// src/api/services/TrainingService.ts
import { apiClient } from '../base/apiClient';
import {
  ApiResponse
} from '../types/api';

export interface TrainingJobStatus {
  job_id: string;
  tenant_id: string;
  status: 'queued' | 'running' | 'completed' | 'failed' | 'cancelled';
  progress: number;
  current_step?: string;
  started_at: string;
  completed_at?: string;
  duration_seconds?: number;
  models_trained?: Record<string, any>;
  metrics?: Record<string, any>;
  error_message?: string;
}

export interface TrainingRequest {
  force_retrain?: boolean;
  products?: string[];
  training_days?: number;
}

export interface TrainedModel {
  id: string;
  product_name: string;
  model_type: string;
  model_version: string;
  mape?: number;
  rmse?: number;
  mae?: number;
  r2_score?: number;
  training_samples?: number;
  features_used?: string[];
  is_active: boolean;
  created_at: string;
  last_used_at?: string;
}

export interface TrainingJobProgress {
  id: string;
  status: 'queued' | 'running' | 'completed' | 'failed' | 'cancelled';
  progress: number;
  current_step?: string;
  total_steps?: number;
  step_details?: string;
  estimated_completion?: string;
  logs?: string[];
}

export interface ModelMetrics {
  mape: number;
  rmse: number;
  mae: number;
  r2_score: number;
  training_samples: number;
  validation_samples: number;
  features_used: string[];
}

export interface TrainingConfiguration {
  include_weather: boolean;
  include_traffic: boolean;
  min_data_points: number;
  forecast_horizon_days: number;
  cross_validation_folds: number;
  hyperparameter_tuning: boolean;
  products?: string[];
}

export class TrainingService {
  /**
   * Start new training job
   */
  async startTraining(tenantId: string, config: TrainingConfiguration): Promise<TrainingJobStatus> {
    const response = await apiClient.post<TrainingJobStatus>(
      `/api/v1/tenants/${tenantId}/training/jobs`,
      config
    );
    return response.data!;
  }

  /**
   * Get training job status
   */
  async getTrainingStatus(tenantId: string, jobId: string): Promise<TrainingJobProgress> {
    const response = await apiClient.get<ApiResponse<TrainingJobProgress>>(
      `/api/v1/tenants/${tenantId}/training/jobs/${jobId}`
    );
    return response.data!;
  }

  /**
   * Get all training jobs
   */
  async getTrainingHistory(tenantId: string, params?: {
    page?: number;
    limit?: number;
    status?: string;
  }): Promise<{
    jobs: TrainingJobStatus[];
    total: number;
    page: number;
    pages: number;
  }> {
    const response = await apiClient.get<ApiResponse<any>>('/api/v1/training/jobs', { params });
    return response.data!;
  }

  /**
   * Cancel training job
   */
  async cancelTraining(tenantId: string, jobId: string): Promise<void> {
    await apiClient.post(`/api/v1/tenants/${tenantId}/training/jobs/${jobId}/cancel`);
  }

  /**
   * Get trained models
   */
  async getModels(tenantId: string, params?: {
    productName?: string;
    active?: boolean;
    page?: number;
    limit?: number;
  }): Promise<{
    models: TrainedModel[];
    total: number;
    page: number;
    pages: number;
  }> {
    const response = await apiClient.get<ApiResponse<any>>(`/api/v1/tenants/${tenantId}/training/models`, { params });
    return response.data!;
  }

  /**
   * Get specific model details
   */
  async getModel(tenantId: string, modelId: string): Promise<TrainedModel> {
    const response = await apiClient.get<ApiResponse<TrainedModel>>(
      `/api/v1/training/models/${modelId}`
    );
    return response.data!;
  }

  /**
   * Get model metrics
   */
  async getModelMetrics(tenantId: string, modelId: string): Promise<ModelMetrics> {
    const response = await apiClient.get<ApiResponse<ModelMetrics>>(
      `/api/v1/tenants/${tenantId}/training/models/${modelId}/metrics`
    );
    return response.data!;
  }

  /**
   * Activate/deactivate model
   */
  async toggleModelStatus(tenantId: string, modelId: string, active: boolean): Promise<TrainedModel> {
    const response = await apiClient.patch<ApiResponse<TrainedModel>>(
      `/api/v1/tenants/${tenantId}/training/models/${modelId}`,
      { is_active: active }
    );
    return response.data!;
  }

  /**
   * Delete model
   */
  async deleteModel(tenantId: string, modelId: string): Promise<void> {
    await apiClient.delete(`/api/v1/training/models/${modelId}`);
  }

  /**
   * Train specific product
   */
  async trainProduct(tenantId: string, productName: string, config?: Partial<TrainingConfiguration>): Promise<TrainingJobStatus> {
    const response = await apiClient.post<ApiResponse<TrainingJobStatus>>(
      `/api/v1/tenants/${tenantId}/training/products/train`,
      {
        product_name: productName,
        ...config,
      }
    );
    return response.data!;
  }

  /**
   * Get training statistics
   */
  async getTrainingStats(tenantId: string): Promise<{
    total_models: number;
    active_models: number;
    avg_accuracy: number;
    last_training_date: string | null;
    products_trained: number;
    training_time_avg_minutes: number;
  }> {
    const response = await apiClient.get<ApiResponse<any>>(`/api/v1/tenants/${tenantId}/training/stats`);
    return response.data!;
  }

  /**
   * Validate training data
   */
  async validateTrainingData(tenantId: string, products?: string[]): Promise<{
    valid: boolean;
    errors: string[];
    warnings: string[];
    product_data_points: Record<string, number>;
    recommendation: string;
  }> {
    const response = await apiClient.post<ApiResponse<any>>(`/api/v1/tenants/${tenantId}/training/validate`, {
      products,
    });
    return response.data!;
  }

  /**
   * Get training recommendations
   */
  async getTrainingRecommendations(tenantId: string): Promise<{
    should_retrain: boolean;
    reasons: string[];
    recommended_products: string[];
    optimal_config: TrainingConfiguration;
  }> {
    const response = await apiClient.get<ApiResponse<any>>(`/api/v1/tenants/${tenantId}/training/recommendations`);
    return response.data!;
  }

  /**
   * Get training logs
   */
  async getTrainingLogs(tenantId: string, jobId: string): Promise<string[]> {
    const response = await apiClient.get<ApiResponse<string[]>>(`/api/v1/tenants/${tenantId}/training/jobs/${jobId}/logs`);
    return response.data!;
  }

  /**
   * Export model
   */
  async exportModel(tenantId: string, modelId: string, format: 'pickle' | 'onnx' = 'pickle'): Promise<Blob> {
    const response = await apiClient.get(`/api/v1/tenants/${tenantId}/training/models/${modelId}/export`, {
      params: { format },
      responseType: 'blob',
    });
    return response as unknown as Blob;
  }
}

export const trainingService = new TrainingService();