import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
import { Transform } from 'class-transformer';
import {
  IsDateString,
  IsIn,
  IsNumber,
  IsOptional,
  IsString,
  MaxLength,
  Min,
} from 'class-validator';

import {
  TARGET_DIMENSIONS,
  TARGET_METRICS,
  TARGET_PERIOD_TYPES,
  TargetDimension,
  TargetMetric,
  TargetPeriodType,
} from '../entities/operations-target.entity';

const toNumber = ({ value }: { value: unknown }) =>
  value === '' || value == null ? value : Number(value);

export class CreateOperationsTargetDto {
  @ApiProperty({ enum: TARGET_PERIOD_TYPES })
  @IsIn(TARGET_PERIOD_TYPES as unknown as string[])
  periodType!: TargetPeriodType;

  @ApiProperty({
    example: '2026-08-01',
    description: 'Any date inside the bucket — normalised to the bucket start on write.',
  })
  @IsDateString()
  periodStart!: string;

  @ApiProperty({ enum: TARGET_METRICS })
  @IsIn(TARGET_METRICS as unknown as string[])
  metric!: TargetMetric;

  @ApiProperty({ enum: TARGET_DIMENSIONS })
  @IsIn(TARGET_DIMENSIONS as unknown as string[])
  dimension!: TargetDimension;

  @ApiProperty({
    example: 'CONTAINER_IMPORT_MULTIMODAL',
    description: 'Category key, container-class key or yard code — not a display label.',
  })
  @IsString()
  @MaxLength(60)
  dimensionKey!: string;

  @ApiProperty({ example: 1200 })
  @Transform(toNumber)
  @IsNumber()
  @Min(0)
  plannedValue!: number;

  @ApiPropertyOptional({
    description:
      'Station targets only: which cargo category this station plan covers. Ignored for the ' +
      'other dimensions, whose key already carries the category.',
    example: 'CONTAINER_IMPORT_MULTIMODAL',
  })
  @IsOptional()
  // `'' ?? null` is `''`, and an empty string matches neither the unique
  // index's `COALESCE(cargo_category, '')` nor the report's join — it reads as
  // a category that does not exist. Blank means absent.
  @Transform(({ value }) => (value === '' ? null : value))
  @IsString()
  @MaxLength(60)
  cargoCategory?: string | null;

  @ApiPropertyOptional()
  @IsOptional()
  @IsString()
  @MaxLength(500)
  note?: string;
}