1 | <?php |
---|
2 | /** |
---|
3 | * Name: When_Iterator |
---|
4 | * Author: Thomas Planer <tplaner@gmail.com> |
---|
5 | * Location: http://github.com/tplaner/When |
---|
6 | * Created: November 2010 |
---|
7 | * Description: Implements PHP's Object Iteration Interface (http://us.php.net/Iterator & http://php.net/manual/en/class.iterator.php) so you can use the object within a foreach loop. |
---|
8 | * |
---|
9 | * Thanks to Andrew Collington for suggesting the implementation of an Iterator and supplying the base code for it. |
---|
10 | */ |
---|
11 | |
---|
12 | require_once('When.php'); |
---|
13 | |
---|
14 | class When_Iterator extends When implements Iterator |
---|
15 | { |
---|
16 | // store the current position in the array |
---|
17 | protected $position = 0; |
---|
18 | |
---|
19 | // store an individual result if caching is disabled |
---|
20 | protected $result; |
---|
21 | |
---|
22 | // store all of the results |
---|
23 | protected $results = array(); |
---|
24 | |
---|
25 | protected $cache = false; |
---|
26 | |
---|
27 | // caching the results will cause the script to |
---|
28 | // use more memory but less cpu (should also perform quicker) |
---|
29 | // |
---|
30 | // results should always be the same regardless of cache |
---|
31 | public function __construct($cache = false) |
---|
32 | { |
---|
33 | parent::__construct(); |
---|
34 | |
---|
35 | $this->position = 0; |
---|
36 | $this->results = array(); |
---|
37 | $this->cache = $cache; |
---|
38 | } |
---|
39 | |
---|
40 | public function rewind() |
---|
41 | { |
---|
42 | if($this->cache) |
---|
43 | { |
---|
44 | $this->position = 0; |
---|
45 | } |
---|
46 | else |
---|
47 | { |
---|
48 | // reset the counter and try_date in the parent class |
---|
49 | $this->counter = 0; |
---|
50 | $this->try_date = clone $this->start_date; |
---|
51 | } |
---|
52 | } |
---|
53 | |
---|
54 | public function current() |
---|
55 | { |
---|
56 | if($this->cache === true) |
---|
57 | { |
---|
58 | return $this->results[$this->position]; |
---|
59 | } |
---|
60 | else |
---|
61 | { |
---|
62 | return $this->result; |
---|
63 | } |
---|
64 | } |
---|
65 | |
---|
66 | // only used if caching is enabled |
---|
67 | public function key() |
---|
68 | { |
---|
69 | return $this->position; |
---|
70 | } |
---|
71 | |
---|
72 | // only used of caching is enabled |
---|
73 | public function next() |
---|
74 | { |
---|
75 | ++$this->position; |
---|
76 | } |
---|
77 | |
---|
78 | public function valid() |
---|
79 | { |
---|
80 | if($this->cache === true) |
---|
81 | { |
---|
82 | // check to see if the current position has already been stored |
---|
83 | if(!empty($this->results[$this->position])) |
---|
84 | { |
---|
85 | return isset($this->results[$this->position]); |
---|
86 | } |
---|
87 | // if it hasn't been found, check to see if there are more dates |
---|
88 | elseif($next_date = parent::next()) |
---|
89 | { |
---|
90 | $this->results[] = $next_date; |
---|
91 | return isset($next_date); |
---|
92 | } |
---|
93 | } |
---|
94 | else |
---|
95 | { |
---|
96 | // check to see if there is another result and set that as the result |
---|
97 | if($next_date = parent::next()) |
---|
98 | { |
---|
99 | $this->result = $next_date; |
---|
100 | return isset($this->result); |
---|
101 | } |
---|
102 | } |
---|
103 | |
---|
104 | // end the foreach loop when all options are exhausted |
---|
105 | return false; |
---|
106 | } |
---|
107 | |
---|
108 | public function enable_cache($cache) |
---|
109 | { |
---|
110 | $this->cache = $cache; |
---|
111 | } |
---|
112 | } |
---|