<?php
///<reference path="Database/PDOStatement.php" />
require_once "Database/PDOStatement.php";

/**
 * Класс оболочка для PDO для замены Creole 
 */
class Database/*<Database_PDOStatement>*/ extends PDO
{

    public $dsn;
    public function __construct($dsn, $username = null, $password = null)
    {
        parent::__construct($dsn, $username, $password);
        $this->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        $this->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
        $this->setAttribute(PDO::ATTR_STATEMENT_CLASS, array('Database_PDOStatement', array()));
    }
    
    function prepare($sql, $args = []) {
        $result = parent::prepare($sql, $args);
        return $result;
    }

    public function getDSN()
    {
        return $this->dsn;
    }
    public function isPostgres(){
        return ($this->dsn["phptype"] == "pgsql");
    }
    /**
     * Создает соединение с базой данных 
     */
    static function getConnection(array $dsn)
    {

        if ($dsn['phptype'] == 'pgsql' || $dsn['phptype'] == 'mysql') {            
            $port = (isset($dsn['port'])) ? "port={$dsn['port']};" : "";            
            $connection/*: Database*/ = new static("{$dsn['phptype']}:host={$dsn['hostspec']}; $port dbname={$dsn['database']}", $dsn['username'], $dsn['password']);
            if ($dsn['phptype'] == 'pgsql') {
                $connection->query('SET client_encoding="UTF-8"');
            }
            
            if (isset($dsn['schema'])) {
                $connection->query('SET search_path TO ' . $dsn['schema']);
            }
        }
        if ($dsn['phptype'] == 'sqlite') {
            $connection/*: Database*/ = new static("{$dsn['phptype']}:{$dsn['database']}");
            $connection->setAttribute(PDO::ATTR_TIMEOUT, 5);
            $mode = defined('SQLITE_JOURNAL_MODE') ? SQLITE_JOURNAL_MODE : 'WAL'; 
            $connection->query("PRAGMA journal_mode=$mode");

            if(!function_exists('sqliteLower')){
                function sqliteLower($str) {
                    return mb_strtolower($str, 'UTF-8');
                }
                $connection->sqliteCreateFunction('LOWER', 'sqliteLower', 1);
            }
        }
        $connection->dsn = $dsn;
        return $connection;
    }

    public function executeQuery($query, $values=null)
    {
        $stmt/*: Database_PDOStatement*/ = $this->prepare($query);

        $stmt->execute($values);
        $stmt->cache = $stmt->fetchAll(PDO::FETCH_ASSOC);
        return $stmt;
    }    

    public function prepareStatement($query)
    {
        return new Database_Statement($query, $this);
    }

    // Для совместимости со старым представлением баз данных CIS
    /**
     * Извлекает из базы все элементы по запросу 
     */
    public function fetchAllArray($query, $values = null)
    {
        $sth/*: Database_PDOStatement*/ = $this->prepare($query);
        $prep = $this->prepareValues($values);
        $sth->execute($prep);
        return $sth->fetchAll(PDO::FETCH_ASSOC);
    }

    /**
     * Извлекает из базы первый элемент по запросу 
     */
    public function fetchOneArray($query, $values = null) 
    {
        $sth/*: Database_PDOStatement*/ = $this->prepare($query);
        $prep = $this->prepareValues($values);
        $sth->execute($prep);
        return $sth->fetch(PDO::FETCH_ASSOC);
    }

    private static function assignQuote($x, $y) 
    {
        return $x . "=" . $this->quote($y);
    }

    private function prepareValues($values)
    {
        if (!$values) { 
            return null;
        }
        $pg = $this->isPostgres();
        $prep = array();
        foreach ($values as $key => $value) {
            $result = null;
            if(is_bool($value)) {
                if ($pg) {
                    $result = $value ? 'true' : 'false';
                } else {
                    $result = $value ? 1 : 0;
                }
            } else {
                $result = $value;
            }
            $prep[":" . $key] = $result;
        }
        return $prep;
    }
    /**
     * Создает INSERT запрос 
     */
    function insertQuery($table, array $values, $return_id = false, $index = null)
    {
        $prep = $this->prepareValues($values);

        $sql = "INSERT INTO $table (" . implode(",", array_keys($values)) 
        . ") VALUES (" . implode(",", array_keys($prep)). ")";
        if ($return_id) {
            if ($this->isPostgres()){
                $sql = $sql." RETURNING $index";
            }
        }
        $stmt = $this->prepare($sql);
        $stmt->setFetchMode(PDO::FETCH_ASSOC);
        $stmt->execute($prep);
        $result = $stmt->fetch();
        if ($return_id) {
            if ($this->isPostgres()) {
                return $result[$index];
            } else {
                $result = $this->fetchOneArray("SELECT $index AS lastid FROM $table WHERE OID = last_insert_rowid()");
                return $result['lastid'];
            }
        }
    }

    /**
     * Создает UPDATE запрос 
     */
    function updateQuery($table, array $values, $cond)
    {
        $prep = $this->prepareValues($values);
        $sql = "UPDATE $table SET " . implode(",", 
            array_map(function($k,$v){return $k."=".$v;}, array_keys($values), array_keys($prep))) . " WHERE $cond";

        $stmt = $this->prepare($sql);
        $stmt->setFetchMode(PDO::FETCH_ASSOC);
        $stmt->execute($prep);
    }

    function getIdGenerator() {
        return new Database_IdGenerator($this);
    }

    /**
     * Замечание: Только для Postgres SQL
     * @param string $seq Имя последовательности для ключа таблицы 
     * @return int Идентефикатор следующей записи 
     */
    function getNextId($seq) {
        $result = $this->fetchOneArray("SELECT nextval('$seq')");
        return $result['nextval'];
    }

    function close()
    {
        return null;
    }
}