'use strict';

function deploymentBase(value){
  const raw=String(value||'').trim();
  if(!raw)return null;
  const base=new URL(raw.endsWith('/')?raw:`${raw}/`);
  if(!['http:','https:'].includes(base.protocol))throw new Error('LinkField public URL must use HTTP or HTTPS');
  return base;
}

async function fetchChecked(url,{accept='application/json',timeoutMs=10_000}={}){
  const response=await fetch(url,{headers:{accept},signal:AbortSignal.timeout(timeoutMs)});
  return response;
}

async function checkPublicDeployment(publicUrl,{appVersion,timeoutMs=10_000}={}){
  const base=deploymentBase(publicUrl);if(!base)return null;
  const pageUrl=new URL('',base),apiUrl=new URL('api/cloud/status',base),bridgeUrl=new URL('api-bridge.php?path=/api/cloud/status',base);
  const page=await fetchChecked(pageUrl,{accept:'text/html',timeoutMs}),pageBody=await page.text();
  if(!page.ok||!pageBody.includes('LinkField'))throw new Error(`Public page failed at ${pageUrl.href}: HTTP ${page.status}`);
  const disclosed=page.headers.get('server')||'';if(/\//.test(disclosed))throw new Error(`Public server discloses a detailed version: ${disclosed}`);
  for(const relative of ['server.js','package.json','scripts/service-control.js','.linkfield-deployment.json']){
    const url=new URL(relative,base),response=await fetchChecked(url,{accept:'text/plain',timeoutMs});
    if(![403,404].includes(response.status))throw new Error(`Private deployment file is public at ${url.href}: HTTP ${response.status}`);
    await response.body?.cancel().catch(()=>{});
  }
  const results=[];
  for(const [kind,url] of [['API',apiUrl],['PHP bridge',bridgeUrl]]){
    const response=await fetchChecked(url,{timeoutMs}),body=await response.json().catch(()=>({}));
    if(!response.ok||body?.available!==true||body?.appVersion!==appVersion)throw new Error(`Public ${kind} failed at ${url.href}: HTTP ${response.status}`);
    if(kind==='PHP bridge'&&response.headers.get('x-linkfield-bridge')!=='php')throw new Error(`Public PHP bridge did not identify itself at ${url.href}`);
    results.push({kind,url:url.href,status:response.status});
  }
  return{base:base.href,page:pageUrl.href,api:results[0].url,bridge:results[1].url};
}

module.exports=Object.freeze({deploymentBase,checkPublicDeployment});