<?php

/*
    This file is a part of myTinyTodo.
    (C) Copyright 2019-2022 Max Pozdeev <maxpozdeev@gmail.com>
    Licensed under the GNU GPL version 2 or any later. See file COPYRIGHT for details.
*/

// ---------------------------------------------------------------------------- //
class DatabaseResult_Mysqli extends DatabaseResult_Abstract
{
    /** @var mysqli_result */
    protected $q;

    function __construct(mysqli $dbh, $query, $resultless = 0)
    {
        $this->q = $dbh->query($query); //throws mysqli_sql_exception
    }

    function fetchRow()
    {
        return $this->q->fetch_row();
    }

    function fetchAssoc()
    {
        return $this->q->fetch_assoc();
    }
}

// ---------------------------------------------------------------------------- //
class Database_Mysqli extends Database_Abstract
{
    /** @var mysqli */
    protected $dbh;
    protected $dbname;

    function __construct()
    {
        // enable throwing exceptions
        mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
    }

    function connect($params)
    {
        $host = $params['host'];
        $user = $params['user'];
        $pass = $params['password'];
        $db = $params['db'];
        $this->dbname = $db;
        $this->dbh = new mysqli($host, $user, $pass, $db); //throws mysqli_sql_exception
        return true;
    }

    function lastInsertId($name = null)
    {
        return $this->dbh->insert_id;
    }

    function sq($query, $p = NULL)
    {
        $q = $this->_dq($query, $p);

        $res = $q->fetchRow();
        if ($res === false || $res === null) return NULL;

        if (sizeof($res) > 1) return $res;
        else return $res[0];
    }

    function sqa($query, $p = NULL)
    {
        $q = $this->_dq($query, $p);

        $res = $q->fetchAssoc();
        if ($res === false || $res === null) return NULL;

        return $res;
    }

    function dq($query, $p = NULL) : DatabaseResult_Abstract
    {
        return $this->_dq($query, $p);
    }

    /*
        for resultless queries like INSERT,UPDATE,DELETE
    */
    function ex($query, $p = NULL)
    {
        $dbr = $this->_dq($query, $p, 1);
        return $this->affected();
    }

    private function _dq($query, $p = NULL, $resultless = 0) : DatabaseResult_Abstract
    {
        if (!isset($p)) $p = array();
        elseif (!is_array($p)) $p = array($p);

        $m = explode('?', $query);

        if (sizeof($p) > 0)
        {
            if (sizeof($m) < sizeof($p)+1) {
                throw new Exception("params to set MORE than query params");
            }
            if (sizeof($m) > sizeof($p)+1) {
                throw new Exception("params to set LESS than query params");
            }
            $query = "";
            for ($i=0; $i < sizeof($m)-1; $i++) {
                $query .= $m[$i]. (is_null($p[$i]) ? 'NULL' : $this->quote($p[$i]));
            }
            $query .= $m[$i];
        }
        $this->lastQuery = $query;
        return new DatabaseResult_Mysqli($this->dbh, $query, $resultless);
    }

    function affected()
    {
        return $this->dbh->affected_rows;
    }

    function quote($s)
    {
        return '\''. addslashes($s). '\'';
    }

    function quoteForLike($format, $s)
    {
        $s = str_replace(array('%','_'), array('\%','\_'), addslashes($s));
        return '\''. sprintf($format, $s). '\'';
    }

    function tableExists($table)
    {
        $r = $this->sq("SELECT 1 FROM information_schema.tables WHERE TABLE_SCHEMA = ? AND TABLE_NAME = ?",
                        array($this->dbname, $table) );
        if ($r === false || $r === null) return false;
        return true;
    }

    function tableFieldExists($table, $field): bool
    {
        $table = str_replace('`', '\\`', addslashes($table));
        $q = $this->dq("DESCRIBE `$table`");
        while ($r = $q->fetchRow()) {
            if ($r[0] == $field) return true;
        }
        return false;
    }
}