Generating language changing urls in laravel - php

Question

I have decided to prefix all my routes with a $locale-variable. This is code found from googling:
$locale = Request::segment(1);
if (in_array($locale, Config::get('app.available_locales'))) {
App::setLocale($locale);
} else {
$locale = null;
}
Route::group(array('prefix' => $locale), function() {
//All my routes
});
Now, I would like to generate URL:s dynamically for jumping between locales. I want a way to generate the current url or route, but replace the $locale-parameter. You should be able to write something similar to this pseudocode:
route(Route::Current(), [$locale => 'foo'])
Question:
I want to take my current URL and replace one argument in it. How do I do that?
Update 1:
Giving my route a name, I'm able to do this:
route('index', 'foo') //Gives mywebsite.com?foo
This however, does not produce the wanted result, mywebsite.com/foo. It instead generates mywebsite.com?foo. My guess is that route doesn't understand that this route is nested and prefixed with a fragment, so it treats my argument as a parameter instead. Specifying that it is the locale I want to change does not help:
route('index', ['locale' => 'foo']) //Gives mywebsite.com?locale=foo
Update 2:
Changing the prefix to instead say:
Route::group(array('prefix' => '{locale?}'), function() {
Makes route() work:
route('index', ['locale' => 'foo']) //Gives mywebsite.com/foo
It does however ruin some url:s inside the group, as some of them start with variables. The following route inside the route-group stops working:
Route::get('/{id}', 'FooController#showFoo');
As routes.php interprets the url mywebsite.com/foo as 'foo' now being the language. If there is some way to set a default value in routes.php for locale so that you could write it as {route} instead of {route?} and have it redirect to a default locale if it was missing, the problem would be solved.
Update 3:
Moving in the direction of having 'prefix' => '{locale?}' instead leads into way too many sub-problems to be worth pursuing. The issue comes back to generating urls from the current url but inserting language into the url. I am currently considering doing this with just a regex replacement because it is the most straight-forward solution.

Answer 1

I didn't test this, but you could try to do it like this way.
If no parameter is given, you can easily redirect to the default locale route. If first parameter is given, you need to check if it's a correct locale.
use Illuminate\Support\Facades\Request;
$defaultLocale = 'en';
Route::get('/', function() use ($defaultLocale) {
return redirect('/' . $defaultLocale);
});
Route::group(array('prefix' => '{locale}'), function($locale) use ($defaultLocale) {
if(!in_array($locale, Config::get('app.available_locales'))) {
return redirect('/' . $defaultLocale . '/' . Request::path());
}
// All your routes
});

Answer 2

So I ended up not solving this with laravel magic, I wrote my own code.
The Route::Group remains the same, the code I use to create URL:s to different languages looks like this:
<a href="{{ change_locale_url('en') }}"</a>
The change_locale_url-function is just a regex function which uses URL::Current to get the current url and then either inserts or replaces the input string as a language parameter in the url.
When I'm on mywebsite.com/about, the function outputs mywebsite.com/en/about
When I'm on www.mywebsite.com/de/about, the function outputs www.mywebsite.com/en/about
When I'm on http://mywebsite.com, the function outputs http://mywebsite.com/en
As a reminder, when using this route group you need to create links using action('HomeController#index') to have the locale follow you to the next link. Linking to /about will remove any language currently selected.