// Minimal frontend to create/join a game and render a static board using chess_maestro pieces
const q = s => document.querySelector(s);

function showLobby() {
  q('#lobby').classList.remove('hidden');
  q('#board-section')?.classList?.add('hidden');
}

function showBoard(gameId, role) {
  q('#lobby').classList.add('hidden');
  q('#board-section')?.classList?.remove('hidden');
  q('#game-id').textContent = gameId;
  q('#player-role').textContent = role;
  renderBoard(role === 'white');
}

q('#create-btn').addEventListener('click', () => {
  console.log('[frontend] create-btn clicked');
  const id = 'game-' + Math.random().toString(36).slice(2,9);
  const pass = q('#create-pass').value;
  const name = q('#create-name').value || id;
  // minimal create: we don't prompt for a pseudo; server will assign an internal id
  const nick = 'player';
  const colorChoice = 'random';
  const game = { id, name, pass: pass || null, owner: 'you', created: Date.now(), players: [{ id: 'p-' + Math.random().toString(36).slice(2,6), nickname: nick, colorChoice, colorAssigned: null }], started: false };

  // try backend first (explicit host). If it fails, save locally and redirect to waiting page.
  // include a neutral ownerNickname so backend creates the owner player, but we do not surface any pseudo in the UI
  fetch('http://localhost:4000/api/create', { method: 'POST', headers: {'Content-Type':'application/json'}, body: JSON.stringify({name, pass, ownerNickname: nick, ownerColorChoice: colorChoice}) })
    .then(r => { console.log('[frontend] backend /api/create response', r.status); if(!r.ok) throw new Error('no api'); return r.json(); })
    .then(resp => { console.log('[frontend] created (backend)', resp); /* backend now returns { ok: true, game, player } for the owner */
      if(resp.player && resp.player.id){ sessionStorage.setItem(`playerId:${resp.game.id}`, resp.player.id); }
      alert('Partie créée: ' + (resp.game.name || 'Partie')); window.location.href = `waiting.html?game=${resp.game.id}`; })
    .catch((err) => {
      console.warn('[frontend] backend create failed, saving locally and redirecting', err && err.message);
      // save to localStorage so waiting page can pick it up
      const all = JSON.parse(localStorage.getItem('games') || '[]');
      all.push(game);
      localStorage.setItem('games', JSON.stringify(all));
      alert('Partie créée localement: ' + (game.name || 'Partie'));
      window.location.href = `waiting.html?game=${game.id}`;
    });
});

q('#show-list-btn').addEventListener('click', () => {
  const list = q('#games-list');
  list.classList.toggle('hidden');
  renderGameList();
});

function saveGame(game){
  const all = JSON.parse(localStorage.getItem('games') || '[]');
  all.push(game);
  localStorage.setItem('games', JSON.stringify(all));
}

function renderGameList(){
  const ul = q('#games-ul');
  ul.innerHTML = '';
  console.log('[frontend] renderGameList called');
  // prefer backend host in dev
  fetch('http://localhost:4000/api/list')
    .then(r => { if(!r.ok) throw new Error('no remote api'); return r.json(); })
    .then(all => { if(!all || all.length === 0){ ul.innerHTML = '<li>Aucune partie disponible</li>'; return; } all.forEach(g => renderGameListItem(ul, g)); })
    .catch(() => {
      // try same-origin then localStorage
      fetch('/api/list')
        .then(r => { if(!r.ok) throw new Error('no local api'); return r.json(); })
        .then(all => { if(!all || all.length === 0){ ul.innerHTML = '<li>Aucune partie disponible</li>'; return; } all.forEach(g => renderGameListItem(ul, g)); })
        .catch(() => {
          const all = JSON.parse(localStorage.getItem('games') || '[]');
          if(all.length === 0){ ul.innerHTML = '<li>Aucune partie disponible</li>'; return; }
          all.forEach(g => renderGameListItem(ul, g));
        });
    });
}

// Socket: listen for global games-list updates from backend to refresh lobby list live
if(typeof io !== 'undefined'){
  try{
    const sock = io('http://localhost:4000', { transports: ['websocket', 'polling'] });
    sock.on('connect', () => { console.log('lobby socket connected', sock.id); });
    sock.on('games-list', (list) => { console.log('games-list event received', list); try { renderGameList(); } catch(e){} });
    sock.on('connect_error', (e) => { console.warn('lobby socket connect error', e); });
  }catch(e){ console.warn('failed to init lobby socket', e); }
}

function renderGameListItem(ul, g){
  const li = document.createElement('li');
  // display only human-friendly name; avoid showing internal ids
  li.textContent = g.name || 'Partie';

  // detect if this client already joined this game (we store playerId in sessionStorage)
  const storedPlayerId = sessionStorage.getItem(`playerId:${g.id}`);
  // If we have a stored player id but the server-side game no longer contains that player,
  // cleanup the sessionStorage entry (it means the player was removed / left).
  let alreadyJoined = false;
  if (storedPlayerId) {
    const playerStillInGame = (g.players || []).some(p => p.id === storedPlayerId);
    if (!playerStillInGame) {
      // stale stored id: remove it
      sessionStorage.removeItem(`playerId:${g.id}`);
    } else {
      alreadyJoined = true;
    }
  }

  if(alreadyJoined){
    const span = document.createElement('span');
    span.textContent = ' — Vous êtes dans cette partie';
    span.style.marginLeft = '8px';
    li.appendChild(span);
  } else {
    const btn = document.createElement('button');
    btn.textContent = 'Rejoindre';
    btn.addEventListener('click', () => {
      console.log('[frontend] join clicked for', g.id);
      if(g.pass){ const entered = prompt('Mot de passe pour rejoindre la partie'); if(entered !== g.pass){ alert('Mot de passe incorrect'); return; } }
      const nick = prompt('Ton pseudo') || 'Player';
      const payload = { id: g.id, pass: g.pass, nickname: nick };

      // prefer backend host first
      fetch('http://localhost:4000/api/join', { method: 'POST', headers: {'Content-Type':'application/json'}, body: JSON.stringify(payload) })
        .then(r => { if(!r.ok) throw new Error('join failed'); return r.json(); })
    .then(resp => { if(resp && resp.player && resp.player.id){ sessionStorage.setItem(`playerId:${g.id}`, resp.player.id); } window.location.href = `waiting.html?game=${g.id}`; })
        .catch(() => {
          fetch('/api/join', { method: 'POST', headers: {'Content-Type':'application/json'}, body: JSON.stringify(payload) })
            .then(r => { if(!r.ok) throw new Error('join failed'); return r.json(); })
            .then(() => { window.location.href = `waiting.html?game=${g.id}`; })
            .catch(() => { saveGame(g); window.location.href = `waiting.html?game=${g.id}`; });
        });

    });

    li.appendChild(btn);
  }

  ul.appendChild(li);
}

q('#leave-btn')?.addEventListener('click', () => showLobby());

q('#flip-btn')?.addEventListener('click', () => { const board = q('#board-container'); board.classList.toggle('flipped'); });

function renderBoard(asWhite=true) {
  const container = q('#board-container');
  if(!container) return;
  container.innerHTML = '';
  const board = document.createElement('div');
  board.className = 'board';
  if (!asWhite) board.classList.add('flipped');

  for (let r = 0; r < 8; r++) {
    const row = document.createElement('div');
    row.className = 'row';
    for (let c = 0; c < 8; c++) {
      const cell = document.createElement('div');
      cell.className = 'cell';
      const piece = document.createElement('img');
      piece.className = 'piece';
      if (r === 1) piece.src = 'assets/chess-pieces/chess_maestro_bw/wP.svg';
      else if (r === 6) piece.src = 'assets/chess-pieces/chess_maestro_bw/bP.svg';
      else piece.style.display = 'none';
      cell.appendChild(piece);
      row.appendChild(cell);
    }
    board.appendChild(row);
  }

  container.appendChild(board);
}

// initial view
showLobby();

// waiting room helpers
let pollInterval = null;
function showWaiting(game){
  q('#lobby').classList.add('hidden');
  q('#board-section')?.classList?.add('hidden');
  q('#lobby-waiting').classList.remove('hidden');
  // show the game name instead of internal id
  q('#wait-game-id').textContent = game.name || '';
  renderWaitingPlayers(game.players || []);
}

function renderWaitingPlayers(players){
  const ul = q('#wait-players'); ul.innerHTML = '';
  if(!players || players.length === 0) ul.innerHTML = '<li>Aucun joueur</li>';
  (players||[]).forEach(p => { const li = document.createElement('li'); li.textContent = `${p.nickname} (${p.colorAssigned || p.colorChoice})`; ul.appendChild(li); });
}

function startPolling(gameId){
  if(pollInterval) clearInterval(pollInterval);
  pollInterval = setInterval(() => {
    fetch(`/api/game/${gameId}`).then(r => { if(!r.ok) throw new Error('no api'); return r.json(); }).then(g => {
      renderWaitingPlayers(g.players || []);
      if(g.started){ clearInterval(pollInterval); q('#lobby-waiting').classList.add('hidden'); showBoard(g.id, 'white'); }
    }).catch(() => {
      fetch(`http://localhost:4000/api/game/${gameId}`).then(r => r.json()).then(g => { renderWaitingPlayers(g.players || []); if(g.started){ clearInterval(pollInterval); q('#lobby-waiting').classList.add('hidden'); showBoard(g.id, 'white'); } }).catch(()=>{});
    });
  }, 1000);
}

q('#start-btn')?.addEventListener('click', () => {
  const id = q('#wait-game-id').textContent;
  fetch('/api/start', { method: 'POST', headers: {'Content-Type':'application/json'}, body: JSON.stringify({ id }) })
    .then(r => { if(!r.ok) throw new Error('start failed'); return r.json(); })
    .then(() => alert('Partie démarrée'))
    .catch(() => { fetch('http://localhost:4000/api/start', { method: 'POST', headers: {'Content-Type':'application/json'}, body: JSON.stringify({ id }) }).then(()=>alert('Partie démarrée')).catch(()=>alert('Impossible de démarrer la partie')); });
});

q('#back-to-lobby')?.addEventListener('click', () => { if(pollInterval) clearInterval(pollInterval); q('#lobby-waiting').classList.add('hidden'); showLobby(); });