<?php

/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4 foldmethod=marker: */

class DatabaseMySQL {

    protected $link;
    private $hostname;
    private $username;
    private $password;
    private $database;
    private $onInit = array();
    private $queries = array();
    public $debug = true;

    // {{{ __construct()

    public function __construct($hostname, $username, $password, $database = null, array $onInit = array())
    {
        /** store values for lazy connect */
        $this->hostname = $hostname;
        $this->username = $username;
        $this->password = $password;
        $this->database = $database;
        $this->onInit = $onInit;
    }

    // }}}
    // {{{ lazyConnect()

    private function lazyConnect()
    {
        /** use stored values to connect */
        $this->connect(
            $this->hostname
          , $this->username
          , $this->password
          , $this->database
        );
        return $this;
    }

    // }}}
    // {{{ connect()

    public function connect($hostname, $username, $password, $database = null)
    {
        $mysqli = @new mysqli($hostname, $username, $password, $database);
        if (mysqli_connect_errno()) {
            throw new DatabaseException(
                'Could not connect to database on: ' . $hostname . PHP_EOL
              . 'Server returned: ' . mysqli_connect_error() . ' (Errno. ' . mysqli_connect_errno() . ')'
            );
        }
        $this->link = $mysqli;
        /** execute init statements if any */
        if (count($this->onInit)) {
            foreach ($this->onInit as $statement) {
                $this->doExec($statement);
            }
        }
        return $this;
    }

    // }}}
    // {{{ checkLink()

    public function checkLink()
    {
        if (is_null($this->link)) {
            return false;
        }
        return true;
    }

    // }}}
    // {{{ selectDatabase()

    public function selectDatabase($database)
    {
        if ($this->checkLink() === false) {
            $this->lazyConnect();
        }
        if ($this->link->select_db($database) === false) {
            throw new DatabaseException(
                'Could not select database: ' . $database . PHP_EOL
              . 'Server returned: ' . $this->link->error . ' (Errno. ' . $this->link->errno . ')'
            );
        }
        $this->database = $database;
        return $this;
    }

    // }}}
    // {{{ getResult()

    private function getResult($statement, $database = null)
    {
        /** check if we have no link */
        if ($this->checkLink() === false) {
            /** lazy connect */
            $this->lazyConnect();
        }
        /** check if we are switching database */
        if (!is_null($database)) {
            /** store name of old one and switch to new */
            $old = $this->database;
            $this->selectDatabase($database);
        }
        /** check if we debug mode is on */
        if ($this->debug === true) {
            /** get result set within timers */
            $start  = microtime(true);
            $result = $this->link->query($statement);
            $end    = microtime(true);
            /** add to queries array */
            $this->queries[] = array(
                $this->clean($statement)
              , sprintf('%.8F', $end - $start)
            );
        /** if not, just get the result set */
        } else {
            $result = $this->link->query($statement);
        }
        /** switch back to old database if applicable */
        if (isset($old)) {
            $this->selectDatabase($old);
        }
        /** if result is boolean false then query failed */
        if ($result === false) {
            throw new DatabaseException(
                'Invalid query: ' . $statement . PHP_EOL
              . 'Server returned: ' . $this->link->error . ' (Errno. ' . $this->link->errno . ')'
            );
        }
        /** return result set */
        return $result;
    }

    // }}}
    // {{{ doSelect()

    public function doSelect($statement, $database = null)
    {
        return $this->getResult($statement, $database);
    }

    // }}}
    // {{{ doInsert()

    public function doInsert($statement, $database = null)
    {
        $this->getResult($statement, $database);
        return $this->link->insert_id;
    }

    // }}}
    // {{{ doAlter()

    public function doAlter($statement, $database = null)
    {
        $this->getResult($statement, $database);
        return $this->link->affected_rows;
    }

    // }}}
    // {{{ doExec()

    public function doExec($statement, $database = null)
    {
        $this->getResult($statement, $database);
        return $this;
    }

    // }}}
    // {{{ escape()

    public function escape($string)
    {
        /** check if we have no link */
        if ($this->checkLink() === false) {
            /** lazy connect */
            $this->lazyConnect();
        }
        /** return the value properly escaped */
        return $this->link->real_escape_string($string);
    }

    // }}}
    // {{{ clean()

    public function clean($string)
    {
        /** strip all linebreaks and tabs, replace with spaces */
        $string = preg_replace('/[\r|\n|\t]/m', ' ', $string);
        /** strip all excess whitespace */
        $string = preg_replace('/ +/m', ' ', $string);
        /** return string */
        return trim($string);
    }

    // }}}
    // {{{ getQueries()

    public function getQueries()
    {
        return $this->queries;
    }

    // }}}
}