import { useEffect, useCallback } from 'react';

export interface KeyboardShortcut {
  key: string;
  ctrl?: boolean;
  shift?: boolean;
  alt?: boolean;
  description: string;
  action: () => void;
  enabled?: boolean;
}

export interface UseKeyboardShortcutsOptions {
  shortcuts: KeyboardShortcut[];
  ignoreWhenInputFocused?: boolean;
}

/**
 * Hook for managing keyboard shortcuts
 * Automatically handles event listeners and cleanup
 */
export function useKeyboardShortcuts({
  shortcuts,
  ignoreWhenInputFocused = true,
}: UseKeyboardShortcutsOptions) {
  const handleKeyDown = useCallback(
    (event: KeyboardEvent) => {
      // Ignore if typing in input/textarea/select
      if (ignoreWhenInputFocused) {
        const target = event.target as HTMLElement;
        const tagName = target.tagName.toLowerCase();
        const isEditable = target.isContentEditable;

        if (
          tagName === 'input' ||
          tagName === 'textarea' ||
          tagName === 'select' ||
          isEditable
        ) {
          // Allow ESC to blur inputs
          if (event.key === 'Escape') {
            target.blur();
          }
          return;
        }
      }

      // Find matching shortcut
      for (const shortcut of shortcuts) {
        if (shortcut.enabled === false) continue;

        const keyMatches = event.key.toLowerCase() === shortcut.key.toLowerCase();
        const ctrlMatches = shortcut.ctrl ? event.ctrlKey || event.metaKey : !event.ctrlKey && !event.metaKey;
        const shiftMatches = shortcut.shift ? event.shiftKey : !event.shiftKey;
        const altMatches = shortcut.alt ? event.altKey : !event.altKey;

        if (keyMatches && ctrlMatches && shiftMatches && altMatches) {
          event.preventDefault();
          shortcut.action();
          break;
        }
      }
    },
    [shortcuts, ignoreWhenInputFocused]
  );

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

/**
 * Common keyboard shortcuts for reference
 */
export const COMMON_SHORTCUTS = {
  SEARCH: { key: '/', description: 'Focus search' },
  REFRESH: { key: 'r', description: 'Refresh data' },
  SELECT_ALL: { key: 'a', description: 'Select all' },
  ESCAPE: { key: 'Escape', description: 'Clear selection / Close modal' },
  HELP: { key: '?', shift: true, description: 'Show keyboard shortcuts' },
  NEXT: { key: 'j', description: 'Next item' },
  PREVIOUS: { key: 'k', description: 'Previous item' },
  SELECT: { key: ' ', description: 'Toggle selection' },
  START: { key: 's', description: 'Start selected' },
  STOP: { key: 'x', description: 'Stop selected' },
  RESTART: { key: 't', description: 'Restart selected' },
} as const;