import { 
  IsString, 
  IsEnum, 
  IsInt, 
  IsOptional, 
  IsUUID, 
  IsObject,
  MinLength,
  MaxLength,
  Min,
  IsDate 
} from 'class-validator';
import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
import { ImageStatus } from '@prisma/client';
import { Type } from 'class-transformer';

export interface VisionTagsInterface {
  objects?: string[];
  colors?: string[];
  scene?: string;
  description?: string;
  confidence?: number;
  aiModel?: string;
  processingTime?: number;
}

export interface ImageDimensionsInterface {
  width: number;
  height: number;
  aspectRatio?: string;
}

export class CreateImageDto {
  @ApiProperty({ 
    description: 'ID of the batch this image belongs to',
    example: '550e8400-e29b-41d4-a716-446655440000'
  })
  @IsUUID()
  batchId: string;

  @ApiProperty({ 
    description: 'Original filename of the image',
    example: 'IMG_20240101_123456.jpg'
  })
  @IsString()
  @MinLength(1)
  @MaxLength(255)
  originalName: string;

  @ApiPropertyOptional({ 
    description: 'File size in bytes',
    example: 2048576
  })
  @IsOptional()
  @IsInt()
  @Min(0)
  fileSize?: number;

  @ApiPropertyOptional({ 
    description: 'MIME type of the image',
    example: 'image/jpeg'
  })
  @IsOptional()
  @IsString()
  mimeType?: string;

  @ApiPropertyOptional({ 
    description: 'Image dimensions',
    example: { width: 1920, height: 1080, aspectRatio: '16:9' }
  })
  @IsOptional()
  @IsObject()
  dimensions?: ImageDimensionsInterface;

  @ApiPropertyOptional({ 
    description: 'S3 object key for storage',
    example: 'uploads/user123/batch456/original/image.jpg'
  })
  @IsOptional()
  @IsString()
  s3Key?: string;
}

export class UpdateImageDto {
  @ApiPropertyOptional({ 
    description: 'AI-generated proposed filename',
    example: 'modern-kitchen-with-stainless-steel-appliances.jpg'
  })
  @IsOptional()
  @IsString()
  @MaxLength(255)
  proposedName?: string;

  @ApiPropertyOptional({ 
    description: 'User-approved final filename',
    example: 'kitchen-renovation-final.jpg'
  })
  @IsOptional()
  @IsString()
  @MaxLength(255)
  finalName?: string;

  @ApiPropertyOptional({ 
    description: 'AI vision analysis results',
    example: {
      objects: ['kitchen', 'refrigerator', 'countertop'],
      colors: ['white', 'stainless steel', 'black'],
      scene: 'modern kitchen interior',
      description: 'A modern kitchen with stainless steel appliances',
      confidence: 0.95,
      aiModel: 'gpt-4-vision',
      processingTime: 2.5
    }
  })
  @IsOptional()
  @IsObject()
  visionTags?: VisionTagsInterface;

  @ApiPropertyOptional({ 
    description: 'Image processing status',
    enum: ImageStatus
  })
  @IsOptional()
  @IsEnum(ImageStatus)
  status?: ImageStatus;

  @ApiPropertyOptional({ 
    description: 'Error message if processing failed',
    example: 'Image format not supported'
  })
  @IsOptional()
  @IsString()
  @MaxLength(500)
  processingError?: string;
}

export class ImageResponseDto {
  @ApiProperty({ 
    description: 'Unique image identifier',
    example: '550e8400-e29b-41d4-a716-446655440000'
  })
  @IsUUID()
  id: string;

  @ApiProperty({ 
    description: 'ID of the batch this image belongs to',
    example: '550e8400-e29b-41d4-a716-446655440000'
  })
  @IsUUID()
  batchId: string;

  @ApiProperty({ 
    description: 'Original filename of the image',
    example: 'IMG_20240101_123456.jpg'
  })
  @IsString()
  originalName: string;

  @ApiPropertyOptional({ 
    description: 'AI-generated proposed filename',
    example: 'modern-kitchen-with-stainless-steel-appliances.jpg'
  })
  @IsOptional()
  @IsString()
  proposedName?: string;

  @ApiPropertyOptional({ 
    description: 'User-approved final filename',
    example: 'kitchen-renovation-final.jpg'
  })
  @IsOptional()
  @IsString()
  finalName?: string;

  @ApiPropertyOptional({ 
    description: 'AI vision analysis results'
  })
  @IsOptional()
  @IsObject()
  visionTags?: VisionTagsInterface;

  @ApiProperty({ 
    description: 'Current image processing status',
    enum: ImageStatus
  })
  @IsEnum(ImageStatus)
  status: ImageStatus;

  @ApiPropertyOptional({ 
    description: 'File size in bytes',
    example: 2048576
  })
  @IsOptional()
  @IsInt()
  fileSize?: number;

  @ApiPropertyOptional({ 
    description: 'Image dimensions'
  })
  @IsOptional()
  @IsObject()
  dimensions?: ImageDimensionsInterface;

  @ApiPropertyOptional({ 
    description: 'MIME type of the image',
    example: 'image/jpeg'
  })
  @IsOptional()
  @IsString()
  mimeType?: string;

  @ApiPropertyOptional({ 
    description: 'S3 object key for storage',
    example: 'uploads/user123/batch456/original/image.jpg'
  })
  @IsOptional()
  @IsString()
  s3Key?: string;

  @ApiPropertyOptional({ 
    description: 'Error message if processing failed'
  })
  @IsOptional()
  @IsString()
  processingError?: string;

  @ApiProperty({ 
    description: 'Image creation timestamp'
  })
  @IsDate()
  createdAt: Date;

  @ApiProperty({ 
    description: 'Image last update timestamp'
  })
  @IsDate()
  updatedAt: Date;

  @ApiPropertyOptional({ 
    description: 'Image processing completion timestamp'
  })
  @IsOptional()
  @IsDate()
  processedAt?: Date;
}

export class ImageProcessingResultDto {
  @ApiProperty({ 
    description: 'Image details'
  })
  image: ImageResponseDto;

  @ApiProperty({ 
    description: 'Processing success status'
  })
  success: boolean;

  @ApiPropertyOptional({ 
    description: 'Processing time in seconds'
  })
  @IsOptional()
  @Type(() => Number)
  processingTime?: number;

  @ApiPropertyOptional({ 
    description: 'Error details if processing failed'
  })
  @IsOptional()
  @IsString()
  error?: string;
}

export class BulkImageUpdateDto {
  @ApiProperty({ 
    description: 'Array of image IDs to update',
    example: ['550e8400-e29b-41d4-a716-446655440000', '660f9511-f39c-52e5-b827-557766551111']
  })
  @IsUUID(undefined, { each: true })
  imageIds: string[];

  @ApiPropertyOptional({ 
    description: 'Status to set for all images',
    enum: ImageStatus
  })
  @IsOptional()
  @IsEnum(ImageStatus)
  status?: ImageStatus;

  @ApiPropertyOptional({ 
    description: 'Apply proposed names as final names for all images'
  })
  @IsOptional()
  applyProposedNames?: boolean;
}

// Helper function to generate SEO-friendly filename
export function generateSeoFriendlyFilename(
  visionTags: VisionTagsInterface, 
  originalName: string
): string {
  if (!visionTags.objects && !visionTags.description) {
    return originalName;
  }

  let filename = '';
  
  // Use description if available, otherwise use objects
  if (visionTags.description) {
    filename = visionTags.description
      .toLowerCase()
      .replace(/[^a-z0-9\s-]/g, '') // Remove special characters
      .replace(/\s+/g, '-') // Replace spaces with hyphens
      .replace(/-+/g, '-') // Replace multiple hyphens with single
      .substring(0, 100); // Limit length
  } else if (visionTags.objects && visionTags.objects.length > 0) {
    filename = visionTags.objects
      .slice(0, 3) // Take first 3 objects
      .join('-')
      .toLowerCase()
      .replace(/[^a-z0-9-]/g, '')
      .substring(0, 100);
  }

  // Get file extension from original name
  const extension = originalName.split('.').pop()?.toLowerCase() || 'jpg';
  
  return filename ? `${filename}.${extension}` : originalName;
}

// Helper function to validate image file type
export function isValidImageType(mimeType: string): boolean {
  const validTypes = [
    'image/jpeg',
    'image/jpg', 
    'image/png',
    'image/webp',
    'image/gif',
    'image/bmp',
    'image/tiff'
  ];
  return validTypes.includes(mimeType.toLowerCase());
}

// Helper function to calculate aspect ratio
export function calculateAspectRatio(width: number, height: number): string {
  const gcd = (a: number, b: number): number => b === 0 ? a : gcd(b, a % b);
  const divisor = gcd(width, height);
  return `${width / divisor}:${height / divisor}`;
}