<?php

/**
 * @author     Ben Borowski <ben.borowski@typeoneerror.com>
 * @copyright  Copyright (c) 2008-9 TypeOneError Studios (http://www.typeoneerror.com)
 * @license    MIT ~ http://www.opensource.org/licenses/mit-license.php
 * @version    $Id$
 * @link       http://typeoneerror.com/asra
 * @category   Asra
 * @package    Db
 */

/**
 * MySQL connection and query handlers. Provides some
 * abstraction for querying a mysql database.
 *
 * @todo Make charset accessible to code and ini
 *
 * @author     Ben Borowski <ben.borowski@typeoneerror.com>
 * @copyright  Copyright (c) 2008-9 TypeOneError Studios (http://www.typeoneerror.com)
 * @license    MIT ~ http://www.opensource.org/licenses/mit-license.php
 * @link       http://typeoneerror.com/asra
 * @category   Asra
 * @package    Db
 */
class Asra_Db_MySQL
{
    //---------------------------------------
    // PROTECTED VARIABLES
    //---------------------------------------

    /**
     * Connect by default
     *
     * @var bool
     */
    protected $_autoConnect = true;

    /**
     * Which character set to use to connect
     *
     * @var string
     */
    protected $_charset = 'utf8';

    /**
     * MySQL host
     *
     * @var string
     */
    protected $_host = 'localhost';

    /**
     * Link to connected database
     *
     * @var resource
     */
    protected $_link = null;

    /**
     * MySQL password
     *
     * @var string
     */
    protected $_pass = 'root';

    /**
     * MySQL username
     *
     * @var string
     */
    protected $_user = 'root';

    //---------------------------------------
    // PUBLIC VARIABLES
    //---------------------------------------

    /**
     * Connected to mysql
     *
     * @var bool
     */
    public $connected = false;

    /**
     * Database name
     *
     * @var string
     */
    public $db = null;

    /**
     * Last query run
     *
     * @var string
     */
    public $last = null;

    /**
     * Class has connected and database has been selected
     *
     * @var bool
     */
    public $ready = false;

    //---------------------------------------
    // CONSTRUCTOR
    //---------------------------------------

    /**
     * Create a MySQL object.
     *
     * @param array $config      Database config.
     * @param bool $autoConnect  Automatically open link to mysql.
     * @return Asra_Db_Mysql     Reference for fluent interface.
     */
    public function __construct($config = null, $autoConnect = true)
    {
        $this->_autoConnect = $autoConnect;

        if ($config != null)
        {
            $this->config(
                $config->connection['database.params.host'],
                $config->connection['database.params.username'],
                $config->connection['database.params.password'],
                $config->connection['database.params.dbname']
            );

            if ($autoConnect)
            {
                $this->_connect();
            }
        }
        return $this;
    }

    //---------------------------------------
    // METHODS
    //---------------------------------------

    /**
     * Closes the mysql connected explicitly.
     *
     * @return bool
     */
    public function close()
    {
        $this->connected = false;
        return mysql_close($this->_link);
    }

    /**
     * Sets the connection strings.
     *
     * @return Asra_Db_Mysql
     */
    public function config($host, $user, $pass, $db)
    {
        $this->_host = $host;
        $this->_user = $user;
        $this->_pass = $pass;
        $this->db    = $db;

        return $this;
    }

    /**
     * Connects to the database.
     *
     * @return Asra_Db_Mysql
     */
    public function connect()
    {
        $this->_connect();
        return $this;
    }

    /**
     * Connects to mysql database.
     *
     * @return resource or boolean false on failure.
     */
    protected function _connect()
    {
        if (!$this->connected)
        {
            $this->_link = @mysql_connect($this->_host, $this->_user, $this->_pass);
            @mysql_set_charset($this->_charset, $this->_link);
        }

        if (!$this->_link)
        {
            $this->_error("Could not connect to `" . $this->_host . "` as `" . $this->_user . "`");
        }
        else
        {
            $this->connected = true;
            if (!$this->ready)
            {
                if ($this->selectdb())
                {
                    $this->ready = true;
                }
            }
        }

        return $this->_link;
    }

    /**
     * Document an error and then die.
     *
     * @return void
     */
    protected function _error($text = null)
    {
        //trigger_error($text, E_USER_ERROR);
        //exit;
        require_once "Asra/Db/Exception.php";
        throw new Asra_Db_Exception($text);
    }

    /**
     * Checks whether a table exists in a database.
     *
     * @param string $table  Name of table.
     * @return bool          True if table exists.
     */
    public function exists($table)
    {
        if ($this->ready)
        {
            $tables = array();
            $query = @mysql_query("SHOW TABLES");
            while ($result = @mysql_fetch_array($query))
            {
                $tables[] = $result[0];
            }
            @mysql_free_result($query);
            if (in_array($table, $tables)) return true;
            else return false;
        }
        else
        {
            return false;
        }
    }

    /**
     * Get the database name.
     *
     * @return string  The database name.
     */
    public function getDb()
    {
        return $this->db;
    }

    /**
     * Get the hostname.
     *
     * @return string  The hostname.
     */
    public function getHost()
    {
        return $this->_host;
    }

    /**
     * Get user name.
     *
     * @return string  The user name.
     */
    public function getUser()
    {
        return $this->_user;
    }

    /**
     * Runs a query and returns the result as an object array
     *
     * @param string $query
     * @return array of objects or false if no results
     */
    public function obj($query)
    {
        return $this->query($query, true);
    }

    /**
     * Run a query on the MySQL connection.
     *
     * @param string $query  Query to run.
     * @return array or false if no results.
     */
    public function query($query, $object = false)
    {
        $this->last = $query;
        $result = mysql_query($query);
        if (!$result)
        {
            $this->_error(mysql_error());
        }
        if (mysql_num_rows($result))
        {
            $rows = array();
            $func = $object ? 'mysql_fetch_object' : 'mysql_fetch_assoc';
            while ($row = $func($result))
            {
                $rows[] = $row;
            }
            return $rows;
        }
        else
        {
            return false;
        }
    }

    /**
     * The same as query() but returns a single row. Thus no wrapper array.
     *
     * @param string $query  The query to run.
     * @return array         A single array row result.
     */
    public function row($query)
    {
        // -- add an auto LIMIT 1 to it
        if (stripos($query, 'limit') === false) $query .= ' LIMIT 1';
        // -- run the query like normal
        $result = $this->query($query);
        // -- return an empty array if no results
        if ($result === false) return false;
        else return $result[0];
    }

    /**
     * Run query and return effected rows if asked.
     *
     * @param string $query   Query to run.
     * @param bool $effected  Return effected rows.
     * @return bool or int if effected is true.
     */
    public function run($query, $effected = false)
    {
        $this->last = $query;
        $result = mysql_query($query);
        if ($result)
        {
            if ($effected) return mysql_affected_rows();
            return true;
        }
        else
        {
            return false;
        }
    }

    /**
     * Search for rows based on a simple condition.
     *
     * @param string $table   Database table to search.
     * @param string $search  Search params for WHERE.
     * @param string $fields  Fields to select in the query.
     * @return array or false if no results.
     */
    public function search($table, $search = '', $fields = ' * ')
    {
        $query = "SELECT ";
        if (notnull($fields))
        {
            $query .= $fields;
        }
        else
        {
            $query .= " * ";
        }
        $query .= " FROM " . $table;
        if (notnull($search))
        {
            $query .= " WHERE " . $search;
        }
        $this->last = $query;
        $result = mysql_query($query);
        if (!$result)
        {
            $this->_error(mysql_error());
        }
        if (mysql_num_rows($result))
        {
            $rows = array();
            while ($row = mysql_fetch_assoc($result))
            {
                $rows[] = $row;
            }
            return $rows;
        }
        else
        {
            return false;
        }
    }

    /**
     * Select a database.
     *
     * @param string $db  Name of database
     * @return bool       True if database could be selected.
     */
    public function selectdb($db = null)
    {
        if (is_null($db)) $db = $this->db;
        return (mysql_select_db($db));
    }

}