import { Injectable, inject } from '@angular/core';
import { DocumentService } from './document.service';
import { SelectionService } from './selection.service';
import { PaletteService } from './palette.service';
import { SHORTCUTS, matchesShortcut } from '../core/constants/keyboard';
import { BlockType } from '../core/models/block.model';

/**
 * Keyboard shortcuts handler service
 */
@Injectable({
  providedIn: 'root'
})
export class ShortcutsService {
  private readonly documentService = inject(DocumentService);
  private readonly selectionService = inject(SelectionService);
  private readonly paletteService = inject(PaletteService);

  /**
   * Handle keyboard event
   */
  handleKeyDown(event: KeyboardEvent): boolean {
    // Find matching shortcut
    for (const shortcut of SHORTCUTS) {
      if (matchesShortcut(event, shortcut)) {
        this.executeAction(shortcut.action, event);
        event.preventDefault();
        return true;
      }
    }
    return false;
  }

  /**
   * Execute shortcut action
   */
  private executeAction(action: string, event: KeyboardEvent): void {
    const activeBlockId = this.selectionService.getActive();

    switch (action) {
      // Palette
      case 'open-palette':
        this.paletteService.open(activeBlockId);
        break;

      // Headings
      case 'heading-1':
        this.insertOrConvertBlock('heading', { level: 1, text: '' });
        break;
      case 'heading-2':
        this.insertOrConvertBlock('heading', { level: 2, text: '' });
        break;
      case 'heading-3':
        this.insertOrConvertBlock('heading', { level: 3, text: '' });
        break;

      // Lists
      case 'bullet-list':
        this.insertOrConvertBlock('list', { kind: 'bullet' });
        break;
      case 'numbered-list':
        this.insertOrConvertBlock('list', { kind: 'numbered' });
        break;
      case 'checkbox-list':
        this.insertOrConvertBlock('list', { kind: 'check' });
        break;

      // Blocks
      case 'toggle':
        this.insertOrConvertBlock('toggle', { title: 'Toggle', content: [], collapsed: true });
        break;
      case 'code':
        this.insertOrConvertBlock('code', { code: '', lang: '' });
        break;
      case 'quote':
        this.insertOrConvertBlock('quote', { text: '' });
        break;
      case 'hint':
        this.insertOrConvertBlock('hint', { text: '', variant: 'info' });
        break;
      case 'button':
        this.insertOrConvertBlock('button', { label: 'Button', url: '', variant: 'primary' });
        break;

      // Block operations
      case 'delete-block':
        if (activeBlockId) {
          this.documentService.deleteBlock(activeBlockId);
        }
        break;

      case 'move-block-up':
        if (activeBlockId) {
          const blocks = this.documentService.blocks();
          const index = blocks.findIndex(b => b.id === activeBlockId);
          if (index > 0) {
            this.documentService.moveBlock(activeBlockId, index - 1);
          }
        }
        break;

      case 'move-block-down':
        if (activeBlockId) {
          const blocks = this.documentService.blocks();
          const index = blocks.findIndex(b => b.id === activeBlockId);
          if (index >= 0 && index < blocks.length - 1) {
            this.documentService.moveBlock(activeBlockId, index + 1);
          }
        }
        break;

      case 'duplicate-block':
        if (activeBlockId) {
          this.documentService.duplicateBlock(activeBlockId);
        }
        break;

      // Overlay
      case 'close-overlay':
        if (this.paletteService.isOpen()) {
          this.paletteService.close();
        }
        break;

      // Save
      case 'save':
        // Save is automatic via effect
        console.log('Document auto-saved');
        break;

      // Text formatting (handled by block components)
      case 'bold':
      case 'italic':
      case 'underline':
      case 'link':
        // These are handled by individual block components
        break;

      default:
        console.log('Unhandled action:', action);
    }
  }

  /**
   * Insert or convert block based on context
   */
  private insertOrConvertBlock(type: BlockType, preset?: any): void {
    const activeBlockId = this.selectionService.getActive();

    if (activeBlockId) {
      // Convert existing block
      this.documentService.convertBlock(activeBlockId, type, preset);
    } else {
      // Insert new block at end
      const block = this.documentService.createBlock(type, this.documentService.getDefaultProps(type));
      if (preset) {
        block.props = { ...block.props, ...preset };
      }
      // If it's a list created via shortcut, seed the first item's text for immediate visibility
      if (type === 'list') {
        const k = (block.props?.kind || '').toLowerCase();
        const label = k === 'check' ? 'checkbox-list' : k === 'numbered' ? 'numbered-list' : 'bullet-list';
        if (Array.isArray(block.props?.items) && block.props.items.length > 0) {
          block.props.items = [{ ...block.props.items[0], text: label }];
        }
      }
      this.documentService.appendBlock(block);
      this.selectionService.setActive(block.id);
    }
  }
}