<?php
       include ('condb.php');//connect to the database and check connection.

            // assign the variable.
        $email=mysqli_real_escape_string($conn, $_POST['email']);// accept the data with mysqli_real_escape_string() function.
        $password=mysqli_real_escape_string($conn,md5($_POST['password']));//save password with md5 function for security reason.

            // check the data with javascript alert function

        if ($email==''){// check yourname is empty or not by using javascript alert.
            echo "<script>alert('Enter your email')</script>";// give error message
            exit();// if data input field is empty stop here and don't go anyfuther.
        }

        $query="SELECT name
                FROM users
                WHERE email= '$email' AND password= '$password' ";// select 'name' data  from database call users where accept data email is same as the data in the database.


        $result=mysqli_query($conn,$query);// make connection and process query.
        $row=mysqli_fetch_array($result,MYSQLI_ASSOC);//mysqli_fetch_array ()fuction fetch a result row as numberic arry and associative array

            // check the userinput data

         if(count($row)>=1)//chech the result with if statement , if the data is there give error message or success ful login and show message.
        {
           echo $message = $row['name']." Login Sucessfully!!";//show name and give message
          header('Location:homepage.php');//link to the homepage.php


        }
        else
        {
            echo $message = "Invalid email or password!!";// other wise give error message.
            exit();
        }

        mysqli_close($conn);
?>