import { useEffect } from 'react';
import { useHistoryStore } from '@/store/history-store';
import { useToolStore, useLayerStore, useTextStore } from '@/store';
import { duplicateLayerWithHistory, deleteLayerWithHistory } from '@/lib/layer-operations';
import type { ToolType } from '@/types';

/**
 * Keyboard shortcuts configuration
 */
interface KeyboardShortcut {
  key: string;
  ctrl?: boolean;
  shift?: boolean;
  alt?: boolean;
  meta?: boolean;
  handler: () => void;
  description: string;
}

/**
 * Tool shortcuts mapping
 */
const TOOL_SHORTCUTS: Record<string, ToolType> = {
  '1': 'pencil',
  '2': 'brush',
  '3': 'eraser',
  '4': 'fill',
  '5': 'eyedropper',
  '6': 'text',
  '7': 'select',
};

/**
 * Hook to manage keyboard shortcuts
 */
export function useKeyboardShortcuts() {
  const { undo, redo, canUndo, canRedo } = useHistoryStore();
  const { setActiveTool } = useToolStore();
  const { layers, activeLayerId, setActiveLayer } = useLayerStore();
  const { isOnCanvasEditorActive } = useTextStore();

  useEffect(() => {
    const handleKeyDown = (e: KeyboardEvent) => {
      // Check if we're in an input field or text editor is active
      const target = e.target as HTMLElement;
      if (
        isOnCanvasEditorActive ||
        target.tagName === 'INPUT' ||
        target.tagName === 'TEXTAREA' ||
        target.isContentEditable
      ) {
        return;
      }

      // Tool selection shortcuts: 1-7
      if (TOOL_SHORTCUTS[e.key]) {
        e.preventDefault();
        setActiveTool(TOOL_SHORTCUTS[e.key]);
        return;
      }

      // Layer navigation: Arrow Up/Down
      if (e.key === 'ArrowUp' || e.key === 'ArrowDown') {
        e.preventDefault();

        // Sort layers by order (highest first, same as UI)
        const sortedLayers = [...layers].sort((a, b) => b.order - a.order);
        const currentIndex = sortedLayers.findIndex((l) => l.id === activeLayerId);

        if (currentIndex === -1) return;

        if (e.key === 'ArrowUp' && currentIndex > 0) {
          setActiveLayer(sortedLayers[currentIndex - 1].id);
        } else if (e.key === 'ArrowDown' && currentIndex < sortedLayers.length - 1) {
          setActiveLayer(sortedLayers[currentIndex + 1].id);
        }
        return;
      }

      // Delete layer: Delete or Backspace (without modifier keys)
      if ((e.key === 'Delete' || e.key === 'Backspace') && !e.ctrlKey && !e.metaKey && !e.shiftKey) {
        e.preventDefault();
        if (activeLayerId && layers.length > 1) {
          if (confirm('Delete this layer?')) {
            deleteLayerWithHistory(activeLayerId);
          }
        }
        return;
      }

      // Duplicate layer: Ctrl+D
      if ((e.ctrlKey || e.metaKey) && e.key === 'd' && !e.shiftKey) {
        e.preventDefault();
        if (activeLayerId) {
          duplicateLayerWithHistory(activeLayerId);
        }
        return;
      }

      // Undo: Ctrl+Z (but not Ctrl+Shift+Z)
      if ((e.ctrlKey || e.metaKey) && e.key === 'z' && !e.shiftKey) {
        e.preventDefault();
        if (canUndo()) {
          undo();
        }
        return;
      }

      // Redo: Ctrl+Shift+Z or Ctrl+Y
      if (
        ((e.ctrlKey || e.metaKey) && e.key === 'z' && e.shiftKey) ||
        ((e.ctrlKey || e.metaKey) && e.key === 'y')
      ) {
        e.preventDefault();
        if (canRedo()) {
          redo();
        }
        return;
      }
    };

    window.addEventListener('keydown', handleKeyDown);

    return () => {
      window.removeEventListener('keydown', handleKeyDown);
    };
  }, [
    undo,
    redo,
    canUndo,
    canRedo,
    setActiveTool,
    layers,
    activeLayerId,
    setActiveLayer,
    isOnCanvasEditorActive,
  ]);
}

/**
 * Get keyboard shortcut display string
 */
export function getShortcutDisplay(shortcut: {
  key: string;
  ctrl?: boolean;
  shift?: boolean;
  alt?: boolean;
  meta?: boolean;
}): string {
  const parts: string[] = [];

  const isMac = typeof navigator !== 'undefined' && /Mac|iPhone|iPad|iPod/.test(navigator.platform);

  if (shortcut.ctrl || shortcut.meta) {
    parts.push(isMac ? '⌘' : 'Ctrl');
  }
  if (shortcut.shift) {
    parts.push(isMac ? '⇧' : 'Shift');
  }
  if (shortcut.alt) {
    parts.push(isMac ? '⌥' : 'Alt');
  }

  parts.push(shortcut.key.toUpperCase());

  return parts.join(isMac ? '' : '+');
}