Database API

<?php

    // Define include flag
    $INCLUDE_DATABASE = true;

    // Include required files
    if(!isset($INCLUDE_CONFIG)){
        include "../config.php";
    }
    if(!isset($INCLUDE_UTILS)){
        include "utils.php";
    }
    if(!isset($INCLUDE_SQL)){
        include "sql.php";
    }

    // Class definition
    $db = new Database();

    class Database {

        private $host = "";
        private $user = "";
        private $pass = "";
        private $name = "";

        public $connection;

        /*
         * Load configs into class
         *
         */
        function __construct(){
            global $config;
            $this->host = $config->database->host;
            $this->name = $config->database->name;
            $this->user = $config->database->user;
            $this->pass = $config->database->pass;
        }

        /*
         * Executes a query and returns the result
         *
         * @param $query sql query
         *
         */
        public function query($query){
            $this->open();
            $this->select_db($this->name);
            $res = mysqli_query($this->connection, $query);
            $this->close();

            return $res;
        }

        /*
         * Establishes a connection to the database
         *
         */
        public function open(){
            $this->connection = mysqli_connect($this->host,$this->user,$this->pass) or die("Connection failed");
        }

        /*
         * Slects a database
         *
         */
        public function select_db($dbname){
            mysqli_select_db($this->connection,$dbname);
        }

        /*
         * Closes the database connection
         *
         */
        public function close(){
            mysqli_close($this->connection);
        }

        /*
         * Inserts a new row into a table if the user have permission to do so
         *
         * @param  $keys            keys to be inserted
         * @param  $values          the corresponding values
         * @param  $table           the table to be inserted
         * @param  $permissionLevel min required permission level
         * @return success
         *
         */
        public function insert($keys, $values, $table, $permissionLevel){
            global $config, $utils;
            $pLevel = $utils->getSessionVariable("permissionLevel");

            if($utils->checkPermissions($pLevel, $permissionLevel)){
                $query = "INSERT INTO ${table} ${keys} VALUES ${values}";

                $res = $this->query($query);

                return $res;
            }

            return $config->permission->denied;
        }

        /*
         * Fetches data from a table
         *
         * @param  $keys            keys to be fetched
         * @param  $table           the table to be fetched from
         * @param  $join            tables to join
         * @param  $where           fetch condition
         * @param  $limit           limit the amount of results
         * @param  $permissionLevel min required permission level
         * @return fetched data
         *
         */
        public function fetch($keys, $table, $join, $where, $limit, $permissionLevel){
            global $config, $utils;
            $pLevel = $utils->getSessionVariable("permissionLevel");

            if($utils->checkPermissions($pLevel, $permissionLevel)){
                $query = "SELECT ${keys} FROM ${table}";

                if($join){
                    $query .= $join;
                }
                if($where){
                    $query .= " WHERE " . $where;
                }
                if($limit){
                    $query .= $limit;
                }

                $res = $this->query($query);

                return $res;
            }

            return $config->permission->denied;
        }

        /*
         * Updates a row in table
         *
         * @param  $keyval          key-value-pairs to update
         * @param  $table           the table to update
         * @param  $where           update condition
         * @param  $permissionLevel min required permission level
         * @return success
         *
         */
        public function update($keyval, $table, $where, $permissionLevel){
            global $config, $utils;
            $pLevel = $utils->getSessionVariable("permissionLevel");

            if($utils->checkPermissions($pLevel, $permissionLevel) && $where){
                $query = "UPDATE ${table} SET ${keyval} WHERE ${where}";

                $res = $this->query($query);

                return $res;
            }

            return $config->permission->denied;
        }

        /*
         * Returns a value in a mysqli result
         *
         * @param  $res mysql result
         * @return data of the first column
         *
         */
        public function getValue($result, $key){
            if($result && mysqli_num_rows($result) !== 0){
                return mysqli_fetch_assoc($result)[$key];
            }

            return FALSE;
        }

        /*
         * Returns an array of assoc arrays
         *
         * @param  $res mysql result
         * @return array of assoc arrays
         *
         */
        public function getAssoc($result){
            if($result && mysqli_num_rows($result) !== 0){
                $entrys = array();
                $entry = NULL;

                while($entry = mysqli_fetch_assoc($result)){
                    array_push($entrys, $entry);
                }

                return $entrys;
            }

            return array();
        }

        /*
         * Creates a unique id in the table
         *
         * @param  $table unique id in table
         * @return uid
         *
         */
        public function generateUID($table){
            global $config, $utils, $db;

            $id = $utils->generateID($config->id->length);

            $res = $db->fetch("uid", $table, "", "uid=${id}", 1, $config->permission->UNCONFIRMED);

            if($this->getValue($res, "uid")){
                return $this->generateUID($table);
            }

            return $id;
        }

    }
?>
<?php

    // Define include flag
    $INCLUDE_SQL = true;

    // Class definition
	$sql = new SQL();

	class SQL {

        /*
         * Variables into sql values string
         *
         * @param  variable parameter list (values)
         * @return sql values string
         *
         */
        public function values(){
            $value = "";
            $parameterList = func_get_args();

            for($i = 0; $i < count($parameterList); $i++){
                $value .= "'{$parameterList[$i]}'";

                if($i < count($parameterList) - 1){
                    $value .= ", ";
                }
            }
            return $this->clamp($value);
        }

        /*
         * Creates a key-value-pair
         *
         * @param $key
         * @param $value
         * @param $quotes bool value in quotes
         *
         */
        public function keyValue($key, $value, $quotes=FALSE){
            return $quotes ? " ${key}='${value}'" : " ${key}=${value}";
        }

        /*
         * Clamps string into brackets
         *
         * @param  $sql sql string
         * @return clamped string
         *
         */
		public function clamp($sql){
            return " (${sql})";
        }

        /*
         * Creates sql like statement
         *
         * @param $column
         * @param $query string to compare
         * @return sql like statement
         *
         */
        public function like($column, $query){
            return " ${column} LIKE '%${query}%'";
        }

        /*
         * Concatenates two conditions with an 'and'
         *
         * @param  $condition1
         * @param  $condition2
         * @return concat 'and' sql string
         *
         */
        public function logicalAnd($condition1, $condition2){
            return " ${condition1} AND ${condition2}";
        }

        /*
         * Concatenates two conditions with an 'or'
         *
         * @param  $condition1
         * @param  $condition2
         * @return concat 'or' sql string
         *
         */
        public function logicalOr($condition1, $condition2){
            return " ${condition1} OR ${condition2}";
        }

        /*
         * Creates sql inner join statement
         *
         * @param  $table     to join
         * @param  $condition
         * @return sql inner join statement
         *
         */
        public function innerJoin($table, $condition){
            return " INNER JOIN ${table} ON ${condition}";
        }

        /*
         * Creates sql limit statement with an max value cap
         *
         * @param  $limit
         * @return sql limit statement
         *
         */
        public function limit($limit){
            global $config;
            $limit = $limit <= $config->baseLimit ? $limit : $config->baseLimit;
            return " LIMIT ${limit}";
        }

	}

?>