import { useEffect } from 'react';

export interface KeyboardShortcut {
  key: string;
  ctrl?: boolean;
  shift?: boolean;
  alt?: boolean;
  meta?: boolean;
  handler: (event: KeyboardEvent) => void;
  description?: string;
}

/**
 * Hook to register keyboard shortcuts
 *
 * @example
 * ```tsx
 * useKeyboard([
 *   {
 *     key: 'c',
 *     meta: true, // Cmd on Mac, Ctrl on Windows
 *     handler: () => copyToClipboard(),
 *     description: 'Copy color',
 *   },
 *   {
 *     key: 'k',
 *     meta: true,
 *     handler: () => openCommandPalette(),
 *     description: 'Open command palette',
 *   },
 * ]);
 * ```
 */
export function useKeyboard(shortcuts: KeyboardShortcut[]) {
  useEffect(() => {
    const handleKeyDown = (event: KeyboardEvent) => {
      for (const shortcut of shortcuts) {
        const keyMatches = event.key.toLowerCase() === shortcut.key.toLowerCase();

        // Check if required modifiers match (only check if explicitly required)
        const ctrlMatches = shortcut.ctrl === true ? event.ctrlKey : true;
        const shiftMatches = shortcut.shift === true ? event.shiftKey : true;
        const altMatches = shortcut.alt === true ? event.altKey : true;

        // Handle meta/cmd key with cross-platform support
        let metaMatches = true;
        if (shortcut.meta === true) {
          // On Mac: require Cmd key
          // On Windows/Linux: accept Ctrl key as Cmd equivalent
          const isMac = navigator.platform.includes('Mac');
          metaMatches = isMac ? event.metaKey : event.ctrlKey;
        }

        // Ensure unwanted modifiers are not pressed (unless explicitly required)
        const noExtraCtrl = shortcut.ctrl === true || shortcut.meta === true || !event.ctrlKey;
        const noExtraShift = shortcut.shift === true || !event.shiftKey;
        const noExtraAlt = shortcut.alt === true || !event.altKey;
        const noExtraMeta = shortcut.meta === true || !event.metaKey;

        if (
          keyMatches &&
          ctrlMatches &&
          shiftMatches &&
          altMatches &&
          metaMatches &&
          noExtraCtrl &&
          noExtraShift &&
          noExtraAlt &&
          noExtraMeta
        ) {
          event.preventDefault();
          shortcut.handler(event);
          break;
        }
      }
    };

    window.addEventListener('keydown', handleKeyDown);

    return () => {
      window.removeEventListener('keydown', handleKeyDown);
    };
  }, [shortcuts]);
}

/**
 * Hook to register a single keyboard shortcut (convenience wrapper)
 */
export function useKeyboardShortcut(
  key: string,
  handler: (event: KeyboardEvent) => void,
  modifiers?: {
    ctrl?: boolean;
    shift?: boolean;
    alt?: boolean;
    meta?: boolean;
  }
) {
  useKeyboard([
    {
      key,
      ...modifiers,
      handler,
    },
  ]);
}