import { ApiPropertyOptional } from '@nestjs/swagger';
import { Transform, Type } from 'class-transformer';
import { IsBoolean, IsDate, IsInt, IsNumber, IsOptional, IsString, Min } from 'class-validator';

export class FlatQueryCategoryDto {
  @ApiPropertyOptional({ description: 'Number of records to take', default: 10 })
  @IsOptional()
  @IsInt()
  @Min(1)
  @Type(() => Number)
  take = 10;

  @ApiPropertyOptional({ description: 'Number of records to skip', default: 0 })
  @IsOptional()
  @IsInt()
  @Min(0)
  @Type(() => Number)
  skip = 0;

  @ApiPropertyOptional({ description: `Filter Category where id equals` })
  @IsOptional()
  @IsInt()
  @Type(() => Number)
  id?: number;

  @ApiPropertyOptional({ description: `Filter Category where name equals` })
  @IsOptional()
  @IsString()
  name?: string;

  @ApiPropertyOptional({ description: `Filter Category where description equals` })
  @IsOptional()
  @IsString()
  description?: string;

  @ApiPropertyOptional({ description: `Filter Category where parentId equals` })
  @IsOptional()
  @IsInt()
  @Type(() => Number)
  parentId?: number;

  @ApiPropertyOptional({ description: `Filter Category where createdAt greater than or equal` })
  @IsOptional()
  @IsDate()
  @Type(() => Date)
  createdAt_gte?: Date;

  @ApiPropertyOptional({ description: `Filter Category where createdAt less than or equal` })
  @IsOptional()
  @IsDate()
  @Type(() => Date)
  createdAt_lte?: Date;

  @ApiPropertyOptional({ description: `Filter Category where updatedAt greater than or equal` })
  @IsOptional()
  @IsDate()
  @Type(() => Date)
  updatedAt_gte?: Date;

  @ApiPropertyOptional({ description: `Filter Category where updatedAt less than or equal` })
  @IsOptional()
  @IsDate()
  @Type(() => Date)
  updatedAt_lte?: Date;


  /**
   * Transform flat query parameters to Prisma query structure
   */
  toPrismaQuery() {
    const result: any = {
      take: this.take,
      skip: this.skip,
      where: {}
    };

    // Process all filter parameters
    for (const [key, value] of Object.entries(this)) {
      if (key === 'take' || key === 'skip' || value === undefined) {
        continue;
      }

      const parts = key.split('_');
      if (parts.length === 2) {
        // Handle field_operator pattern (e.g. firstName_contains)
        const [fieldName, operator] = parts;
        
        // Initialize the field object if it doesn't exist
        if (!result.where[fieldName]) {
          result.where[fieldName] = {};
        }
        
        // Set the operator
        result.where[fieldName][operator] = value;
      } else if (parts.length === 1) {
        // Handle direct field name (equals operator)
        const fieldName = key;
        
        // Initialize the field object if it doesn't exist
        if (!result.where[fieldName]) {
          result.where[fieldName] = {};
        }
        
        // Use equals operator
        result.where[fieldName]['equals'] = value;
      }
    }

    return result;
  }
}