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

export class CreateBatchDto {
  @ApiProperty({ 
    description: 'ID of the user creating the batch',
    example: '550e8400-e29b-41d4-a716-446655440000'
  })
  @IsUUID()
  userId: string;

  @ApiPropertyOptional({ 
    description: 'Total number of images in this batch',
    example: 10,
    minimum: 0
  })
  @IsOptional()
  @IsInt()
  @Min(0)
  totalImages?: number;

  @ApiPropertyOptional({ 
    description: 'Additional metadata for the batch processing',
    example: { 
      aiModel: 'gpt-4-vision',
      processingOptions: { includeColors: true, includeTags: true }
    }
  })
  @IsOptional()
  @IsObject()
  metadata?: Record<string, any>;
}

export class UpdateBatchDto {
  @ApiPropertyOptional({ 
    description: 'Batch processing status',
    enum: BatchStatus
  })
  @IsOptional()
  @IsEnum(BatchStatus)
  status?: BatchStatus;

  @ApiPropertyOptional({ 
    description: 'Total number of images in this batch',
    minimum: 0
  })
  @IsOptional()
  @IsInt()
  @Min(0)
  totalImages?: number;

  @ApiPropertyOptional({ 
    description: 'Number of processed images',
    minimum: 0
  })
  @IsOptional()
  @IsInt()
  @Min(0)
  processedImages?: number;

  @ApiPropertyOptional({ 
    description: 'Number of failed images',
    minimum: 0
  })
  @IsOptional()
  @IsInt()
  @Min(0)
  failedImages?: number;

  @ApiPropertyOptional({ 
    description: 'Additional metadata for the batch processing'
  })
  @IsOptional()
  @IsObject()
  metadata?: Record<string, any>;
}

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

  @ApiProperty({ 
    description: 'ID of the user who owns this batch',
    example: '550e8400-e29b-41d4-a716-446655440000'
  })
  @IsUUID()
  userId: string;

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

  @ApiProperty({ 
    description: 'Total number of images in this batch',
    example: 10
  })
  @IsInt()
  @Min(0)
  totalImages: number;

  @ApiProperty({ 
    description: 'Number of processed images',
    example: 8
  })
  @IsInt()
  @Min(0)
  processedImages: number;

  @ApiProperty({ 
    description: 'Number of failed images',
    example: 1
  })
  @IsInt()
  @Min(0)
  failedImages: number;

  @ApiPropertyOptional({ 
    description: 'Additional metadata for the batch processing'
  })
  @IsOptional()
  @IsObject()
  metadata?: Record<string, any>;

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

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

  @ApiPropertyOptional({ 
    description: 'Batch completion timestamp'
  })
  @IsOptional()
  @IsDate()
  completedAt?: Date;
}

export class BatchStatsDto {
  @ApiProperty({ 
    description: 'Processing progress percentage',
    example: 80
  })
  @IsInt()
  @Min(0)
  progressPercentage: number;

  @ApiProperty({ 
    description: 'Number of pending images',
    example: 1
  })
  @IsInt()
  @Min(0)
  pendingImages: number;

  @ApiProperty({ 
    description: 'Average processing time per image in seconds',
    example: 5.2
  })
  @Type(() => Number)
  averageProcessingTime: number;

  @ApiProperty({ 
    description: 'Estimated time remaining in seconds',
    example: 30
  })
  @Type(() => Number)
  estimatedTimeRemaining: number;
}

export class BatchSummaryDto {
  @ApiProperty({ 
    description: 'Batch details'
  })
  batch: BatchResponseDto;

  @ApiProperty({ 
    description: 'Processing statistics'
  })
  stats: BatchStatsDto;

  @ApiProperty({ 
    description: 'Recent images from this batch (limited to 5)'
  })
  recentImages: Array<{
    id: string;
    originalName: string;
    proposedName?: string;
    status: string;
  }>;
}

// Helper function to calculate progress percentage
export function calculateProgressPercentage(processedImages: number, totalImages: number): number {
  if (totalImages === 0) return 0;
  return Math.round((processedImages / totalImages) * 100);
}

// Helper function to determine if batch is complete
export function isBatchComplete(batch: { status: BatchStatus; processedImages: number; failedImages: number; totalImages: number }): boolean {
  return batch.status === BatchStatus.DONE || 
         batch.status === BatchStatus.ERROR ||
         (batch.processedImages + batch.failedImages) >= batch.totalImages;
}