import { IsString, IsOptional, IsEnum, IsNumber, IsDate, IsArray, IsObject, Min, ValidateNested, IsBoolean } from 'class-validator';
import { Type } from 'class-transformer';
import { ApiProperty, ApiPropertyOptional, PartialType } from '@nestjs/swagger';
import { GoalType, MetricType, PeriodType, DataSource, GoalStatus, SourceConfig, Milestone } from '../entities/definition.entity';

// ─────────────────────────────────────────────
// Milestone DTO
// ─────────────────────────────────────────────

export class MilestoneDto {
  @ApiProperty({ example: 50 })
  @IsNumber()
  @Min(0)
  percentage: number;

  @ApiProperty({ example: true })
  @IsBoolean()
  notify: boolean;
}

// ─────────────────────────────────────────────
// Source Config DTO
// ─────────────────────────────────────────────

export class SourceConfigDto {
  @ApiPropertyOptional({ example: 'sales' })
  @IsOptional()
  @IsString()
  module?: string;

  @ApiPropertyOptional({ example: 'opportunities' })
  @IsOptional()
  @IsString()
  entity?: string;

  @ApiPropertyOptional({ example: { status: 'won' } })
  @IsOptional()
  @IsObject()
  filter?: Record<string, unknown>;

  @ApiPropertyOptional({ enum: ['sum', 'count', 'avg'] })
  @IsOptional()
  @IsString()
  aggregation?: 'sum' | 'count' | 'avg';

  @ApiPropertyOptional({ example: 'amount' })
  @IsOptional()
  @IsString()
  field?: string;
}

// ─────────────────────────────────────────────
// Create Definition DTO
// ─────────────────────────────────────────────

export class CreateDefinitionDto {
  @ApiProperty({ example: 'Q1 Sales Target' })
  @IsString()
  name: string;

  @ApiPropertyOptional({ example: 'Achieve $100,000 in closed deals' })
  @IsOptional()
  @IsString()
  description?: string;

  @ApiPropertyOptional({ example: 'sales' })
  @IsOptional()
  @IsString()
  category?: string;

  @ApiPropertyOptional({ enum: GoalType, default: GoalType.TARGET })
  @IsOptional()
  @IsEnum(GoalType)
  type?: GoalType;

  @ApiPropertyOptional({ enum: MetricType, default: MetricType.NUMBER })
  @IsOptional()
  @IsEnum(MetricType)
  metric?: MetricType;

  @ApiProperty({ example: 100000 })
  @IsNumber()
  @Min(0)
  targetValue: number;

  @ApiPropertyOptional({ example: 'USD' })
  @IsOptional()
  @IsString()
  unit?: string;

  @ApiPropertyOptional({ enum: PeriodType, default: PeriodType.MONTHLY })
  @IsOptional()
  @IsEnum(PeriodType)
  period?: PeriodType;

  @ApiProperty({ example: '2026-01-01' })
  @Type(() => Date)
  @IsDate()
  startsAt: Date;

  @ApiProperty({ example: '2026-03-31' })
  @Type(() => Date)
  @IsDate()
  endsAt: Date;

  @ApiPropertyOptional({ enum: DataSource, default: DataSource.MANUAL })
  @IsOptional()
  @IsEnum(DataSource)
  source?: DataSource;

  @ApiPropertyOptional({ type: SourceConfigDto })
  @IsOptional()
  @ValidateNested()
  @Type(() => SourceConfigDto)
  sourceConfig?: SourceConfigDto;

  @ApiPropertyOptional({ type: [MilestoneDto] })
  @IsOptional()
  @IsArray()
  @ValidateNested({ each: true })
  @Type(() => MilestoneDto)
  milestones?: MilestoneDto[];

  @ApiPropertyOptional({ enum: GoalStatus, default: GoalStatus.DRAFT })
  @IsOptional()
  @IsEnum(GoalStatus)
  status?: GoalStatus;

  @ApiPropertyOptional({ type: [String], example: ['sales', 'q1'] })
  @IsOptional()
  @IsArray()
  @IsString({ each: true })
  tags?: string[];
}

// ─────────────────────────────────────────────
// Update Definition DTO
// ─────────────────────────────────────────────

export class UpdateDefinitionDto extends PartialType(CreateDefinitionDto) {}

// ─────────────────────────────────────────────
// Update Status DTO
// ─────────────────────────────────────────────

export class UpdateDefinitionStatusDto {
  @ApiProperty({ enum: GoalStatus })
  @IsEnum(GoalStatus)
  status: GoalStatus;
}

// ─────────────────────────────────────────────
// Definition Response DTO
// ─────────────────────────────────────────────

export class DefinitionResponseDto {
  @ApiProperty()
  id: string;

  @ApiProperty()
  tenantId: string;

  @ApiProperty()
  name: string;

  @ApiPropertyOptional()
  description: string | null;

  @ApiPropertyOptional()
  category: string | null;

  @ApiProperty({ enum: GoalType })
  type: GoalType;

  @ApiProperty({ enum: MetricType })
  metric: MetricType;

  @ApiProperty()
  targetValue: number;

  @ApiPropertyOptional()
  unit: string | null;

  @ApiProperty({ enum: PeriodType })
  period: PeriodType;

  @ApiProperty()
  startsAt: Date;

  @ApiProperty()
  endsAt: Date;

  @ApiProperty({ enum: DataSource })
  source: DataSource;

  @ApiProperty()
  sourceConfig: SourceConfig;

  @ApiProperty({ type: [MilestoneDto] })
  milestones: Milestone[];

  @ApiProperty({ enum: GoalStatus })
  status: GoalStatus;

  @ApiProperty({ type: [String] })
  tags: string[];

  @ApiProperty()
  createdAt: Date;

  @ApiProperty()
  updatedAt: Date;

  @ApiPropertyOptional()
  createdBy: string | null;

  @ApiPropertyOptional()
  assignmentCount?: number;
}

// ─────────────────────────────────────────────
// Definition Filters DTO
// ─────────────────────────────────────────────

export class DefinitionFiltersDto {
  @ApiPropertyOptional({ enum: GoalStatus })
  @IsOptional()
  @IsEnum(GoalStatus)
  status?: GoalStatus;

  @ApiPropertyOptional({ enum: PeriodType })
  @IsOptional()
  @IsEnum(PeriodType)
  period?: PeriodType;

  @ApiPropertyOptional()
  @IsOptional()
  @IsString()
  category?: string;

  @ApiPropertyOptional()
  @IsOptional()
  @IsString()
  search?: string;

  @ApiPropertyOptional()
  @IsOptional()
  @Type(() => Date)
  @IsDate()
  activeOn?: Date;

  @ApiPropertyOptional({ example: 'createdAt' })
  @IsOptional()
  @IsString()
  sortBy?: string;

  @ApiPropertyOptional({ enum: ['ASC', 'DESC'], default: 'DESC' })
  @IsOptional()
  @IsString()
  sortOrder?: 'ASC' | 'DESC';

  @ApiPropertyOptional({ default: 1 })
  @IsOptional()
  @Type(() => Number)
  @IsNumber()
  page?: number;

  @ApiPropertyOptional({ default: 20 })
  @IsOptional()
  @Type(() => Number)
  @IsNumber()
  limit?: number;
}