/**
 * Ziwei Chart Engine Agent (紫微排盤引擎)
 *
 * Responsible for:
 * - Converting birth information to Ziwei chart calculations
 * - Computing all timing cycles (base, xuan, decade, annual, monthly, daily luck)
 * - Validating astronomical/astrological accuracy
 *
 * Input: Birth data (date, time, location, gender)
 * Output: Complete BirthChart JSON following the schema
 */

import {
  BirthInfo,
  BirthChart,
  ChartType,
  Palace,
  HeavenlyStem,
  EarthlyBranch,
  Element,
  NaYinElement,
  PrimaryStar,
  StarInfo,
  StarBrightness,
  PalaceInfo,
  DecadeLuck,
  AnnualLuck,
  MonthlyLuck,
  DailyLuck,
  Pattern,
  SixtyStarSystem,
  FourTransformations,
  Transformation
} from '../knowledge/schema/ziwei-types';

// ============================================================================
// AGENT INPUT/OUTPUT INTERFACES
// ============================================================================

/**
 * Input for ChartEngineAgent
 */
export interface ChartEngineInput {
  // Birth Data
  birth_info: BirthInfo;

  // Configuration options
  options?: {
    include_decade_luck?: boolean;          // Default: true
    include_annual_luck?: boolean;          // Default: true
    include_monthly_luck?: boolean;         // Default: false (can be expensive)
    include_daily_luck?: boolean;           // Default: false
    decade_luck_years?: number;             // How many decades to calculate (default: 8)
    annual_luck_years?: number;             // Years into future to calculate (default: 20)
    algorithm_version?: 'zhongzhou_1952' | 'zhongzhou_1953' | 'zhongzhou_modern';  // Default: 'zhongzhou_modern'
  };
}

/**
 * Output for ChartEngineAgent - Success case
 */
export interface ChartEngineSuccess {
  status: 'success';
  chart: BirthChart;
  calculation_duration_ms: number;
  notes?: string[];
}

/**
 * Output for ChartEngineAgent - Error case
 */
export interface ChartEngineError {
  status: 'error';
  error_code: string;
  error_message: string;
  details?: Record<string, any>;
}

export type ChartEngineOutput = ChartEngineSuccess | ChartEngineError;

// ============================================================================
// CHART ENGINE AGENT CLASS
// ============================================================================

/**
 * ChartEngineAgent - Converts birth data to complete Ziwei birth chart
 *
 * This is an agent interface specification. Actual implementation would:
 * 1. Parse birth information and validate date/time
 * 2. Convert between calendar systems (Gregorian ↔ Lunar)
 * 3. Calculate Four Pillars (八字)
 * 4. Determine palace positions and star distributions
 * 5. Compute timing cycles and transformations
 * 6. Apply Zhongzhou school specific rules
 * 7. Output complete BirthChart JSON
 */
export class ChartEngineAgent {
  /**
   * Main method: Generate complete birth chart
   *
   * @param input - Birth information and calculation options
   * @returns Complete birth chart or error information
   *
   * @example
   * const agent = new ChartEngineAgent();
   * const result = await agent.generateChart({
   *   birth_info: {
   *     birth_datetime: {
   *       year: 1985,
   *       month: 3,
   *       day: 15,
   *       hour: 14,
   *       minute: 30
   *     },
   *     calendar_type: 'gregorian',
   *     location: {
   *       city: 'Beijing',
   *       country: 'China',
   *       latitude: 39.9042,
   *       longitude: 116.4074,
   *       timezone: 'Asia/Shanghai'
   *     },
   *     gender: 'male'
   *   },
   *   options: {
   *     include_decade_luck: true,
   *     include_annual_luck: true,
   *     algorithm_version: 'zhongzhou_modern'
   *   }
   * });
   */
  async generateChart(input: ChartEngineInput): Promise<ChartEngineOutput> {
    // Implementation stub - actual logic would go here
    const startTime = Date.now();

    try {
      // Step 1: Validate input
      this.validateBirthInfo(input.birth_info);

      // Step 2: Parse options
      const options = {
        include_decade_luck: input.options?.include_decade_luck ?? true,
        include_annual_luck: input.options?.include_annual_luck ?? true,
        include_monthly_luck: input.options?.include_monthly_luck ?? false,
        include_daily_luck: input.options?.include_daily_luck ?? false,
        decade_luck_years: input.options?.decade_luck_years ?? 8,
        annual_luck_years: input.options?.annual_luck_years ?? 20,
        algorithm_version: input.options?.algorithm_version ?? 'zhongzhou_modern'
      };

      // Step 3: Convert calendar if needed
      const lunarDate = await this.convertToLunarCalendar(
        input.birth_info.birth_datetime,
        input.birth_info.calendar_type
      );

      // Step 4: Calculate Four Pillars (八字)
      const ganZhi = this.calculateFourPillars(lunarDate);

      // Step 5: Calculate base chart
      const baseChart = await this.calculateBaseChart(ganZhi, input.birth_info);

      // Step 6: Calculate Xuan patterns
      const xuanPatterns = await this.calculateXuanPatterns(baseChart);

      // Step 7: Calculate timing cycles
      const decadeLuck = options.include_decade_luck
        ? await this.calculateDecadeLuck(baseChart, ganZhi, options.decade_luck_years)
        : [];

      const annualLuck = options.include_annual_luck
        ? await this.calculateAnnualLuck(baseChart, ganZhi, options.annual_luck_years)
        : [];

      const monthlyLuck = options.include_monthly_luck
        ? await this.calculateMonthlyLuck(baseChart, annualLuck)
        : [];

      const dailyLuck = options.include_daily_luck
        ? await this.calculateDailyLuck(baseChart, monthlyLuck)
        : [];

      // Step 8: Assemble complete chart
      const chart: BirthChart = {
        id: this.generateChartId(),
        chart_id_code: `ZW-${new Date().getFullYear()}-${Math.random().toString(36).substr(2, 9).toUpperCase()}`,
        created_at: new Date().toISOString(),
        updated_at: new Date().toISOString(),
        birth_info: input.birth_info,
        lunar_date: lunarDate,
        gan_zhi: ganZhi,
        base_chart: baseChart,
        xuan_patterns: xuanPatterns,
        decade_luck: decadeLuck,
        annual_luck: annualLuck,
        monthly_luck: monthlyLuck,
        daily_luck: dailyLuck,
        calculation_metadata: {
          used_algorithm: options.algorithm_version,
          time_zone_applied: input.birth_info.location?.timezone || 'UTC',
          daylight_saving_applied: input.birth_info.is_daylight_saving ?? false,
          precision_level: 'high'
        }
      };

      const duration = Date.now() - startTime;

      return {
        status: 'success',
        chart,
        calculation_duration_ms: duration,
        notes: [
          `Chart calculated using ${options.algorithm_version} algorithm`,
          `Included decade luck calculations for ${options.decade_luck_years} decades`,
          `Included annual luck calculations for ${options.annual_luck_years} years`
        ]
      };
    } catch (error) {
      const duration = Date.now() - startTime;
      return {
        status: 'error',
        error_code: 'CHART_GENERATION_FAILED',
        error_message: `Failed to generate chart: ${error instanceof Error ? error.message : 'Unknown error'}`,
        details: {
          calculation_time_ms: duration,
          input: input
        }
      };
    }
  }

  /**
   * Validate birth information completeness
   */
  private validateBirthInfo(birthInfo: BirthInfo): void {
    if (!birthInfo.birth_datetime) {
      throw new Error('Birth datetime is required');
    }
    if (!birthInfo.calendar_type) {
      throw new Error('Calendar type (gregorian or lunar) is required');
    }
    if (!birthInfo.gender) {
      throw new Error('Gender is required');
    }
    // Additional validations for date ranges, timezone, etc.
  }

  /**
   * Convert between Gregorian and Lunar calendar
   * In production, this would use astronomical/calendar libraries
   */
  private async convertToLunarCalendar(
    datetime: BirthInfo['birth_datetime'],
    calendarType: 'gregorian' | 'lunar'
  ): Promise<BirthInfo['lunar_date']> {
    // Stub: In real implementation, use LuniSolar calendar library
    // This is complex astronomical calculation
    return {
      year: datetime.year,
      month: datetime.month,
      day: datetime.day
    };
  }

  /**
   * Calculate Four Pillars (八字) from lunar datetime
   * Returns Year, Month, Day, Hour pillars with stems and branches
   */
  private calculateFourPillars(lunarDate: BirthInfo['lunar_date']): BirthChart['gan_zhi'] {
    // Stub implementation
    // In real implementation: use Heavenly Stems (干) and Earthly Branches (支) calculations
    return {
      year_pillar: { stem: HeavenlyStem.JIA, branch: EarthlyBranch.ZI },
      month_pillar: { stem: HeavenlyStem.BING, branch: EarthlyBranch.YIN },
      day_pillar: { stem: HeavenlyStem.WU, branch: EarthlyBranch.CHEN },
      hour_pillar: { stem: HeavenlyStem.GENG, branch: EarthlyBranch.WU }
    };
  }

  /**
   * Calculate base chart (本命盤)
   * Determine palace positions, star distributions, and fundamental patterns
   */
  private async calculateBaseChart(
    ganZhi: BirthChart['gan_zhi'],
    birthInfo: BirthInfo
  ): Promise<BirthChart['base_chart']> {
    // Stub implementation
    // Real implementation would:
    // 1. Calculate Ming palace (命宮) position based on hour pillar
    // 2. Determine other palace positions in sequence
    // 3. Place primary stars according to Zhongzhou rules
    // 4. Place secondary stars and calamity stars
    // 5. Identify patterns (殺破狼, etc.)

    return {
      palaces: [],
      stars_by_palace: new Map(),
      five_element_distribution: {
        [Element.METAL]: 2,
        [Element.WOOD]: 1,
        [Element.WATER]: 2,
        [Element.FIRE]: 1,
        [Element.EARTH]: 1
      },
      ruling_element: Element.METAL,
      fundamental_pattern: Pattern.ZI_FU_ZHAO_YUAN
    };
  }

  /**
   * Calculate Xuan configuration (玄局)
   * Identify patterns and sixty-star systems relevant to the chart
   */
  private async calculateXuanPatterns(
    baseChart: BirthChart['base_chart']
  ): Promise<BirthChart['xuan_patterns']> {
    // Stub implementation
    return {
      major_patterns: [Pattern.ZI_FU_ZHAO_YUAN],
      sixty_star_systems: [SixtyStarSystem.SYSTEM_1],
      configuration_stability: 'stable',
      description: 'This is a stable Xuan configuration'
    };
  }

  /**
   * Calculate decade luck (大限)
   * 10-year periods from birth to old age
   */
  private async calculateDecadeLuck(
    baseChart: BirthChart['base_chart'],
    ganZhi: BirthChart['gan_zhi'],
    numberOfDecades: number
  ): Promise<DecadeLuck[]> {
    // Stub implementation
    const decadeLucks: DecadeLuck[] = [];

    for (let i = 1; i <= numberOfDecades; i++) {
      decadeLucks.push({
        decade_number: i,
        age_start: (i - 1) * 10,
        age_end: i * 10,
        palace_governing: Palace.MING,
        stars_involved: [],
        four_transformations_annual: [],
        patterns_active: []
      });
    }

    return decadeLucks;
  }

  /**
   * Calculate annual luck (流年)
   * Year-by-year trend analysis
   */
  private async calculateAnnualLuck(
    baseChart: BirthChart['base_chart'],
    ganZhi: BirthChart['gan_zhi'],
    numberOfYears: number
  ): Promise<AnnualLuck[]> {
    // Stub implementation
    const annualLucks: AnnualLuck[] = [];

    const currentYear = new Date().getFullYear();

    for (let i = 0; i < numberOfYears; i++) {
      const year = currentYear + i;
      annualLucks.push({
        year,
        year_stem: HeavenlyStem.JIA,
        year_branch: EarthlyBranch.ZI,
        palace_governing: Palace.MING,
        flowing_stars: [],
        four_transformations: [],
        interaction_with_decade: ''
      });
    }

    return annualLucks;
  }

  /**
   * Calculate monthly luck (流月)
   * Month-by-month trend within each year
   */
  private async calculateMonthlyLuck(
    baseChart: BirthChart['base_chart'],
    annualLuck: AnnualLuck[]
  ): Promise<MonthlyLuck[]> {
    // Stub implementation - would expand annual luck into monthly
    return [];
  }

  /**
   * Calculate daily luck (流日)
   * Day-by-day trend for detailed analysis
   */
  private async calculateDailyLuck(
    baseChart: BirthChart['base_chart'],
    monthlyLuck: MonthlyLuck[]
  ): Promise<DailyLuck[]> {
    // Stub implementation - would expand monthly luck into daily
    return [];
  }

  /**
   * Generate unique chart ID
   */
  private generateChartId(): string {
    return `chart-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
  }

  /**
   * Optional: Validate chart integrity after generation
   */
  async validateChart(chart: BirthChart): Promise<{ valid: boolean; errors: string[] }> {
    const errors: string[] = [];

    // Check basic structure
    if (!chart.birth_info) errors.push('Missing birth_info');
    if (!chart.base_chart) errors.push('Missing base_chart');
    if (!chart.gan_zhi) errors.push('Missing gan_zhi');

    // Check base chart structure
    if (chart.base_chart && chart.base_chart.palaces.length !== 12) {
      errors.push('Base chart must have exactly 12 palaces');
    }

    return {
      valid: errors.length === 0,
      errors
    };
  }
}

export default ChartEngineAgent;