export default {
  async fetch(request, env, ctx) {
    const url = new URL(request.url);
    if (url.pathname === '/stream') return streamPrices(request, env, ctx);
    if (url.pathname === '/api/fred') return fredMacro(env);
    if (url.pathname === '/api/news') return newsFinnhub(env);
    return new Response(getIndexHTML(), { headers: { 'content-type': 'text/html; charset=utf-8' } });
  }
};

/** SSE stream vers le navigateur; côté serveur on consomme le stream OANDA et on re‑émet. */
async function streamPrices(request, env, ctx){
  const account = env.OANDA_ACCOUNT;
  const token = env.OANDA_TOKEN;
  const isPractice = (env.OANDA_ENV||'practice').toLowerCase()==='practice';
  if(!account || !token){
    return json({ error: 'Manque OANDA_ACCOUNT ou OANDA_TOKEN' }, 500);
  }
  const host = isPractice ? 'stream-fxpractice.oanda.com' : 'stream-fxtrade.oanda.com';
  const endpoint = `https://${host}/v3/accounts/${account}/pricing/stream?instruments=XAU_USD`;

  const encoder = new TextEncoder();
  const { readable, writable } = new TransformStream();
  const writer = writable.getWriter();

  // Headers SSE
  const headers = {
    'content-type': 'text/event-stream; charset=utf-8',
    'cache-control': 'no-cache, no-transform',
    'connection': 'keep-alive',
    'access-control-allow-origin': '*'
  };

  // Envoi ping toutes 25s pour garder la connexion ouverte côté client
  const ping = () => writer.write(encoder.encode(`event: ping\ndata: {}\n\n`));
  const pingId = setInterval(ping, 25000);
  ctx.waitUntil((async()=>{ while(true){ await new Promise(r=>setTimeout(r, 60000)); } })());

  // Connecte au stream OANDA
  (async () => {
    try{
      const oandaRes = await fetch(endpoint, { headers: { 'Authorization': `Bearer ${token}` } });
      if(!oandaRes.ok) {
        await writer.write(encoder.encode(`event: error\ndata: ${JSON.stringify({status:oandaRes.status})}\n\n`));
        clearInterval(pingId); writer.close(); return;
      }
      const reader = oandaRes.body.getReader();
      let buffer = '';
      while(true){
        const {done, value} = await reader.read();
        if(done) break;
        buffer += new TextDecoder().decode(value);
        // OANDA envoie des lignes JSON séparées par \n
        let idx;
        while((idx = buffer.indexOf('\n')) >= 0){
          const line = buffer.slice(0, idx).trim();
          buffer = buffer.slice(idx+1);
          if(!line) continue;
          try{
            const msg = JSON.parse(line);
            if(msg.type === 'PRICE'){
              const bid = Number(msg.bids?.[0]?.price);
              const ask = Number(msg.asks?.[0]?.price);
              const mid = (bid && ask) ? (bid+ask)/2 : null;
              const out = { t: msg.time, bid, ask, mid };
              await writer.write(encoder.encode(`data: ${JSON.stringify(out)}\n\n`));
            }
          }catch(e){ /* ignore parse errors */ }
        }
      }
    }catch(e){
      await writer.write(encoder.encode(`event: error\ndata: ${JSON.stringify({error:String(e)})}\n\n`));
    } finally {
      clearInterval(pingId);
      writer.close();
    }
  })();

  return new Response(readable, { headers });
}

/** Proxy simple: dernières obs FRED pour DXY proxy (DTWEXM), DGS10, T10YIE */
async function fredMacro(env){
  if(!env.FRED_KEY) return json({ error:'Missing FRED_KEY' }, 500);
  const base = 'https://api.stlouisfed.org/fred/series/observations';
  const last2 = async(series)=>{
    const url = `${base}?series_id=${series}&api_key=${env.FRED_KEY}&file_type=json&sort_order=desc&limit=2`;
    const r = await fetch(url); const j = await r.json();
    const obs = (j.observations||[]).filter(o=>o.value!=='.').slice(0,2).map(o=>({date:o.date, v: parseFloat(o.value)}));
    return { last: obs[0]||null, prev: obs[1]||null };
  };
  const [dxy, dgs10, t10yie] = await Promise.all([
    last2('DTWEXM'), last2('DGS10'), last2('T10YIE')
  ]);
  return json({ dxy, dgs10, t10yie });
}

/** News Finnhub filtrées "gold" */
async function newsFinnhub(env){
  if(!env.FINNHUB_KEY) return json({items:[]});
  const r = await fetch(`https://finnhub.io/api/v1/news?category=general&token=${env.FINNHUB_KEY}`);
  const arr = await r.json();
  const KW = ['gold','xau','bullion','precious','comex','silver'];
  const items = (arr||[]).filter(n=>{
    const t = `${n.headline} ${n.summary}`.toLowerCase();
    return KW.some(k=>t.includes(k));
  }).slice(0,12).map(n=>({headline:n.headline,url:n.url,summary:n.summary,source:n.source,datetime:n.datetime}));
  return json({ items });
}

function json(obj, status=200){
  return new Response(JSON.stringify(obj), { status, headers: { 'content-type':'application/json', 'access-control-allow-origin':'*' }});
}

/** UI minimaliste avec Chart.js + SSE */
function getIndexHTML(){
  return `<!doctype html>
<html lang="fr">
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1" />
  <title>Speecy Gold — Temps réel</title>
  <meta name="description" content="Prix XAUUSD temps réel (OANDA), macro FRED, news or." />
  <script src="https://cdn.tailwindcss.com"></script>
  <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
  <style>.glass{backdrop-filter:saturate(180%) blur(8px); background:rgba(17,17,17,.6)}</style>
</head>
<body class="min-h-screen bg-neutral-950 text-neutral-100">
<header class="sticky top-0 z-10 border-b border-neutral-800 glass">
  <div class="max-w-6xl mx-auto px-4 py-3 flex items-center justify-between">
    <div class="flex items-center gap-2"><div class="w-8 h-8 rounded-xl bg-yellow-500/20 border border-yellow-500/40 grid place-items-center">💛</div><div class="font-semibold">Speecy Gold – Temps réel</div></div>
    <div class="text-xs text-neutral-400">Dernière tick: <span id="lastT">—</span></div>
  </div>
</header>
<main class="max-w-6xl mx-auto px-4 py-6 space-y-6">
  <section class="grid md:grid-cols-3 gap-4">
    <div class="p-4 rounded-2xl bg-neutral-900 border border-neutral-800">
      <div class="text-neutral-400 text-sm">XAU/USD (OANDA stream)</div>
      <div class="mt-2 flex items-end gap-3">
        <div class="text-3xl font-bold" id="px">—</div>
        <div id="spread" class="text-sm text-neutral-400">—</div>
      </div>
      <div class="text-[11px] text-neutral-500 mt-2">Flux practice en temps réel (jusqu'à ~4 updates/s).</div>
    </div>
    <div class="p-4 rounded-2xl bg-neutral-900 border border-neutral-800">
      <div class="text-neutral-400 text-sm">Indicateurs clés</div>
      <div class="grid grid-cols-3 gap-3 mt-2 text-sm">
        <div><div class="text-neutral-400">DXY*</div><div id="dxy" class="font-semibold">—</div></div>
        <div><div class="text-neutral-400">US10Y</div><div id="us10" class="font-semibold">—</div></div>
        <div><div class="text-neutral-400">10Y Réel</div><div id="real10" class="font-semibold">—</div></div>
      </div>
      <div class="text-[11px] text-neutral-500 mt-2">*DTWEXM comme proxy.</div>
    </div>
    <div class="p-4 rounded-2xl bg-neutral-900 border border-neutral-800">
      <div class="text-neutral-400 text-sm">Biais (heuristique)</div>
      <div id="bias" class="mt-2 text-2xl font-bold">—</div>
    </div>
  </section>
  <section class="p-4 rounded-2xl bg-neutral-900 border border-neutral-800">
    <div class="flex items-center justify-between mb-3"><h2 class="text-lg font-semibold">Intraday – ticks (mid)</h2>
    <button id="reset" class="px-3 py-1.5 text-sm rounded-xl bg-yellow-500/20 border border-yellow-500/30 hover:bg-yellow-500/30">Reset</button></div>
    <canvas id="chart" height="120"></canvas>
  </section>
  <section class="p-4 rounded-2xl bg-neutral-900 border border-neutral-800">
    <div class="flex items-center justify-between mb-3"><h2 class="text-lg font-semibold">News “gold”</h2>
    <a href="#" class="text-xs text-neutral-400" id="src">source: Finnhub</a></div>
    <div id="news" class="grid md:grid-cols-2 gap-3"></div>
  </section>
  <footer class="py-8 text-center text-xs text-neutral-500">© Speecy Trading • Démo éducative</footer>
</main>
<script>
const $ = (id)=>document.getElementById(id);
let chart, dataX=[], dataY=[];
function initChart(){
  const ctx = document.getElementById('chart');
  chart = new Chart(ctx, { type:'line', data:{ labels:dataX, datasets:[{ label:'XAUUSD mid', data:dataY, tension:.25 }]}, options:{ plugins:{legend:{display:false}}, scales:{x:{display:false}, y:{display:true}} }});
}
function pushTick(ts, mid){ dataX.push(ts); dataY.push(mid); if(dataX.length>600){ dataX.shift(); dataY.shift(); } chart.update('none'); }

function startSSE(){
  const es = new EventSource('/stream');
  es.onmessage = (e)=>{
    try{ const m = JSON.parse(e.data); if(!m) return; const mid = m.mid??((m.bid+m.ask)/2); if(!mid) return; $('px').textContent = mid.toFixed(2); $('lastT').textContent = new Date(m.t).toLocaleTimeString(); if(m.bid && m.ask){ $('spread').textContent = `spread ${(m.ask-m.bid).toFixed(2)}`; } pushTick(new Date(m.t).toLocaleTimeString(), mid); }catch(err){}
  };
  es.addEventListener('error', ()=>{ console.log('SSE error'); });
}

async function loadMacro(){
  try{ const r = await fetch('/api/fred'); const j = await r.json(); const dxy=j.dxy?.last?.v; const us10=j.dgs10?.last?.v; const be=j.t10yie?.last?.v; const real = (us10!=null && be!=null)? (us10-be): null; if(dxy!=null) $('dxy').textContent=dxy.toFixed(2); if(us10!=null) $('us10').textContent=us10.toFixed(2)+'%'; if(real!=null) $('real10').textContent=real.toFixed(2)+'%'; const bias = ((j.dxy?.prev && dxy<j.dxy.prev.v) && (j.dgs10?.prev && j.t10yie?.prev && ( (j.dgs10.prev.v-j.t10yie.prev.v) > real ))) ? 'Haussier' : 'Neutre'; $('bias').textContent=bias; $('bias').className = 'mt-2 text-2xl font-bold ' + (bias==='Haussier'?'text-green-400':'text-neutral-100'); }catch(e){}
}
async function loadNews(){
  try{ const r = await fetch('/api/news'); const j = await r.json(); const el=$('news'); el.innerHTML=''; (j.items||[]).forEach(n=>{const a=document.createElement('a'); a.href=n.url; a.target='_blank'; a.className='block p-4 rounded-xl border border-neutral-800 bg-neutral-950 hover:bg-neutral-900'; a.innerHTML=`<div class='text-xs text-neutral-400'>${new Date(n.datetime*1000).toLocaleString()}</div><div class='mt-1 font-semibold'>${n.headline}</div><p class='text-sm text-neutral-300 mt-1'>${n.summary||''}</p>`; el.appendChild(a); }); }catch(e){}
}
$('reset').addEventListener('click', ()=>{ dataX=[]; dataY=[]; chart.update(); });
initChart(); startSSE(); loadMacro(); loadNews(); setInterval(loadMacro, 60_000);
</script>
</body></html>`;
}