<?php

/**
 * Created by PhpStorm.
 * User: leanderschmedemann
 * Date: 02/03/2017
 * Time: 09:59
 */

require_once('includes.inc.php');

class Database
{
    private $db;

    function __construct() {
        $this->db = pg_connect(
            "host=".DATABASE_URL.
            " dbname=".DATABASE_NAME.
            " user=".DATABASE_USER.
            " password=".DATABASE_PASSWORD);
    }

    // Execute $sql unsing array $params as params when needed.
    function query($sql, $params = null) {
        $result = null;
        $error = 0;
        if(isset($params)) {
            $result = @pg_query_params($this->db, $sql, $params);
        } else {
            $result = @pg_query($this->db, $sql);
        }
        if(!$result) {
            $error = 10101;
        }
        if($error == 0) {
            $data = pg_fetch_all($result);
        } else {
            $data = null;
        }
        $query_response = array('data' => $data, 'error' => $error);
        return $query_response;
    }

    // Create response to API request.
    static function create_response($data, $error, $values = null) {
        $status_message = Database::create_status_code($error, $values);
        $meta = array('status'=>$error, 'message'=>$status_message);
        if($error != 0){
            $data = '';
        }
        $response_element_json = json_encode(array('meta'=>$meta, 'data'=>$data), JSON_PRETTY_PRINT);
        return $response_element_json;
    }

    // Create status message from status code.
    static function create_status_code($error, $values) {
        switch ($error) {
            case 0:
                return 'Success.';
            case 10101:
                return 'SQL statement did not give a result.';
            case 11101:
            case 14101:
                return 'User name does not match rules. User name must be 6 to 20 characters and consist of English letters and numbers only.';
            case 11102:
            case 14103:
                return 'User name already exists. Please pick a different name.';
            case 12101:
            case 13101:
            case 14102:
            case 15101:
            case 16101:
                return 'User ID not specified. This is an internal error.';
            case 12102:
                return 'A game without a question is not possible. Please select new game length.';
            case 12103:
                return 'Sorry, we only have '.$values[0].' questions. Please try again.';
            case 12104:
            case 14104:
            case 15102:
            case 16102:
                return 'The specified user ID does not exist. This is an internal error.';
            case 13102:
                return 'No valid time specified. This is an internal error.';
            case 13103:
                return 'No chosen answer specified. This is an internal error.';
            case 13104:
                return 'No game for specified user name. This is an internal error.';
            case 13105:
                return 'The correct token was not provided. This is an internal error.';
            default:
                return 'An unknown error occurred.';
        }
    }
}
?>