// app.js — bootstrap, input handling, sidebar, attach, paste
import { send, on } from './ws.js';
import { isAuthenticated, logout, getTempId, getClientId } from './auth.js';
import {
  createNewSession, showWelcomeScreen,
  switchSession, currentSessionId, onSessionChange,
} from './sessions.js';
import { submitMessage, renderSession, setActiveSession, getIsStreaming } from './chat.js';
import { openAuthModal, closeModal, openPasteEditor } from './modals.js';
import { openSettings, applyTheme } from './settings.js';
import { showNotification, autoResize, escHtml } from './ui.js';

// ── TOS banner — push content up so input isn't obscured ─────────────────

(function fixTosBanner() {
  const banner = document.getElementById('tos-banner');
  if (!banner) return;
  const applyPadding = () => {
    const isMobile = window.innerWidth <= 768;
    if (isMobile) {
      // On mobile: TOS is fixed at bottom, bottom-input-bar padding is set via CSS
      // Just ensure welcome-view accounts for TOS height
      const h = banner.offsetHeight || 36;
      const welcomeView = document.getElementById('welcome-view');
      if (welcomeView) welcomeView.style.paddingBottom = `${h + 8}px`;
    } else {
      const h = banner.offsetHeight || 42;
      document.getElementById('bottom-input-bar')?.style.setProperty('padding-bottom', `${h + 8}px`);
      const welcomeView = document.getElementById('welcome-view');
      if (welcomeView) welcomeView.style.paddingBottom = `${h + 16}px`;
    }
  };
  requestAnimationFrame(() => { applyPadding(); });
  window.addEventListener('resize', applyPadding);
})();

// ── Sidebar ───────────────────────────────────────────────────────────────

const sidebar   = document.getElementById('sidebar');
const toggleBtn = document.getElementById('toggle-sidebar-btn');

function expandSidebar()  { sidebar?.classList.remove('collapsed'); sidebar?.classList.add('expanded'); }
function collapseSidebar(){ sidebar?.classList.remove('expanded'); sidebar?.classList.add('collapsed'); }
function toggleSidebar()  { sidebar?.classList.contains('expanded') ? collapseSidebar() : expandSidebar(); }

toggleBtn?.addEventListener('click', toggleSidebar);

// ── Mobile top bar + sidebar logic ───────────────────────────────────────

(function setupMobile() {
  // Create backdrop
  const backdrop = document.createElement('div');
  backdrop.id = 'sidebar-backdrop';
  backdrop.className = 'sidebar-backdrop';
  document.body.appendChild(backdrop);

  function openSidebar()  { sidebar?.classList.remove('collapsed'); sidebar?.classList.add('expanded'); backdrop.classList.add('visible'); }
  function closeSidebar() { sidebar?.classList.remove('expanded'); sidebar?.classList.add('collapsed'); backdrop.classList.remove('visible'); }

  backdrop.addEventListener('click', closeSidebar);

  // Wire mobile top bar buttons
  document.getElementById('mobile-sidebar-btn')?.addEventListener('click', () => {
    sidebar?.classList.contains('expanded') ? closeSidebar() : openSidebar();
  });
  document.getElementById('mobile-newchat-btn')?.addEventListener('click', () => {
    showWelcomeScreen();
    const ci = document.getElementById('center-input');
    if (ci) { ci.value = ''; autoResize(ci, 6); }
    const box = document.getElementById('chat-messages');
    if (box) box.innerHTML = '';
  });

  // Auto-close drawer when a session is switched on mobile
  onSessionChange((event) => {
    if ((event === 'switched' || event === 'created') && window.innerWidth <= 768) {
      closeSidebar();
    }
  });

  // ── Hide/show top bar on scroll ─────────────────────────────────────────
  let lastScrollY = 0;
  let ticking = false;
  const topBar = document.getElementById('mobile-top-bar');

  function handleChatScroll(e) {
    if (window.innerWidth > 768) return;
    const el = e.target;
    const currentY = el.scrollTop;
    if (!ticking) {
      requestAnimationFrame(() => {
        if (currentY > lastScrollY && currentY > 60) {
          // Scrolling down — hide bar
          topBar?.classList.add('hidden-bar');
        } else {
          // Scrolling up — show bar
          topBar?.classList.remove('hidden-bar');
        }
        lastScrollY = currentY <= 0 ? 0 : currentY;
        ticking = false;
      });
      ticking = true;
    }
  }

  // Attach to chat-view scroll
  document.getElementById('chat-view')?.addEventListener('scroll', handleChatScroll, { passive: true });

  // Always show top bar when on welcome screen
  onSessionChange((event, data) => {
    if (event === 'switched' && !data) {
      topBar?.classList.remove('hidden-bar');
      lastScrollY = 0;
    }
  });
})();

// ── New chat — just show the welcome screen; don't create a session yet ───

document.getElementById('new-chat-btn')?.addEventListener('click', () => {
  showWelcomeScreen();
  if (window.innerWidth < 768) { /* handled by setupMobile onSessionChange */ }
  const ci = document.getElementById('center-input');
  if (ci) { ci.value = ''; autoResize(ci, 6); }
  const box = document.getElementById('chat-messages');
  if (box) box.innerHTML = '';
});

// ── Session switching ─────────────────────────────────────────────────────

onSessionChange((event, data) => {
  if (event === 'switched') {
    setActiveSession(data);
    if (!data) {
      // Clear chat when going to welcome
      const box = document.getElementById('chat-messages');
      if (box) box.innerHTML = '';
      document.getElementById('welcome-view')?.classList.remove('hidden');
      document.getElementById('chat-view')?.classList.add('hidden');
      document.getElementById('bottom-input-bar')?.classList.add('hidden');
    }
  }
  if (event === 'data') {
    if (data.id === currentSessionId) renderSession(data);
  }
  if (event === 'created') {
    setActiveSession(data.id);
    switchSession(data.id);
  }
});

// ── Center input (welcome view) ───────────────────────────────────────────

const centerInput   = document.getElementById('center-input');
const centerSendBtn = document.getElementById('center-send-btn');

centerInput?.addEventListener('input', () => autoResize(centerInput, 6));
centerInput?.addEventListener('keydown', e => {
  if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); triggerCenterSend(); }
});
centerSendBtn?.addEventListener('click', triggerCenterSend);

// Center tool buttons
document.querySelectorAll('#center-tool-search, #center-tool-image, #center-tool-video, #center-tool-audio')
  .forEach(btn => btn.addEventListener('click', () => btn.classList.toggle('active')));

function triggerCenterSend() {
  const text = centerInput?.value.trim();
  const attachments = pendingAttachments.splice(0);
  if (!text && attachments.length === 0) return;
  if (centerInput) { centerInput.value = ''; autoResize(centerInput, 6); }
  clearFilePreviewRow();

  const pendingText = text, pendingAttach = attachments;
  const unsub = onSessionChange((ev, s) => {
    if (ev !== 'switched' || !s) return;
    unsub();
    doSend(pendingText, pendingAttach);
  });
  createNewSession();
}

// ── Bottom input (active chat) ────────────────────────────────────────────

const bottomInput   = document.getElementById('bottom-input');
const bottomSendBtn = document.getElementById('bottom-send-btn');

bottomInput?.addEventListener('input', () => autoResize(bottomInput, 6));
bottomInput?.addEventListener('keydown', e => {
  if (e.key === 'Enter' && !e.shiftKey) { e.preventDefault(); triggerBottomSend(); }
});
bottomSendBtn?.addEventListener('click', () => {
  if (getIsStreaming()) { send({ type: 'chat:stop' }); return; }
  triggerBottomSend();
});

function triggerBottomSend() {
  const text = bottomInput?.value.trim();
  const attachments = pendingAttachments.splice(0);
  if (!text && attachments.length === 0) return;
  if (bottomInput) { bottomInput.value = ''; autoResize(bottomInput, 6); }
  clearFilePreviewRow();
  doSend(text || '', attachments);
}

document.querySelectorAll('.tool-btn-sm').forEach(btn =>
  btn.addEventListener('click', () => btn.classList.toggle('active')));

// ── Core send ─────────────────────────────────────────────────────────────

function doSend(text, attachments = []) {
  submitMessage(text, attachments);
}

// ── Attachments ───────────────────────────────────────────────────────────

let pendingAttachments = [];
const LARGE_PASTE_THRESHOLD = 10000;

function openAttachMenu(e, triggerEl) {
  e.preventDefault(); e.stopPropagation();
  const menu = document.getElementById('attach-context-menu');
  if (!menu) return;
  menu.innerHTML = '';

  for (const item of [
    { label: '📄 Upload file',  onClick: () => document.getElementById('file-input')?.click() },
    { label: '🖼️ Upload image', onClick: () => document.getElementById('image-input')?.click() },
  ]) {
    const el = document.createElement('div');
    el.className = 'context-item'; el.textContent = item.label;
    el.addEventListener('click', () => { menu.classList.add('hidden'); item.onClick(); });
    menu.appendChild(el);
  }

  menu.classList.remove('hidden');
  const rect = triggerEl.getBoundingClientRect();
  const mh = menu.getBoundingClientRect().height || 80;
  menu.style.left = `${Math.max(8, rect.left)}px`;
  menu.style.top  = `${rect.top - mh - 8}px`;

  setTimeout(() => document.addEventListener('click', () => menu.classList.add('hidden'), { once: true }), 0);
}

document.getElementById('center-attach-btn')?.addEventListener('click', e =>
  openAttachMenu(e, document.getElementById('center-attach-btn')));
document.getElementById('bottom-attach-btn')?.addEventListener('click', e =>
  openAttachMenu(e, document.getElementById('bottom-attach-btn')));

document.getElementById('file-input')?.addEventListener('change', async function() {
  for (const file of this.files) {
    const text = await file.text();
    pendingAttachments.push({ type: 'text', name: file.name, content: text });
  }
  this.value = '';
  renderFilePreviewRow();
});

document.getElementById('image-input')?.addEventListener('change', async function() {
  for (const file of this.files) await addImageFile(file);
  this.value = '';
});

async function addImageFile(file) {
  const dataUrl = await new Promise((res, rej) => {
    const reader = new FileReader();
    reader.onload  = () => res(reader.result);
    reader.onerror = rej;
    reader.readAsDataURL(file);
  });
  const comma = dataUrl.indexOf(',');
  const mimeType = dataUrl.slice(5, dataUrl.indexOf(';'));
  const base64   = dataUrl.slice(comma + 1);
  pendingAttachments.push({ type: 'image', name: file.name, base64, mimeType });
  renderFilePreviewRow();
}

function buildAttachmentItem(a, i) {
  const wrap = document.createElement('div');
  wrap.className = 'attach-preview-item';

  if (a.type === 'image') {
    const img = document.createElement('img');
    img.src = `data:${a.mimeType};base64,${a.base64}`;
    img.alt = a.name;
    wrap.appendChild(img);
  } else {
    const chip = document.createElement('div');
    chip.className = 'pasted-chip';
    const icon = document.createElement('span'); icon.textContent = '📄';
    const name = document.createElement('span'); name.textContent = a.name;
    chip.appendChild(icon); chip.appendChild(name);
    chip.addEventListener('click', () => openPasteEditor(a.content, nc => { pendingAttachments[i].content = nc; }));
    wrap.appendChild(chip);
  }

  const rm = document.createElement('button');
  rm.className = 'attach-preview-remove';
  rm.textContent = '×';
  rm.addEventListener('click', e => { e.stopPropagation(); pendingAttachments.splice(i, 1); renderFilePreviewRow(); });
  wrap.appendChild(rm);
  return wrap;
}

function renderFilePreviewRow() {
  const centerRow = document.getElementById('center-file-preview-row');
  const bottomRow = document.getElementById('file-preview-row');

  [centerRow, bottomRow].forEach(row => {
    if (!row) return;
    row.innerHTML = '';
    if (pendingAttachments.length === 0) { row.style.display = 'none'; return; }
    row.style.display = 'flex';
    pendingAttachments.forEach((a, i) => row.appendChild(buildAttachmentItem(a, i)));
  });
}

function clearFilePreviewRow() {
  pendingAttachments = [];
  ['center-file-preview-row', 'file-preview-row'].forEach(id => {
    const row = document.getElementById(id);
    if (row) { row.innerHTML = ''; row.style.display = 'none'; }
  });
}

// ── Paste & drag-drop ─────────────────────────────────────────────────────

function handlePaste(e) {
  const items = Array.from(e.clipboardData?.items || []);

  const imgItem = items.find(i => i.kind === 'file' && i.type.startsWith('image/'));
  if (imgItem) { e.preventDefault(); addImageFile(imgItem.getAsFile()); return; }

  const textItem = items.find(i => i.kind === 'string' && i.type === 'text/plain');
  if (textItem) {
    textItem.getAsString(text => {
      if (text.length > LARGE_PASTE_THRESHOLD) {
        e.preventDefault();
        pendingAttachments.push({ type: 'text', name: `pasted-${Date.now()}.txt`, content: text });
        renderFilePreviewRow();
      }
    });
  }
}

[centerInput, bottomInput].forEach(input => {
  input?.addEventListener('paste', handlePaste);
  input?.addEventListener('dragover', e => e.preventDefault());
  input?.addEventListener('drop', async e => {
    e.preventDefault();
    for (const file of e.dataTransfer.files)
      if (file.type.startsWith('image/')) await addImageFile(file);
  });
});

// ── Auth/settings buttons ─────────────────────────────────────────────────

document.getElementById('signin-btn')?.addEventListener('click', () => openAuthModal('signin'));
document.getElementById('signin-icon-btn')?.addEventListener('click', () => openAuthModal('signin'));
document.getElementById('settings-btn')?.addEventListener('click', () => openSettings('chat'));
document.getElementById('settings-btn-guest')?.addEventListener('click', () => openSettings('chat'));

document.getElementById('user-profile-btn')?.addEventListener('click', e => {
  const btn = e.currentTarget;
  const rect = btn.getBoundingClientRect();
  const menu = document.getElementById('user-context-menu');
  if (!menu) return;

  const menuItems = [
    { label: '⚙️  Settings',       onClick: () => openSettings('chat') },
    { label: '👤  Account',         onClick: () => openSettings('account') },
    { label: '💳  Billing Portal',  onClick: () => window.open('https://sharktide-lightning.hf.space/portal', '_blank') },
    { sep: true },
    { label: '🗑️  Clear All Chats', danger: true,
      onClick: () => { if (confirm('Delete all chats? This cannot be undone.')) send({ type: 'sessions:deleteAll' }); }},
    { sep: true },
    { label: '🚪  Sign Out',        danger: true, onClick: () => logout() },
  ];

  menu.innerHTML = '';
  for (const item of menuItems) {
    if (item.sep) {
      const s = document.createElement('div'); s.style.cssText = 'height:1px;background:var(--border);margin:3px 0;';
      menu.appendChild(s); continue;
    }
    const el = document.createElement('div');
    el.className = 'context-item' + (item.danger ? ' danger' : '');
    el.textContent = item.label;
    el.addEventListener('click', () => { menu.classList.add('hidden'); item.onClick(); });
    menu.appendChild(el);
  }

  menu.classList.remove('hidden');
  const mw = 200;
  let left = rect.left, top = rect.top;
  const mh = menu.scrollHeight || 200;
  top = rect.top - mh - 8;
  if (left + mw > window.innerWidth - 8) left = window.innerWidth - mw - 8;
  menu.style.left = `${Math.max(8, left)}px`;
  menu.style.top  = `${Math.max(8, top)}px`;

  setTimeout(() => document.addEventListener('click', () => menu.classList.add('hidden'), { once: true }), 0);
});

// ── Share import from URL ?share=token ────────────────────────────────────

function checkShareParam() {
  const params = new URLSearchParams(location.search);
  const token  = params.get('share');
  if (!token) return;

  const banner    = document.getElementById('share-import-banner');
  const bannerText= document.getElementById('share-banner-text');
  const importBtn = document.getElementById('share-import-btn');
  const dismissBtn= document.getElementById('share-dismiss-btn');

  fetch(`/api/share/${encodeURIComponent(token)}`)
    .then(r => r.ok ? r.json() : null)
    .then(data => {
      if (!data) return;
      if (bannerText) bannerText.textContent = `Import shared chat: "${data.name}"?`;
      banner?.classList.remove('hidden');
    })
    .catch(() => {});

  importBtn?.addEventListener('click', () => {
    if (!isAuthenticated()) { openAuthModal('signin'); return; }
    send({ type: 'sessions:import', token });
    banner?.classList.add('hidden');
    history.replaceState({}, '', '/');
  });
  dismissBtn?.addEventListener('click', () => {
    banner?.classList.add('hidden');
    history.replaceState({}, '', '/');
  });
}

// ── Connection notifications & reconnect handling ─────────────────────────

let wasDisconnected = false;
on('ws:disconnected', () => {
  wasDisconnected = true;
  showNotification({ type: 'warning', message: 'Connection lost — reconnecting…', duration: 3000 });
});
on('ws:connected', () => {
  if (wasDisconnected) {
    showNotification({ type: 'success', message: 'Reconnected', duration: 2000 });
  }
  wasDisconnected = false;
});

// ── Init ──────────────────────────────────────────────────────────────────

document.addEventListener('DOMContentLoaded', () => {
  checkShareParam();
  applyTheme('dark'); // default until auth resolves
});