/**
 * Package API handlers
 */

import type { IApiContext, IApiResponse } from '../router.ts';
import { PermissionService } from '../../services/permission.service.ts';
import { Package, Repository } from '../../models/index.ts';
import type { TRegistryProtocol } from '../../interfaces/auth.interfaces.ts';

export class PackageApi {
  private permissionService: PermissionService;

  constructor(permissionService: PermissionService) {
    this.permissionService = permissionService;
  }

  /**
   * GET /api/v1/packages (search)
   */
  public async search(ctx: IApiContext): Promise<IApiResponse> {
    try {
      const query = ctx.url.searchParams.get('q') || '';
      const protocol = ctx.url.searchParams.get('protocol') as TRegistryProtocol | undefined;
      const organizationId = ctx.url.searchParams.get('organizationId') || undefined;
      const limit = parseInt(ctx.url.searchParams.get('limit') || '50', 10);
      const offset = parseInt(ctx.url.searchParams.get('offset') || '0', 10);

      // For authenticated users, search includes private packages they have access to
      // For anonymous users, only search public packages
      const isPrivate = ctx.actor?.userId ? undefined : false;

      const packages = await Package.search(query, {
        protocol,
        organizationId,
        isPrivate,
        limit,
        offset,
      });

      // Filter out packages user doesn't have access to
      const accessiblePackages = [];
      for (const pkg of packages) {
        if (!pkg.isPrivate) {
          accessiblePackages.push(pkg);
          continue;
        }

        if (ctx.actor?.userId) {
          const canAccess = await this.permissionService.canAccessPackage(
            ctx.actor.userId,
            pkg.organizationId,
            pkg.repositoryId,
            'read'
          );
          if (canAccess) {
            accessiblePackages.push(pkg);
          }
        }
      }

      return {
        status: 200,
        body: {
          packages: accessiblePackages.map((pkg) => ({
            id: pkg.id,
            name: pkg.name,
            description: pkg.description,
            protocol: pkg.protocol,
            organizationId: pkg.organizationId,
            repositoryId: pkg.repositoryId,
            latestVersion: pkg.distTags['latest'],
            isPrivate: pkg.isPrivate,
            downloadCount: pkg.downloadCount,
            updatedAt: pkg.updatedAt,
          })),
          total: accessiblePackages.length,
          limit,
          offset,
        },
      };
    } catch (error) {
      console.error('[PackageApi] Search error:', error);
      return { status: 500, body: { error: 'Failed to search packages' } };
    }
  }

  /**
   * GET /api/v1/packages/:id
   */
  public async get(ctx: IApiContext): Promise<IApiResponse> {
    const { id } = ctx.params;

    try {
      const pkg = await Package.findById(decodeURIComponent(id));
      if (!pkg) {
        return { status: 404, body: { error: 'Package not found' } };
      }

      // Check access
      if (pkg.isPrivate) {
        if (!ctx.actor?.userId) {
          return { status: 401, body: { error: 'Authentication required' } };
        }

        const canAccess = await this.permissionService.canAccessPackage(
          ctx.actor.userId,
          pkg.organizationId,
          pkg.repositoryId,
          'read'
        );

        if (!canAccess) {
          return { status: 403, body: { error: 'Access denied' } };
        }
      }

      return {
        status: 200,
        body: {
          id: pkg.id,
          name: pkg.name,
          description: pkg.description,
          protocol: pkg.protocol,
          organizationId: pkg.organizationId,
          repositoryId: pkg.repositoryId,
          distTags: pkg.distTags,
          versions: Object.keys(pkg.versions),
          isPrivate: pkg.isPrivate,
          downloadCount: pkg.downloadCount,
          starCount: pkg.starCount,
          storageBytes: pkg.storageBytes,
          createdAt: pkg.createdAt,
          updatedAt: pkg.updatedAt,
        },
      };
    } catch (error) {
      console.error('[PackageApi] Get error:', error);
      return { status: 500, body: { error: 'Failed to get package' } };
    }
  }

  /**
   * GET /api/v1/packages/:id/versions
   */
  public async listVersions(ctx: IApiContext): Promise<IApiResponse> {
    const { id } = ctx.params;

    try {
      const pkg = await Package.findById(decodeURIComponent(id));
      if (!pkg) {
        return { status: 404, body: { error: 'Package not found' } };
      }

      // Check access
      if (pkg.isPrivate) {
        if (!ctx.actor?.userId) {
          return { status: 401, body: { error: 'Authentication required' } };
        }

        const canAccess = await this.permissionService.canAccessPackage(
          ctx.actor.userId,
          pkg.organizationId,
          pkg.repositoryId,
          'read'
        );

        if (!canAccess) {
          return { status: 403, body: { error: 'Access denied' } };
        }
      }

      const versions = Object.entries(pkg.versions).map(([version, data]) => ({
        version,
        publishedAt: data.publishedAt,
        size: data.size,
        downloads: data.downloads,
        checksum: data.checksum,
      }));

      return {
        status: 200,
        body: {
          packageId: pkg.id,
          packageName: pkg.name,
          distTags: pkg.distTags,
          versions,
        },
      };
    } catch (error) {
      console.error('[PackageApi] List versions error:', error);
      return { status: 500, body: { error: 'Failed to list versions' } };
    }
  }

  /**
   * DELETE /api/v1/packages/:id
   */
  public async delete(ctx: IApiContext): Promise<IApiResponse> {
    if (!ctx.actor?.userId) {
      return { status: 401, body: { error: 'Authentication required' } };
    }

    const { id } = ctx.params;

    try {
      const pkg = await Package.findById(decodeURIComponent(id));
      if (!pkg) {
        return { status: 404, body: { error: 'Package not found' } };
      }

      // Check delete permission
      const canDelete = await this.permissionService.canAccessPackage(
        ctx.actor.userId,
        pkg.organizationId,
        pkg.repositoryId,
        'delete'
      );

      if (!canDelete) {
        return { status: 403, body: { error: 'Delete permission required' } };
      }

      // Delete the package
      await pkg.delete();

      // Update repository package count
      const repo = await Repository.findById(pkg.repositoryId);
      if (repo) {
        repo.packageCount = Math.max(0, repo.packageCount - 1);
        repo.storageBytes -= pkg.storageBytes;
        await repo.save();
      }

      return {
        status: 200,
        body: { message: 'Package deleted successfully' },
      };
    } catch (error) {
      console.error('[PackageApi] Delete error:', error);
      return { status: 500, body: { error: 'Failed to delete package' } };
    }
  }

  /**
   * DELETE /api/v1/packages/:id/versions/:version
   */
  public async deleteVersion(ctx: IApiContext): Promise<IApiResponse> {
    if (!ctx.actor?.userId) {
      return { status: 401, body: { error: 'Authentication required' } };
    }

    const { id, version } = ctx.params;

    try {
      const pkg = await Package.findById(decodeURIComponent(id));
      if (!pkg) {
        return { status: 404, body: { error: 'Package not found' } };
      }

      const versionData = pkg.versions[version];
      if (!versionData) {
        return { status: 404, body: { error: 'Version not found' } };
      }

      // Check delete permission
      const canDelete = await this.permissionService.canAccessPackage(
        ctx.actor.userId,
        pkg.organizationId,
        pkg.repositoryId,
        'delete'
      );

      if (!canDelete) {
        return { status: 403, body: { error: 'Delete permission required' } };
      }

      // Check if this is the only version
      if (Object.keys(pkg.versions).length === 1) {
        return {
          status: 400,
          body: { error: 'Cannot delete the only version. Delete the entire package instead.' },
        };
      }

      // Remove version
      const sizeReduction = versionData.size;
      delete pkg.versions[version];
      pkg.storageBytes -= sizeReduction;

      // Update dist tags
      for (const [tag, tagVersion] of Object.entries(pkg.distTags)) {
        if (tagVersion === version) {
          delete pkg.distTags[tag];
        }
      }

      // Set new latest if needed
      if (!pkg.distTags['latest'] && Object.keys(pkg.versions).length > 0) {
        const versions = Object.keys(pkg.versions).sort();
        pkg.distTags['latest'] = versions[versions.length - 1];
      }

      await pkg.save();

      // Update repository storage
      const repo = await Repository.findById(pkg.repositoryId);
      if (repo) {
        repo.storageBytes -= sizeReduction;
        await repo.save();
      }

      return {
        status: 200,
        body: { message: 'Version deleted successfully' },
      };
    } catch (error) {
      console.error('[PackageApi] Delete version error:', error);
      return { status: 500, body: { error: 'Failed to delete version' } };
    }
  }
}