KeySetDiffer.php

<?php

namespace clentfort\LaravelFindJsLocalizations;

use Illuminate\Support\Collection;

class KeySetDiffer
{
    /**
     * Builds a list of keys that are missing in the given KeySet.
     *
     * @param Collection $keys   A collection of $keys to
     *                           check the translation status
     *                           for
     * @param KeySet     $keySet The KeySet used to read files
     *
     * @return Collection A nested collection of untranslated keys. The
     *                    structure is `[prefix => [keys]]`. Where `prefix` is a
     *                    common prefix shared by all keys in that collection.
     *                    I.e for the string `some.string` and
     *                    `some.otherstring` the collection would look liked
     *                    `['some' => ['string', 'otherstring']]`.
     */
    public static function diffKeys(
        KeySet $keySet,
        Collection $keys
    ) {
        // Translations are stored in "prefix"-files. This means a key
        // `some.string` will be saved in `some.php` with the index `string`.
        $groupedKeys = static::groupKeysByPrefix($keys);

        $groupedNewKeys = new Collection();

        foreach ($groupedKeys as $prefix => $keys) {
            $currentKeys = $keySet->getKeysWithPrefix($prefix);
            $newKeys = $keys->diff($currentKeys->keys());

            if (!$newKeys->isEmpty()) {
                $groupedNewKeys[$prefix] = $newKeys;
            }
        }

        return $groupedNewKeys;
    }

    /**
     * Groups the keys in $keys by their common prefix and removes the prefix
     * from the elements in a group.
     *
     * @param Collection $keys
     *
     * @return Collection A collection of collections of the form
     *                    `['common_prefix' => ['key1', 'key2', ...]]`.
     */
    protected static function groupKeysByPrefix(Collection $keys)
    {
        return $keys->unique()->groupBy(function ($key) {
            return strstr($key, '.', true);
        })->map(function ($group) {
            return $group->map(function ($key) {
                return mb_substr(strstr($key, '.'), 1);
            });
        });
    }
}