1: <?php
 2: /**
 3:  * Copyright 2012-2014 Rackspace US, Inc.
 4:  *
 5:  * Licensed under the Apache License, Version 2.0 (the "License");
 6:  * you may not use this file except in compliance with the License.
 7:  * You may obtain a copy of the License at
 8:  *
 9:  * http://www.apache.org/licenses/LICENSE-2.0
10:  *
11:  * Unless required by applicable law or agreed to in writing, software
12:  * distributed under the License is distributed on an "AS IS" BASIS,
13:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14:  * See the License for the specific language governing permissions and
15:  * limitations under the License.
16:  */
17: 
18: namespace OpenCloud\Image\Resource\JsonPatch;
19: 
20: use OpenCloud\Image\Enum\Document as DocumentEnum;
21: 
22: /**
23:  * Class that encodes a JSON document object into a flat string format
24:  *
25:  * @package OpenCloud\Images\Resource\JsonPatch
26:  */
27: class Encoder
28: {
29:     /** @var array Required transformations for reserved characters */
30:     protected static $transformations = array(
31:         '~' => '~0',
32:         '/' => '~1'
33:     );
34: 
35:     /**
36:      * Encode the
37:      * @param array $operations
38:      * @return string
39:      */
40:     public static function encode(array $operations)
41:     {
42:         $lines = array();
43: 
44:         foreach ($operations as $operation) {
45:             $lines[] = sprintf(
46:                 '{"%s": "%s", "%s": "%s", "%s": "%s"}',
47:                 DocumentEnum::OP, $operation->getType(),
48:                 DocumentEnum::PATH, $operation->getPath(),
49:                 DocumentEnum::VALUE, self::transform($operation->getValue())
50:             );
51:         }
52: 
53:         return sprintf('[%s]', implode($lines, ','));
54:     }
55: 
56:     /**
57:      * Search a given string and transform any reserved characters into their safe version
58:      *
59:      * @param $value
60:      * @return string
61:      */
62:     public static function transform($value)
63:     {
64:         return strtr((string) $value, self::$transformations);
65:     }
66: }
67: