<?php

class database {

	var $host;
	var $user;
	var $password;
	var $database;
	var $result;
	var $link;

	function database($host, $user, $password, $database) {

		$this->host = $host;
		$this->user = $user;
		$this->password = $password;
		$this->database = $database;

	}

	function connect() {

		if (!$this->link) {

			$this->link = @mysql_connect($this->host, $this->user, $this->password, true);
			if (!$this->link) {
				$this->error('A connection could not be established with the database - ' . mysql_error(), true);
			}

			if (!@mysql_select_db($this->database, $this->link)) {
				$this->error('Selecting the database failed', true);
			}

			if ($GLOBALS['pageCharset'] == 'ISO-8859-1') {
				$charset = 'latin1';
			} else if ($GLOBALS['pageCharset'] == 'UTF-8') {
				$charset = 'utf8';
			} else {
				$charset = NULL;
			}

			if ($charset !== NULL) {
				if (function_exists('mysql_set_charset')) {
				 	mysql_set_charset($charset, $this->link);
				} else {
					mysql_query('SET NAMES ' . $charset);
				}
			}

		}

	}

	function error($query = 'N/A', $useQueryAsError = false) {

		if ($this->link) {
			$extra = mysql_errno($this->link) . ': ' . mysql_error($this->link);
		} else if (mysql_errno() != 0) {
			$extra = mysql_errno() . ': ' . mysql_error() . ' (no link)';
		} else {
			$extra = '';
		}

		if (function_exists('exitWithError') && $GLOBALS['dbErrorThrown'] == false) {
			$GLOBALS['dbErrorThrown'] = true;
			exitWithError('An error has occurred with the database', $query . "\n\n" . $extra);
		} else {
			header('HTTP/1.0 500 Internal Server Error');
			exit('<p>I have an error: <br />' . htmlentities($useQueryAsError ? $query : $extra) . '</p>');
		}

	}

	function escape($val) {

		$this->connect();

		if (function_exists('mysql_real_escape_string')) {
			return mysql_real_escape_string($val, $this->link);

		} else if (function_exists('mysql_escape_string')) {
			return mysql_escape_string($val);

		} else {
			return addslashes($val);
		}

	}

	function escapeString($val) {
		return '"' . $this->escape($val) . '"';
	}

	function escapeLike($val) {
		$val = $this->escape($val);
		$val = str_replace('_', '\_', $val);
		$val = str_replace('%', '\%', $val);
		return $val;
	}

	function escapeField($field) {
		$sqlField = '`' . str_replace('`', '', $field) . '`'; // Back tick is an illegal character
		$sqlField = str_replace('.', '`.`', $sqlField); // Allow table definition
		return $sqlField;
	}

	function query($query, $runDebug = true) {
		$this->connect();
		if ($runDebug && function_exists('debugDatabase')) {
			$this->result = debugDatabase($this, $query);
		} else {
			$this->result = mysql_query($query, $this->link) or $this->error($query);
		}
		return $this->result;
	}

	function numRows($result = null) {
		if ($result === null) $result = $this->result;
		return mysql_num_rows($result);
	}

	function fetchAssoc($result = null) {
		if ($result === null) $result = $this->result;
		return mysql_fetch_assoc($result);
	}

	function fetchArray($result = null) {
		if ($result === null) $result = $this->result;
		return mysql_fetch_array($result);
	}

	function result($row, $col, $result = null) {
		if ($result === null) $result = $this->result;
		return mysql_result($result, $row, $col);
	}

	function insertId() {
		return mysql_insert_id($this->link);
	}

	function affectedRows() {
		return mysql_affected_rows($this->link);
	}

	function enumValues($sqlTable, $field) {
		$this->query('SHOW COLUMNS FROM ' . $sqlTable . ' LIKE "' . $this->escape($field) . '"');
		if ($row = $this->fetchAssoc()) {
			return explode("','", preg_replace("/(enum|set)\('(.+?)'\)/", '\2', $row['Type']));
		} else {
			$this->error('Could not return enum values for field "' . $field . '"');
		}
	}

	function insert($sqlTable, $values, $onDuplicate = NULL) {

		$sqlFields = implode(', ', array_map(array($this, 'escapeField'), array_keys($values)));
		$sqlValues = implode(', ', array_map(array($this, 'escapeString'), $values));

		if ($onDuplicate === NULL) {

			$this->result = $this->query('INSERT INTO ' . $sqlTable . ' ('. $sqlFields . ') VALUES (' . $sqlValues . ')');

		} else if (!is_array($onDuplicate)) {

			$this->result = $this->query('INSERT INTO ' . $sqlTable . ' ('. $sqlFields . ') VALUES (' . $sqlValues . ') ON DUPLICATE KEY UPDATE ' . $onDuplicate);

		} else {

			$sqlSet = array();
			foreach ($onDuplicate as $fieldName => $fieldValue) {
				$sqlSet[] = $this->escapeField($fieldName) . ' = ' . $this->escapeString($fieldValue);
			}
			$sqlSet = implode(', ', $sqlSet);

			$this->result = $this->query('INSERT INTO ' . $sqlTable . ' ('. $sqlFields . ') VALUES (' . $sqlValues . ') ON DUPLICATE KEY UPDATE ' . $sqlSet);

		}

		return $this->result; // insertId or affectedRows

	}

	function update($sqlTable, $values, $sqlWhere) {

		$sqlSet = array();
		foreach ($values as $fieldName => $fieldValue) {
			$sqlSet[] = $this->escapeField($fieldName) . ' = ' . $this->escapeString($fieldValue);
		}
		$sqlSet = implode(', ', $sqlSet);

		$this->result = $this->query('UPDATE ' . $sqlTable . ' SET '. $sqlSet . ' WHERE ' . $sqlWhere);
		return $this->result; // affectedRows

	}

	function select($sqlTable, $fields, $sqlWhere, $limit = NULL) {

		if ($fields === 1) {
			$sqlFields = '1';
		} else if ($fields === NULL) {
			$sqlFields = '*';
		} else {
			$sqlFields = implode(', ', array_map(array($this, 'escapeField'), $fields));
		}

		$sqlLimit = ($limit === NULL ? '' : ' LIMIT ' . intval($limit));

		$this->result = $this->query('SELECT ' . $sqlFields . ' FROM ' . $sqlTable . ' WHERE ' . $sqlWhere . $sqlLimit);
		return $this->result; // numRows or fetchAssoc

	}

	function delete($sqlTable, $sqlWhere) {

		$this->result = $this->query('DELETE FROM ' . $sqlTable . ' WHERE ' . $sqlWhere);
		return $this->result; // affectedRows

	}

}

$GLOBALS['dbErrorThrown'] = false; // Common between multiple database class copies (=& not used)

?>