<?php

namespace CorpusParole\Libraries;

use EasyRdf\Literal;

use EasyRdf\Resource;

use EasyRdf\Graph;

/**

 * Utilities functions

 */

class Utils {

    /**

     * convert DateIntervals to milliseconds

     * Months and year calculated by approximation based on average number

     * of days over 4 years (365*4+1)

     * @param \DateInterval $di the date interval

     * @return the number of milliseconds or 0 if $di is null

     */

    public static function dateIntervalToMillis(\DateInterval $di) {

        if(is_null($di)) {

            return null;

        }

        $seconds = ($di->s)

         + ($di->i * 60)

         + ($di->h * 60 * 60)

         + ($di->d * 60 * 60 * 24)

         + ($di->m * (365*4+1)/48*60*60*24)

         + ($di->y * (365*4+1)/4*60*60*24);

        return $seconds*1000;

    }

    /**

     * convert iso8601 strings to milliseconds

     * Months and year calculated by approximation based on average number

     * of days over 4 years (365*4+1)

     *

     * @param str iso8601 string

     * @return the number of milliseconds or 0 if $str is null

     */

    public static function iso8601IntervalToMillis($str) {

        if(is_null($str)) {

            return null;

        }

        elseif( $str === '') {

            return 0;

        }

        $di = new \DateInterval($str);

        return self::dateIntervalToMillis($di);

    }

    /*

     * From http://www.thecave.info/php-get-mime-type-from-file-extension/

     */

    public static function getMimetype($file) {

        // our list of mime types

        $mime_types = array(

                "pdf"=>"application/pdf",

                "exe"=>"application/octet-stream",

                "zip"=>"application/zip",

                "docx"=>"application/msword",

                "doc"=>"application/msword",

                "xls"=>"application/vnd.ms-excel",

                "ppt"=>"application/vnd.ms-powerpoint",

                "gif"=>"image/gif",

                "png"=>"image/png",

                "jpeg"=>"image/jpg",

                "jpg"=>"image/jpg",

                "mp3"=>"audio/mpeg",

                "wav"=>"audio/x-wav",

                "mpeg"=>"video/mpeg",

                "mpg"=>"video/mpeg",

                "mpe"=>"video/mpeg",

                "mov"=>"video/quicktime",

                "avi"=>"video/x-msvideo",

                "3gp"=>"video/3gpp",

                "css"=>"text/css",

                "jsc"=>"application/javascript",

                "js"=>"application/javascript",

                "php"=>"text/html",

                "htm"=>"text/html",

                "html"=>"text/html",

                "mp4"=>"video/mp4",

                "ogg"=>"video/ogg",

                "xml"=>"application/xml",

                "xhtml"=>"application/xhtml+xml",

        );

        $split_ext = explode('.',$file);

        $extension = strtolower(end($split_ext));

        return $mime_types[$extension];

    }

    public static function processLiteralResourceOrString($val) {

        if(is_null($val)) {

            return $val;

        }

        if($val instanceof Literal) {

            if(empty($val->getLang()) && empty($val->getDatatypeURI())) {

                return $val->getValue();

            }

            else {

                return [

                    'value'=> $val->getValue(),

                    'datatype'=> $val->getDatatypeURI(),

                    'lang'=> $val->getLang()

                ];

            }

        }

        elseif ($val instanceof Resource) {

            return $val->getUri();

        }

        else {

            return (string)$val;

        }

    }

    /**

     * @param EasyRdf\Graph $graph1

     * @param EasyRdf\Graph $graph2

     *

     * @return EasyRdf\Graph

     */

    public static function mergeGraphs(Graph $graph1, Graph $graph2)

    {

        $data1 = $graph1->toRdfPhp();

        $data2 = $graph2->toRdfPhp();

        $merged = array_merge_recursive($data1, $data2);

        unset($data1, $data2);

        return new Graph($graph1->getUri(), $merged, 'php');

    }

    /**

     * From http://stackoverflow.com/a/834355

     */

    public static function startsWith($haystack, $needle)

    {

        $length = strlen($needle);

        return (substr($haystack, 0, $length) === $needle);

    }

    /**

     * From http://stackoverflow.com/a/834355

     */

    public static function endsWith($haystack, $needle)

    {

        $length = strlen($needle);

        if ($length == 0) {

            return true;

        }

        return (substr($haystack, -$length) === $needle);

    }

}