import { IsString, IsArray, ValidateNested, IsOptional, IsEnum } from 'class-validator';
import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
import { Type } from 'class-transformer';

export enum JourneyDirection {
  ONE_WAY = 'ONE_WAY',
  OUTBOUND = 'OUTBOUND',
  RETURN = 'RETURN'
}

export class PassengerSeatDto {
  @ApiProperty({ example: 'passenger-uuid', description: 'Passenger UUID' })
  @IsString() passengerId: string;

  @ApiProperty({ example: 'seat-uuid', description: 'Seat UUID assigned to this passenger' })
  @IsString() seatId: string;
}

export class HoldSeatsDto {
  @ApiProperty({ example: 'schedule-uuid', description: 'TrainSchedule UUID' })
  @IsString() scheduleId: string;

  @ApiProperty({ example: 'station-uuid', description: 'Origin station UUID — scopes the hold to a leg so the seat can be reused on non-overlapping legs' })
  @IsString() originStationId: string;

  @ApiProperty({ example: 'station-uuid', description: 'Destination station UUID for this leg' })
  @IsString() destinationStationId: string;

  @ApiPropertyOptional({ 
    enum: JourneyDirection, 
    example: JourneyDirection.OUTBOUND,
    description: 'Journey direction for round-trip bookings. ONE_WAY for single journeys, OUTBOUND/RETURN for round-trip legs. Allows same seats to be held for different directions.' 
  })
  @IsOptional()
  @IsEnum(JourneyDirection)
  journeyDirection?: JourneyDirection;

  @ApiProperty({
    type: [PassengerSeatDto],
    description: 'One entry per passenger. Each passenger is assigned exactly one seat. Duplicate passengerId or seatId within the same request is rejected.',
    example: [
      { passengerId: 'passenger-uuid-1', seatId: 'seat-uuid-1' },
      { passengerId: 'passenger-uuid-2', seatId: 'seat-uuid-2' },
    ],
  })
  @IsArray()
  @ValidateNested({ each: true })
  @Type(() => PassengerSeatDto)
  passengers: PassengerSeatDto[];
}

export class ReleaseHoldDto {
  @ApiProperty({ example: 'hold-uuid', description: 'SeatHold UUID to release' })
  @IsString() holdId: string;
}

/** Coarse bucket for *why* a seat was pulled out of sale — mirrors the Prisma
 * `SeatBlockReasonCategory` enum. The free-text `reason` stays the detail. */
export enum SeatBlockReasonCategory {
  MAINTENANCE = 'MAINTENANCE',
  VIP_RESERVED = 'VIP_RESERVED',
  SAFETY = 'SAFETY',
  OPERATIONAL = 'OPERATIONAL',
  OTHER = 'OTHER',
}

export class BlockSeatDto {
  @ApiProperty({
    example: 'Torn upholstery — awaiting replacement',
    description: 'Free-text detail explaining the block. Shown verbatim in the revenue-loss report.',
  })
  @IsString() reason: string;

  @ApiPropertyOptional({
    example: 'schedule-uuid',
    description:
      'When set, the block applies only to this schedule. Omit for a global block that pulls the seat out of sale on every schedule its coach runs on.',
  })
  @IsOptional() @IsString() scheduleId?: string;

  @ApiPropertyOptional({
    enum: SeatBlockReasonCategory,
    default: SeatBlockReasonCategory.OTHER,
    description:
      'Reporting bucket for this block. Defaults to OTHER. Drives the reason-category breakdown in the Blocked Seat Revenue Loss report.',
  })
  @IsOptional()
  @IsEnum(SeatBlockReasonCategory)
  reasonCategory?: SeatBlockReasonCategory;
}

export class SetMaintenanceDto {
  @ApiProperty({ example: 'Seat recline mechanism jammed' })
  @IsString() reason: string;
}