import { MAP_H, MAP_W, indexOf, inside } from "./grid.js";
import { hash2 } from "./random.js";

// Default and custom place-name resources.
// Edit only this file to change generated names or override individual IDs.

export const NAME_PARTS = {
  // May appear only at the beginning of a name.
  prefixOnly: ["大", "小", "新", "古", "浅", "深", "上", "下", "東", "西", "南", "北", "中", "本", "広", "元", "奥", "前", "高", "長", "丸", "一", "壱", "二", "三", "四", "五", "六", "七", "八", "九", "十", "五十", "百", "千", "万", "阿", "佐々", "代々", "千代", "宇", "伊", "牟", "美",],

  // Generic morphemes that may appear at the beginning or in the middle.
  free: [
    //pattern
"青", "白", "黒", "赤", "藍",

     //nature
"川", "山", "森", "松", "竹", "梅", "柳", "栃", "橘", "柏", "樫", "麻", "桜", "岡", "木", "林", "森", "根", "葉", "葦", "日", "月", "君",
"野", "尾", "旭", "朝", "霧",

    //objects
"畠", "秦", "幡", "井", "真", "田", "井", "口", "関", "矢", "手", "戸", "庄", "屋", "土", "鋸", "琴", "笙", "彦", "比", "碑", "多", "", "",
    //others
"由", "志", "成", "幸", "徳", "甲", "由", "和", "清", "弘", "保", "徳", "福", "富", "住", "幸", "弥", "住", "生", "昌", "相", "香", "吉", "𠮷", "佐", "多", "保", "加"
  ],

  // May appear only at the end of a name.
  suffixOnly: ["宿", "口", "摩", "磨", "潟", "茂"],

  // Context-aware morphemes that may appear at the beginning or in the middle.
  contextFree: {
    coastal: ["浜", "浦", "津", "湊", "潮", "磯", "海", "島", "磯", "渚", "潮", "汐"],
    river: ["瀬", "川", "橋", "渡", "沢", "淵", "沼", "堀"],
    plain: ["原", "野", "田", "畠", "里", "平", "牧", "塚"],
    mountain: ["山", "谷", "沢", "峰", "尾", "久保", "迫", "岳"],
    historic: ["城", "館", "宮", "寺", "社", "陣", "府", "町"],
    suburban: [],
  },

  // Context-aware morphemes that may appear only at the end of a name.
  contextSuffixes: {
    coastal: ["浜", "湊", "灘", "浦", "津", "崎", "嶋"],
    river: ["川", "瀬", "橋", "渡", "沼", "沢"],
    plain: ["原", "野", "田", "里", "村", "平"],
    mountain: ["谷", "峡", "尾根", "山", "沢", "麓"],
    historic: ["城", "通", "館", "宮", "町"],
    suburban: ["丘", "台", "野", "原", "新町", "ヶ丘"],
  },
};

export const NAME_PROBABILITIES = {
  prefixOnly: 0.36,
  contextFreeAsMain: 0.34,
  additionalContextFree: 0.22,
  secondFree: 0.18,
  finalContextSuffix: 0.10,
  finalSuffixOnly: 0.50,
  finalFree: 0.20,
  twoCharacter: 0.80,
};

export const CONTEXT_SUFFIXES = NAME_PARTS.contextSuffixes;

export const CUSTOM_NAMES = {
  // "city-0": "Aohara",
  // "port-0": "Shirahama",
  // "castle-0": "Kurono",
};

function isNearSea(x, y, sea, radius = 3) {
  if (!sea) return false;
  for (let dy = -radius; dy <= radius; dy++) {
    for (let dx = -radius; dx <= radius; dx++) {
      const nx = x + dx;
      const ny = y + dy;
      if (inside(nx, ny) && sea[indexOf(nx, ny)]) return true;
    }
  }
  return false;
}

function boundedIndex(entity) {
  return indexOf(Math.max(0, Math.min(MAP_W - 1, entity.x)), Math.max(0, Math.min(MAP_H - 1, entity.y)));
}

function chooseNameContext(entity, fields) {
  const kind = String(entity.kind || "").toLowerCase();
  const i = boundedIndex(entity);
  const coastal = (fields?.coastalLowland?.[i] || 0) > 0.35 || isNearSea(entity.x, entity.y, fields?.sea);
  const river = (fields?.river?.[i] || 0) > 0.35 || (fields?.valleyField?.[i] || 0) > 0.42;
  const plain = (fields?.plain?.[i] || 0) > 0.48 || (fields?.agriculture?.[i] || 0) > 0.46 || (fields?.basinField?.[i] || 0) > 0.35;
  const mountain = (fields?.elevation?.[i] || 0) > 0.52 || (fields?.slope?.[i] || 0) > 0.35 || (fields?.ridgeField?.[i] || 0) > 0.42;

  if (kind.includes("port") || kind.includes("harbor") || entity.portClass) return "coastal";
  if (kind.includes("crossing") || kind.includes("bridge")) return "river";
  if (kind.includes("pass") || kind.includes("mountain")) return "mountain";
  if (kind.includes("castle") || kind.includes("market")) return "historic";
  if (kind.includes("new town") || kind.includes("satellite")) return "suburban";
  if (coastal && !mountain) return "coastal";
  if (river) return "river";
  if (mountain && !plain) return "mountain";
  if (plain) return "plain";
  return "plain";
}

export function chooseNameSuffixPool(entity, fields) {
  const context = chooseNameContext(entity, fields);
  return NAME_PARTS.contextSuffixes[context] || NAME_PARTS.contextSuffixes.plain;
}

function chooseContextFreePool(entity, fields, nameParts) {
  const context = chooseNameContext(entity, fields);
  return nameParts.contextFree?.[context] || nameParts.contextFree?.plain || nameParts.free || [""];
}

function pick(pool, seed, n, salt) {
  if (!pool?.length) return "";
  const index = Math.floor(hash2(n + salt * 101, seed + salt * 1009, seed + n * 37 + salt) * pool.length) % pool.length;
  return pool[index];
}

function chance(seed, n, salt, probability) {
  return hash2(n + salt * 173, seed + salt * 811, seed + n * 43 + salt) < probability;
}

function characterLength(value) {
  return Array.from(String(value || "")).length;
}

function oneCharacterPool(pool, fallbackPool = pool) {
  const filtered = (pool || []).filter((part) => characterLength(part) === 1);
  return filtered.length ? filtered : (fallbackPool || [""]);
}

function appendPart(parts, part) {
  if (!part) return;
  const previous = parts[parts.length - 1] || "";
  if (previous && (previous === part || previous.endsWith(part) || part.startsWith(previous))) return;
  parts.push(part);
}

function appendFinalPart(parts, part, fallbackPool, seed, n, salt) {
  let finalPart = part;
  if (finalPart && parts.some((existing) => existing === finalPart || existing.endsWith(finalPart))) {
    finalPart = pick(fallbackPool, seed, n, salt + 1);
  }
  appendPart(parts, finalPart);
}

function trimNameParts(parts) {
  if (parts.length <= 3) return parts;
  return [parts[0], ...parts.slice(-2)];
}

export function contextualDefaultName(seed, id, entity, nameParts = NAME_PARTS, fields, attempt = 0) {
  const prefixKey = id.split("-")[0];
  const n = Number(id.split("-")[1] || 0) + attempt * 997;

  const prefixOnly = nameParts.prefixOnly || nameParts.prefixes || [""];
  const free = nameParts.free || nameParts.infixes || [""];
  const suffixOnly = nameParts.suffixOnly || nameParts.suffixes || [""];
  const contextFree = chooseContextFreePool(entity, fields, nameParts);
  const contextSuffixes = chooseNameSuffixPool(entity, fields);
  const probabilities = nameParts.probabilities || NAME_PROBABILITIES;

  if (chance(seed, n, 7 + prefixKey.length, probabilities.twoCharacter ?? 0.80)) {
    const onePrefixOnly = oneCharacterPool(prefixOnly);
    const oneFree = oneCharacterPool(free);
    const oneSuffixOnly = oneCharacterPool(suffixOnly, oneFree);
    const oneContextFree = oneCharacterPool(contextFree, oneFree);
    const oneContextSuffixes = oneCharacterPool(contextSuffixes, oneSuffixOnly);

    const usePrefix = chance(seed, n, 11 + prefixKey.length, probabilities.prefixOnly);
    const useContextAsMain = chance(seed, n, 13 + prefixKey.length, probabilities.contextFreeAsMain ?? probabilities.contextFree ?? 0.34);
    const firstPart = usePrefix
      ? pick(onePrefixOnly, seed, n, 101)
      : pick(useContextAsMain ? oneContextFree : oneFree, seed, n, useContextAsMain ? 211 : 223);

    const finalContextProbability = probabilities.finalContextSuffix ?? 0.10;
    const finalSuffixProbability = probabilities.finalSuffixOnly ?? 0.50;
    const finalFreeProbability = probabilities.finalFree ?? Math.max(0, 1 - finalContextProbability - finalSuffixProbability);
    const finalTotal = Math.max(0.0001, finalContextProbability + finalSuffixProbability + finalFreeProbability);
    const finalRoll = hash2(n + prefixKey.length * 23, seed + n * 37, seed + 7919);
    const contextThreshold = finalContextProbability / finalTotal;
    const suffixThreshold = (finalContextProbability + finalSuffixProbability) / finalTotal;
    let finalPart;
    if (finalRoll < contextThreshold) {
      finalPart = pick(oneContextSuffixes, seed, n, 503);
    } else if (finalRoll < suffixThreshold) {
      finalPart = pick(oneSuffixOnly, seed, n, 509);
    } else {
      finalPart = pick(oneFree, seed, n, 521);
    }
    if (finalPart === firstPart) finalPart = pick(oneSuffixOnly, seed, n, 601);
    if (finalPart === firstPart) finalPart = pick(oneFree, seed, n, 607);
    return `${firstPart || pick(oneFree, seed, n, 613)}${finalPart || pick(oneSuffixOnly, seed, n, 617)}`;
  }

  const parts = [];

  if (chance(seed, n, 11 + prefixKey.length, probabilities.prefixOnly)) {
    appendPart(parts, pick(prefixOnly, seed, n, 101));
  }

  const useContextAsMain = chance(seed, n, 13 + prefixKey.length, probabilities.contextFreeAsMain ?? probabilities.contextFree ?? 0.34);
  appendPart(parts, pick(useContextAsMain ? contextFree : free, seed, n, useContextAsMain ? 211 : 223));

  if (!useContextAsMain && chance(seed, n, 17 + prefixKey.length, probabilities.additionalContextFree ?? probabilities.contextFree ?? 0.22)) {
    appendPart(parts, pick(contextFree, seed, n, 307));
  }

  if (chance(seed, n, 19 + prefixKey.length, probabilities.secondFree)) {
    appendPart(parts, pick(free, seed, n, 401));
  }

  const finalRoll = hash2(n + prefixKey.length * 23, seed + n * 37, seed + 7919);
  let finalPart;
  const finalContextProbability = probabilities.finalContextSuffix ?? 0.30;
  const finalSuffixProbability = probabilities.finalSuffixOnly ?? 0.50;
  const finalFreeProbability = probabilities.finalFree ?? Math.max(0, 1 - finalContextProbability - finalSuffixProbability);
  const finalTotal = Math.max(0.0001, finalContextProbability + finalSuffixProbability + finalFreeProbability);
  const contextThreshold = finalContextProbability / finalTotal;
  const suffixThreshold = (finalContextProbability + finalSuffixProbability) / finalTotal;
  if (finalRoll < contextThreshold) {
    finalPart = pick(contextSuffixes, seed, n, 503);
  } else if (finalRoll < suffixThreshold) {
    finalPart = pick(suffixOnly, seed, n, 509);
  } else {
    finalPart = pick(free, seed, n, 521);
  }
  appendFinalPart(parts, finalPart, suffixOnly, seed, n, 601);

  const name = trimNameParts(parts).join("");
  return name || pick(suffixOnly, seed, n, 601) || "原";
}