import { DataConfig, DataStatus, DataBackup, DataRestore } from '../types/data';
import { logger } from '../utils/logger';
import { v4 as uuidv4 } from 'uuid';

/**
 * 数据管理服务
 * 负责管理系统中的数据，包括数据的备份、恢复、清理等
 */
export class DataManagementService {
  private static dataConfigs: Map<string, DataConfig> = new Map();
  private static dataStatus: Map<string, DataStatus> = new Map();
  private static backups: Map<string, DataBackup> = new Map();

  /**
   * 注册数据配置
   * @param config 数据配置
   * @returns 注册结果
   */
  static async registerData(config: DataConfig): Promise<{ success: boolean; message: string }> {
    try {
      if (this.dataConfigs.has(config.id)) {
        return { success: false, message: 'Data config already registered' };
      }

      this.dataConfigs.set(config.id, config);
      this.dataStatus.set(config.id, {
        status: 'ACTIVE',
        lastUpdated: new Date(),
        size: 0
      });

      logger.info(`Data config ${config.id} registered successfully`);
      return { success: true, message: 'Data config registered successfully' };
    } catch (error) {
      logger.error(`Error registering data config: ${error}`);
      return { success: false, message: `Error registering data config: ${error}` };
    }
  }

  /**
   * 备份数据
   * @param dataId 数据ID
   * @param backupName 备份名称
   * @returns 备份结果
   */
  static async backupData(dataId: string, backupName: string): Promise<{ success: boolean; backupId: string; message: string }> {
    try {
      const config = this.dataConfigs.get(dataId);
      if (!config) {
        return { success: false, backupId: '', message: 'Data config not found' };
      }

      // 模拟数据备份
      await new Promise(resolve => setTimeout(resolve, 2000));

      const backupId = uuidv4();
      const backup: DataBackup = {
        id: backupId,
        dataId,
        name: backupName,
        timestamp: new Date(),
        size: Math.floor(Math.random() * 1000000) + 100000,
        status: 'COMPLETED'
      };

      this.backups.set(backupId, backup);

      logger.info(`Data ${dataId} backed up successfully as ${backupId}`);
      return { success: true, backupId, message: 'Data backed up successfully' };
    } catch (error) {
      logger.error(`Error backing up data: ${error}`);
      return { success: false, backupId: '', message: `Error backing up data: ${error}` };
    }
  }

  /**
   * 恢复数据
   * @param backupId 备份ID
   * @returns 恢复结果
   */
  static async restoreData(backupId: string): Promise<{ success: boolean; message: string }> {
    try {
      const backup = this.backups.get(backupId);
      if (!backup) {
        return { success: false, message: 'Backup not found' };
      }

      const config = this.dataConfigs.get(backup.dataId);
      if (!config) {
        return { success: false, message: 'Data config not found' };
      }

      // 模拟数据恢复
      await new Promise(resolve => setTimeout(resolve, 3000));

      // 更新数据状态
      this.dataStatus.set(backup.dataId, {
        status: 'RESTORED',
        lastUpdated: new Date(),
        size: backup.size
      });

      logger.info(`Data ${backup.dataId} restored successfully from backup ${backupId}`);
      return { success: true, message: 'Data restored successfully' };
    } catch (error) {
      logger.error(`Error restoring data: ${error}`);
      return { success: false, message: `Error restoring data: ${error}` };
    }
  }

  /**
   * 清理数据
   * @param dataId 数据ID
   * @param retentionDays 保留天数
   * @returns 清理结果
   */
  static async cleanData(dataId: string, retentionDays: number): Promise<{ success: boolean; cleanedSize: number; message: string }> {
    try {
      const config = this.dataConfigs.get(dataId);
      if (!config) {
        return { success: false, cleanedSize: 0, message: 'Data config not found' };
      }

      // 模拟数据清理
      await new Promise(resolve => setTimeout(resolve, 1500));

      const cleanedSize = Math.floor(Math.random() * 500000) + 50000;

      // 更新数据状态
      const status = this.dataStatus.get(dataId);
      if (status) {
        status.size = Math.max(0, status.size - cleanedSize);
        status.lastUpdated = new Date();
        this.dataStatus.set(dataId, status);
      }

      logger.info(`Data ${dataId} cleaned successfully, removed ${cleanedSize} bytes`);
      return { success: true, cleanedSize, message: 'Data cleaned successfully' };
    } catch (error) {
      logger.error(`Error cleaning data: ${error}`);
      return { success: false, cleanedSize: 0, message: `Error cleaning data: ${error}` };
    }
  }

  /**
   * 获取数据状态
   * @param dataId 数据ID
   * @returns 数据状态
   */
  static async getDataStatus(dataId: string): Promise<DataStatus | null> {
    try {
      const status = this.dataStatus.get(dataId);
      if (!status) {
        return null;
      }

      // 更新最后更新时间
      status.lastUpdated = new Date();
      this.dataStatus.set(dataId, status);

      return status;
    } catch (error) {
      logger.error(`Error getting data status: ${error}`);
      return null;
    }
  }

  /**
   * 获取所有数据配置列表
   * @returns 数据配置列表
   */
  static async listDataConfigs(): Promise<Array<{ id: string; config: DataConfig; status: DataStatus }>> {
    try {
      const configs: Array<{ id: string; config: DataConfig; status: DataStatus }> = [];

      for (const [id, config] of this.dataConfigs.entries()) {
        const status = this.dataStatus.get(id) || {
          status: 'UNKNOWN',
          lastUpdated: new Date(),
          size: 0
        };
        configs.push({ id, config, status });
      }

      return configs;
    } catch (error) {
      logger.error(`Error listing data configs: ${error}`);
      return [];
    }
  }

  /**
   * 获取备份列表
   * @param dataId 数据ID（可选）
   * @returns 备份列表
   */
  static async listBackups(dataId?: string): Promise<DataBackup[]> {
    try {
      const backups: DataBackup[] = [];

      for (const backup of this.backups.values()) {
        if (!dataId || backup.dataId === dataId) {
          backups.push(backup);
        }
      }

      // 按时间倒序排序
      backups.sort((a, b) => b.timestamp.getTime() - a.timestamp.getTime());

      return backups;
    } catch (error) {
      logger.error(`Error listing backups: ${error}`);
      return [];
    }
  }

  /**
   * 删除备份
   * @param backupId 备份ID
   * @returns 删除结果
   */
  static async deleteBackup(backupId: string): Promise<{ success: boolean; message: string }> {
    try {
      const backup = this.backups.get(backupId);
      if (!backup) {
        return { success: false, message: 'Backup not found' };
      }

      this.backups.delete(backupId);

      logger.info(`Backup ${backupId} deleted successfully`);
      return { success: true, message: 'Backup deleted successfully' };
    } catch (error) {
      logger.error(`Error deleting backup: ${error}`);
      return { success: false, message: `Error deleting backup: ${error}` };
    }
  }

  /**
   * 导出数据
   * @param dataId 数据ID
   * @param format 导出格式
   * @returns 导出结果
   */
  static async exportData(dataId: string, format: 'json' | 'csv' | 'excel'): Promise<{ success: boolean; exportUrl: string; message: string }> {
    try {
      const config = this.dataConfigs.get(dataId);
      if (!config) {
        return { success: false, exportUrl: '', message: 'Data config not found' };
      }

      // 模拟数据导出
      await new Promise(resolve => setTimeout(resolve, 2000));

      const exportUrl = `/api/data/export/${dataId}/${uuidv4()}.${format}`;

      logger.info(`Data ${dataId} exported successfully in ${format} format`);
      return { success: true, exportUrl, message: 'Data exported successfully' };
    } catch (error) {
      logger.error(`Error exporting data: ${error}`);
      return { success: false, exportUrl: '', message: `Error exporting data: ${error}` };
    }
  }

  /**
   * 导入数据
   * @param dataId 数据ID
   * @param fileUrl 文件URL
   * @returns 导入结果
   */
  static async importData(dataId: string, fileUrl: string): Promise<{ success: boolean; importedSize: number; message: string }> {
    try {
      const config = this.dataConfigs.get(dataId);
      if (!config) {
        return { success: false, importedSize: 0, message: 'Data config not found' };
      }

      // 模拟数据导入
      await new Promise(resolve => setTimeout(resolve, 3000));

      const importedSize = Math.floor(Math.random() * 1000000) + 100000;

      // 更新数据状态
      const status = this.dataStatus.get(dataId);
      if (status) {
        status.size += importedSize;
        status.lastUpdated = new Date();
        this.dataStatus.set(dataId, status);
      }

      logger.info(`Data ${dataId} imported successfully, added ${importedSize} bytes`);
      return { success: true, importedSize, message: 'Data imported successfully' };
    } catch (error) {
      logger.error(`Error importing data: ${error}`);
      return { success: false, importedSize: 0, message: `Error importing data: ${error}` };
    }
  }
}
