/**
 * Presigned URL API Endpoint
 * Agent 3: File Upload & Storage System
 *
 * POST /api/upload/presigned - Get a presigned URL for direct upload
 */

import type { NextApiRequest, NextApiResponse } from 'next';
import { getUploadService } from '../../../lib/storage';
import type { FileCategory, PresignedUrlResponse } from '../../../lib/storage/types';

interface RequestBody {
  filename: string;
  contentType: string;
  category: FileCategory;
  expiresIn?: number;
}

interface PresignedResponse {
  success: boolean;
  data?: PresignedUrlResponse;
  error?: string;
}

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse<PresignedResponse>
) {
  if (req.method !== 'POST') {
    return res.status(405).json({ success: false, error: 'Method not allowed' });
  }

  try {
    const { filename, contentType, category, expiresIn } = req.body as RequestBody;

    // Validate required fields
    if (!filename || !contentType || !category) {
      return res.status(400).json({
        success: false,
        error: 'Missing required fields: filename, contentType, category',
      });
    }

    // Validate category
    const validCategories: FileCategory[] = ['plant-photo', 'certificate', 'document', 'report', 'avatar'];
    if (!validCategories.includes(category)) {
      return res.status(400).json({
        success: false,
        error: `Invalid category. Must be one of: ${validCategories.join(', ')}`,
      });
    }

    // Validate content type
    const allowedContentTypes = [
      'image/jpeg',
      'image/png',
      'image/gif',
      'image/webp',
      'image/heic',
      'image/heif',
      'application/pdf',
      'application/msword',
      'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
    ];

    if (!allowedContentTypes.includes(contentType)) {
      return res.status(400).json({
        success: false,
        error: `Invalid content type. Must be one of: ${allowedContentTypes.join(', ')}`,
      });
    }

    const uploadService = getUploadService();
    const presignedUrl = await uploadService.getPresignedUploadUrl({
      filename,
      contentType,
      category,
      expiresIn: expiresIn || 3600, // Default 1 hour
    });

    return res.status(200).json({
      success: true,
      data: presignedUrl,
    });
  } catch (error) {
    console.error('Presigned URL error:', error);
    return res.status(500).json({
      success: false,
      error: error instanceof Error ? error.message : 'Internal server error',
    });
  }
}