import { useEffect, useRef } from 'react';
import { useEditorStore } from '../store/editorStore';
import { loadBindings } from '../lib/keybindings';
import type { KeyBinding } from '../types/project';

export function useKeyboardShortcuts() {
  const addCutRange = useEditorStore((s) => s.addCutRange);
  const markInTime = useEditorStore((s) => s.markInTime);
  const markOutTime = useEditorStore((s) => s.markOutTime);
  const setMarkInTime = useEditorStore((s) => s.setMarkInTime);
  const setMarkOutTime = useEditorStore((s) => s.setMarkOutTime);
  const clearMarkRange = useEditorStore((s) => s.clearMarkRange);
  const selectedWordIndices = useEditorStore((s) => s.selectedWordIndices);
  const words = useEditorStore((s) => s.words);
  const playbackRateRef = useRef(1);

  // Read bindings fresh from localStorage on every call to avoid stale closures
  const getBindings = (): KeyBinding[] => {
    try { return loadBindings(); } catch { return []; }
  };

  useEffect(() => {
    const getVideo = (): HTMLVideoElement | null => document.querySelector('video');

    const handler = (e: KeyboardEvent) => {
      const target = e.target as HTMLElement;
      if (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA' || target.tagName === 'SELECT') return;

      const video = getVideo();

      // Build a key string from the event for matching
      const parts: string[] = [];
      if (e.ctrlKey || e.metaKey) parts.push('Ctrl');
      if (e.shiftKey && !['Shift'].includes(e.key)) parts.push('Shift');
      if (e.altKey) parts.push('Alt');
      const keyStr = e.key === ' ' ? 'Space' : e.key.length === 1 ? e.key.toUpperCase() : e.key;
      parts.push(keyStr);
      const combo = parts.join('+');

      // Look up binding — fresh read every keystroke so Settings changes take effect immediately
      const currentBindings = getBindings();
      const binding = currentBindings.find((b) => b.keys === combo);
      if (!binding) return;  // Unbound key — ignore

      e.preventDefault();

      switch (binding.id) {
        case 'undo':
          useEditorStore.temporal.getState().undo();
          return;
        case 'redo':
          useEditorStore.temporal.getState().redo();
          return;
        case 'cut': {
          if (selectedWordIndices.length > 0) {
            const sorted = [...selectedWordIndices].sort((a, b) => a - b);
            addCutRange(words[sorted[0]].start, words[sorted[sorted.length - 1]].end);
            return;
          }
          if (markInTime !== null && markOutTime !== null) {
            const start = Math.min(markInTime, markOutTime);
            const end = Math.max(markInTime, markOutTime);
            if (end - start >= 0.01) addCutRange(start, end);
            clearMarkRange();
          }
          return;
        }
        case 'play-pause':
          if (video) { if (video.paused) video.play(); else video.pause(); }
          return;
        case 'slow-down': {
          if (video) {
            playbackRateRef.current = Math.max(-2, playbackRateRef.current - 0.5);
            if (playbackRateRef.current < 0) video.currentTime = Math.max(0, video.currentTime - 2);
            else { video.playbackRate = playbackRateRef.current; if (video.paused) video.play(); }
          }
          return;
        }
        case 'pause':
          if (video) { video.pause(); playbackRateRef.current = 1; }
          return;
        case 'speed-up': {
          if (video) {
            playbackRateRef.current = Math.min(4, playbackRateRef.current + 0.5);
            video.playbackRate = Math.max(0.25, playbackRateRef.current);
            if (video.paused) video.play();
          }
          return;
        }
        case 'rewind':
          if (video) video.currentTime = Math.max(0, video.currentTime - 5);
          return;
        case 'forward':
          if (video) video.currentTime = Math.min(video.duration, video.currentTime + 5);
          return;
        case 'mark-in':
          if (video) setMarkInTime(video.currentTime);
          return;
        case 'mark-out':
          if (video) setMarkOutTime(video.currentTime);
          return;
        case 'save': {
          const saveBtn = document.querySelector('[title="Save"]') as HTMLButtonElement | null;
          if (saveBtn) saveBtn.click();
          else saveProject();
          return;
        }
        case 'export': {
          const exportBtn = document.querySelector('[title="Export"]') as HTMLButtonElement;
          if (exportBtn) exportBtn.click();
          return;
        }
        case 'search': {
          const findBtn = document.querySelector('[title="Find (Ctrl+F)"]') as HTMLButtonElement;
          if (findBtn) findBtn.click();
          return;
        }
        case 'help':
          toggleCheatsheet(currentBindings);
          return;
        default:
          break;
      }
    };

    window.addEventListener('keydown', handler);
    return () => window.removeEventListener('keydown', handler);
  }, [addCutRange, markInTime, markOutTime, setMarkInTime, setMarkOutTime, clearMarkRange, selectedWordIndices, words]);
}

async function saveProject() {
  const state = useEditorStore.getState();
  if (!state.videoPath || state.words.length === 0) return;

  try {
    const projectData = state.saveProject();
    let outputPath = state.projectFilePath;

    if (!outputPath) {
      outputPath = await window.electronAPI?.saveFile({
        defaultPath: state.videoPath.replace(/\.[^.]+$/, '.aive'),
        filters: [{ name: 'TalkEdit Project', extensions: ['aive'] }],
      });
    }

    if (!outputPath) return;

    const resolvedPath = outputPath.endsWith('.aive') ? outputPath : `${outputPath}.aive`;

    if (window.electronAPI?.writeFile) {
      await window.electronAPI.writeFile(resolvedPath, JSON.stringify(projectData, null, 2));
      useEditorStore.getState().setProjectFilePath(resolvedPath);
    } else {
      const blob = new Blob([JSON.stringify(projectData, null, 2)], { type: 'application/json' });
      const url = URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.href = url;
      a.download = resolvedPath.split(/[\\/]/).pop() || 'project.aive';
      a.click();
      URL.revokeObjectURL(url);
      useEditorStore.getState().setProjectFilePath(resolvedPath);
    }
  } catch (err) {
    console.error('Failed to save project:', err);
  }
}

function toggleCheatsheet(bindings: KeyBinding[]) {
  const existing = document.getElementById('keyboard-cheatsheet');
  if (existing) {
    existing.remove();
    return;
  }

  const overlay = document.createElement('div');
  overlay.id = 'keyboard-cheatsheet';
  overlay.style.cssText =
    'position:fixed;inset:0;z-index:9999;display:flex;align-items:center;justify-content:center;background:rgba(0,0,0,0.7);';
  overlay.onclick = () => {
    overlay.remove();
  };

  const rows = bindings
    .map(
      (b) =>
        `<tr><td style="padding:6px 16px 6px 0;font-family:monospace;color:#818cf8;font-weight:600;white-space:nowrap">${b.keys}</td><td style="padding:6px 0;color:#e2e8f0">${b.label}</td><td style="padding:6px 0 6px 12px;font-size:10px;color:#94a3b8">${b.category}</td></tr>`,
    )
    .join('');

  overlay.innerHTML = `<div style="background:#1a1d27;border:1px solid #2a2d3a;border-radius:12px;padding:24px 32px;max-width:450px;position:relative;" onclick="event.stopPropagation()">
    <h3 style="margin:0 0 16px;font-size:14px;font-weight:600;color:#e2e8f0">Keyboard Shortcuts</h3>
    <table style="font-size:13px">${rows}</table>
    <p style="margin:16px 0 0;font-size:11px;color:#94a3b8;text-align:center">Customize in Settings &bull; Press ? to close</p>
    <button id="cheatsheet-close" style="position:absolute;top:12px;right:16px;background:none;border:none;color:#94a3b8;font-size:18px;cursor:pointer;line-height:1;padding:4px;">&times;</button>
  </div>`;

  document.body.appendChild(overlay);

  const closeBtn = overlay.querySelector('#cheatsheet-close') as HTMLButtonElement;
  if (closeBtn) closeBtn.onclick = () => overlay.remove();

  const escHandler = (e: KeyboardEvent) => {
    if (e.key === 'Escape') {
      overlay.remove();
      document.removeEventListener('keydown', escHandler);
    }
  };
  document.addEventListener('keydown', escHandler);
}