import { 
    fetchDataFromTable, 
    insertDataIntoTable, 
    updateDataInTable 
  } from '../../db/supabaseHelper';
  import { createLogger } from '../../utils/logger';
  import { v4 as uuidv4 } from 'uuid';
  import { supabase } from '../../db/supabase';
  import { BotContext } from '../types/botTypes';
  import { getBotIdFromContext } from '../../utils/botUtils';
  
  const logger = createLogger('AuthService');

  interface UserBotTelegraf {
    id?: number; // SERIAL in SQL becomes number in TypeScript
    telegramId: number; // BIGINT in SQL becomes number in TypeScript
    username?: string | null; // VARCHAR(255), optional
    firstName?: string | null; // VARCHAR(255), matches SQL column name
    lastName?: string | null; // VARCHAR(255), matches SQL column name
    email: string; // VARCHAR(255) NOT NULL
    passwordHash: string; // VARCHAR(255) NOT NULL, matches SQL column name
    language?: string; // VARCHAR(10) DEFAULT 'en'
    role?: string; // VARCHAR(10) DEFAULT 'user'
    balance?: number; // DECIMAL(10, 2) DEFAULT 0
    isBanned?: boolean; // BOOLEAN DEFAULT false
    lastLogin?: Date | string | null; // TIMESTAMPTZ (can be Date, ISO string, or null)
    botId?: string | null; // UUID (string in TypeScript)
    createdAt?: Date | string; // TIMESTAMPTZ DEFAULT NOW()
    updatedAt?: Date | string; // TIMESTAMPTZ DEFAULT NOW()
  }
  
  export class AuthService {
    private static instance: AuthService;
  
    private constructor() {
      // Private constructor for singleton pattern
    }
  
    public static getInstance(): AuthService {
      if (!AuthService.instance) {
        AuthService.instance = new AuthService();
      }
      return AuthService.instance;
    }
  
    private generatePassword(): string {
      return uuidv4().replace(/-/g, '').substring(0, 12);
    }
  
    public async hashPassword(password: string): Promise<string> {
      const encoder = new TextEncoder();
      const data = encoder.encode(password);
      const hashBuffer = await crypto.subtle.digest('SHA-256', data);
      const hashArray = Array.from(new Uint8Array(hashBuffer));
      return hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
    }
  
    private generateEmail(telegramId: number, ctx: BotContext): string {
      const botData = ctx.botData;
      const suffix = botData?.suffix_email || 'saerosms.com';
      return `user_${telegramId}@${suffix}`;
    }
  
    public async createUser(telegramId: number, name: string, ctx: BotContext): Promise<{ user: UserBotTelegraf; password: string }> {
      try {
        const botId = getBotIdFromContext(ctx);
        if (!botId) {
          throw new Error('Could not determine bot ID from context');
        }

        const email = this.generateEmail(telegramId, ctx);
        const password = this.generatePassword();
        const passwordHash = await this.hashPassword(password);
  
        const userData: Omit<UserBotTelegraf, 'id'> = {
          telegramId: telegramId,
          firstName: name,
          email,
          passwordHash: passwordHash,
          botId: botId,
          balance: 0,
          language: 'ar',
          role: 'user',
          isBanned: false
        };
  
        const user = await insertDataIntoTable('users_bot_telegram', userData);
        
        logger.info(`User ${telegramId} created successfully for bot ${botId}`);
        return { user, password };
  
      } catch (error: any) {
        logger.error(`Error creating user ${telegramId}: ${error.message}`);
        throw new Error(`Failed to create user: ${error.message}`);
      }
    }
  
    private loggedInUsers: Map<string, boolean> = new Map();
  
    private generateUserKey(telegramId: number, ctx: BotContext): string {
      const botId = getBotIdFromContext(ctx);
      if (!botId) {
        throw new Error('Could not determine bot ID from context');
      }
      return `${telegramId}_${botId}`;
    }
  
    public setUserLoggedIn(telegramId: number, ctx: BotContext, isLoggedIn: boolean = true): void {
      const key = this.generateUserKey(telegramId, ctx);
      const botId = getBotIdFromContext(ctx);
      this.loggedInUsers.set(key, isLoggedIn);
      logger.info(`User ${telegramId} for bot ${botId} login state set to ${isLoggedIn}`);
    }
  
    public isUserLoggedIn(telegramId: number, ctx: BotContext): boolean {
      const key = this.generateUserKey(telegramId, ctx);
      return this.loggedInUsers.get(key) || false;
    }
  
    public async loginUser(telegramId: number, ctx: BotContext): Promise<UserBotTelegraf | null> {
      try {
        const botId = getBotIdFromContext(ctx);
        if (!botId) {
          throw new Error('Could not determine bot ID from context');
        }

        const { data: user, error } = await supabase
          .from('users_bot_telegram')
          .select('*')
          .eq('telegram_id', telegramId)
          .eq('bot_id', botId)
          .single();

        if (error) {
          if (error.code === 'PGRST116') {
            return null; // User not found
          }
          throw error;
        }

        if (user) {
          this.setUserLoggedIn(telegramId, ctx, true);
          return user;
        }

        return null;
      } catch (error) {
        logger.error('Error in loginUser:', error);
        return null;
      }
    }
  
    public async getUserById(userId: string): Promise<UserBotTelegraf | null> {
      try {
        const { data: user, error } = await supabase
          .from('users_bot_telegram')
          .select('*')
          .eq('id', userId)
          .single();

        if (error) {
          if (error.code === 'PGRST116') {
            return null;
          }
          throw error;
        }

        return user;
      } catch (error: any) {
        logger.error(`Error fetching user ${userId}: ${error.message}`);
        throw new Error(`Failed to get user: ${error.message}`);
      }
    }
  
    async getUserByTelegramId(telegramId: number, ctx: BotContext): Promise<UserBotTelegraf | null> {
      try {
        const botId = getBotIdFromContext(ctx);
        if (!botId) {
          throw new Error('Could not determine bot ID from context');
        }

        const { data: user, error } = await supabase
          .from('users_bot_telegram')
          .select('*')
          .eq('telegram_id', telegramId)
          .eq('bot_id', botId)
          .single();
        
        if (error) {
          if (error.code === 'PGRST116') {
            return null;
          }
          throw error;
        }

        return user;
      } catch (error: any) {
        logger.error(`Error getting user by Telegram ID: ${error.message}`);
        return null;
      }
    }
  
    async updateUserBalance(telegramId: number, ctx: BotContext, newBalance: number): Promise<boolean> {
      try {
        const botId = getBotIdFromContext(ctx);
        if (!botId) {
          throw new Error('Could not determine bot ID from context');
        }

        const { error } = await supabase
          .from('users_bot_telegram')
          .update({ balance: newBalance })
          .eq('telegram_id', telegramId)
          .eq('bot_id', botId);
        
        if (error) throw error;
        return true;
      } catch (error: any) {
        logger.error(`Error updating user balance: ${error.message}`);
        return false;
      }
    }
  }
  
  // Singleton instance
  export const authService = AuthService.getInstance();