<?php
	/**
	 * Database
	 * Access databases using PDO and MySQL. Supports prepared statements.
	 *
	 * @package com.codeante.lib.base
	 * @author GIDIX
	 */

	class Database {
		private $db;
		public $lastQuery;

		/**
		 * This variable determines whether {@see Database} should handle errors
		 * or pass it on via an exception. If this is set to true, {@see Database} handles all errors.
		 *
		 * @var boolean
		 */
		public $handleError = false;

		/**
		 * @param string $host MySQL Host
		 * @param string $username MySQL Username
		 * @param string $password MySQL Password
		 * @param string $database MySQL Database
		 */
		public function __construct($host, $username, $password, $database) {
			$this->db = new PDO('mysql:host=' . $host . ';dbname=' . $database . ';charset=utf8', $username, $password);
			$this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
			$this->db->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
		}

		public function query($sql, array $args = null) {
			try {
				if (!is_null($args)) {
					$this->lastQuery = $this->db->prepare($sql);
					$this->lastQuery->execute($args);
				} else {
					$this->lastQuery = $this->db->query($sql);
				}

				return $this->lastQuery;
			} catch (PDOException $e) {
				if ($this->handleError) {
					$this->error($e->getMessage(), $sql, $e->getCode());
				} else {
					throw $e;
				}
			}
		}

		/**
		 * Prepare a statement and return it without executing.
		 *
		 * @param string $query Query to send.
		 */
		public function prepare($sql) {
			try {
				return $this->db->prepare($sql);
			} catch (PDOException $e) {
				if ($this->handleError) {
					$this->error($e->getMessage(), $sql, $e->getCode());
				} else {
					throw $e;
				}
			}
		}

		/**
		 * Fetch an object using its {@see PDOStatement} $stmt or the last query.
		 *
		 * @param PDOStatement $stmt (optional, null)
		 *
		 * @return stdClass
		 */
		public function fetchObject(PDOStatement $stmt = null) {
			if (!is_null($stmt)) {
				return $stmt->fetch(PDO::FETCH_OBJ);
			} else {
				return $this->lastQuery->fetch(PDO::FETCH_OBJ);
			}
		}

		public function fetch(PDOStatement $stmt = null, $fetch_style = FETCH_ASSOC) {
			if (!is_null($stmt)) {
				return $stmt->fetch(PDO::$fetch_style);
			} else {
				return $this->lastQuery->fetch(PDO::$fetch_style);
			}
		}

		/**
		 * Get the number of affected rows by $stmt or the last query.
		 *
		 * @param PDOStatement $stmt (optional, null)
		 *
		 * @return int
		 */
		public function numRows(PDOStatement $stmt = null) {
			if (!is_null($stmt)) {
				return $stmt->rowCount();
			} else {
				return $this->lastQuery->rowCount();
			}
		}

		/**
		 * Get the last inserted ID.
		 *
		 * @return int
		 */
		public function insertID() {
			return $this->db->lastInsertId();
		}

		/**
		 * Begin a transaction for committing and rollbacks.
		 */
		public function beginTransaction() {
			return $this->db->beginTransaction();
		}

		/**
		 * Commit a transaction.
		 */
		public function commit() {
			return $this->db->commit();
		}

		/**
		 * Rollback recent changes before they were commited.
		 */
		public function rollback() {
			return $this->db->rollBack();
		}

		public function errorInfo() {
			return $this->db->errorinfo();
		}

		protected function error($msg, $sql, $code) {
			Helpers::log(Helpers::LOG_ERROR, $msg . '<br /><br /><code class="important">' . $sql . '</code>');
		}

	}