multidimensional array conversion is not working

Question

Very frustrating moment and could not figure out and finally decided to move and ask to Geeks about solution.

Okay, Here is the problem.

I have below array and need to convert it by replacing repeating records from array and merge is as shown below.

Array
(
    [0] => Array
    (
        [Index] => Array
        (
            [id] => 2
            [content] => content 2
            [user_id] => 1
            [page_number] => 25
            [book_id] => 1
            [tag_id] => 3,2,4
            [need_review] => no
            [status] => active
            [created] => 2013-06-27 12:36:45
            [modified] => 2013-06-27 12:36:45
        )
        [Tag] => Array
        (
            [id] => 3
            [name] => three
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:32:13
            [modified] => 2013-06-27 12:32:13
        )
        [Book] => Array
        (
            [id] => 1
            [name] => Book 1
            [description] => book one
            [ordervalue] => 0
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:22:26
            [modified] => 2013-06-27 12:22:26
        )
    )
    [1] => Array
    (
        [Index] => Array
        (
            [id] => 2
            [content] => content 2
            [user_id] => 1
            [page_number] => 25
            [book_id] => 1
            [tag_id] => 3,2,4
            [need_review] => no
            [status] => active
            [created] => 2013-06-27 12:36:45
            [modified] => 2013-06-27 12:36:45
        )
        [Tag] => Array
        (
            [id] => 2
            [name] => two
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:31:58
            [modified] => 2013-06-27 12:31:58
        )
        [Book] => Array
        (
            [id] => 1
            [name] => book 1
            [description] => book one
            [ordervalue] => 0
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:22:26
            [modified] => 2013-06-27 12:22:26
        )

    )
    [2] => Array
    (
        [Index] => Array
        (
            [id] => 1
            [content] => content1
            [user_id] => 1
            [page_number] => 10
            [book_id] => 2
            [tag_id] => 1,2,3
            [need_review] => no
            [status] => active
            [created] => 2013-06-27 12:32:17
            [modified] => 2013-06-27 12:32:17
        )
        [Tag] => Array
        (
            [id] => 3
            [name] => three
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:32:13
            [modified] => 2013-06-27 12:32:13
        )
        [Book] => Array
        (
            [id] => 2
            [name] => book2
            [description] => book two
            [ordervalue] => 2
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:24:04
            [modified] => 2013-06-27 12:24:04
        )
    )
    [3] => Array
    (
        [Index] => Array
        (
            [id] => 1
            [content] => content1
            [user_id] => 1
            [page_number] => 10
            [book_id] => 2
            [tag_id] => 1,2,3
            [need_review] => no
            [status] => active
            [created] => 2013-06-27 12:32:17
            [modified] => 2013-06-27 12:32:17
        )
        [Tag] => Array
        (
            [id] => 2
            [name] => two
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:31:58
            [modified] => 2013-06-27 12:31:58
        )
        [Book] => Array
        (
            [id] => 2
            [name] => book2
            [description] => book two
            [ordervalue] => 2
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:24:04
            [modified] => 2013-06-27 12:24:04
        )
    )
)

I want to convert this array into below.

Array
(
    [0] => Array
    (
        'Tag' => Array
        (
            [id] => 2
            [name] => two
            [user_id] => 1
            [status] => active
            [created] => 2013-06-27 12:31:58
            [modified] => 2013-06-27 12:31:58,
            [Book] => Array
            (
                [id] => 2
                [name] => book2
                [description] => book two
                [ordervalue] => 2
                [user_id] => 1
                [status] => active
                [created] => 2013-06-27 12:24:04
                [modified] => 2013-06-27 12:24:04
                [Index] => Array
                (
                    '0' => Array
                    (
                        [id] => 1
                        [content] => content1
                        [user_id] => 1
                        [page_number] => 10
                        [book_id] => 2
                        [tag_id] => 1,2,3
                        [need_review] => no
                        [status] => active
                        [created] => 2013-06-27 12:32:17
                        [modified] => 2013-06-27 12:32:17
                    ),
                    '1' => Array
                    (
                        [id] => 2
                        [content] => content 2
                        [user_id] => 1
                        [page_number] => 25
                        [book_id] => 1
                        [tag_id] => 3,2,4
                        [need_review] => no
                        [status] => active
                        [created] => 2013-06-27 12:36:45
                        [modified] => 2013-06-27 12:36:45
                    )
                )
            )
        )
    )
)

and so on.

What i have tried?

$newindexes = array();
for( $i = 0; $i < count($indexes);$i++ )
{
    $newindexes[$i]['Book']          = $indexes[$i]['Book'];
    $newindexes[$i]['Book']['Index'] = array();

    for( $k = 0; $k < count($indexes);$k++ )
    {
        if($indexes[$i]['Book']['id'] == $indexes[$k]['Book']['id'])
        {
            $newindexes[$i]['Book']['Index'][] = $indexes[$k]['Index'];
        }
    }
}

and added $newindexes = array_map("unserialize", array_unique(array_map("serialize", $newindexes))); at the end for removing duplicates but still not working.

Spent almost 4-5 hours but could not figure it out.

Please guys take a look and give me some correction in my code or provide me a helpful link.

Thanks a lot.

Answer 1

Here is a less robust answer that I would give to do what you ask, provided that all tag ids, book ids, and index ids are unique:

foreach($indexes as $index){
    $tagid = (int) $index['Tag']['id'];
    $bookid = (int) $index['Book']['id'];
    $indexid = (int) $index['Index']['id'];
    if(!isset($newindexes[$tagid])) {
        $newindexes[$tagid]['Tag'] = $index['Tag'];
    }
    if(!isset($newindexes[$tagid]['Tag']['Book']) || !isset($newindexes[$tagid]['Tag']['Book'][$bookid])) {
        $newindexes[$tagid]['Tag']['Book'][$bookid] = $index['Book'];
    }
    if(!isset($newindexes[$tagid]['Tag']['Book'][$bookid]['Index']) || !isset($newindexes[$tagid]['Tag']['Book'][$bookid]['Index'][$indexid])) {
        $newindexes[$tagid]['Tag']['Book'][$bookid]['Index'][$indexid] = $index['Index'];
    }
}