// ── Chat Page ──

registerPage('chat', {
  async init(params) {
    const sessionId = params.id;
    if (!sessionId) return navigateTo('dashboard');

    currentSessionId = sessionId;

    const session = await apiGetSession(sessionId);
    if (!session) return navigateTo('dashboard');

    // Kein Agent = kein Chat
    if (!session.agentId) {
      navigateTo('session', { id: sessionId });
      return;
    }

    const titleEl = document.getElementById('sessionTitle');
    if (titleEl) {
      titleEl.textContent = session.name || 'Unbenannt';
    }

    // Custom Command Buttons
    const cmdBar = document.getElementById('customCmdBar');
    if (cmdBar) {
      cmdBar.innerHTML = '';
      let cmds = [];
      try { cmds = JSON.parse(session.customCommands || '[]') || []; } catch(e) {}
      cmds.forEach(cmd => {
        if (!cmd.name || !cmd.command) return;
        const btn = document.createElement('button');
        btn.className = 'custom-cmd-btn';
        btn.textContent = cmd.name;
        btn.title = cmd.command;
        btn.addEventListener('click', async () => {
          btn.disabled = true;
          btn.classList.add('running');
          try {
            await apiExecCommand(sessionId, cmd.command);
          } catch(e) {
            console.error('Exec failed:', e);
          }
          setTimeout(() => {
            btn.disabled = false;
            btn.classList.remove('running');
          }, 1000);
        });
        cmdBar.appendChild(btn);
      });
    }

    // Zurück zur Session-Edit-Seite
    const backBtn = document.getElementById('chatBackBtn');
    if (backBtn) {
      backBtn.addEventListener('click', () => navigateTo('session', { id: sessionId }));
    }

    // Send
    const sendBtn = document.getElementById('send');
    if (sendBtn) sendBtn.addEventListener('click', sendMessage);

    const inputEl = document.getElementById('input');
    if (inputEl) {
      inputEl.addEventListener('keydown', (e) => {
        if (e.key === 'Enter' && !e.shiftKey && !e.ctrlKey && !e.altKey && !e.metaKey) {
          e.preventDefault();
          sendMessage();
        }
      });
      inputEl.addEventListener('input', function () {
        this.style.height = 'auto';
        this.style.height = Math.min(this.scrollHeight, 150) + 'px';
      });
      inputEl.dispatchEvent(new Event('input'))
    }

    // Workspace Explorer
    const explorerBtn = document.getElementById('explorerBtn');
    if (explorerBtn) {
      explorerBtn.addEventListener('click', () => {
        openFileExplorer({
          sessionId,
          onSelect(ref) {
            addPendingRef(ref);
            document.getElementById('input')?.focus();
          }
        });
      });
    }

    // File Upload
    const fileBtn = document.getElementById('fileBtn');
    const fileInput = document.getElementById('fileInput');
    if (fileBtn && fileInput) {
      fileBtn.addEventListener('click', () => fileInput.click());
      fileInput.addEventListener('change', (e) => {
        if (e.target.files.length > 0) handleMultipleFiles(e.target.files);
      });
    }

    // Drag & Drop
    const chatContainer = document.querySelector('.chat-page');
    if (chatContainer) {
      chatContainer.addEventListener('dragover', (e) => { e.preventDefault(); e.stopPropagation(); });
      chatContainer.addEventListener('drop', (e) => {
        e.preventDefault();
        e.stopPropagation();
        if (e.dataTransfer.files.length > 0) handleMultipleFiles(e.dataTransfer.files);
      });
    }

    // Paste
    if (inputEl) {
      inputEl.addEventListener('paste', (e) => {
        const items = e.clipboardData?.items;
        if (!items) return;
        for (const item of items) {
          if (item.kind === 'file') {
            e.preventDefault();
            handleFileSelect(item.getAsFile());
            return;
          }
        }
      });
    }

    // Header-Menü (3-Dot)
    const chatMenuBtn = document.getElementById('chatMenuBtn');
    const chatMenuDropdown = document.getElementById('chatMenuDropdown');
    if (chatMenuBtn && chatMenuDropdown) {
      chatMenuBtn.addEventListener('click', (e) => {
        e.stopPropagation();
        chatMenuDropdown.hidden = !chatMenuDropdown.hidden;
      });
      document.addEventListener('click', this._closeMenu = () => {
        chatMenuDropdown.hidden = true;
      });
    }

    // Archivieren
    const archiveBtn = document.getElementById('archiveBtn');
    if (archiveBtn) archiveBtn.addEventListener('click', () => {
      if (chatMenuDropdown) chatMenuDropdown.hidden = true;
      clearChat();
    });

    // State zurücksetzen und History laden
    messages.length = 0;
    lastKnownMessageId = 0;
    loadedArchiveCount = 0;
    isStreaming = false;

    await loadHistory();
  },

  destroy() {
    if (this._closeMenu) {
      document.removeEventListener('click', this._closeMenu);
      this._closeMenu = null;
    }
    stopHistoryPolling();
    messages.length = 0;
    lastKnownMessageId = 0;
    loadedArchiveCount = 0;
    isStreaming = false;
    clearPendingFiles();
    clearPendingRefs();
  }
});