<?php
namespace ScummVM\Web\Models;

require_once('Models/BasicModel.php');
require_once('Objects/CompatGame.php');
require_once('XMLParser.php');
/**
 * The CompatibilityModel class will generate CompatGame objects.
 */
abstract class CompatibilityModel extends BasicModel
{
    const NO_VERSION = 'No version specified.';
    const NO_VERSION_TARGET = 'No version and/or target specified.';
    const NOT_FOUND = 'Did not find any games for the specified version.';
    const NO_FILES = 'No compatibility files found.';

    /* Get all the groups and the respectively demos for the specified ScummVM version. */
    public static function getAllData($version)
    {
        if (!is_string($version)) {
            throw new ErrorException(self::NO_VERSION);
        }
        $fname = DIR_COMPAT . "/compat-{$version}.xml";
        if (!file_exists($fname)) {
            throw new ErrorException(self::NO_FILES);
        }
        $parser = new XMLParser();
        $a = $parser->parseByFilename($fname);
        $entries = array();
        foreach ($a['compatibility']['company'] as $key => $value) {
            $games = array();
            if (is_array($value['games'])) {
                foreach ($value['games']['game'] as $data) {
                    $games[] = new CompatGame($data);
                }
                $entries[$value['name']] = $games;
            }
        }
        return $entries;
    }

    /**
     * Compares two version strings and returns an integer less than, equal
     * to, or greater than zero if the first argument is considered to be
     * respectively less than, equal to, or greater than the second.
     */
    public static function compareVersions($version1, $version2)
    {
        /* Get the length of the numeric part of the version strings. */
        $lenNumber1 = strspn($version1, ".0123456789");
        $lenNumber2 = strspn($version2, ".0123456789");
        if (($lenNumber1 == $lenNumber2) && (substr($version1, 0, $lenNumber1) == substr($version2, 0, $lenNumber2))) {
            /* Same version number. Handle special cases. */
            $extraVersion1 = substr($version1, $lenNumber1);
            $extraVersion2 = substr($version2, $lenNumber2);

            /* Release candidates go before the final release. */
            $rc1 = substr($extraVersion1, 0, 2);
            $rc2 = substr($extraVersion2, 0, 2);
            if (($rc1 == "rc") && ($rc2 != "rc")) {
                return -1;
            }
            if (($rc2 == "rc") && ($rc1 != "rc")) {
                return 1;
            }

            /* Break the tie with the standard comparison. */
        }
        return strnatcmp($version1, $version2);
    }

    /* Get version numbers for all available compatibility charts, excluding the DEV charts. */
    public static function getAllVersions()
    {
        if (!($files = scandir(DIR_COMPAT))) {
            throw new ErrorException(self::NO_FILES);
        }
        $dates = array();
        foreach ($files as $file) {
            if (substr($file, -4) != '.xml') {
                continue;
            }
            /* Always exclude the DEV-chart. */
            if (strpos($file, 'DEV') === false) {
                $dates[] = substr($file, (strpos($file, '-') + 1), -4);
            }
        }
        usort($dates, "CompatibilityModel::compareVersions");
        $dates = array_reverse($dates);
        return $dates;
    }

    /* Get a specific CompatGame-object for the requested version. */
    public static function getGameData($version, $target)
    {
        if (!is_string($version) || !is_string($target)) {
            throw new ErrorException(self::NO_VERSION_TARGET);
        }
        if (!($all_games = self::getAllData($version))) {
            throw new ErrorException(self::NOT_FOUND);
        }
        $g = null;
        foreach ($all_games as $company => $games) {
            foreach ($games as $game) {
                if ($game->getTarget() == $target) {
                    $g = $game;
                    break;
                }
            }
            if ($g != null) {
                break;
            }
        }
        if (is_null($g)) {
            throw new ErrorException(self::NOT_FOUND);
        }

        return $g;
    }
}