<?php
require_once("Database.php");
require_once("exceptions.php");

class User
{
    private $username;
    private $email;
    private $active;
    private $confirmation_string;
    private $symbols;

    function __construct($username, $password)
    {
        $this->symbols = Array();

        if($this->login($username, $password))
        {
            $this->load_user();
        }
        else
        {
            throw new LoginFailureException("Bad username or password");
        }
    }

    private function login($username, $password)
    {
        global $database;

        $success = FALSE;

        $query = "SELECT username, email, password, active, confirmation_string FROM profiles WHERE username = ?";

        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("s", $username);
            $statement->execute();
            $statement->bind_result($username, $email, $password_hash, $active, $confirmation_string);
            $statement->fetch();

            $salt = substr($password_hash, 0, 5);
            $hash = substr($password_hash, -40);
            if($hash == sha1($salt . $password))
            {
                $this->username = $username;
                $this->email = $email;
                $this->active = $active;
                $this->confirmation_string = $confirmation_string;
                $success = TRUE;
            }

            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when attempting to log in");

        }

        return $success;
    }

    private function load_user()
    {
        global $database;

        $query = "SELECT tracked_stocks.symbol FROM profiles INNER JOIN tracked_stocks ON profiles.id = tracked_stocks.profile_id WHERE profiles.username = ?";

        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("s", $this->username);
            $statement->execute();
            $statement->bind_result($symbol);
            while($statement->fetch())
            {
                $this->symbols[] = $symbol;
            }
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when loading user details");
        }
    }

    public function get_username()
    {
        return $this->username;
    }

    public function get_email()
    {
        return $this->email;
    }

    public function is_active()
    {
        return $this->active;
    }

    public static function check_confirmation_string($confirmation_string)
    {
        global $database;

        $query = "SELECT username, confirmation_string FROM profiles WHERE confirmation_string = ?";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("s", $confirmation_string);
            $statement->execute();
            $statement->bind_result($username, $stored_confirmation);
            $statement->fetch();
            $statement->close();
        }

        if($stored_confirmation == $confirmation_string)
        {
            User::set_active($username, TRUE);
            return TRUE;
        }
        else
        {
            return FALSE;
        }
    }

    public function get_symbols()
    {
        return $this->symbols;
    }

    public function set_password($password)
    {
        global $database;

        $salt = rand(10000, 99999);
        $hashed_pass = $salt . sha1($salt . $password);

        $query = "UPDATE profiles SET password = ? WHERE username = ?";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("ss", $hashed_pass, $this->username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when setting password");
        }
    }

    public function set_email($email)
    {
        global $database;

        $query = "UPDATE profiles SET email = ? WHERE username = ?";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("is", $email, $this->username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when setting email");
        }
        $this->email = $email;
    }

    private static function set_active($username, $active)
    {
        global $database;


        $query = "UPDATE profiles SET active = ? WHERE username = ?";
        if ($statement = $database->connection->prepare($query))
        {
            $active = $active ? 1 : 0;
            $statement->bind_param("is", $active, $username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when setting profile activation");
        }
    }

    public static function new_confirmation_string($username)
    {
        global $database;

        $confirmation_string = md5(rand());
        $query = "UPDATE profiles SET confirmation_string = ? WHERE username = ?";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("is", $confirmation_string, $username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when creating a new confirmation string");
        }
        return $confirmation_string;
    }

    public function add_symbol($symbol)
    {
        global $database;

        if(in_array($symbol, $this->symbols))
        {
            throw new DuplicateSymbolException("Symbol '" . $symbol . "' already exists for user '" . $this->username . "'");
        }

        $query = "INSERT INTO tracked_stocks VALUES (null, ?, (SELECT id FROM profiles WHERE username = ?) ) ;";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("ss", $symbol, $this->username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when adding symbol");
        }

        $this->symbols[] = $symbol;

    }

    public function remove_symbol($symbol)
    {
        global $database;

        if(!in_array($symbol, $this->symbols))
        {
            throw new SymbolNotFoundException("Symbol '" . $symbol . "' does not exist for user '" . $this->username . "'");
        }

        $query = "DELETE FROM tracked_stocks WHERE symbol = ? AND profile_id = (SELECT id FROM profiles WHERE username = ?);";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("ss", $symbol, $this->username);
            $statement->execute();
            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when removing symbol");
        }

        $this->symbols = array_filter($this->symbols, function($current) use ($symbol) { return $current != $symbol; });
    }

    public static function create_profile($username, $password, $email)
    {
        global $database;

        $salt = rand(10000, 99999);
        $hashed_pass = $salt . sha1($salt . $password);

        $active = 0;
        $confirmation_string = md5(rand());

        $query = "INSERT INTO profiles VALUES ( null, ?, ?, ?, ?, ? );";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("sssis", $username, $hashed_pass, $email, $active, $confirmation_string);
            if(!$statement->execute())
            {
                if($statement->errno == 1062)
                {
                    throw new DuplicateUserException("Username '" . $username . "' already exists");
                }
                else
                {
                    throw new QueryException("Error " . $statement->errno . ": " . $statement->error);
                }
                $statement->close();
            }
        }
        else
        {
            throw new QueryException("Malformed query when creating profile");
        }

        return $confirmation_string;
    }

    public static function delete_profile($username)
    {
        global $database;

        $query = "DELETE FROM profiles WHERE profiles.username = ?;";
        if ($statement = $database->connection->prepare($query))
        {
            $statement->bind_param("s", $username);
            $statement->execute();
            if($statement->errno == 0 && $statement->affected_rows == 0)
            {
                throw new UserNotFoundException("User not found when attempting to delete profile");
            }

            $statement->close();
        }
        else
        {
            throw new QueryException("Malformed query when deleting profile");
        }
    }

}