import { Controller, Post, Logger, BadRequestException } from '@nestjs/common';
import { ApiOperation, ApiResponse, ApiTags } from '@nestjs/swagger';
import { RedisService } from '@box/db/redis/redis.service';
import { MongoPrismaService } from '@box/db/prisma/mongo-prisma.service';
import { VideoCategoryCacheBuilder } from '@box/core/cache/video/category/video-category-cache.builder';
import { tsCacheKeys } from '@box/common/cache/ts-cache-key.provider';

/**
 * VideoCacheAdminController
 *
 * PRODUCTION-SAFE ADMIN ENDPOINT
 * ═══════════════════════════════════════════════════════════════════════════
 *
 * This controller provides AUTHORIZED ADMIN-ONLY endpoints for video cache management.
 * Unlike dev endpoints (/dev/cache/...), this is designed for production use.
 *
 * Routes:
 * - POST /api/v1/mgnt/admin/cache/video/rebuild
 *
 * Access Control:
 * - Protected by RbacGuard + JwtAuthGuard
 * - Requires proper API permissions (configured via role-based menu API permissions)
 * - Suitable only for super-admin or trusted operators
 *
 * Response:
 * - Minimal, no internal Redis details or raw key information
 * - Success indicator + deletion counts + rebuild timestamp
 * - Detailed logging via Logger for audit trail
 *
 * ═══════════════════════════════════════════════════════════════════════════
 * IMPORTANT: This is production-safe and will NOT be disabled in production.
 * Access is controlled via role-based permissions (RbacGuard).
 * ═══════════════════════════════════════════════════════════════════════════
 */
@ApiTags('缓存管理 - Admin (生产)', 'Cache Management - Admin (Production)')
@Controller('api/v1/mgnt/admin/cache/video')
export class VideoCacheAdminController {
  private readonly logger = new Logger(VideoCacheAdminController.name);

  constructor(
    private readonly redisService: RedisService,
    private readonly mongoPrisma: MongoPrismaService,
    private readonly videoCategoryCacheBuilder: VideoCategoryCacheBuilder,
  ) {}

  /**
   * POST /api/v1/mgnt/admin/cache/video/rebuild
   *
   * Rebuild video cache: clear old keys and rebuild all categories/tags.
   *
   * This endpoint:
   * 1. Scans for and deletes video cache keys matching patterns
   * 2. Calls VideoCategoryCacheBuilder.buildAll() to repopulate cache
   * 3. Returns deletion counts and rebuild timestamp
   *
   * Patterns deleted:
   * - box:app:video:category:list:* (category video lists)
   * - box:app:video:tag:list:*     (tag-filtered video lists)
   * - box:app:tag:list:*           (tag metadata lists)
   *
   * @returns {Promise<VideoCacheRebuildResponse>} Success indicator, deletion stats, rebuild timestamp
   * @throws {BadRequestException} If Redis scan or build operation fails
   */
  @Post('rebuild')
  @ApiOperation({
    summary: 'Rebuild video cache (admin only)',
    description:
      'Clear video cache keys and rebuild from database. Requires admin role permissions.',
  })
  @ApiResponse({
    status: 200,
    description: 'Cache rebuild completed successfully',
    schema: {
      type: 'object',
      example: {
        success: true,
        deleted: {
          categoryLists: 15,
          tagVideoLists: 42,
          tagMetadataLists: 8,
          total: 65,
        },
        rebuiltAt: '2025-12-06T10:30:45.123Z',
      },
    },
  })
  @ApiResponse({
    status: 400,
    description: 'Cache operation failed (e.g., Redis error, build error)',
  })
  @ApiResponse({
    status: 403,
    description: 'Forbidden - User lacks admin permissions',
  })
  async rebuildVideoCache(): Promise<VideoCacheRebuildResponse> {
    const startTime = Date.now();
    this.logger.log('[AdminCache] Starting video cache rebuild...');

    try {
      // Step 1: Delete video cache keys by pattern
      const deletionStats = await this.deleteVideoCache();

      // Step 2: Rebuild video cache from database
      this.logger.log('[AdminCache] Triggering cache builder rebuild...');
      try {
        await this.videoCategoryCacheBuilder.buildAll();
        this.logger.log('[AdminCache] Cache rebuild completed successfully');
      } catch (buildError) {
        this.logger.error(
          `[AdminCache] Cache rebuild failed: ${buildError instanceof Error ? buildError.message : 'Unknown error'}`,
          buildError instanceof Error ? buildError.stack : undefined,
        );
        throw new BadRequestException('Cache rebuild operation failed');
      }

      // Step 3: Return success response with stats
      const duration = Date.now() - startTime;
      this.logger.log(
        `[AdminCache] Video cache rebuild completed successfully (${duration}ms)`,
      );

      return {
        success: true,
        deleted: deletionStats,
        rebuiltAt: new Date().toISOString(),
      };
    } catch (error) {
      const duration = Date.now() - startTime;
      this.logger.error(
        `[AdminCache] Video cache rebuild failed after ${duration}ms: ${error instanceof Error ? error.message : 'Unknown error'}`,
        error instanceof Error ? error.stack : undefined,
      );

      if (error instanceof BadRequestException) {
        throw error;
      }

      throw new BadRequestException('Video cache rebuild operation failed');
    }
  }

  /**
   * Delete video cache keys matching specific patterns
   *
   * Patterns deleted:
   * - box:app:video:category:list:*
   * - box:app:video:tag:list:*
   * - box:app:tag:list:*
   */
  private async deleteVideoCache(): Promise<VideoCacheDeletionStats> {
    this.logger.log('[AdminCache] Deleting video cache keys...');

    const stats: VideoCacheDeletionStats = {
      categoryLists: 0,
      tagVideoLists: 0,
      tagMetadataLists: 0,
      total: 0,
    };

    try {
      // Delete category video lists: box:app:video:category:list:*
      const categoryListKeys = await this.redisService.keys(
        tsCacheKeys.video.categoryList('*'),
      );
      if (categoryListKeys.length > 0) {
        const deleted = await this.redisService.del(...categoryListKeys);
        stats.categoryLists = deleted;
        stats.total += deleted;
        this.logger.log(`[AdminCache] Deleted ${deleted} category video lists`);
      }

      // Delete tag video lists: box:app:video:tag:list:*:*
      const tagListKeys = await this.redisService.keys(
        tsCacheKeys.video.tagList('*', '*'),
      );
      if (tagListKeys.length > 0) {
        const deleted = await this.redisService.del(...tagListKeys);
        stats.tagVideoLists = deleted;
        stats.total += deleted;
        this.logger.log(`[AdminCache] Deleted ${deleted} tag video lists`);
      }

      // Delete tag metadata lists: box:app:tag:list:*
      const tagMetadataKeys = await this.redisService.keys(
        tsCacheKeys.tag.metadataByCategory('*'),
      );
      if (tagMetadataKeys.length > 0) {
        const deleted = await this.redisService.del(...tagMetadataKeys);
        stats.tagMetadataLists = deleted;
        stats.total += deleted;
        this.logger.log(`[AdminCache] Deleted ${deleted} tag metadata lists`);
      }

      this.logger.log(`[AdminCache] Total keys deleted: ${stats.total}`);
      return stats;
    } catch (error) {
      this.logger.error(
        `[AdminCache] Failed to delete cache keys: ${error instanceof Error ? error.message : 'Unknown error'}`,
        error instanceof Error ? error.stack : undefined,
      );
      throw new BadRequestException('Failed to delete video cache keys');
    }
  }
}

/**
 * Response shape for video cache rebuild endpoint
 */
export interface VideoCacheDeletionStats {
  categoryLists: number;
  tagVideoLists: number;
  tagMetadataLists: number;
  total: number;
}

export interface VideoCacheRebuildResponse {
  success: boolean;
  deleted: VideoCacheDeletionStats;
  rebuiltAt: string;
}