const { Sequelize, DataTypes } = require("sequelize");

const sequelize = new Sequelize("Demo", "postgres", "password", {
  host: "localhost",
  dialect: "postgres",
});

const Student = sequelize.define(
  "Student",
  {
    Id: {
      type: DataTypes.INTEGER,
      primaryKey: true,
      autoIncrement: true,
    },
    Name: {
      type: DataTypes.STRING,
      allowNull: false,
    },
    Age: {
      type: DataTypes.INTEGER,
      allowNull: false,
    },
    Email: {
      type: DataTypes.STRING,
      allowNull: false,
    },
    Phone: {
      type: DataTypes.BIGINT,
      allowNull: true,
    },
  },
  {
    tableName: "student_data",
    timestamps: false,
  }
);

const connectDatabase = async () => {
  try {
    await sequelize.authenticate();
    console.log("Connected to the PostgreSQL database successfully.");
    await Student.sync()
  } catch (error) {
    console.error("Unable to connect to the database:", error);
  }
};
connectDatabase();

const getUsers = async (req, res) => {
  try {
    const students = await Student.findAll();
    res.status(200).json(students);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
};

const getUserById = async (req, res) => {
  try {
    const student = await Student.findByPk(req.params.id);
    if (student) {
      res.status(200).json(student);
    } else {
      res.status(404).json({ error: "Student not found" });
    }
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
};

const createUser = async (req, res) => {
  try {
    const { Name, Age, Email } = req.body;
    const newStudent = await Student.create({ Name, Age, Email });
    res.status(201).json({ message: `User added with ID: ${newStudent.Id}` });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
};

const updateUser = async (req, res) => {
  try {
    const { Name, Age, Email } = req.body;
    const [updated] = await Student.update(
      { Name, Age, Email },
      { where: { Id: req.params.id } }
    );
    if (updated) {
      res.status(200).json({ message: `User modified with ID: ${req.params.id}` });
    } else {
      res.status(404).json({ error: "Student not found" });
    }
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
};

const deleteUser = async (req, res) => {
  try {
    const deleted = await Student.destroy({ where: { Id: req.params.id } });
    if (deleted) {
      res.status(200).json({ message: "Data deleted successfully." });
    } else {
      res.status(404).json({ error: "Student not found" });
    }
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
};

module.exports = {
  getUsers,
  getUserById,
  createUser,
  updateUser,
  deleteUser,
};