'use client';

import { useEffect, useRef } from 'react';
import { useDockviewStore } from '@/lib/state/dockview-store';
import { useAppStoreApi } from '@/components/state-provider';
import { createUserShell } from '@/lib/api/domains/user-shell-api';
import type { DockviewApi } from 'dockview-react';

function handleTabNavigation(e: KeyboardEvent, api: DockviewApi) {
  const activePanel = api.activePanel;
  if (!activePanel) return;

  const panels = activePanel.group.panels;
  if (panels.length <= 1) return;

  const currentIndex = panels.findIndex((p) => p.id === activePanel.id);
  if (currentIndex === -1) return;

  e.preventDefault();
  e.stopPropagation();

  const direction = e.code === 'BracketLeft' ? -1 : 1;
  const nextIndex = (currentIndex + direction + panels.length) % panels.length;
  panels[nextIndex].api.setActive();
}

function handleTerminalToggle(
  e: KeyboardEvent,
  api: DockviewApi,
  previousPanelIdRef: React.MutableRefObject<string | null>,
  getSessionId: () => string | null,
) {
  e.preventDefault();
  e.stopPropagation();

  const activePanel = api.activePanel;
  const isTerminalFocused = activePanel?.id.startsWith('terminal-') ?? false;

  if (isTerminalFocused) {
    const prevId = previousPanelIdRef.current;
    const target = prevId ? api.getPanel(prevId) : api.getPanel('chat');
    if (target) target.api.setActive();
    previousPanelIdRef.current = null;
    return;
  }

  if (activePanel) {
    previousPanelIdRef.current = activePanel.id;
  }

  const terminalPanel = api.panels.find((p) => p.id.startsWith('terminal-'));
  if (terminalPanel) {
    terminalPanel.api.setActive();
    return;
  }

  const sessionId = getSessionId();
  if (!sessionId) return;

  createUserShell(sessionId)
    .then((result) => {
      useDockviewStore.getState().addTerminalPanel(result.terminalId);
    })
    .catch((err) => { console.warn('Failed to create terminal shell:', err); });
}

/**
 * Global editor keybinds for dockview:
 * - Cmd/Ctrl+Shift+[ / ] — navigate prev/next tab in active group
 * - Ctrl+` — toggle terminal focus
 */
export function useEditorKeybinds() {
  const previousPanelIdRef = useRef<string | null>(null);
  const appStore = useAppStoreApi();

  useEffect(() => {
    const handler = (e: KeyboardEvent) => {
      const api = useDockviewStore.getState().api;
      if (!api) return;

      const isTabNav =
        (e.metaKey || e.ctrlKey) &&
        e.shiftKey &&
        (e.code === 'BracketLeft' || e.code === 'BracketRight');

      if (isTabNav) {
        handleTabNavigation(e, api);
        return;
      }

      const isTerminalToggle =
        e.ctrlKey && !e.metaKey && !e.shiftKey && e.code === 'Backquote';

      if (isTerminalToggle) {
        handleTerminalToggle(
          e,
          api,
          previousPanelIdRef,
          () => appStore.getState().tasks.activeSessionId,
        );
      }
    };

    window.addEventListener('keydown', handler);
    return () => window.removeEventListener('keydown', handler);
  }, [appStore]);
}