```
<?php

class Member {
    /*
    * @Member class: This is the base account type and very other account type should inherit from this
    * @author: Al Nmeri
    * ==== @constructor ====
    * @param: a unique username to init user for db indexing.
    * @returns: attaches user info to properties
    **/
    public $name;
    public $pagename;
    public $can_comment;
    public $profile_pic;
    public $username;
    public $bio;
    public $account_type;

    public function __construct($name) {
        $this->name = str_replace('_', ' ', ucwords(strtolower($name)));
        $this->pagename = "http://site.com/". strtolower(str_replace('_', '.', $name)) . '/';
        $this->can_comment = true;
        $this->profile_pic = "http://site.com/user.png";
        $this->username = $name;
        $this->bio = "";
        $this->account_type = 'member';
        }

    /*
    * @param: PDO conn object
    * @returns: returns true on successful insert of all user properties into db
    **/
    public function activate (PDO $conn) {

    $active = $conn->prepare("INSERT INTO user_info (name, username, pagename, can_comment, profile_pic, bio, account_type) VALUES (:name, :username, :pagename, :can_comment, :profile_pic, :bio, :account_type)");

    $active->execute((array) $this);
    return true;
    }

    /*
    * @description: For settings page. To fetch all alterable user properties
    * @param: PDO conn object
    * @param: joiner: the variable that join the tables
    * @returns: returns an object containing current user properties for sitewide usage
    **/

    public static function fetch_me (PDO $conn, $joiner) {

        $prep = $conn->prepare("SELECT users.username, users.email, users.password, user_info.name, user_info.profile_pic, user_info.bio, user_info.pagename FROM users INNER JOIN user_info ON users.username=user_info.username WHERE users.username=?"); //ON is the joiner between the tables like WHERE is for values

        $prep->execute([filter_var($joiner, FILTER_SANITIZE_STRING)]);

        return $prep->fetch(PDO::FETCH_OBJ);
    }

    /*
    * @param: $old_pass: old password
    * @param: $new_pass: new password;
    * @param: $conn: PDO connection
    * @description: changes user password
    * @returns: false on wrong password or failure
    **/
    public static function change_password($old_pass, $new_pass, $conn) {
            $new_pass = password_hash($new_pass, PASSWORD_BCRYPT);
            $sess = $_SESSION['username'];

            if (password_verify($old_pass, SELF::fetch_me($conn, $sess)->password)) {
            $change_pass_query = $conn->prepare("UPDATE users SET password=? WHERE username=?")->execute([$new_pass, $sess]);
        }
        else return false;
    }

    /*
    * @param: $pass: user password
    * @param: $new_email: $email to change to
    * @param: $conn: PDO connection
    * @description: changes user email
    * @returns: false on wrong password or failure
    **/
    public static function change_email($pass, $new_email, $conn) {
        $sess = $_SESSION['username'];
        $new_email = filter_var($new_email, FILTER_SANITIZE_EMAIL);

        if (password_verify($pass, SELF::fetch_me($conn, $sess)->password)) {
            //test if email is already in use by someone else

            $email_in_use = $conn->prepare("SELECT COUNT(*) FROM users WHERE email=?")->execute([$new_email]);

            if ($email_in_use->fetchColumn() == "1") {
                return "<span style='color: red; padding-left:5%;' id='errorText'> sorry. email in use by another user </span>";
            }
            //else update db with new email

            else {
                $change_email_query = $conn->prepare("UPDATE users SET email=? WHERE username= ?")->execute([$new_pass, $sess]);
        }
    }
        else return "Changes not saved: wrong password.";
    }

    /*
    * @param: valid PDO connection
    * @param: Session variable
    * @description: updates user's last login
    * @return: null
    **/
    public static function set_last_login($conn, $sess) {

        $update = $conn->query("UPDATE users SET last_login=NOW() WHERE username=?")->execute([$sess]);
    }

    public function bio($bio, $conn) {
        $sess = $_SESSION['username'];

        $update = $conn->prepare("UPDATE user_info SET bio=? WHERE username=?")->execute([htmlspecialchars($bio), $sess]);
    }

    /*
    * @function: A one time function to check if user has changed default display picture and updates db if so
    * @param: valid PDO connection
    **/
    public static function change_picture($conn){
        $sess = $_SESSION['username'];

        // Check if user has previously uploaded profile picture
        if (SELF::fetch_me($conn, $sess)->profile_pic == "../user.png") {
            $new_image_link = $_SERVER["DOCUMENT_ROOT"].'/a/profile_images/'. SELF::fetch_me($conn, $sess)->username. '.png';

            $dp = $conn->prepare("UPDATE user_info SET profile_pic=?")->execute([$new_image_link]);
        }
    }

    /*@function: In case of upgrade, use overloading to add new features **/
    public function __set ($name, $method){
        return $this->name = $method;
    }
}

?>
```