import { init as initScene, setPaintings } from '/static/scene.js';

// ── State ─────────────────────────────────────────────────────────────────────
const state = {
  userId:      localStorage.getItem('dm_user') || '',
  lastSketch:  null,
  lastDream:   null,
  activePanel: null,
};

// ── API helper ────────────────────────────────────────────────────────────────
async function api(path, body) {
  const r = await fetch(path, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(body),
  });
  return r.json();
}

// ── Boot ──────────────────────────────────────────────────────────────────────
document.addEventListener('DOMContentLoaded', async () => {
  initScene(document.getElementById('museum-canvas'), openDreamModal);

  if (state.userId) _applyAuth(state.userId);

  await _refreshMuseum();

  _initHUD();
  _initAuth();
  _initDrawCanvas();
  _initControls();
  _initModal();
  _initSaveBtns();
});

// ── Museum ────────────────────────────────────────────────────────────────────
async function _refreshMuseum() {
  const data = await api('/gallery/public', { limit: 12, offset: 0 });
  if (data.ok) setPaintings(data.dreams);
}

// ── HUD / panels ──────────────────────────────────────────────────────────────
function _initHUD() {
  document.getElementById('btn-create').addEventListener('click',    () => _openPanel('create'));
  document.getElementById('btn-my-gallery').addEventListener('click', () => _openPanel('gallery'));
  document.getElementById('close-create').addEventListener('click',   () => _openPanel(null));
  document.getElementById('close-gallery').addEventListener('click',  () => _openPanel(null));
}

function _openPanel(name) {
  if (state.activePanel) {
    document.getElementById(`panel-${state.activePanel}`).classList.remove('open');
  }
  state.activePanel = name;
  const canvas = document.getElementById('museum-canvas');

  if (name) {
    const panel = document.getElementById(`panel-${name}`);
    panel.classList.remove('hidden');
    requestAnimationFrame(() => panel.classList.add('open'));
    canvas.classList.add('dimmed');
    document.getElementById('room-hint').classList.add('hidden');
    if (name === 'gallery') _loadUserGallery();
  } else {
    canvas.classList.remove('dimmed');
    document.getElementById('room-hint').classList.remove('hidden');
  }
}

// Hide panel after slide-out transition ends
document.addEventListener('transitionend', e => {
  const el = e.target;
  if (el.classList.contains('side-panel') && !el.classList.contains('open')) {
    el.classList.add('hidden');
  }
});

// ── Auth ──────────────────────────────────────────────────────────────────────
function _initAuth() {
  const input = document.getElementById('auth-input');
  const btn   = document.getElementById('auth-btn');
  btn.addEventListener('click', () => { const v = input.value.trim(); if (v) _applyAuth(v); });
  input.addEventListener('keydown', e => { if (e.key === 'Enter') btn.click(); });
}

function _applyAuth(name) {
  state.userId = name;
  localStorage.setItem('dm_user', name);

  document.getElementById('auth-input').classList.add('hidden');
  document.getElementById('auth-btn').classList.add('hidden');
  const nameEl = document.getElementById('auth-name');
  nameEl.textContent = `✦ ${name}`;
  nameEl.classList.remove('hidden');

  _updateSaveArea();
}

// ── Drawing canvas ─────────────────────────────────────────────────────────────
function _initDrawCanvas() {
  const canvas = document.getElementById('draw-canvas');
  const ctx    = canvas.getContext('2d');
  ctx.fillStyle = '#0f0d1e';
  ctx.fillRect(0, 0, canvas.width, canvas.height);

  let drawing = false, tool = 'pen', color = '#ffffff', size = 6;

  // Brush preview dot
  const preview = document.getElementById('brush-preview');
  function _updatePreview() {
    preview.style.width  = Math.min(size, 24) + 'px';
    preview.style.height = Math.min(size, 24) + 'px';
    preview.style.background = tool === 'eraser' ? 'rgba(255,255,255,.3)' : color;
  }
  _updatePreview();

  function pos(e) {
    const r  = canvas.getBoundingClientRect();
    const sx = canvas.width  / r.width;
    const sy = canvas.height / r.height;
    const s  = e.touches ? e.touches[0] : e;
    return { x: (s.clientX - r.left) * sx, y: (s.clientY - r.top) * sy };
  }

  function down(e) {
    e.preventDefault();
    drawing = true;
    const { x, y } = pos(e);
    ctx.beginPath(); ctx.moveTo(x, y);
  }

  function move(e) {
    e.preventDefault();
    if (!drawing) return;
    const { x, y } = pos(e);
    ctx.lineWidth   = tool === 'eraser' ? size * 3 : size;
    ctx.strokeStyle = tool === 'eraser' ? '#0f0d1e' : color;
    ctx.lineCap = ctx.lineJoin = 'round';
    ctx.globalAlpha = 1;
    ctx.lineTo(x, y); ctx.stroke();
    ctx.beginPath(); ctx.moveTo(x, y);
  }

  function up() { drawing = false; ctx.beginPath(); }

  canvas.addEventListener('mousedown',  down);
  canvas.addEventListener('mousemove',  move);
  canvas.addEventListener('mouseup',    up);
  canvas.addEventListener('mouseleave', up);
  canvas.addEventListener('touchstart', down, { passive: false });
  canvas.addEventListener('touchmove',  move, { passive: false });
  canvas.addEventListener('touchend',   up);

  // Tool buttons
  document.getElementById('t-pen').addEventListener('click', () => {
    tool = 'pen'; _setActiveTool('t-pen'); _updatePreview();
  });
  document.getElementById('t-eraser').addEventListener('click', () => {
    tool = 'eraser'; _setActiveTool('t-eraser'); _updatePreview();
  });

  // Color picker
  document.getElementById('t-color').addEventListener('input', e => {
    color = e.target.value;
    tool = 'pen'; _setActiveTool('t-pen'); _updatePreview();
  });

  // Color swatches
  document.querySelectorAll('.swatch').forEach(s => {
    s.addEventListener('click', () => {
      color = s.dataset.color;
      document.getElementById('t-color').value = color;
      tool = 'pen'; _setActiveTool('t-pen'); _updatePreview();
    });
  });

  // Size slider
  document.getElementById('t-size').addEventListener('input', e => {
    size = +e.target.value; _updatePreview();
  });

  // Clear
  document.getElementById('t-clear').addEventListener('click', () => {
    ctx.fillStyle = '#0f0d1e';
    ctx.fillRect(0, 0, canvas.width, canvas.height);
  });
}

function _setActiveTool(id) {
  document.querySelectorAll('.tool').forEach(t => t.classList.remove('active'));
  document.getElementById(id).classList.add('active');
}

// ── Generation ─────────────────────────────────────────────────────────────────
function _initControls() {
  const slider = document.getElementById('strength');
  const valEl  = document.getElementById('strength-val');
  slider.addEventListener('input', () => { valEl.textContent = slider.value; });
  document.getElementById('generate-btn').addEventListener('click', _generate);
}

async function _generate() {
  const desc = document.getElementById('dream-desc').value.trim();
  if (!desc) { alert('Please describe your dream first.'); return; }

  const canvas   = document.getElementById('draw-canvas');
  const sketch   = canvas.toDataURL('image/png');
  const strength = parseFloat(document.getElementById('strength').value);

  const btn   = document.getElementById('generate-btn');
  const label = document.getElementById('gen-label');
  const spin  = document.getElementById('gen-spin');
  btn.disabled = true;
  label.textContent = '✦ Materializing…';
  spin.classList.remove('hidden');

  try {
    const data = await api('/generate', { sketch_b64: sketch, description: desc, strength });
    if (!data.ok) { alert('Error: ' + data.error); return; }

    state.lastSketch = sketch;
    state.lastDream  = 'data:image/png;base64,' + data.image;

    document.getElementById('res-sketch').src = state.lastSketch;
    document.getElementById('res-dream').src  = state.lastDream;
    document.getElementById('result-area').classList.remove('hidden');
    _updateSaveArea();
  } finally {
    btn.disabled = false;
    label.textContent = '✦ Materialize Dream';
    spin.classList.add('hidden');
  }
}

// ── Save buttons ───────────────────────────────────────────────────────────────
function _initSaveBtns() {
  document.getElementById('btn-publish').addEventListener('click',  () => _save('public'));
  document.getElementById('btn-private').addEventListener('click',  () => _save('private'));
  document.getElementById('btn-download').addEventListener('click', _download);
}

function _updateSaveArea() {
  if (!state.lastDream) return;
  document.getElementById('need-auth').classList.toggle('hidden',  !!state.userId);
  document.getElementById('save-btns').classList.toggle('hidden',  !state.userId);
}

async function _save(visibility) {
  const desc = document.getElementById('dream-desc').value.trim();
  const data = await api('/gallery/save', {
    user_id:     state.userId,
    sketch_b64:  state.lastSketch,
    image_b64:   state.lastDream,
    description: desc,
    visibility,
  });
  if (data.ok) {
    alert(visibility === 'public'
      ? '◈ Dream exhibited in the Museum.'
      : 'Dream saved to your private gallery.');
    if (visibility === 'public') _refreshMuseum();
  } else {
    alert('Could not save: ' + data.error);
  }
}

function _download() {
  if (!state.lastDream) return;
  const a = document.createElement('a');
  a.href = state.lastDream;
  a.download = 'sueno.png';
  a.click();
}

// ── My Gallery ─────────────────────────────────────────────────────────────────
async function _loadUserGallery() {
  const grid = document.getElementById('my-grid');

  if (!state.userId) {
    grid.innerHTML = '<div class="empty-state">Enter your name to see your saved dreams.</div>';
    return;
  }

  document.getElementById('gallery-subtitle').textContent = `${state.userId}'s archive`;
  grid.innerHTML = '<div class="empty-state">Loading…</div>';

  const data = await api('/gallery/user', { user_id: state.userId });
  if (!data.ok || !data.dreams.length) {
    grid.innerHTML = '<div class="empty-state">No dreams saved yet.</div>';
    return;
  }

  grid.innerHTML = '';
  data.dreams.forEach(d => grid.appendChild(_makeCard(d, true)));
}

function _makeCard(dream, isOwner = false) {
  const card = document.createElement('div');
  card.className = 'dream-card';
  card.innerHTML = `
    <div class="card-diptych">
      <img src="${dream.sketch_url}" loading="lazy" alt="boceto" />
      <img src="${dream.image_url}"  loading="lazy" alt="sueño" />
    </div>
    <div class="card-info">
      <div class="card-desc">${dream.description}</div>
      <div class="card-vis">${dream.visibility === 'public' ? '◈ Public' : '◆ Private'}</div>
    </div>
  `;
  card.addEventListener('click', () => openDreamModal(dream, isOwner));
  return card;
}

// ── Dream modal ────────────────────────────────────────────────────────────────
function _initModal() {
  document.querySelector('.modal-close').addEventListener('click', _closeModal);
  document.querySelector('.modal-backdrop').addEventListener('click', _closeModal);
  document.addEventListener('keydown', e => { if (e.key === 'Escape') _closeModal(); });
}

function openDreamModal(dream, isOwner = false) {
  document.getElementById('modal-sketch').src = dream.sketch_url;
  document.getElementById('modal-dream').src  = dream.image_url;
  document.getElementById('modal-desc').textContent = `"${dream.description}"`;
  document.getElementById('modal-meta').textContent =
    `${dream.user_id}  ·  ${dream.timestamp?.slice(0, 10) ?? ''}`;

  const ownerArea = document.getElementById('modal-owner');
  const isMyDream = state.userId && dream.user_id === state.userId;
  ownerArea.classList.toggle('hidden', !isMyDream);

  if (isMyDream) {
    const toggleBtn = document.getElementById('modal-toggle');
    toggleBtn.textContent = dream.visibility === 'public' ? 'Make private' : 'Exhibit publicly';
    toggleBtn.onclick = async () => {
      const r = await api('/gallery/toggle', { dream_id: dream.id, user_id: state.userId });
      if (r.ok) {
        dream.visibility = r.visibility;
        toggleBtn.textContent = dream.visibility === 'public' ? 'Make private' : 'Exhibit publicly';
        _refreshMuseum();
        _loadUserGallery();
      }
    };
    document.getElementById('modal-delete').onclick = async () => {
      if (!confirm('Delete this dream permanently?')) return;
      const r = await api('/gallery/delete', { dream_id: dream.id, user_id: state.userId });
      if (r.ok) { _closeModal(); _loadUserGallery(); _refreshMuseum(); }
    };
  }

  document.getElementById('dream-modal').classList.remove('hidden');
}

function _closeModal() {
  document.getElementById('dream-modal').classList.add('hidden');
}