<?php

/*
 * File/attach API with the potential for revision control.
 *
 * TODO: a filesystem storage abstraction which maintains security (and 'data' contains a system filename
 * which is inaccessible from the web). This could get around PHP storage limits and store videos and larger
 * items, using fread or OS methods or native code to read/write or chunk it through.
 * Also an 'append' option to the storage function might be a useful addition. 
 */

require_once('include/permissions.php');

function z_mime_content_type($filename) {

	$mime_types = array(

		'txt' => 'text/plain',
		'htm' => 'text/html',
		'html' => 'text/html',
		'php' => 'text/html',
		'css' => 'text/css',
		'js' => 'application/javascript',
		'json' => 'application/json',
		'xml' => 'application/xml',
		'swf' => 'application/x-shockwave-flash',
		'flv' => 'video/x-flv',

		// images
		'png' => 'image/png',
		'jpe' => 'image/jpeg',
		'jpeg' => 'image/jpeg',
		'jpg' => 'image/jpeg',
		'gif' => 'image/gif',
		'bmp' => 'image/bmp',
		'ico' => 'image/vnd.microsoft.icon',
		'tiff' => 'image/tiff',
		'tif' => 'image/tiff',
		'svg' => 'image/svg+xml',
		'svgz' => 'image/svg+xml',

		// archives
		'zip' => 'application/zip',
		'rar' => 'application/x-rar-compressed',
		'exe' => 'application/x-msdownload',
		'msi' => 'application/x-msdownload',
		'cab' => 'application/vnd.ms-cab-compressed',

		// audio/video
		'mp3' => 'audio/mpeg',
		'wav' => 'audio/wav',
		'qt' => 'video/quicktime',
		'mov' => 'video/quicktime',
		'ogg' => 'application/ogg',

		// adobe
		'pdf' => 'application/pdf',
		'psd' => 'image/vnd.adobe.photoshop',
		'ai' => 'application/postscript',
		'eps' => 'application/postscript',
		'ps' => 'application/postscript',

		// ms office
		'doc' => 'application/msword',
		'rtf' => 'application/rtf',
		'xls' => 'application/vnd.ms-excel',
		'ppt' => 'application/vnd.ms-powerpoint',


		// open office
		'odt' => 'application/vnd.oasis.opendocument.text',
		'ods' => 'application/vnd.oasis.opendocument.spreadsheet',
	);

	$dot = strpos($filename,'.');
	if($dot !== false) {
		$ext = strtolower(substr($filename,$dot+1));
		if (array_key_exists($ext, $mime_types)) {
			return $mime_types[$ext];
		}
	}
// can't use this because we're just passing a name, e.g. not a file that can be opened
//	elseif (function_exists('finfo_open')) {
//		$finfo = @finfo_open(FILEINFO_MIME);
//		$mimetype = @finfo_file($finfo, $filename);
//		@finfo_close($finfo);
//		return $mimetype;
//	}
	else {
		return 'application/octet-stream';
	}
}


function attach_count_files($channel_id, $observer, $hash = '', $filename = '', $filetype = '') {

	$ret = array('success' => false);

	if(! perm_is_allowed($channel_id,$observer, 'read_storage')) {
		$ret['message'] = t('Permission denied.');
		return $ret;
	}

	require_once('include/security.php');
	$sql_extra = permissions_sql($channel_id);

	if($hash)
		$sql_extra .= protect_sprintf(" and hash = '" . dbesc($hash) . "' ");

	if($filename)
		$sql_extra .= protect_sprintf(" and filename like '@" . dbesc($filename) . "@' ");

	if($filetype)
		$sql_extra .= protect_sprintf(" and filetype like '@" . dbesc($filetype) . "@' ");

	$r = q("select id from attach where uid = %d $sql_extra",
		intval($channel_id)
	);

	$ret['success'] = ((is_array($r)) ? true : false);
	$ret['results'] = ((is_array($r)) ? count($r) : false);
	return $ret; 

}

function attach_list_files($channel_id, $observer, $hash = '', $filename = '', $filetype = '', $orderby = 'created desc', $start = 0, $entries = 0) {

	$ret = array('success' => false);

	if(! perm_is_allowed($channel_id,$observer, 'read_storage')) {
		$ret['message'] = t('Permission denied.');
		return $ret;
	}

	require_once('include/security.php');
	$sql_extra = permissions_sql($channel_id);

	if($hash)
		$sql_extra .= protect_sprintf(" and hash = '" . dbesc($hash) . "' ");

	if($filename)
		$sql_extra .= protect_sprintf(" and filename like '@" . dbesc($filename) . "@' ");

	if($filetype)
		$sql_extra .= protect_sprintf(" and filetype like '@" . dbesc($filetype) . "@' ");

	if($entries)
		$limit = " limit " . intval($start) . ", " . intval(entries) . " ";

	// Retrieve all columns except 'data'

	$r = q("select id, aid, uid, hash, filename, filetype, filesize, revision, folder, flags, created, edited, allow_cid, allow_gid, deny_cid, deny_gid from attach where uid = %d $sql_extra $orderby $limit",
		intval($channel_id)
	);

	$ret['success'] = ((is_array($r)) ? true : false);
	$ret['results'] = ((is_array($r)) ? $r : false);
	return $ret; 

}

// Find an attachment by hash and revision. Returns the entire attach structure including data. 
// This could exhaust memory so most useful only when immediately sending the data.  

function attach_by_hash($hash,$rev = 0) {

	$ret = array('success' => false);

	// Check for existence, which will also provide us the owner uid

	$sql_extra = '';
	if($rev == (-1))
		$sql_extra = " order by revision desc ";
	elseif($rev)
		$sql_extra = " and revision = " . intval($rev) . " ";


	$r = q("SELECT uid FROM attach WHERE hash = '%s' $sql_extra LIMIT 1",
		dbesc($hash)
	);
	if(! $r) {
		$ret['message'] = t('Item was not found.');
		return $ret;
	}

	if(! perm_is_allowed($r[0]['uid'],get_observer_hash(),'view_storage')) {
		$ret['message'] = t('Permission denied.');
		return $ret;
	}

	$sql_extra = permissions_sql($r[0]['uid']);

	// Now we'll see if we can access the attachment


	$r = q("SELECT * FROM attach WHERE hash = '%s' and uid = %d $sql_extra LIMIT 1",
		dbesc($hash),
		intval($r[0]['uid'])
	);

	if(! $r) {
		$ret['message'] =  t('Permission denied.');
		return $ret;
	}

	$ret['success'] = true;
	$ret['data'] = $r[0];
	return $ret;

}


function attach_by_hash_nodata($hash,$rev = 0) {

	$ret = array('success' => false);

	// Check for existence, which will also provide us the owner uid

	$sql_extra = '';
	if($rev == (-1))
		$sql_extra = " order by revision desc ";
	elseif($rev)
		$sql_extra = " and revision = " . intval($rev) . " ";

	$r = q("SELECT uid FROM attach WHERE hash = '%s' $sql_extra LIMIT 1",
		dbesc($hash)
	);
	if(! $r) {
		$ret['message'] = t('Item was not found.');
		return $ret;
	}

	if(! perm_is_allowed($r[0]['uid'],get_observer_hash(),'view_storage')) {
		$ret['message'] = t('Permission denied.');
		return $ret;
	}

	$sql_extra = permissions_sql($r[0]['uid']);

	// Now we'll see if we can access the attachment

	$r = q("select id, aid, uid, hash, filename, filetype, filesize, revision, folder, flags, created, edited, allow_cid, allow_gid, deny_cid, deny_gid from attach where uid = %d and hash = '%s' $sql_extra limit 1",
		intval($r[0]['uid']),
		dbesc($hash)
	);

	if(! $r) {
		$ret['message'] =  t('Permission denied.');
		return $ret;
	}

	$ret['success'] = true;
	$ret['data'] = $r[0];
	return $ret;

}


function attach_store($channel,$observer_hash,$options = '',$arr = null) {


	$ret = array('success' => false);
	$channel_id = $channel['channel_id'];
	$sql_options = '';

	if(! perm_is_allowed($channel_id,get_observer_hash(),'write_storage')) {
		$ret['message'] = t('Permission denied.');
		return $ret;
	}

	// The 'update' option sets db values without uploading a new attachment
	// 'replace' replaces the existing uploaded data
	// 'revision' creates a new revision with new upload data
	// Default is to upload a new file

	// revise or update must provide $arr['hash'] of the thing to revise/update

	if($options !== 'update') {
		if(! x($_FILES,'userfile')) {
			$ret['message'] = t('No source file.');
			return $ret;
		}

		$src      = $_FILES['userfile']['tmp_name'];
		$filename = basename($_FILES['userfile']['name']);
		$filesize = intval($_FILES['userfile']['size']);
	}

	$existing_size = 0;

	if($options === 'replace') {
		$x = q("select id, hash, filesize from attach where id = %d and uid = %d limit 1",	
			intval($replace),
			intval($channel_id)
		);
		if(! $x) {
			$ret['message'] = t('Cannot locate file to replace');
			return $ret;
		}
		$existing_id = $x[0]['id'];
		$existing_size = intval($x[0]['filesize']);
		$hash = $x[0]['hash'];
	}
	
	if($options === 'revise' || $options === 'update') {
		$sql_options = " order by revision desc ";
		if($options === 'update' &&  $arr && array_key_exists('revision',$arr))
			$sql_options = " and revision = " . intval($arr['revision']) . " ";

		$x =q("select id, aid, uid, filename, filetype, filesize, hash, revision, folder, flags, created, edited, allow_cid, allow_gid, deny_cid, deny_gid from attach where hash = '%s' and uid = %d $sql_options limit 1",
			dbesc($arr['hash']),
			intval($channel_id)
		);
		if(! $x) {
			$ret['message'] = t('Cannot locate file to revise/update');
			return $ret;
		}
		$hash = $x[0]['hash'];
	}

	// Check storage limits
	if($options !== 'update') {
		$maxfilesize = get_config('system','maxfilesize');

		if(($maxfilesize) && ($filesize > $maxfilesize)) {
			$ret['message'] = sprintf( t('File exceeds size limit of %d'), $maxfilesize);
			@unlink($src);
			return $ret;
		}

		$limit = service_class_fetch($channel_id,'attach_upload_limit');
		if($limit !== false) {
			$r = q("select sum(filesize) as total from attach where uid = %d ",
				intval($channel_id)
			);
			if(($r) &&  (($r[0]['total'] + $filesize) > ($limit - $existing_size))) {
				$ret['message'] = upgrade_message(true);
				@unlink($src);
				return $ret;
			}
		}
		$mimetype = z_mime_content_type($filename);
	}

	if(! isset($hash))
		$hash = random_string();
	$created = datetime_convert();

	if($options === 'replace') {
		$r = q("update attach set filename = '%s', filetype = '%s', filesize = %d, data = '%s', edited = '%s' where id = %d and uid = %d limit 1",
			dbesc($filename),
			dbesc($mimetype),
			intval($filesize),
			dbesc(@file_get_contents($src)),
			dbesc($created),
			intval($existing_id),
			intval($channel_id)
		);
	}
	elseif($options === 'revise') {
		$r = q("insert into attach ( aid, uid, hash, filename, filetype, filesize, revision, data, created, edited, allow_cid, allow_gid, deny_cid, deny_gid )
			VALUES ( %d, %d, '%s', '%s', '%s', %d, %d, '%s', '%s', '%s', '%s', '%s', '%s', '%s' ) ",
			intval($x[0]['aid']),
			intval($channel_id),
			dbesc($x[0]['hash']),
			dbesc($filename),
			dbesc($mimetype),
			intval($filesize),
			intval($x[0]['revision'] + 1),
			dbesc(@file_get_contents($src)),
			dbesc($created),
			dbesc($created),
			dbesc($x[0]['allow_cid']),
			dbesc($x[0]['allow_gid']),
			dbesc($x[0]['deny_cid']),
			dbesc($x[0]['deny_gid'])
		);
	}		

	elseif($options === 'update') {
		$r = q("update attach set filename = '%s', filetype = '%s', edited = '%s', 
			allow_cid = '%s', allow_gid = '%s', deny_cid = '%s', deny_gid  = '%s' where id = %d and uid = %d limit 1",
			dbesc((array_key_exists('filename',$arr))  ? $arr['filename']  : $x[0]['filename']),
			dbesc((array_key_exists('filetype',$arr))  ? $arr['filetype']  : $x[0]['filetype']),
			dbesc($created),
			dbesc((array_key_exists('allow_cid',$arr)) ? $arr['allow_cid'] : $x[0]['allow_cid']),
			dbesc((array_key_exists('allow_gid',$arr)) ? $arr['allow_gid'] : $x[0]['allow_gid']),
			dbesc((array_key_exists('deny_cid',$arr))  ? $arr['deny_cid']  : $x[0]['deny_cid']),
			dbesc((array_key_exists('deny_gid',$arr))  ? $arr['deny_gid']  : $x[0]['deny_gid']),
			intval($x[0]['id']),
			intval($x[0]['uid'])
		);
	}		

	else {
		$r = q("INSERT INTO attach ( aid, uid, hash, filename, filetype, filesize, revision, data, created, edited, allow_cid, allow_gid,deny_cid, deny_gid )
			VALUES ( %d, %d, '%s', '%s', '%s', %d, %d, '%s', '%s', '%s', '%s', '%s', '%s', '%s' ) ",
			intval($channel['channel_account_id']),
			intval($channel_id),
			dbesc($hash),
			dbesc($filename),
			dbesc($mimetype),
			intval($filesize),
			intval(0),
			dbesc(@file_get_contents($src)),
			dbesc($created),
			dbesc($created),
			dbesc(($arr && array_key_exists('allow_cid',$arr)) ? $arr['allow_cid'] : '<' . $channel['channel_hash'] . '>'),
			dbesc(($arr && array_key_exists('allow_gid',$arr)) ? $arr['allow_gid'] : ''),
			dbesc(($arr && array_key_exists('deny_cid',$arr))  ? $arr['deny_cid']  : ''),
			dbesc(($arr && array_key_exists('deny_gid',$arr))  ? $arr['deny_gid']  : '')
		);
	}		

	if($options !== 'update')
		@unlink($src);

	if(! $r) {
		$ret['message'] = t('File upload failed. Possible system limit or action terminated.');
		return $ret;
	}

	// Caution: This re-uses $sql_options set further above

	$r = q("select id, aid, uid, hash, filename, filetype, filesize, revision, folder, flags, created, edited, allow_cid, allow_gid, deny_cid, deny_gid from attach where uid = %d and hash = '%s' $sql_options limit 1",
		intval($channel_id),
		dbesc($hash)
	);

	if(! $r) {
		$ret['message'] = t('Stored file could not be verified. Upload failed.');
		return $ret;
	}

	$ret['success'] = true;
	$ret['data'] = $r[0];
	return $ret;
}