/**
 * @angular-modernizer/plugin-angular - Type Safety Transform Rule
 *
 * Automatically adds missing type annotations to parameters, return types,
 * and class properties, replacing implicit `any` with `unknown`.
 *
 * This transformation follows the "Thin Rule, Thick Orchestrator" pattern:
 * - Rule: Thin wrapper (≤50 lines) delegating to orchestrator
 * - Orchestrator: Contains all business logic for transformation
 *
 * Guarantees:
 * - Idempotent: Safe to run multiple times (guards via getTypeNode() checks)
 * - Atomic: All or nothing per source file
 * - Reversible: Can be undone via git reset
 */
import type {
  TransformRule,
  TransformContext,
  TransformResult,
} from '@angular-modernizer/plugin-system';
import type { PublicApi } from '@angular-modernizer/api';
import { TypeSafetyTransformOrchestrator } from '../orchestrators/type-safety-transform.orchestrator.js';

/**
 * Type Safety Transform Rule - adds missing type annotations.
 *
 * This is a thin wrapper that delegates all business logic to the
 * TypeSafetyTransformOrchestrator following the recommended pattern.
 *
 * @example
 * ```typescript
 * const rule = new TypeSafetyTransformRule();
 * const context = ContextFactory.createTransformContext({ sourceFile, project, api });
 * const result = await rule.transform(context);
 *
 * if (result.modified) {
 *   console.info('Added missing type annotations');
 *   console.info(`Changes: ${result.changeCount}`);
 * }
 * ```
 */
export class TypeSafetyTransformRule implements TransformRule {
  public readonly id = 'angular:type-safety-transform';
  public readonly name = 'Type Safety Transform';
  public readonly description =
    'Adds missing type annotations to parameters, return types, and class properties';
  public readonly category = 'modernization';
  public readonly tags = [
    'angular',
    'typescript',
    'type-safety',
    'modernization',
  ];

  /**
   * Orchestrator instance containing all transformation business logic.
   * @private
   */
  private readonly orchestrator = new TypeSafetyTransformOrchestrator();

  /**
   * Transforms source file by adding missing type annotations.
   *
   * @param context - Transform context with source file and PublicApi
   * @returns Transform result with modification status
   */
  async transform(
    context: TransformContext<PublicApi>,
  ): Promise<TransformResult> {
    const { sourceFile, filePath } = context;

    if (filePath.endsWith('.d.ts')) {
      return {
        ruleId: this.id,
        modified: false,
        message: 'Skipped declaration file',
        filePath,
      };
    }

    // Capture initial state for change detection
    const initialText = sourceFile.getFullText();

    // Delegate ALL business logic to orchestrator
    await this.orchestrator.run(context);

    // Detect if modifications were made
    const modified = sourceFile.getFullText() !== initialText;

    return {
      ruleId: this.id,
      modified,
      message: modified
        ? 'Added missing type annotations'
        : 'No type annotation changes needed',
      filePath,
      changeCount: modified ? 1 : 0,
    };
  }
}