import { IsString, IsOptional, IsArray, IsInt, Min, IsUUID, ValidateNested, ArrayMaxSize, IsNotEmpty, MaxLength } from 'class-validator';
import { Type } from 'class-transformer';
import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';

export class OpenTabItemDto {
  @ApiProperty({ example: 'Cola' })
  @IsString()
  @IsNotEmpty()
  @MaxLength(200)
  productName: string;

  @ApiProperty({ example: 10 })
  @IsInt()
  @Min(0)
  quantity: number;

  @ApiProperty({ example: 250 })
  @IsInt()
  @Min(0)
  unitPriceInCents: number;
}

export class OpenTabDto {
  @ApiProperty({ example: 'local-tab-uuid' })
  @IsString()
  @IsNotEmpty()
  id: string;

  @ApiProperty({ example: 'Jan' })
  @IsString()
  customerName: string;

  @ApiProperty({ example: 5 })
  @IsInt()
  @Min(0)
  version: number;

  @ApiProperty({ example: 2450 })
  @IsInt()
  @Min(0)
  totalInCents: number;

  @ApiProperty({ example: 3 })
  @IsInt()
  @Min(0)
  itemCount: number;

  @ApiPropertyOptional({ type: [OpenTabItemDto], description: 'Lines on the tab; omitted by older app versions' })
  @IsOptional()
  @IsArray()
  @ArrayMaxSize(500)
  @ValidateNested({ each: true })
  @Type(() => OpenTabItemDto)
  items?: OpenTabItemDto[];
}

export class SyncDto {
  @ApiProperty({ example: 'uuid' })
  @IsUUID()
  deviceId: string;

  @ApiPropertyOptional({ example: 'cursor-value' })
  @IsOptional()
  @IsString()
  cursor?: string;

  @ApiPropertyOptional({ description: 'Where the settlements feed left off; absent on the first sync after pairing' })
  @IsOptional()
  @IsString()
  @MaxLength(100)
  settlementsCursor?: string;

  // The server holds the tabs: only used once, to take over the terminal's tabs on its first sync
  @ApiProperty({ type: [OpenTabDto] })
  @IsArray()
  @ArrayMaxSize(1000)
  @ValidateNested({ each: true })
  @Type(() => OpenTabDto)
  openTabs: OpenTabDto[];

  // Validated one by one in the service: a bad event is rejected on its own instead of failing the sync
  @ApiPropertyOptional({ description: 'TabEventDto[]: what happened on tabs since the last acknowledged sync' })
  @IsOptional()
  @IsArray()
  @ArrayMaxSize(1000)
  events?: unknown[];

  // Validated one by one in the service, like events
  @ApiPropertyOptional({
    description: "ReportedProductDto[]: the terminal's complete product catalog with stock. Omitted by app versions without stock",
  })
  @IsOptional()
  @IsArray()
  @ArrayMaxSize(2000)
  products?: unknown[];

  @ApiPropertyOptional({ description: 'StockAdjustmentResultDto[]: outcomes of stock adjustments the terminal received' })
  @IsOptional()
  @IsArray()
  @ArrayMaxSize(1000)
  stockAdjustmentResults?: unknown[];
}