import SQLite from "react-native-sqlite-storage";
import { RegisterCredentials, User } from "../types";

SQLite.DEBUG(true);
SQLite.enablePromise(true);

class DatabaseService {
  private db: SQLite.SQLiteDatabase | null = null;

  async initDatabase(): Promise<void> {
    try {
      this.db = await SQLite.openDatabase({
        name: "AuthApp.db",
        location: "default",
      });

      await this.db.executeSql(`
        CREATE TABLE IF NOT EXISTS users (
          id INTEGER PRIMARY KEY AUTOINCREMENT,
          email TEXT UNIQUE NOT NULL,
          password TEXT NOT NULL,
          firstName TEXT NOT NULL,
          lastName TEXT NOT NULL,
          createdAt TEXT NOT NULL
        )
      `);

      console.log("Database initialized successfully");
    } catch (error) {
      console.error("Database initialization failed:", error);
      throw error;
    }
  }

  async registerUser(credentials: RegisterCredentials): Promise<User> {
    if (!this.db) {
      throw new Error("Database not initialized");
    }

    try {
      const createdAt = new Date().toISOString();

      const result = await this.db.executeSql(
        "INSERT INTO users (email, password, firstName, lastName, createdAt) VALUES (?, ?, ?, ?, ?)",
        [
          credentials.email,
          credentials.password,
          credentials.firstName,
          credentials.lastName,
          createdAt,
        ]
      );

      const userId = result[0].insertId;

      return {
        id: userId,
        email: credentials.email,
        password: credentials.password,
        firstName: credentials.firstName,
        lastName: credentials.lastName,
        createdAt,
      };
    } catch (error) {
      console.error("User registration failed:", error);
      throw error;
    }
  }

  async loginUser(email: string, password: string): Promise<User | null> {
    if (!this.db) {
      throw new Error("Database not initialized");
    }

    try {
      const result = await this.db.executeSql(
        "SELECT * FROM users WHERE email = ? AND password = ?",
        [email, password]
      );

      if (result[0].rows.length > 0) {
        const userData = result[0].rows.item(0);
        return {
          id: userData.id,
          email: userData.email,
          password: userData.password,
          firstName: userData.firstName,
          lastName: userData.lastName,
          createdAt: userData.createdAt,
        };
      }

      return null;
    } catch (error) {
      console.error("User login failed:", error);
      throw error;
    }
  }

  async getUserByEmail(email: string): Promise<User | null> {
    if (!this.db) {
      throw new Error("Database not initialized");
    }

    try {
      const result = await this.db.executeSql(
        "SELECT * FROM users WHERE email = ?",
        [email]
      );

      if (result[0].rows.length > 0) {
        const userData = result[0].rows.item(0);
        return {
          id: userData.id,
          email: userData.email,
          password: userData.password,
          firstName: userData.firstName,
          lastName: userData.lastName,
          createdAt: userData.createdAt,
        };
      }

      return null;
    } catch (error) {
      console.error("Get user by email failed:", error);
      throw error;
    }
  }

  async closeDatabase(): Promise<void> {
    if (this.db) {
      await this.db.close();
      this.db = null;
    }
  }
}

export default new DatabaseService();