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[0] in function chmod in /var/www/hopeinstoughton_www/wp-content/plugins/simple-universal-google-analytics/main.php on line 8
[1] in function include_once in /var/www/hopeinstoughton_www/wp-settings.php on line 560
[2] in function require_once in /var/www/hopeinstoughton_www/wp-config.php on line 85
[3] in function require_once in /var/www/hopeinstoughton_www/wp-load.php on line 50
[4] in function require_once in /var/www/hopeinstoughton_www/wp-blog-header.php on line 13
[5] in function require in /var/www/hopeinstoughton_www/index.php on line 17

<?php

class MediaSource {
    
    private $db;
    private $data;
    private $basename;
    private $mmitem;
    private $media;

    const ARIES = 1;
    const HOSTZ = 2;
    const CHURCH = 3;
    const BACKUP1 = 4;  // Home

    // 256bit key, generated using https://csfieldguide.org.nz/en/interactives/rsa-key-generator/
    const KEY_PRIVATE = <<<BLOCK
-----BEGIN RSA PRIVATE KEY-----
MIGqAgEAAiEAz/aF1DSTz4duSmvTKItkZE/8sxfnQhUl4rks26KbgwECAwEAAQIg
RIgr8BNnhmNOAC5qRpkw+pmYu66OvdZmvUhXrHGqfHUCEQDr58xGtxKWAlk+otdO
bK8PAhEA4a1nyqbkxT7T2Lc3ghqs7wIRALlyU/x3KC4ylHOP0Y++EnMCEG2fyUpE
ld5GrauZHGqjwJsCECC4AJInN24VvWe5ealG/bs=
-----END RSA PRIVATE KEY-----

BLOCK;

    const KEY_PUBLIC = <<<BLOCK
-----BEGIN RSA PUBLIC KEY-----
MCgCIQDP9oXUNJPPh25Ka9Moi2RkT/yzF+dCFSXiuSzbopuDAQIDAQAB
-----END RSA PUBLIC KEY-----

BLOCK;
    
    public function __construct() {
        $this->data = NULL;
        $this->media = NULL;
    }
    
    public function Db() {
        if (func_num_args()) {
            $this->db = func_get_arg(0);
            return $this;
        }
        return $this->db;
    }
    public function BaseFilename() {        // filename without path or extension
        if (func_num_args()) {
            $this->basename = func_get_arg(0);
            return $this;
        }
        return $this->basename;
    }

    public function MmItem() {        // mm_item object from the database.  must have `mi_id` property
        if (func_num_args()) {
            $this->mmitem = func_get_arg(0);
            return $this;
        }
        return $this->mmitem;
    }

    public function Media() {         // items from the mm_media table
        if (func_num_args()) {
            $this->media = func_get_arg(0);
            return $this;
        }
        return $this->media;
    }
    
    public function Load() {
        $rows = $this->db->get_results('select ms_id,ms_name,ms_url,ms_path,ms_mountfile from `mm_source` order by ms_id');
        $this->data = [];
        foreach($rows as $row) {
            $id = $row->ms_id;
            $this->data[$id] = $row;
        }
    }
    
    public function generateDownloadLink($target, $downloadname, $action = 'file') {
        if ($this->data === NULL) $this->Load();
        $p = strrpos($downloadname, '.');
        $ext = substr($downloadname, $p + 1);
        $base = substr($downloadname, 0, $p);
        if ($base == '') $downloadname = '';
        $id = $this->mmitem->mi_id;
        $auth = $this->generateAuth($ext);
        $link = $this->data[$target]->ms_url . '/' . $action . '/' . $auth;
        if ($downloadname != '') $link .= '/' . $downloadname;
        return $link;
    }
    
    // save file to filesystem
    // get file info
    
    public function getListing() {

        if ($this->data === NULL) $this->Load();
        
        $hasVTT = 0;
        $hasJPG = 0;
        foreach($this->media as $item) {
            switch($item->mm_type) {
                case 'vtt':
                    $hasVTT = 1;
                    break;
                case 'jpg':
                    $hasJPG = 1;
                    break;
            }
        }
        
        $rows = [];
        foreach($this->media as $item) {
            $ext = $item->mm_type;
            $source_id = $item->mm_source;
            $source_info = $this->data[$source_id];
            if ($ext == 'mp3' && isset($item->mm_other->ext)) {
				$ext = $item->mm_other->ext;
			}
            
            $base = ($ext == 'vtt' || $ext == 'xml' || $ext == 'html' || $ext == 'zip') ? $this->mmitem->mi_id : $this->basename;
            $node = [
                'i_type'     => $ext,
                'i_filename' => $base . '.' . $ext,
                'source'     => $source_id,
//                        'name'       => $source_info->ms_name,
                'base'       => $source_info->ms_path,
                'url'        => $source_info->ms_url,
                'i_filesize' => static::formatBytes($item->mm_filesize),
                'i_dimension'=> $item->mm_framesize,
                'i_location' => $source_info->ms_name,
                'i_flags'    => '',
                'auth'       => $this->generateAuth($ext),
            ];
            $duration = (int) $item->mm_duration;
            if ($duration > 3599) {
                $hours = floor($duration / 3600);
                $duration %= 3600;
                $duration = sprintf('%d:%02d:%02d', $hours, floor($duration / 60), $duration % 60);
            } elseif ($duration) {
                $duration = sprintf('%02d:%02d', floor($duration / 60), $duration % 60);
            } else {
                $duration = '';
            }
            $node['i_duration'] = $duration;

            if ($ext == 'mp3' || $ext == 'm4a') {
                $node['present_vtt'] = $hasVTT;
                $node['info'] = (array) $item->mm_other;
                unset($node['info']['bitrate'], $node['info']['frequency']);
            }
            if ($ext == 'mp4') {
                $node['present_jpg'] = $hasJPG;
            }
            $rows[] = $node;
        }

        return $rows;
    }
    
    public function determineBestServer($serverbitmap, $asURL = FALSE) {
        if ($this->data === NULL) $this->Load();
        if ($serverbitmap & (1 << self::ARIES)) {
            return self::ARIES;           // Alcor is the best
        }
//        if ($asURL && $serverbitmap & (1 << self::HOSTZ)) {
//            return self::HOSTZ;           // Hostz, if present should be primary source for downloads
//        }
        foreach($this->data as $key => $value) {
            $mask = 1 << $key;
            if ($serverbitmap & $mask) {
                if (!$asURL) {      // if the media is not mounted, ignore it
                    $specialfile = $this->data[$key]->ms_path . '/' . $this->data[$key]->ms_mountfile;
                    if (!file_exists($specialfile)) continue;
                }
                return $key;
            }
        }
        return NULL;            // not present anywhere :(
    }
    
    public function getDestination($target, $filename) {
        if ($this->data === NULL) $this->Load();
        $targetdir = $this->data[$target]->ms_path . '/' . substr($filename, 0, 1);
        if (!is_dir($targetdir)) {
            mkdir($targetdir, 0777, TRUE);
        }
        return $targetdir . '/' . $filename;
    }
    
    public function getHost($target) {
        if ($this->data === NULL) $this->Load();
        return $this->data[$target]->ms_url;
    }

    private function _getOldMoorestownFolder($src) {
        if ($src == 3) return '/mnt/church/av/moorestown';      // mp3. should use ms_path
        if ($src == 1) return '/var/www/hopeinstoughton_www/av/moorestown-vtt';
        die('unknown location ' . $src);
    }

    // copy a file from a source server to a target
    //      filename does not contain path
    //      sources is a bitmap of servers containing the requested file
    //      target is a ms_id
    //      datatype is used to determine where the source file is located
    public function CopyFile($filename, $sources, $target, $datatype = NULL) {
        if ($this->data === NULL) $this->Load();
        $src = $this->determineBestServer($sources);
        if ($datatype == 'mt' && ($src == 3 || $src == 1)) {
            $sourcefile = $this->_getOldMoorestownFolder($src) . '/' . $filename;
        } else {
            echo('unable to determine source path (' . $src . ') for ' . $filename . "<br>\n");
            return FALSE;
        }
        $destfile = $this->getDestination($target, $filename);  // this will create folders if needed
        if (!file_exists($destfile)) {
            copy($sourcefile, $destfile);       // server-to-server transfer
            @chmod($destfile, 0666);
            return 1;       // not existing, copied
        }
        return 2;           // exists, so not copied
    }

	private function _encryptPayload($privatekey, $payload) {
		$key = openssl_pkey_get_private($privatekey);

		// encrypt
		$det = openssl_pkey_get_details($key);
		$blocksize = intval(($det['bits'] - 88) / 8);
		$output = '';
		foreach(str_split($payload, $blocksize) as $chunk) {
			$encrypted = '';
			$j = openssl_private_encrypt($chunk, $encrypted, $key, OPENSSL_PKCS1_PADDING );
			if ($j === FALSE) return FALSE;		// failed to encrypt - bad key
			$output .= $encrypted;
		}
		return base64_encode($output);
	}

    // 256bit key can encrypt blocks of 21 bytes
    // requires Id() set
    // payload: 3byte ext, 4byte exp, remaining = identifier
    public function generateAuth($ext, $ttl = 3600) {
        if (empty($this->mmitem->mi_id)) die('id not specified');
        $id = substr($this->mmitem->mi_id, 0, 14);
        $exp = time() - 1630000000;
        $payload = pack('A3Va14', $ext, $exp + $ttl, $id);
        $encrypted = $this->_encryptPayload(self::KEY_PRIVATE, $payload);
        $encrypted = str_replace(['+', '/'], ['-', '_'], $encrypted);
        return $encrypted;
    }
    
	private function _decryptPayload($private_key, $data) {
        $key = openssl_pkey_get_private($private_key);
		$info = openssl_pkey_get_details($key);
		$pub = $info['key'];
		$key = openssl_pkey_get_public($pub);
		
		$blocksize = ceil(($info['bits']) / 8);
		$output = '';
		foreach(str_split($data, $blocksize) as $block) {
			$decrypted = '';
			if (!openssl_public_decrypt($block, $decrypted, $key)) {
				return FALSE;	// not using this key
			}
			$output .= $decrypted;
		}
		return $output;
	}
    
    public function decodeAuth($payload) {
        $payload = base64_decode(str_replace(['-', '_'], ['+', '/'], $payload));
        $data = $this->_decryptPayload(self::KEY_PRIVATE, $payload);
        $result = new StdClass;
        $result->valid = !empty($data);
        $result->expired = TRUE;
        if ($result->valid) {
            $info = unpack('A3ext/Vexp/a14id', $data);
            $result->id = trim($info['id']);
            $result->expiry = $info['exp'] + 1630000000;
            $result->ext = trim($info['ext']);
            $result->expired = time() > $result->expiry;
        }
        return $result;
    }

    static     
    public function formatBytes($bytes, $precision = 2) { 
        $units = array('B', 'KiB', 'MiB', 'GiB', 'TiB'); 

        $bytes = max($bytes, 0); 
        $pow = floor(($bytes ? log($bytes) : 0) / log(1024)); 
        $pow = min($pow, count($units) - 1); 

        $bytes /= pow(1024, $pow);
        return round($bytes, $precision) . ' ' . $units[$pow]; 
    } 

}