sub: "municipality labels" },
    { label: "Admin borders", value: counts.adminBorders.toLocaleString(), sub: `${counts.adminBorderCells.toLocaleString()} path cells` },
    { label: "Industry / logistics", value: (counts.industrialZones + counts.logisticsParks).toLocaleString(), sub: `${counts.industrialZones} industrial, ${counts.logisticsParks} logistics` },
  ] : [], "No feature counts recorded yet.");
}

function renderPatchDiagnostics() {
  renderDiagnosticTable(advancedPatchDiagnosticsEl, selectionWriteDiagnostics(), "No patch diagnostics yet.");
}

function currentSeamDiagnostics() {
  return state.pendingPatch?.result?.seamDiagnostics
    || state.lastPatchResult?.seamDiagnostics
    || displaySourceMap()?.patchSeamDiagnostics
    || null;
}

function seamDiagnosticRows() {
  const d = currentSeamDiagnostics();
  if (!d) return [];
  const roadTotal = Number(d.roadPortalsBefore || 0);
  const railTotal = Number(d.railPortalsBefore || 0);
  const duplicateParts = [
    `${Number(d.duplicateAdminBoundaryPairs || 0)} municipal`,
    `${Number(d.duplicatePrefectureBoundaryPairs || 0)} prefecture`,
    `${Number(d.overlappingAdminPrefecturePairs || 0)} overlap`,
  ].join(" / ");
  const modeSub = "production-sized full pipeline";
  return [
    { label: "Status", value: String(d.status || "-").toUpperCase(), sub: `${Number(d.criticalCount || 0)} critical / ${Number(d.warningCount || 0)} warning signals` },
    { label: "Patch mode", value: d.patchMode || "-", sub: `${d.patchModeAutoDetected ? "auto-detected" : "explicit"} · ${formatPercent(Number(d.ungeneratedSelectionRatio || 0) * 100)} ungenerated · overlap ${Number(d.expansionOverlap || 0)} cells` },
    { label: "World sea level", value: Number(d.worldSeaLevel || 0).toFixed(3), sub: "shared by initial and additional generation" },
    { label: "Candidate mode", value: d.patchGenerationMode || "-", sub: modeSub },
    { label: "Candidate window", value: `${Number(d.candidateWidth || 0)}×${Number(d.candidateHeight || 0)}`, sub: `${formatPercent(Number(d.candidateAreaRatio || 0) * 100)} of full candidate area` },
    ...(d.qualityPolicyVersion ? [
      { label: "Expansion quality gate", value: d.qualityHardPass ? "PASS" : "BEST AVAILABLE", sub: `${d.qualityPolicyVersion} · score ${Number(d.qualityScore || 0).toFixed(3)} · selected variant ${Number(d.qualitySelectedVariant || 0)}` },
      { label: "Candidate land quality", value: formatPercent(Number(d.qualityLandRatio || 0) * 100), sub: `${d.qualityTerrainType || "-"} · ${formatPercent(Number(d.qualityDevelopableRatio || 0) * 100)} developable · ${formatPercent(Number(d.qualityLargestComponentRatio || 0) * 100)} largest component` },
      { label: "Candidate place density", value: Number(d.qualityLabelCount || 0).toLocaleString(), sub: `${Number(d.qualitySettlementCount || 0)} settlements · ${Number(d.qualityLabelDensityPer1000 || 0).toFixed(2)} labels / 1000 land cells` },
      { label: "Merged patch quality", value: d.qualityFinalHardPass ? "PASS" : "WARNING", sub: `${formatPercent(Number(d.qualityFinalOwnedLandRatio || 0) * 100)} land in owned interior · ${Number(d.qualityFinalLabelCount || 0)} labels / ${Number(d.qualityFinalSettlementCount || 0)} settlements` },
    ] : []),
    { label: "Seam band", value: Number(d.seamBandCells || 0).toLocaleString(), sub: "cells inspected" },
    { label: "Coast flips", value: Number(d.seaFlipCells || 0).toLocaleString(), sub: `${Number(d.landToSeaCells || 0)} land→sea / ${Number(d.seaToLandCells || 0)} sea→land` },
    { label: "Transport/coast conflicts", value: Number(d.transportLandToSeaConflicts || 0).toLocaleString(), sub: "existing road or rail cell changed to sea" },
    { label: "Road seam portals", value: `${Number(d.roadPortalsConnected || 0)}/${roadTotal}`, sub: `${Number(d.roadPortalsBroken || 0)} disconnected` },
    { label: "Rail seam portals", value: `${Number(d.railPortalsConnected || 0)}/${railTotal}`, sub: `${Number(d.railPortalsBroken || 0)} disconnected` },
    { label: "New seam boundaries", value: `${Number(d.adminSeamBreakEdges || 0)} / ${Number(d.prefectureSeamBreakEdges || 0)}`, sub: "municipal / prefecture edges created where the old ID was continuous" },
    { label: "Near-duplicate boundaries", value: Number(d.duplicateBoundaryPairs || 0).toLocaleString(), sub: duplicateParts },
    { label: "Established frontier elevation", value: Number(d.maxEstablishedFrontierElevationJump || 0).toFixed(3), sub: `${Number(d.establishedFrontierElevationEdges || 0).toLocaleString()} land edges inspected · hard limit ${Number(d.gateBudgets?.maxEstablishedFrontierElevationJump || 0.075).toFixed(3)}` },
    { label: "Elevation cliffs", value: Number(d.elevationCliffEdges || 0).toLocaleString(), sub: `max ${Number(d.maxElevationJump || 0).toFixed(3)} / mean ${Number(d.meanElevationJump || 0).toFixed(3)}` },
    { label: "Map markers", value: Number(d.markerCount || 0).toLocaleString(), sub: state.showSeamDiagnostics ? "overlay visible" : "overlay hidden" },
  ];
}

function renderSeamDiagnostics() {
  renderDiagnosticTable(advancedSeamDiagnosticsEl, seamDiagnosticRows(), "Generate a patch preview to collect seam diagnostics.");
}

function renderWorkerWorldDiagnostics() {
  const workerAvailable = typeof Worker !== "undefined";
  const workerRows = [
    { label: "Worker API", value: workerAvailable ? "available" : "unavailable", sub: "browser capability" },
    { label: "Full-generation worker", value: generationWorker ? "active" : "not active", sub: state.diagnostics.lastGenerationWorkerUsed == null ? "created on demand" : (state.diagnostics.lastGenerationWorkerUsed ? "last full generation used worker" : "last full generation used main thread") },
    { label: "Generation fallback", value: state.diagnostics.lastGenerationWorkerFallbackReason || "none", sub: "full-map generation" },
    { label: "Patch worker object", value: patchWorker ? "active" : "not active", sub: patchWorker ? "created" : "created on demand" },
    { label: "Last patch worker", value: state.diagnostics.lastWorkerUsed == null ? "-" : (state.diagnostics.lastWorkerUsed ? "used" : "main thread"), sub: state.diagnostics.lastPatchWorkerKind || "no patch run" },
    { label: "Patch fallback", value: state.diagnostics.lastWorkerFallbackReason || "none", sub: "last patch worker fallback" },
  ];
  renderDiagnosticTable(advancedWorkerDiagnosticsEl, workerRows);

  const world = displayWorld();
  const source = displaySourceMap();
  const expansion = state.diagnostics.lastWorldExpansion;
  renderDiagnosticTable(advancedWorldDiagnosticsEl, [
    { label: "World size", value: world ? `${world.width}×${world.height}` : "-", sub: world ? formatAreaCells(world.width * world.height) : "no world" },
    { label: "Source map", value: source ? `${source.width || MAP_W}×${source.height || MAP_H}` : "-", sub: source ? formatAreaCells((source.width || MAP_W) * (source.height || MAP_H)) : "no source" },
    { label: "Camera", value: state.camera ? `${Math.round(state.camera.x || 0)}, ${Math.round(state.camera.y || 0)}` : "-", sub: "world-space origin" },
    { label: "World expansions", value: state.diagnostics.worldExpansionCount.toLocaleString(), sub: expansion ? `last dx ${expansion.dx}, dy ${expansion.dy}` : "none yet" },
    { label: "Pending patch", value: state.pendingPatch ? "yes" : "no", sub: state.pendingPatch ? `${terrainTypeLabel(state.pendingPatch.terrainType)} · variant ${state.pendingPatch.variant}` : "committed world" },
  ]);
}

function renderWarningHistory() {
  if (!advancedWarningHistoryEl) return;
  advancedWarningHistoryEl.innerHTML = "";
  if (!state.diagnosticLog.length) {
    renderEmptyState(advancedWarningHistoryEl, "No warnings or errors recorded yet.");
    return;
  }
  for (const entry of state.diagnosticLog) {
    const row = document.createElement("div");
    row.className = `diagnostic-log-row ${entry.level || "info"}`;
    const time = entry.createdAt instanceof Date ? entry.createdAt.toLocaleTimeString() : "-";
    row.innerHTML = `
      <span>${time}</span>
      <strong>${entry.title}</strong>
      <p>${entry.message || "-"}</p>
    `;
    advancedWarningHistoryEl.append(row);
  }
}

function performanceMetricsForRuns(runs) {
  const totals = summarizeValues(numericValues(runs, (run) => run.totalMs));
  const perArea = summarizeValues(numericValues(runs, (run) => run.secondsPerThousand));
  if (!totals) return [];
  const hasSmallAreaRuns = (runs || []).some((run) => Number(run?.areaCells) > 0 && Number(run.areaCells) < 1000);
  const perAreaSub = hasSmallAreaRuns ? "area-normalized; small runs include fixed overhead" : "seconds / 1k cells";
  return [
    { label: "Samples", value: String(totals.count), sub: "last 10" },
    { label: "Avg total", value: formatMs(totals.avg), sub: "generation time" },
    { label: "Max total", value: formatMs(totals.max), sub: "slowest run" },
    { label: "P95 total", value: formatMs(totals.p95), sub: "tail latency" },
    perArea ? { label: "Avg / 1k", value: formatSeconds(perArea.avg), sub: perAreaSub } : null,
    perArea ? { label: "P95 / 1k", value: formatSeconds(perArea.p95), sub: hasSmallAreaRuns ? "fixed overhead dominated below 1k cells" : "area-normalized" } : null,
  ];
}

function recordGenerationRun(map, terrainType) {
  if (!map) return;
  const area = mapAreaCells(map);
  const totalMs = Number.isFinite(map.generationTotalMs)
    ? map.generationTotalMs
    : (map.generationTimings || []).reduce((sum, row) => sum + (Number(row?.ms) || 0), 0);
  const featureTimings = (map.transportDebug?.featureTimings || []).map((row) => ({
    label: `Settlements / ${row.key || "substage"}`,
    ms: Number(row.ms) || 0,
  }));
  pushCapped(state.generationRuns, {
    id: Date.now(),
    createdAt: new Date(),
    terrainType: terrainType || "auto",
    areaCells: area,
    totalMs,
    secondsPerThousand: secondsPerThousandCells(totalMs, area),
    timings: (map.generationTimings || []).map((row) => ({
      label: row.label || row.key || "Stage",
      ms: Number(row.ms) || 0,
    })).concat(featureTimings),
  });
  renderAdvancedData();
}

function recordPatchRun(result, terrainType, selectionRect, variant, meta = {}) {
  if (!result) return;
  const timings = (result.patchTimings || []).map((row) => ({
    label: row.label || row.key || "Stage",
    ms: Number(row.ms) || 0,
  }));
  const totalMs = Number.isFinite(meta.wallMs)
    ? meta.wallMs
    : timings.reduce((sum, row) => sum + (Number(row.ms) || 0), 0);
  const selectionArea = result.selectionShape?.areaCells || selectionRect?.areaCells || rectAreaCells(selectionRect);
  const writeArea = rectAreaCells(result.writeRect || result.rects?.writeRect || selectionRect);
  const area = Math.max(1, Math.round(selectionArea || writeArea || 1));
  const writeRatio = writeArea / Math.max(1, area);
  const usedWorker = meta.worker === true;
  pushCapped(state.patchRuns, {
    id: Date.now(),
    createdAt: new Date(),
    kind: meta.kind || "Patch preview",
    terrainType: terrainType || result.terrainType || "auto",
    variant: Number.isFinite(variant) ? variant : result.variant,
    worker: usedWorker,
    label: result.label || "candidate",
    patchGenerationMode: result.patchGenerationMode || "-",
    patchMode: result.patchMode || "regeneration",
    patchModeAutoDetected: !!result.patchModeAutoDetected,
    ungeneratedSelectionRatio: result.coverageStats?.ungeneratedRatio || 0,
    seamStatus: result.seamDiagnostics?.status || "-",
    areaCells: area,
    writeAreaCells: writeArea,
    writeRatio,
    totalMs,
    secondsPerThousand: secondsPerThousandCells(totalMs, area),
    timings,
  });
  state.diagnostics.lastWorkerUsed = usedWorker;
  state.diagnostics.lastPatchWorkerKind = meta.kind || "Patch preview";
  if (usedWorker) state.diagnostics.lastWorkerFallbackReason = null;
  renderAdvancedData();
}

function interactionAction(kind = "") {
  const label = String(kind).toLowerCase();
  if (label.includes("pan")) return "pan";
  if (label.includes("zoom")) return "zoom";
  return label || "other";
}

function interactionPhase(run) {
  return run.fast ? "fast" : "full";
}

function interactionGroupLabel(action, phase) {
  const actionLabel = action === "pan" ? "Pan" : action === "zoom" ? "Zoom" : action;
  return `${actionLabel} / ${phase === "fast" ? "fast redraw" : "full redraw"}`;
}

function recordInteractionLatency(kind, startedAt, meta = {}) {
  if (!Number.isFinite(startedAt)) return;
  const ms = performance.now() - startedAt;
  if (!Number.isFinite(ms) || ms < 0) return;
  const item = {
    id: Date.now(),
    createdAt: new Date(),
    kind,
    ms,
    zoom: Number.isFinite(meta.zoom) ? meta.zoom : state.zoom,
    fast: meta.fast === true,
  };
  item.action = interactionAction(kind);
  item.phase = interactionPhase(item);
  pushCapped(state.interactionRuns, item);
  renderAdvancedData();
}

function renderEmptyState(container, text) {
  if (!container) return;
  container.innerHTML = "";
  const empty = document.createElement("div");
  empty.className = "perf-empty";
  empty.textContent = text;
  container.append(empty);
}

function appendRunHistory(container, runs, options = {}) {
  if (!container) return;
  container.innerHTML = "";
  if (!runs.length) {
    renderEmptyState(container, options.emptyText || "No runs recorded yet.");
    return;
  }
  runs.forEach((run, index) => {
    const item = document.createElement("details");
    item.className = "perf-run";
    if (index === 0) item.open = true;

    const summary = document.createElement("summary");
    summary.className = options.patch ? "perf-summary patch" : "perf-summary";
    const name = options.patch
      ? `${run.kind || "Patch"} · ${terrainTypeLabel(run.terrainType)}`
      : terrainTypeLabel(run.terrainType);
    summary.innerHTML = `
      <span class="perf-rank">#${index + 1}</span>
      <span>${name}</span>
      <strong>${formatMs(run.totalMs)}</strong>
      <span>${formatAreaCells(run.areaCells)}${options.patch && run.writeAreaCells ? ` / write ${formatAreaCells(run.writeAreaCells)}` : ""}</span>
      <span>${formatSeconds(run.secondsPerThousand)} / 1k cells${run.areaCells && run.areaCells < 1000 ? " (fixed overhead)" : ""}</span>
    `;

    const body = document.createElement("div");
    body.className = "timing-grid";
    if (options.patch) {
      const meta = document.createElement("div");
      meta.className = "timing-pill meta";
      meta.innerHTML = `<span>Variant</span><strong>${run.variant ?? "-"}</strong>`;
      const worker = document.createElement("div");
      worker.className = "timing-pill meta";
      worker.innerHTML = `<span>Worker</span><strong>${run.worker ? "yes" : "no"}</strong>`;
      const ratio = document.createElement("div");
      ratio.className = "timing-pill meta";
      ratio.innerHTML = `<span>Write / selection</span><strong>${formatPercent((run.writeRatio || 0) * 100)}</strong>`;
      const candidateMode = document.createElement("div");
      candidateMode.className = "timing-pill meta";
      candidateMode.innerHTML = `<span>Candidate</span><strong>${run.patchGenerationMode || "-"}</strong>`;
      const seam = document.createElement("div");
      seam.className = "timing-pill meta";
      seam.innerHTML = `<span>Seam</span><strong>${String(run.seamStatus || "-").toUpperCase()}</strong>`;
      body.append(meta, worker, ratio, candidateMode, seam);
    }
    for (const row of run.timings) {
      const timing = document.createElement("div");
      timing.className = "timing-pill";
      timing.innerHTML = `<span>${row.label}</span><strong>${formatMs(row.ms)}</strong>`;
      body.append(timing);
    }
    if (!run.timings.length) {
      const empty = document.createElement("div");
      empty.className = "perf-empty inline";
      empty.textContent = "No stage breakdown available.";
      body.append(empty);
    }

    item.append(summary, body);
    container.append(item);
  });
}

function renderGenerationHistory() {
  renderMetricGrid(advancedGenerationStatsEl, performanceMetricsForRuns(state.generationRuns), "No generation runs recorded yet.");
  appendRunHistory(advancedGenerationHistoryEl, state.generationRuns, {
    emptyText: "No generation runs recorded yet.",
  });
}

function renderPatchHistory() {
  renderMetricGrid(advancedPatchStatsEl, performanceMetricsForRuns(state.patchRuns), "No patch generation runs recorded yet.");
  appendRunHistory(advancedPatchHistoryEl, state.patchRuns, {
    patch: true,
    emptyText: "No patch generation runs recorded yet.",
  });
}

function renderInteractionSummary() {
  if (!advancedInteractionStatsEl) return;
  advancedInteractionStatsEl.innerHTML = "";
  if (!state.interactionRuns.length) {
    renderEmptyState(advancedInteractionStatsEl, "No pan or zoom operations recorded yet.");
    return;
  }
  const groups = new Map();
  for (const run of state.interactionRuns) {
    const action = run.action || interactionAction(run.kind);
    const phase = run.phase || interactionPhase(run);
    const key = `${action}:${phase}`;
    if (!groups.has(key)) groups.set(key, { action, phase, values: [] });
    groups.get(key).values.push(run.ms);
  }
  const table = document.createElement("div");
  table.className = "aggregate-table";
  for (const group of groups.values()) {
    const stats = summarizeValues(group.values);
    const row = document.createElement("div");
    row.className = "aggregate-row";
    row.innerHTML = `
      <span>${interactionGroupLabel(group.action, group.phase)}</span>
      <small>n=${stats.count}</small>
      <strong>${formatMs(stats.avg)}</strong>
      <strong>${formatMs(stats.max)}</strong>
      <strong>${formatMs(stats.p95)}</strong>
    `;
    table.append(row);
  }
  advancedInteractionStatsEl.append(table);
}

function renderInteractionHistory() {
  if (!advancedInteractionHistoryEl) return;
  advancedInteractionHistoryEl.innerHTML = "";
  if (!state.interactionRuns.length) {
    renderEmptyState(advancedInteractionHistoryEl, "No pan or zoom operations recorded yet.");
    return;
  }
  const table = document.createElement("div");
  table.className = "interaction-table";
  for (const run of state.interactionRuns) {
    const row = document.createElement("div");
    row.className = "interaction-row";
    row.innerHTML = `
      <span>${run.kind}</span>
      <strong>${formatMs(run.ms)}</strong>
      <span>${Number(run.zoom || 1).toFixed(2)}x</span>
      <span>${run.fast ? "fast" : "full"}</span>
    `;
    table.append(row);
  }
  advancedInteractionHistoryEl.append(table);
}

function renderAdvancedData() {
  renderGenerationHistory();
  renderPatchHistory();
  renderInteractionSummary();
  renderInteractionHistory();
  renderViewportDiagnostics();
  renderPatchDiagnostics();
  renderSeamDiagnostics();
  renderWorkerWorldDiagnostics();
  renderWarningHistory();
}

function reportValue(value) {
  return value == null || value === "" ? "-" : String(value);
}

function reportRows(title, rows = []) {
  const lines = [`[${title}]`];
  const visibleRows = (rows || []).filter(Boolean);
  if (!visibleRows.length) {
    lines.push("- none");
    return lines;
  }
  for (const row of visibleRows) {
    const sub = row.sub ? ` (${row.sub})` : "";
    lines.push(`- ${row.label}: ${reportValue(row.value)}${sub}`);
  }
  return lines;
}

function reportMetrics(title, runs = []) {
  const lines = reportRows(title, performanceMetricsForRuns(runs));
  if (!runs.length) return lines;
  lines.push("Runs:");
  runs.forEach((run, index) => {
    const prefix = run.kind ? `${run.kind} · ` : "";
    const variant = run.kind ? `, variant=${run.variant ?? "-"}, worker=${run.worker ? "yes" : "no"}` : "";
    const write = run.writeAreaCells ? `, write=${formatAreaCells(run.writeAreaCells)}, write/selection=${formatPercent((run.writeRatio || 0) * 100)}` : "";
    lines.push(`  ${index + 1}. ${prefix}${terrainTypeLabel(run.terrainType)}: total=${formatMs(run.totalMs)}, area=${formatAreaCells(run.areaCells)}, sec/1000 cells=${formatSeconds(run.secondsPerThousand)}${variant}${write}`);
    if (run.timings?.length) {
      lines.push(`     breakdown: ${run.timings.map((row) => `${row.label}=${formatMs(row.ms)}`).join(", ")}`);
    }
  });
  return lines;
}

function interactionGroupsForReport() {
  const groups = new Map();
  for (const run of state.interactionRuns) {
    const action = run.action || interactionAction(run.kind);
    const phase = run.phase || interactionPhase(run);
    const key = `${action}:${phase}`;
    if (!groups.has(key)) groups.set(key, { action, phase, values: [] });
    groups.get(key).values.push(run.ms);
  }
  return Array.from(groups.values()).map((group) => {
    const stats = summarizeValues(group.values);
    return {
      label: interactionGroupLabel(group.action, group.phase),
      value: `n=${stats.count}, avg=${formatMs(stats.avg)}, max=${formatMs(stats.max)}, p95=${formatMs(stats.p95)}`,
    };
  });
}

function reportInteractions() {
  const lines = reportRows("Viewport Interaction Latency", interactionGroupsForReport());
  if (!state.interactionRuns.length) return lines;
  lines.push("Recent operations:");
  state.interactionRuns.forEach((run, index) => {
    lines.push(`  ${index + 1}. ${run.kind}: ${formatMs(run.ms)}, zoom=${Number(run.zoom || 1).toFixed(2)}x, phase=${run.fast ? "fast" : "full"}`);
  });
  return lines;
}

function viewportDiagnosticRowsForReport() {
  const viewport = state.diagnostics.lastViewport;
  return viewport ? [
    { label: "Viewport", value: `${viewport.viewWidth}×${viewport.viewHeight}`, sub: `${formatAreaCells(viewport.cells)} drawn` },
    { label: "Canvas CSS", value: `${Math.round(viewport.cssWidth)}×${Math.round(viewport.cssHeight)}`, sub: "display pixels" },
    { label: "Canvas bitmap", value: `${viewport.bitmapWidth}×${viewport.bitmapHeight}`, sub: "render target" },
    { label: "Zoom", value: `${Number(viewport.zoom || 1).toFixed(2)}x`, sub: viewport.fast ? "fast redraw" : "full redraw" },
    { label: "Viewport build", value: formatMs(viewport.viewportMs), sub: "getViewportMap" },
    { label: "Canvas draw", value: formatMs(viewport.drawMs), sub: "drawMap" },
    { label: "Hover index", value: formatMs(viewport.hoverMs), sub: "labels / hit targets" },
    { label: "Render total", value: formatMs(viewport.totalRenderMs), sub: `${viewport.mode} mode` },
  ] : [];
}

function featureCountRowsForReport() {
  const counts = state.diagnostics.lastFeatureCounts;
  return counts ? [
    { label: "Road paths", value: counts.roads.toLocaleString(), sub: `${counts.roadCells.toLocaleString()} path cells` },
    { label: "Rail paths", value: counts.railways.toLocaleString(), sub: `${counts.railwayCells.toLocaleString()} path cells` },
    { label: "River paths", value: counts.rivers.toLocaleString(), sub: `${counts.riverCells.toLocaleString()} path cells` },
    { label: "Settlements", value: counts.settlements.toLocaleString(), sub: "cities, towns, ports, castles" },
    { label: "Stations", value: counts.stations.toLocaleString(), sub: "rail markers" },
    { label: "Hover labels", value: counts.labels.toLocaleString(), sub: "active hit targets" },
    { label: "Admin centers", value: counts.adminCenters.toLocaleString(), sub: "municipality labels" },
    { label: "Admin borders", value: counts.adminBorders.toLocaleString(), sub: `${counts.adminBorderCells.toLocaleString()} path cells` },
    { label: "Industry / logistics", value: (counts.industrialZones + counts.logisticsParks).toLocaleString(), sub: `${counts.industrialZones} industrial, ${counts.logisticsParks} logistics` },
  ] : [];
}

function workerDiagnosticRowsForReport() {
  const workerAvailable = typeof Worker !== "undefined";
  return [
    { label: "Worker API", value: workerAvailable ? "available" : "unavailable", sub: "browser capability" },
    { label: "Full-generation worker", value: generationWorker ? "active" : "not active", sub: state.diagnostics.lastGenerationWorkerUsed == null ? "created on demand" : (state.diagnostics.lastGenerationWorkerUsed ? "last full generation used worker" : "last full generation used main thread") },
    { label: "Generation fallback", value: state.diagnostics.lastGenerationWorkerFallbackReason || "none", sub: "full-map generation" },
    { label: "Patch worker object", value: patchWorker ? "active" : "not active", sub: patchWorker ? "created" : "created on demand" },
    { label: "Last patch worker", value: state.diagnostics.lastWorkerUsed == null ? "-" : (state.diagnostics.lastWorkerUsed ? "used" : "main thread"), sub: state.diagnostics.lastPatchWorkerKind || "no patch run" },
    { label: "Patch fallback", value: state.diagnostics.lastWorkerFallbackReason || "none", sub: "last patch worker fallback" },
  ];
}

function worldDiagnosticRowsForReport() {
  const world = displayWorld();
  const source = displaySourceMap();
  const expansion = state.diagnostics.lastWorldExpansion;
  return [
    { label: "World size", value: world ? `${world.width}×${world.height}` : "-", sub: world ? formatAreaCells(world.width * world.height) : "no world" },
    { label: "Source map", value: source ? `${source.width || MAP_W}×${source.height || MAP_H}` : "-", sub: source ? formatAreaCells((source.width || MAP_W) * (source.height || MAP_H)) : "no source" },
    { label: "Camera", value: state.camera ? `${Math.round(state.camera.x || 0)}, ${Math.round(state.camera.y || 0)}` : "-", sub: "world-space origin" },
    { label: "World expansions", value: state.diagnostics.worldExpansionCount.toLocaleString(), sub: expansion ? `last dx ${expansion.dx}, dy ${expansion.dy}` : "none yet" },
    { label: "Pending patch", value: state.pendingPatch ? "yes" : "no", sub: state.pendingPatch ? `${terrainTypeLabel(state.pendingPatch.terrainType)} · variant ${state.pendingPatch.variant}` : "committed world" },
  ];
}

function reportWarnings() {
  const lines = ["[Warnings / Errors]"];
  if (!state.diagnosticLog.length) {
    lines.push("- none");
    return lines;
  }
  state.diagnosticLog.forEach((entry, index) => {
    const time = entry.createdAt instanceof Date ? entry.createdAt.toISOString() : "-";
    lines.push(`- ${index + 1}. ${time} ${String(entry.level || "info").toUpperCase()} ${entry.title}: ${entry.message || "-"}`);
  });
  return lines;
}

function buildImportantDebugReport() {
  const source = displaySourceMap();
  const summaryRows = getStats(source).map(([label, value]) => ({ label, value }));
  const contextRows = [
    { label: "Generated at", value: new Date().toISOString() },
    { label: "Seed", value: seedInput?.value || state.seedText || "-" },
    { label: "Generation type", value: terrainTypeLabel(generationTypeInput?.value || state.generationType), sub: generationTypeInput?.value || state.generationType },
    { label: "Patch terrain", value: terrainTypeLabel(patchTerrainTypeInput?.value || "auto"), sub: patchTerrainTypeInput?.value || "auto" },
    { label: "Patch mode", value: patchModeInput?.value || "auto", sub: "auto separates expansion from regeneration" },
    { label: "Tool mode", value: state.toolMode || "-" },
    { label: "Display mode", value: state.mode || "-" },
    { label: "Features", value: state.showFeatures ? "on" : "off" },
    { label: "Labels", value: state.showLabels ? "on" : "off" },
  ];
  return [
    "Prefecture Map Generator — Important Debug Data",
    "===============================================",
    ...reportRows("Context", contextRows),
    "",
    ...reportRows("Current Map Summary", summaryRows),
    "",
    ...reportMetrics("Full Generation Performance", state.generationRuns),
    "",
    ...reportMetrics("Patch / Additional Generation Performance", state.patchRuns),
    "",
    ...reportInteractions(),
    "",
    ...reportRows("Viewport Diagnostics", viewportDiagnosticRowsForReport()),
    "",
    ...reportRows("Feature Counts", featureCountRowsForReport()),
    "",
    ...reportRows("Selection / Write Ratio", selectionWriteDiagnostics()),
    "",
    ...reportRows("Seam Diagnostics", seamDiagnosticRows()),
    "",
    ...reportRows("Worker Diagnostics", workerDiagnosticRowsForReport()),
    "",
    ...reportRows("World Diagnostics", worldDiagnosticRowsForReport()),
    "",
    ...reportWarnings(),
  ].join("\n");
}

function setCopyDebugStatus(text, isError = false) {
  if (!copyDebugStatusEl) return;
  copyDebugStatusEl.textContent = text;
  copyDebugStatusEl.classList.toggle("error", !!isError);
  window.clearTimeout(setCopyDebugStatus.timer);
  setCopyDebugStatus.timer = window.setTimeout(() => {
    if (copyDebugStatusEl.textContent === text) copyDebugStatusEl.textContent = "";
    copyDebugStatusEl.classList.remove("error");
  }, 1800);
}

function copyTextFallback(text) {
  const textarea = document.createElement("textarea");
  textarea.value = text;
  textarea.setAttribute("readonly", "");
  textarea.style.position = "fixed";
  textarea.style.left = "-9999px";
  textarea.style.top = "0";
  document.body.append(textarea);
  textarea.select();
  const ok = document.execCommand("copy");
  textarea.remove();
  if (!ok) throw new Error("Copy command failed");
}

async function copyImportantDebugData(event) {
  event?.preventDefault?.();
  event?.stopPropagation?.();
  const text = buildImportantDebugReport();
  try {
    if (navigator.clipboard?.writeText) await navigator.clipboard.writeText(text);
    else copyTextFallback(text);
    setCopyDebugStatus("Copied");
  } catch (error) {
    console.warn("Failed to copy debug data", error);
    try {
      copyTextFallback(text);
      setCopyDebugStatus("Copied");
    } catch (fallbackError) {
      console.warn("Fallback copy failed", fallbackError);
      setCopyDebugStatus("Copy failed", true);
    }
  }
}

function renderTimingRows(timings = []) {
  if (!progressTimingsEl) return;
  progressTimingsEl.innerHTML = "";
  for (const row of timings) {
    const item = document.createElement("div");
    item.className = "progress-timing-row";
    const label = document.createElement("span");
    label.textContent = row.label;
    const value = document.createElement("strong");
    value.textContent = formatMs(row.ms);
    item.append(label, value);
    progressTimingsEl.append(item);
  }
}

function updateGenerationProgress(event) {
  if (!progressEl) return;
  progressEl.classList.remove("hidden");
  if (event?.status === "start") generationCurrentStage = event.label || "Preparing";
  if (progressStageEl) {
    const elapsed = generationStartedAt ? ` / elapsed ${formatMs(performance.now() - generationStartedAt)}` : "";
    progressStageEl.textContent = event?.status === "done"
      ? `Completed: ${event.label} / ${formatMs(event.ms)}${elapsed}`
      : `Running: ${event?.label || generationCurrentStage || "Preparing"}${elapsed}`;
  }
  renderTimingRows(event?.timings || []);
}

function setProgressVisible(visible, message = "Preparing") {
  if (!progressEl) return;
  progressEl.classList.toggle("hidden", !visible);
  if (visible) {
    generationStartedAt = performance.now();
    generationCurrentStage = message;
    if (generationTimer) window.clearInterval(generationTimer);
    generationTimer = window.setInterval(() => {
      if (progressStageEl && !progressEl.classList.contains("hidden")) {
        progressStageEl.textContent = `Running: ${generationCurrentStage || "Preparing"} / elapsed ${formatMs(performance.now() - generationStartedAt)}`;
      }
    }, 100);
  } else if (generationTimer) {
    window.clearInterval(generationTimer);
    generationTimer = null;
  }
  if (progressStageEl) progressStageEl.textContent = message;
  if (visible) renderTimingRows([]);
}

function nextFrame() {
  return new Promise((resolve) => requestAnimationFrame(() => resolve()));
}

function countInside(items) {
  return (items || []).filter((item) => item?.insidePrefecture !== false).length;
}

function totalRailLineCount(map) {
  return (map.railways || []).length + (map.branchRailways || []).length + (map.ringRailways || []).length + (map.externalRailways || []).length;
}

function getStats(map) {
  if (!map) return [];
  return [
    ["Population", (map.totalPopulation || 0).toLocaleString()],
    ["Municipalities", (map.adminCenters || []).length.toLocaleString()],
    ["Major cities", countInside(map.modernCities).toLocaleString()],
    ["Ports", countInside(map.ports).toLocaleString()],
    ["Rail lines", totalRailLineCount(map).toLocaleString()],
    ["Generation", map.generationTotalMs ? formatMs(map.generationTotalMs) : "-"],
  ];
}

function renderStats(map) {
  if (!statsEl) return;
  statsEl.innerHTML = "";
  for (const [labelText, valueText] of getStats(map)) {
    const row = document.createElement("div");
    row.className = "stat-row";

    const label = document.createElement("span");
    label.textContent = labelText;

    const value = document.createElement("strong");
    value.textContent = String(valueText);

    row.append(label, value);
    statsEl.append(row);
  }
}

const legendItems = {
  base: [
    ["terrain-swatch", "Terrain shading"],
    ["river-major", "Rivers and lakes", "line"],
    ["border-swatch", "Prefecture border"],
  ],
  all: [
    ["city-icon", "City / major town", "icon"],
    ["rail-line", "Railway", "line"],
    ["road-line", "Major road", "line"],
    ["river-major", "River", "line"],
    ["border-swatch", "Prefecture border"],
  ],
  terrain: [
    ["terrain-swatch", "Elevation and relief"],
    ["sea-swatch", "Sea / lake"],
    ["river-major", "River system", "line"],
    ["border-swatch", "Prefecture border"],
  ],
  modern: [
    ["city-icon", "Modern city", "icon"],
    ["station-icon", "Station", "icon"],
    ["rail-line", "Railway", "line"],
    ["minor-road-line", "Local road", "line"],
  ],
  history: [
    ["town-icon", "Market / village", "icon"],
    ["castle-icon", "Castle / ruins", "icon"],
    ["port-icon", "Historical port", "icon"],
    ["old-road-line", "Premodern road", "line"],
  ],
  landuse: [
    ["urban-swatch", "Urban land use"],
    ["industry-icon", "Industry / logistics", "icon"],
    ["city-icon", "City core", "icon"],
    ["river-major", "Water body", "line"],
  ],
  admin: [
    ["admin-swatch", "Municipal border"],
    ["border-swatch", "Prefecture border"],
    ["city-icon", "Admin center", "icon"],
  ],
};

function legendRowsForMode(mode) {
  return legendItems[mode] || legendItems.all;
}

function renderLegendGrid(container, rows) {
  if (!container) return;
  container.innerHTML = "";
  for (const [className, text, kind = "swatch"] of rows) {
    const row = document.createElement("div");
    row.className = "legend-row";
    const mark = document.createElement("span");
    mark.className = kind === "line" ? `legend-line ${className}` : kind === "icon" ? `legend-icon ${className}` : `legend-swatch ${className}`;
    const label = document.createElement("span");
    label.textContent = text;
    row.append(mark, label);
    container.append(row);
  }
}

function renderLegend() {
  const rows = legendRowsForMode(state.mode);
  renderLegendGrid(mainLegendGrid, rows);
  renderLegendGrid(floatingLegendGrid, rows.slice(0, 5));
}

function buildHoverEntities(map) {
  return [
    ...(map.modernCities || []),
    ...(map.ports || []),
    ...(map.stations || []),
    ...(map.interchanges || []),
    ...(map.industrialZones || []),
    ...(map.logisticsParks || []),
    ...(map.newTowns || []),
    ...(map.castles || []),
    ...(map.markets || []),
    ...(map.villages || []),
    ...(map.adminCenters || []),
  ];
}

function nearestEntity(items, x, y, maxDistance = 5) {
  let best = null;
  let bestD = maxDistance;
  for (const item of items || []) {
    if (!item || !Number.isFinite(item.x) || !Number.isFinite(item.y)) continue;
    const d = Math.hypot(item.x - x, item.y - y);
    if (d < bestD) { best = item; bestD = d; }
  }
  return best;
}

function landuseName(value) {
  return landuseLabel(value);
}

const ADMIN_ID_KEYS = ["adminId", "municipalityId", "adminNumericId", "id", "numericId"];
const PREFECTURE_ID_KEYS = ["prefectureRegionId", "prefectureId", "id", "numericId"];
const MUNICIPALITY_NAME_KEYS = ["municipalityName", "name", "canonicalSettlementName", "municipalityRootName", "generatedMunicipalityName", "label"];
const PREFECTURE_NAME_KEYS = ["prefectureName", "prefectureRegionName", "regionName", "name", "label"];
const POPULATION_KEYS = ["municipalityPopulation", "adminPopulation", "population", "estimatedPopulation"];

function numericIdOf(item, keys = ADMIN_ID_KEYS) {
  for (const key of keys) {
    const value = item?.[key];
    if (Number.isFinite(value)) return Math.floor(value);
  }
  return null;
}

function hasNumericId(item, id, keys = ADMIN_ID_KEYS) {
  if (!item || id == null || id < 0) return false;
  return keys.some((key) => Number.isFinite(item?.[key]) && Math.floor(item[key]) === Math.floor(id));
}

function numericPrefectureId(item) {
  const value = numericIdOf(item, PREFECTURE_ID_KEYS);
  return value == null ? -1 : value;
}

function firstUsableText(item, keys) {
  for (const key of keys) {
    const value = item?.[key];
    if (!looksNumericName(value)) return String(value).trim();
  }
  return "";
}

function firstPopulation(item) {
  for (const key of POPULATION_KEYS) {
    const value = item?.[key];
    if (Number.isFinite(value) && value > 0) return Math.round(value);
  }
  return null;
}

function adminCenterForId(map, adminId) {
  if (!map || adminId == null || adminId < 0) return null;
  const centers = (map.adminCenters || []).filter(Boolean);
  const exact = centers.find((center) => hasNumericId(center, adminId));
  if (exact) return exact;
  // Some legacy/admin debug arrays were once addressed by array index.  Keep this
  // only as a guarded fallback so numeric IDs are not mistaken for indexes.
  const direct = map.adminCenters?.[adminId];
  return hasNumericId(direct, adminId) ? direct : null;
}

function looksNumericName(name) {
  if (!name) return true;
  const text = String(name).trim();
  return !text || /^県域\d*$/u.test(text) || /^-?\d+(?:\s*[,，]\s*\d+)*$/u.test(text) || /^(Municipality|Prefecture|Admin|Region)\s*-?\d+/i.test(text);
}

function nearestNamedAdminCenter(map, cellIndex, maxDistance = 36, adminId = null) {
  if (!map || cellIndex < 0) return null;
  const x = cellIndex % map.width;
  const y = Math.floor(cellIndex / map.width);
  let best = null;
  let bestD = maxDistance;
  for (const center of map.adminCenters || []) {
    if (!center || !Number.isFinite(center.x) || !Number.isFinite(center.y)) continue;
    if (adminId != null && adminId >= 0 && !hasNumericId(center, adminId)) continue;
    if (!firstUsableText(center, MUNICIPALITY_NAME_KEYS)) continue;
    const d = Math.hypot(center.x - x, center.y - y);
    if (d < bestD) { best = center; bestD = d; }
  }
  return best;
}

function adminName(map, adminId, cellIndex = -1) {
  const center = adminCenterForId(map, adminId) || nearestNamedAdminCenter(map, cellIndex, 54, adminId);
  const name = firstUsableText(center, MUNICIPALITY_NAME_KEYS);
  if (name) return name;
  return adminId >= 0 ? "Unnamed municipality" : "-";
}

function adminPopulation(map, adminId, cellIndex = -1) {
  const center = adminCenterForId(map, adminId) || nearestNamedAdminCenter(map, cellIndex, 54, adminId);
  const centerPop = firstPopulation(center);
  if (centerPop !== null) return centerPop;
  let sum = 0;
  let found = false;
  for (const key of ["modernCities", "satelliteCities", "ports", "markets", "villages"]) {
    for (const p of map?.[key] || []) {
      if (!hasNumericId(p, adminId)) continue;
      const pop = firstPopulation(p);
      if (pop !== null) { sum += pop; found = true; }
    }
  }
  return found ? sum : null;
}

function worldSourceMap() {
  return displayWorld()?.sourceMap || null;
}

function prefectureRegionById(id, maps = []) {
  if (!Number.isFinite(id) || id < 0) return null;
  for (const source of maps) {
    const region = (source?.prefectureRegions || []).find((p) => hasNumericId(p, id, PREFECTURE_ID_KEYS));
    if (region) return region;
  }
  return null;
}

function prefectureNameForId(id, adminId = -1) {
  if (!Number.isFinite(id) || id < 0) return "";
  const sources = [activeMap(), worldSourceMap()].filter(Boolean);
  const region = prefectureRegionById(id, sources);
  const regionName = firstUsableText(region, PREFECTURE_NAME_KEYS);
  if (regionName) return regionName;

  for (const source of sources) {
    for (const center of source?.adminCenters || []) {
      if (adminId >= 0 && !hasNumericId(center, adminId)) continue;
      const centerPref = numericPrefectureId(center);
      if (centerPref >= 0 && centerPref !== id) continue;
      const name = firstUsableText(center, ["prefectureName", "prefectureRegionName", "regionName"]);
      if (name) return name;
    }
  }
  return "";
}

function prefectureNameForCell(map, i) {
  const id = map.prefectureRegionId?.[i] ?? -1;
  const direct = prefectureNameForId(id);
  if (direct) return direct;
  const adminId = map.adminId?.[i] ?? -1;
  const mappedPref = adminId >= 0 ? map.municipalityToPrefectureId?.[adminId] ?? state.world?.sourceMap?.municipalityToPrefectureId?.[adminId] ?? -1 : -1;
  const mapped = prefectureNameForId(mappedPref, adminId);
  if (mapped) return mapped;
  const center = mappedPref === id ? nearestNamedAdminCenter(map, i, 90, adminId) : null;
  const fromCenter = firstUsableText(center, ["prefectureName", "prefectureRegionName", "regionName"]);
  return fromCenter || (id >= 0 ? "Unnamed prefecture" : "-");
}

function updateTooltip(event) {
  const map = activeMap();
  if (!map || !tooltipEl || dragState.mode) return;
  const rect = canvas.getBoundingClientRect();
  const cell = mapClientToCell(event);
  if (!cell) return;
  const { x, y } = cell;
  if (x < 0 || y < 0 || x >= map.width || y >= map.height) {
    tooltipEl.classList.remove("visible");
    return;
  }
  const i = y * map.width + x;
  const worldCell = viewportCellToWorldCell({ x, y });
  const entity = nearestEntity(state.hoverEntities, x, y);
  const elevation = map.elevation?.[i] ?? 0;
  const density = map.populationDensity?.[i] ?? map.settlementScore?.[i] ?? 0;
  const hoveredAdminId = map.adminId?.[i] ?? -1;
  const hoveredAdminPopulation = adminPopulation(map, hoveredAdminId, i);
  const coordinateText = worldCell ? `World ${worldCell.x}, ${worldCell.y} / View ${x}, ${y}` : `${x}, ${y}`;
  const entityName = firstUsableText(entity, ["name", "facilityLabel", "municipalityName", "canonicalSettlementName", "kind"]);
  const entityTitle = entity
    ? `${entityName || adminName(map, hoveredAdminId, i) || entity.kind || "Feature"} / ${entity.kind || "Feature"}`
    : coordinateText;
  const lines = [
    `<strong>${entityTitle}</strong>`,
    `Prefecture: ${prefectureNameForCell(map, i)}`,
    `Admin: ${adminName(map, hoveredAdminId, i)}`,
    `Admin Pop: ${hoveredAdminPopulation === null ? "-" : hoveredAdminPopulation.toLocaleString()}`,
    `Land: ${map.sea?.[i] ? "Sea" : landuseName(map.landuse?.[i])}`,
    `Elevation: ${elevation.toFixed(3)} / Slope: ${(map.slope?.[i] ?? 0).toFixed(3)}`,
    `River: ${(map.river?.[i] ?? 0).toFixed(2)} / Density: ${density.toFixed(2)}`,
  ];
  if (entity?.population) lines.splice(1, 0, `Population: ${entity.population.toLocaleString()}`);
  tooltipEl.innerHTML = lines.join("<br>");
  const margin = 8;
  const offset = 14;
  const maxLeft = Math.max(margin, rect.width - tooltipEl.offsetWidth - margin);
  const maxTop = Math.max(margin, rect.height - tooltipEl.offsetHeight - margin);
  const desiredLeft = event.clientX - rect.left + offset;
  const desiredTop = event.clientY - rect.top + offset;
  tooltipEl.style.left = `${Math.min(Math.max(margin, desiredLeft), maxLeft)}px`;
  tooltipEl.style.top = `${Math.min(Math.max(margin, desiredTop), maxTop)}px`;
  tooltipEl.classList.add("visible");
}

function renderModeButtons() {
  if (!modeGrid) return;
  modeGrid.innerHTML = "";
  for (const [key, label] of modes) {
    const button = document.createElement("button");
    button.type = "button";
    button.textContent = label;
    button.className = key === state.mode ? "mode-button active" : "mode-button";
    button.addEventListener("click", () => {
      state.mode = key;
      renderModeButtons();
      renderLegend();
      redraw();
    });
    modeGrid.append(button);
  }
  renderLegend();
}

function rejectGenerationJobs(error) {
  for (const pending of generationPendingJobs.values()) pending.reject(error);
  generationPendingJobs.clear();
}

function resetGenerationWorker(reason = "Generation worker reset", rejectPending = true) {
  const worker = generationWorker;
  generationWorker = null;
  worker?.terminate?.();
  if (rejectPending && generationPendingJobs.size) rejectGenerationJobs(new Error(reason));
}

function createGenerationWorker() {
  if (generationWorker) return generationWorker;
  if (typeof Worker === "undefined") {
    state.diagnostics.lastGenerationWorkerFallbackReason = "Worker API unavailable";
    return null;
  }
  try {
    const worker = new Worker(new URL("./generationWorker.js", import.meta.url), { type: "module" });
    worker.addEventListener("message", (event) => {
      const data = event.data || {};
      const pending = generationPendingJobs.get(data.id);
      if (!pending) return;
      if (data.type === "progress") {
        pending.onProgress?.(data.event || {});
        return;
      }
      if (data.type !== "result") return;
      generationPendingJobs.delete(data.id);
      if (data.ok) pending.resolve({ map: data.map, worker: true });
      else pending.reject(new Error(data.error || "Generation worker failed"));
    });
    worker.addEventListener("error", (event) => {
      if (generationWorker !== worker) return;
      const reason = event?.message || "Generation worker runtime error";
      state.diagnostics.lastGenerationWorkerFallbackReason = reason;
      recordDiagnosticLog("error", "Generation worker reset", reason);
      resetGenerationWorker(reason, true);
    });
    worker.addEventListener("messageerror", () => {
      if (generationWorker !== worker) return;
      const reason = "Generation worker message clone failed";
      state.diagnostics.lastGenerationWorkerFallbackReason = reason;
      recordDiagnosticLog("error", "Generation worker reset", reason);
      resetGenerationWorker(reason, true);
    });
    generationWorker = worker;
    return worker;
  } catch (error) {
    state.diagnostics.lastGenerationWorkerFallbackReason = error?.message || "Generation worker creation failed";
    generationWorker = null;
    return null;
  }
}

function runGenerationInWorker(seed, options = {}, onProgress = null) {
  const worker = createGenerationWorker();
  if (!worker) return null;
  const id = ++generationJobSeq;
  return new Promise((resolve, reject) => {
    generationPendingJobs.set(id, { resolve, reject, onProgress });
    try {
      worker.postMessage({ id, seed, options });
    } catch (error) {
      generationPendingJobs.delete(id);
      reject(error);
    }
  });
}

async function generateFullMap(seed, options = {}) {
  // Full-map generation used to run on the UI thread.  A slow browser could
  // therefore trigger the browser's long-running-script watchdog after tens of
  // seconds even though generation itself was still making progress.  Keep the
  // complete CPU-bound pipeline in a worker; only progress messages and the
  // finished map cross back to the UI thread.
  const workerPromise = runGenerationInWorker(seed, { terrainType: options.terrainType }, options.onProgress);
  if (workerPromise) {
    const job = await workerPromise;
    state.diagnostics.lastGenerationWorkerUsed = true;
    state.diagnostics.lastGenerationWorkerFallbackReason = null;
    return job.map;
  }

  // Do not restart a CPU-heavy full generation on the UI thread. On slower
  // browsers that old compatibility fallback could hit the long-running-script
  // watchdog after tens of seconds. Modern browser execution therefore
  // requires a worker; if workers are blocked, fail immediately with a useful
  // diagnostic instead of appearing to generate and then being interrupted.
  state.diagnostics.lastGenerationWorkerUsed = false;
  const reason = state.diagnostics.lastGenerationWorkerFallbackReason || "Generation worker unavailable";
  throw new Error(`${reason}. Full-map generation requires Web Worker support (serve the app over HTTP/HTTPS if local file workers are blocked).`);
}

async function regenerate() {
  const requestId = ++generationRequestSeq;
  ++patchRequestSeq;
  state.patchBusy = false;
  state.patchBusyVariant = null;
  state.patchStatusMessage = "";
  if (patchWorker) { patchWorker.terminate?.(); patchWorker = null; }
  state.seedText = seedInput.value;
  state.generationType = generationTypeInput?.value || "auto";
  // A deliberate new Generate request supersedes an older one. Do not leave
  // multiple full-map jobs queued behind a busy worker.
  if (generationPendingJobs.size) resetGenerationWorker("Generation superseded by a newer request", true);
  setProgressVisible(true, "Preparing generation...");
  await nextFrame();
  try {
    const map = await generateFullMap(parseSeed(state.seedText), { onProgress: updateGenerationProgress, terrainType: state.generationType });
    if (requestId !== generationRequestSeq) return;
    state.map = map;
    state.world = createWorldMap(state.map);
    state.camera = createInitialCamera(state.world);
    state.lastPatchResult = null;
    state.pendingPatch = null;
    resetPatchVariant({ update: false });
    hideSelectionOverlay({ discardPreview: true });
    recordGenerationRun(state.map, state.generationType);
    renderStats(state.map);
    redraw();
    if (progressStageEl) {
      const workerText = state.diagnostics.lastGenerationWorkerUsed ? " in worker" : "";
      progressStageEl.textContent = `Done${workerText} in ${formatMs(state.map.generationTotalMs || 0)}`;
    }
    renderTimingRows(state.map.generationTimings || []);
    window.setTimeout(() => setProgressVisible(false), 900);
  } catch (error) {
    // Superseding an old request is an expected cancellation, not a generation
    // failure. The newer request owns the progress UI.
    if (requestId !== generationRequestSeq) return;
    const reason = error?.message || String(error || "unknown generation error");
    recordDiagnosticLog("error", "Full generation failed", reason, { terrainType: state.generationType });
    if (progressStageEl) progressStageEl.textContent = `Generation failed: ${reason}`;
    console.error("Full generation failed", error);
  }
}


function derivePatchSeed(rect, terrainType, variant = 0) {
  let h = parseSeed(state.seedText) ^ 0x9e3779b9;
  h = Math.imul(h ^ (rect.x0 | 0), 1664525) >>> 0;
  h = Math.imul(h ^ (rect.y0 | 0), 1013904223) >>> 0;
  h = Math.imul(h ^ (rect.x1 | 0), 2246822519) >>> 0;
  h = Math.imul(h ^ (rect.y1 | 0), 3266489917) >>> 0;
  h = Math.imul(h ^ normalizePatchVariant(variant), 668265263) >>> 0;
  for (const ch of String(terrainType || "auto")) h = Math.imul(h ^ ch.charCodeAt(0), 16777619) >>> 0;
  return h >>> 0;
}



function beginZoomVisual(oldZoom, event) {
  if (zoomVisualState) return;
  const rect = canvas.getBoundingClientRect();
  zoomVisualState = {
    baseRect: rect,
    startZoom: clampZoom(oldZoom || state.zoom || 1),
    originX: Math.min(Math.max(event.clientX - rect.left, 0), rect.width),
    originY: Math.min(Math.max(event.clientY - rect.top, 0), rect.height),
  };
  canvas.style.transformOrigin = `${zoomVisualState.originX}px ${zoomVisualState.originY}px`;
  canvas.style.willChange = "transform";
  canvas.classList.add("is-zooming");
  if (selectionSvgEl) selectionSvgEl.style.visibility = "hidden";
}

function scheduleZoomVisualUpdate() {
  if (!zoomVisualState || zoomRedrawRaf != null) return;
  zoomRedrawRaf = requestAnimationFrame(() => {
    zoomRedrawRaf = null;
    if (!zoomVisualState) return;
    const scale = clampZoom(state.zoom || 1) / Math.max(1e-6, zoomVisualState.startZoom || 1);
    canvas.style.transform = `scale(${scale})`;
  });
}

function finishZoomVisual() {
  if (zoomRedrawRaf != null) {
    cancelAnimationFrame(zoomRedrawRaf);
    zoomRedrawRaf = null;
  }
  if (zoomVisualState) {
    canvas.style.transform = "";
    canvas.style.transformOrigin = "";
    canvas.style.willChange = "";
    canvas.classList.remove("is-zooming");
    if (selectionSvgEl) selectionSvgEl.style.visibility = "";
    zoomVisualState = null;
  }
}

function handleCanvasWheel(event) {
  if (!state.world || !activeMap()) return;
  event.preventDefault();
  if (zoomLatencyStartedAt == null) zoomLatencyStartedAt = performance.now();
  tooltipEl?.classList.remove("visible");
  const beforeSize = viewportSizeForZoom(state.zoom);
  const beforeCell = mapClientToCell(event, beforeSize);
  const beforeWorld = beforeCell ? viewportCellToWorldCell(beforeCell) : null;
  const oldZoom = clampZoom(state.zoom || 1);
  const delta = event.deltaY < 0 ? 1.10 : 1 / 1.10;
  const nextZoom = clampZoom(oldZoom * delta);
  if (Math.abs(nextZoom - oldZoom) < 0.001) return;
  state.zoom = nextZoom;
  const nextSize = syncViewportSize();
  if (beforeWorld) {
    const afterCell = mapClientToCell(event, nextSize);
    if (afterCell) {
      state.camera = clampCameraForView({
        x: beforeWorld.x - afterCell.x,
        y: beforeWorld.y - afterCell.y,
      }, nextSize);
    }
  }

  // Wheel events can fire dozens of times per second.  During the gesture, keep
  // the last rendered bitmap and only transform it on the GPU; rebuild the
  // viewport and labels once the gesture settles.
  beginZoomVisual(oldZoom, event);
  scheduleZoomVisualUpdate();
  if (zoomSettledTimer != null) clearTimeout(zoomSettledTimer);
  zoomSettledTimer = window.setTimeout(() => {
    zoomSettledTimer = null;
    const startedAt = zoomLatencyStartedAt || performance.now();
    zoomLatencyStartedAt = null;
    finishZoomVisual();
    redraw({ fastTerrain: false, allowWorldExpand: false });
    recordInteractionLatency("wheel zoom", startedAt, { zoom: state.zoom });
  }, 170);
}

function cloneForPatchPreview(value, seen = new Map()) {
  if (value == null || typeof value !== "object") return value;
  if (ArrayBuffer.isView(value)) return new value.constructor(value);
  if (value instanceof ArrayBuffer) return value.slice(0);
  if (seen.has(value)) return seen.get(value);
  if (value instanceof Map) {
    const out = new Map();
    seen.set(value, out);
    for (const [k, v] of value.entries()) out.set(cloneForPatchPreview(k, seen), cloneForPatchPreview(v, seen));
    return out;
  }
  if (Array.isArray(value)) {
    const out = [];
    seen.set(value, out);
    for (const item of value) out.push(cloneForPatchPreview(item, seen));
    return out;
  }
  const out = {};
  seen.set(value, out);
  for (const [key, item] of Object.entries(value)) out[key] = cloneForPatchPreview(item, seen);
  return out;
}


function clonePatchPreviewWorld(world) {
  if (typeof structuredClone === "function") {
    try {
      return structuredClone(world);
    } catch (error) {
      recordDiagnosticLog("warning", "Native patch clone fallback", error?.message || String(error));
    }
  }
  return cloneForPatchPreview(world);
}

function previewPatchDelta(baseWorld, previewWorld, rectLike) {
  const rect = rectLike?.writeRect || rectLike || null;
  if (!baseWorld || !previewWorld || !rect) return null;
  const x0 = Math.max(0, Math.floor(rect.x0 || 0));
  const y0 = Math.max(0, Math.floor(rect.y0 || 0));
  const x1 = Math.min(Math.max(baseWorld.width || 0, previewWorld.width || 0), Math.ceil(rect.x1 || 0));
  const y1 = Math.min(Math.max(baseWorld.height || 0, previewWorld.height || 0), Math.ceil(rect.y1 || 0));
  const terrainFields = ["elevation", "sea", "landuse", "populationDensity"];
  const adminFields = ["adminId", "municipalityId", "prefectureRegionId"];
  let changedCells = 0;
  let terrainChangedCells = 0;
  let adminChangedCells = 0;
  for (let y = y0; y < y1; y++) {
    for (let x = x0; x < x1; x++) {
      const bi = worldIndexOf(baseWorld, x, y);
      const pi = worldIndexOf(previewWorld, x, y);
      if (bi < 0 || pi < 0) continue;
      let terrainChanged = false;
      let adminChanged = false;
      for (const name of terrainFields) {
        const a = baseWorld.fields?.[name]?.[bi];
        const b = previewWorld.fields?.[name]?.[pi];
        if (a !== b && !(Number.isNaN(a) && Number.isNaN(b))) { terrainChanged = true; break; }
      }
      for (const name of adminFields) {
        const a = baseWorld.fields?.[name]?.[bi];
        const b = previewWorld.fields?.[name]?.[pi];
        if (a !== b) { adminChanged = true; break; }
      }
      if (terrainChanged || adminChanged) changedCells++;
      if (terrainChanged) terrainChangedCells++;
      if (adminChanged) adminChangedCells++;
    }
  }
  return { changedCells, terrainChangedCells, adminChangedCells };
}

function markPreviewRenderRevision(world, variant) {
  if (!world) return 0;
  const revision = ++state.renderRevision;
  world.renderRevision = revision;
  world.previewVariant = variant;
  return revision;
}

function createPatchWorker() {
  if (patchWorker) return patchWorker;
  if (typeof Worker === "undefined") {
    state.diagnostics.lastWorkerFallbackReason = "Worker API unavailable";
    return null;
  }
  try {
    patchWorker = new Worker(new URL("./mapPatchWorker.js", import.meta.url), { type: "module" });
    const worker = patchWorker;
    worker.addEventListener("error", (event) => {
      if (patchWorker !== worker) return;
      const reason = event?.message || "Patch worker runtime error";
      state.diagnostics.lastWorkerFallbackReason = reason;
      recordDiagnosticLog("warning", "Patch worker reset", reason);
      worker.terminate?.();
      patchWorker = null;
    });
  } catch (error) {
    state.diagnostics.lastWorkerFallbackReason = error?.message || "Patch worker creation failed";
    patchWorker = null;
  }
  return patchWorker;
}

function runPatchInWorker(world, rect, options) {
  const worker = createPatchWorker();
  if (!worker) return null;
  const id = ++patchJobSeq;
  return new Promise((resolve, reject) => {
    let settled = false;
    let watchdogTimer = null;
    const resetWatchdog = () => {
      if (watchdogTimer != null) clearTimeout(watchdogTimer);
      watchdogTimer = window.setTimeout(() => {
        fail(new Error(`Patch worker produced no progress for ${Math.round(PATCH_WORKER_INACTIVITY_WATCHDOG_MS / 1000)} seconds and was stopped.`));
      }, PATCH_WORKER_INACTIVITY_WATCHDOG_MS);
    };
    const cleanup = () => {
      if (watchdogTimer != null) { clearTimeout(watchdogTimer); watchdogTimer = null; }
      worker.removeEventListener("message", onMessage);
      worker.removeEventListener("error", onError);
      worker.removeEventListener("messageerror", onMessageError);
      if (activePatchCancel === cancelJob) activePatchCancel = null;
      if (patchWorker === worker) patchWorker = null;
      worker.terminate?.();
    };
    const succeed = (value) => { if (settled) return; settled = true; cleanup(); resolve(value); };
    const fail = (error) => { if (settled) return; settled = true; cleanup(); reject(error instanceof Error ? error : new Error(String(error || "Patch worker failed"))); };
    const cancelJob = (reason = "Patch generation cancelled by user.") => {
      const error = new Error(reason);
      error.name = "AbortError";
      fail(error);
    };
    const onMessage = (event) => {
      if (event.data?.id !== id) return;
      resetWatchdog();
      if (event.data?.type === "progress") { updateGenerationProgress(event.data.progress || {}); return; }
      if (event.data.ok) succeed({ world: event.data.world, result: event.data.result, worker: true });
      else fail(new Error(event.data.error || "Patch worker failed"));
    };
    const onError = (event) => fail(new Error(event.message || "Patch worker error"));
    const onMessageError = () => fail(new Error("Patch worker message clone failed"));
    worker.addEventListener("message", onMessage);
    worker.addEventListener("error", onError);
    worker.addEventListener("messageerror", onMessageError);
    activePatchCancel = cancelJob;
    resetWatchdog();
    const previewWorld = clonePatchPreviewWorld(world);
    const transfer = Array.from(collectTransferableBuffers(previewWorld));
    try { worker.postMessage({ id, world: previewWorld, rect, options }, transfer); }
    catch (error) { fail(error); }
  });
}

function cancelPatchGeneration({ clearSelection = false } = {}) {
  if (!state.patchBusy) return false;
  patchRequestSeq++;
  const cancel = activePatchCancel;
  activePatchCancel = null;
  cancel?.("Patch generation cancelled by user.");
  patchWorker?.terminate?.();
  patchWorker = null;
  state.patchBusy = false;
  state.patchBusyVariant = null;
  state.patchStatusMessage = "Generation cancelled.";
  setProgressVisible(false);
  if (clearSelection) hideSelectionOverlay({ discardPreview: true });
  else updatePatchControls();
  return true;
}

async function generatePatchPreviewWorld(baseWorld, rect, options) {
  const workerPromise = runPatchInWorker(baseWorld, rect, options);
  if (workerPromise) {
    try {
      return await workerPromise;
    } catch (error) {
      const reason = error?.message || String(error || "unknown worker failure");
      // A worker that dies after a long patch must not silently restart the same
      // CPU-heavy job on the UI thread. That old fallback could turn a worker
      // failure into a second long freeze and trigger the browser watchdog.
      state.diagnostics.lastWorkerFallbackReason = reason;
      recordDiagnosticLog("error", "Patch worker failed", reason);
      patchWorker?.terminate?.();
      patchWorker = null;
      throw error;
    }
  }
  const reason = state.diagnostics.lastWorkerFallbackReason || "Patch worker unavailable";
  throw new Error(`${reason}. Patch generation requires Web Worker support (serve the app over HTTP/HTTPS if local file workers are blocked).`);
}

async function generateSelectedPatch(kind = "Patch preview") {
  if (state.patchBusy) return;
  const validation = validatePatchRect(state.selectionRect, state.world);
  if (!validation.ok) {
    recordDiagnosticLog("warning", "Invalid patch selection", validation.reason || "Selection is not valid.");
    updatePatchControls();
    return;
  }
  const baseWorld = state.world;
  const requestId = ++patchRequestSeq;
  const terrainType = patchTerrainTypeInput?.value || generationTypeInput?.value || "auto";
  const patchMode = patchModeInput?.value || "auto";
  const variant = readPatchVariant();
  const seed = derivePatchSeed(validation.rect, terrainType, variant);
  state.patchBusy = true;
  state.patchBusyVariant = variant;
  state.patchStatusMessage = "";
  updatePatchControls();
  setProgressVisible(true, `Generating preview variant ${variant}...`);
  await nextFrame();
  const patchStartedAt = performance.now();
  try {
    const job = await generatePatchPreviewWorld(baseWorld, validation.rect, {
      terrainType,
      patchMode,
      seed,
      variant,
      // An interactive Alternative click is already the retry mechanism. Do not
      // silently run a second complete patch attempt, which can double wall time
      // and look like a browser-enforced interruption on slower machines.
      maxQualityRetries: 0,
      // Alternative is itself the candidate search UI. Generate exactly the
      // requested variant instead of internally searching variant N/N+1/N+2;
      // overlapping internal searches could select the same candidate on two
      // consecutive Alternative clicks and made the map look unchanged.
      qualityTerrainAttempts: 1,
      // Preview generation may remain visible when the single requested
      // expansion candidate only misses a terrain/human-geography quality floor.
      // Hard seam-continuity failures are never accepted as best-available and
      // are rolled back instead of displaying a visibly broken generation edge.
      acceptBestAvailableQuality: true,
      includeSeamVisualization: state.showSeamDiagnostics,
    });
    if (requestId !== patchRequestSeq || state.world !== baseWorld) return;
    const result = job.result;
    if (!result.ok) {
      const reason = result.reason || result.code || "invalid selection";
      const showing = state.pendingPatch?.variant;
      state.patchStatusMessage = showing == null
        ? `Variant ${variant} was rejected (${reason}); no preview was applied.`
        : `Variant ${variant} was rejected (${reason}); still showing preview variant ${showing}.`;
      recordDiagnosticLog("warning", "Patch failed", reason, { kind, terrainType, variant });
      if (progressStageEl) progressStageEl.textContent = state.patchStatusMessage;
      updatePatchControls();
      return;
    }
    const patchWallMs = performance.now() - patchStartedAt;
    const previewDelta = previewPatchDelta(baseWorld, job.world, result.rects || validation.rect) || { changedCells: 0, terrainChangedCells: 0, adminChangedCells: 0 };
    result.previewDelta = previewDelta;
    markPreviewRenderRevision(job.world, variant);
    state.pendingPatch = { world: job.world, result, rect: validation.rect, terrainType, seed, variant, worker: job.worker, previewDelta };
    recordPatchRun(result, terrainType, validation.rect, variant, { kind, worker: job.worker, wallMs: patchWallMs });
    state.viewportMap = null;
    if (progressStageEl) progressStageEl.textContent = `Rendering preview variant ${variant}...`;
    await nextFrame();
    const renderStartedAt = performance.now();
    // Render the finished candidate in full immediately. A fast redraw followed
    // by a delayed full redraw made completion ambiguous and could preserve a
    // visually stale cached frame long enough to look like the result was lost.
    redraw({ fastTerrain: false, allowWorldExpand: false });
    const renderMs = performance.now() - renderStartedAt;
    renderStats(displaySourceMap());
    state.patchStatusMessage = previewDelta.changedCells > 0
      ? `Variant ${variant} is displayed (render revision ${job.world.renderRevision}); ${previewDelta.changedCells.toLocaleString()} cells differ from the committed map.`
      : `Variant ${variant} completed but is identical to the committed map in the write area.`;
    updatePatchControls();
    if (progressStageEl) {
      const modeText = `${result.patchMode || patchMode} / ${result.patchGenerationMode}`;
      const quality = result.candidateQuality;
      const qualityText = quality
        ? ` / quality ${quality.hardPass ? "PASS" : "best available"} ${Number(quality.score || 0).toFixed(3)} / selected terrain variant ${Number(quality.selectedVariant || 0)}`
        : "";
      progressStageEl.textContent = `Preview variant ${variant} displayed${job.worker ? " from worker" : ""}: ${previewDelta.changedCells.toLocaleString()} changed cells / generation ${formatMs(patchWallMs)} / render ${formatMs(renderMs)}${qualityText} / ${modeText}.`;
    }
    if (result.candidateQuality && !result.candidateQuality.hardPass) {
      recordDiagnosticLog("warning", "Expansion quality floor not fully met", `Selected the best available production candidate (score ${Number(result.candidateQuality.score || 0).toFixed(3)}).`, { terrainType, variant, candidateQuality: result.candidateQuality });
    }
    renderTimingRows(result.patchTimings || []);
    window.setTimeout(() => setProgressVisible(false), 1400);
  } catch (error) {
    if (error?.name === "AbortError") {
      state.patchStatusMessage = "Generation cancelled.";
      updatePatchControls();
      return;
    }
    if (requestId !== patchRequestSeq) return;
    const reason = error?.message || String(error || "unknown patch error");
    const showing = state.pendingPatch?.variant;
    state.patchStatusMessage = showing == null
      ? `Variant ${variant} failed (${reason}); no preview was applied.`
      : `Variant ${variant} failed (${reason}); still showing preview variant ${showing}.`;
    recordDiagnosticLog("error", "Patch exception", reason, { kind, terrainType, variant });
    if (progressStageEl) progressStageEl.textContent = state.patchStatusMessage;
    console.error("Patch generation failed", error);
  } finally {
    if (requestId === patchRequestSeq) {
      state.patchBusy = false;
      state.patchBusyVariant = null;
      updatePatchControls();
      if (!progressEl?.classList.contains("hidden")) window.setTimeout(() => setProgressVisible(false), 1800);
    }
  }
}

async function generateAlternativePatch() {
  if (state.patchBusy) return;
  const validation = validatePatchRect(state.selectionRect, state.world);
  if (!validation.ok) {
    updatePatchControls();
    return;
  }
  setPatchVariant(readPatchVariant() + 1, { update: false });
  await generateSelectedPatch("Patch alternative");
}

function redraw(options = {}) {
  const redrawStartedAt = performance.now();
  const renderWorld = displayWorld();
  if (!renderWorld) return;
  const viewSize = syncViewportSize();
  // Patch workers clone world coordinates at launch. Expanding the committed
  // world while a patch is running shifts origin/fields in-place and makes the
  // returning preview use a stale coordinate frame. Defer automatic expansion
  // until generation has finished.
  const mayExpand = !state.pendingPatch && !state.patchBusy && options.allowWorldExpand !== false;
  const expansion = mayExpand ? ensureWorldPaddingForCamera(state.world, state.camera, viewSize.width, viewSize.height) : null;
  if (expansion?.expanded) {
    const ex = expansion.dx || 0;
    const ey = expansion.dy || 0;
    state.diagnostics.worldExpansionCount += 1;
    state.diagnostics.lastWorldExpansion = {
      at: new Date(),
      dx: ex,
      dy: ey,
      worldWidth: state.world?.width || 0,
      worldHeight: state.world?.height || 0,
      viewWidth: viewSize.width,
      viewHeight: viewSize.height,
    };
    state.camera = { x: (state.camera?.x || 0) + ex, y: (state.camera?.y || 0) + ey };
    if (dragState.mode === "pan") {
      dragState.startCameraX += ex;
      dragState.startCameraY += ey;
      if (dragState.pendingCamera) dragState.pendingCamera = { x: dragState.pendingCamera.x + ex, y: dragState.pendingCamera.y + ey };
    }
    if (state.selectionRect) {
      state.selectionRect = {
        ...state.selectionRect,
        x0: state.selectionRect.x0 + ex,
        y0: state.selectionRect.y0 + ey,
        x1: state.selectionRect.x1 + ex,
        y1: state.selectionRect.y1 + ey,
        polygon: Array.isArray(state.selectionRect.polygon) ? state.selectionRect.polygon.map((p) => ({ x: p.x + ex, y: p.y + ey })) : state.selectionRect.polygon,
      };
    }
  }
  const activeWorldForRender = displayWorld();
  state.camera = clampCameraForView(state.camera, viewSize, activeWorldForRender);
  const viewportStartedAt = performance.now();
  state.viewportMap = getViewportMap(activeWorldForRender, state.camera, viewSize.width, viewSize.height, { light: !!options.fastTerrain });
  const viewportMs = performance.now() - viewportStartedAt;
  const hoverStartedAt = performance.now();
  state.hoverEntities = options.fastTerrain ? [] : buildHoverEntities(state.viewportMap);
  const hoverMs = performance.now() - hoverStartedAt;
  const drawStartedAt = performance.now();
  const renderBreakdown = drawMap(canvas, state.viewportMap, {
    mode: state.mode,
    showFeatures: state.showFeatures && !options.fastTerrain,
    showLabels: state.showLabels && !options.fastTerrain,
    showSeamDiagnostics: state.showSeamDiagnostics && !options.fastTerrain,
    continuousTerrain: !options.fastTerrain,
    fastTerrain: !!options.fastTerrain,
    zoom: state.zoom || 1,
  });
  const drawMs = performance.now() - drawStartedAt;
  applyCanvasZoom();
  if (state.selectionRect && dragState.mode !== "select") updateSelectionOverlayFromWorldRect();
  updateRenderDiagnostics(options, {
    viewportMs,
    hoverMs,
    drawMs,
    totalRenderMs: performance.now() - redrawStartedAt,
    renderBreakdown,
  });
  renderAdvancedData();
}

function init() {
  renderModeButtons();
  setToolMode("pan");

  generateMapButton?.addEventListener("click", regenerate);
  seedInput.addEventListener("change", regenerate);
  seedInput.addEventListener("keydown", (event) => {
    if (event.key === "Enter") regenerate();
  });

  generationTypeInput?.addEventListener("change", regenerate);
  patchTerrainTypeInput?.addEventListener("change", () => {
    discardPendingPatch({ redrawAfter: true });
    state.lastPatchResult = null;
    state.patchStatusMessage = "";
    resetPatchVariant({ update: false });
    updatePatchControls();
  });
  patchModeInput?.addEventListener("change", () => {
    discardPendingPatch({ redrawAfter: true });
    state.lastPatchResult = null;
    state.patchStatusMessage = "";
    updatePatchControls();
    renderAdvancedData();
  });
  patchVariantInput?.addEventListener("change", () => {
    state.patchStatusMessage = "";
    setPatchVariant(patchVariantInput.value);
  });
  patchVariantInput?.addEventListener("keydown", (event) => {
    if (event.key === "Enter") {
      setPatchVariant(patchVariantInput.value);
      generateSelectedPatch();
    }
  });
  generatePatchButton?.addEventListener("click", () => generateSelectedPatch("Patch preview"));
  alternativePatchButton?.addEventListener("click", generateAlternativePatch);
  applyPatchButton?.addEventListener("click", () => hideSelectionOverlay({ commitPreview: true }));
  discardPatchButton?.addEventListener("click", () => hideSelectionOverlay({ discardPreview: true }));
  clearPatchSelectionButton?.addEventListener("click", () => hideSelectionOverlay({ discardPreview: true }));
  cancelPatchButton?.addEventListener("click", () => cancelPatchGeneration());
  toolPanButton?.addEventListener("click", () => setToolMode("pan"));
  toolPatchButton?.addEventListener("click", () => setToolMode("patch"));
  copyImportantDataButton?.addEventListener("click", copyImportantDebugData);
  zoomInButton?.addEventListener("click", () => setZoomKeepingCenter((state.zoom || 1) * 1.2));
  zoomOutButton?.addEventListener("click", () => setZoomKeepingCenter((state.zoom || 1) / 1.2));
  zoomResetButton?.addEventListener("click", () => setZoomKeepingCenter(1));
  centerMapButton?.addEventListener("click", recenterMap);

  randomSeedButton.addEventListener("click", () => {
    seedInput.value = String(Math.floor(Math.random() * 9999999));
    regenerate();
  });

  showFeaturesInput.addEventListener("change", () => {
    state.showFeatures = showFeaturesInput.checked;
    redraw();
  });

  showLabelsInput.addEventListener("change", () => {
    state.showLabels = showLabelsInput.checked;
    redraw();
  });
  showSeamDiagnosticsInput?.addEventListener("change", () => {
    state.showSeamDiagnostics = showSeamDiagnosticsInput.checked;
    redraw({ fastTerrain: false, allowWorldExpand: false });
  });

  canvasShell?.setAttribute("tabindex", "0");
  canvas.addEventListener("contextmenu", (event) => event.preventDefault());
  canvas.addEventListener("wheel", handleCanvasWheel, { passive: false });
  canvas.addEventListener("pointerdown", handleMapPointerDown);
  canvas.addEventListener("pointermove", handleMapPointerMove);
  canvas.addEventListener("pointerup", handleMapPointerUp);
  canvas.addEventListener("pointercancel", handleMapPointerUp);
  canvas.addEventListener("mousemove", updateTooltip);
  canvas.addEventListener("mouseleave", () => {
    tooltipEl?.classList.remove("visible");
  });
  window.addEventListener("keydown", (event) => {
    if (event.key !== "Escape") return;
    if (state.patchBusy) {
      cancelPatchGeneration();
      event.preventDefault();
      return;
    }
    if (!state.selectionRect) return;
    hideSelectionOverlay({ discardPreview: true });
    event.preventDefault();
  });

  let resizeRaf = null;
  window.addEventListener("resize", () => {
    if (resizeRaf) cancelAnimationFrame(resizeRaf);
    resizeRaf = requestAnimationFrame(() => {
      resizeRaf = null;
      if (state.world) redraw({ allowWorldExpand: false });
      else applyCanvasZoom();
    });
  });

  updatePatchControls();
  renderAdvancedData();
  regenerate();
}

init();