feat: add Discord facade

app/Helpers/Discord.php

@@ -24,8 +24,11 @@ namespace App\Helpers;
 
 use App\Exceptions\AccountNotLinkedException;
 use App\User;
+use Carbon\Carbon;
 use Illuminate\Http\Client\RequestException;
+use Illuminate\Support\Collection;
 use Illuminate\Support\Facades\Auth;
+use Illuminate\Support\Facades\Cache;
 use Illuminate\Support\Facades\Crypt;
 use Illuminate\Support\Facades\Http;
 
@@ -50,7 +53,7 @@ class Discord
 
 
     public function __construct() {
-        if (!is_null($this->workingGuild)) {
+        if (isset($this->workingGuild)) {
             $this->setWorkingGuild(config('services.discord.home_guild'));
         }
     }
@@ -85,6 +88,47 @@ class Discord
        throw new AccountNotLinkedException('Specified website user has not linked their Discord account yet.');
     }
 
+    /**
+     * Obtains the current user's authentication info. Caches the data for the access_token's TTL, thus
+     * preventing unnecessary API requests.
+     *
+     * @return object Current user's authentication info (has no sensitive fields)
+     * @throws RequestException
+     */
+    public function getAuthorizationInfo(): object {
+
+        if (Cache::has($this->user->discord_user_id)) {
+            return unserialize(Cache::get($this->user->discord_user_id));
+        }
+        else {
+            $authInfo = (object) Http::withToken($this->user->discord_token)
+                ->get(config('services.discord.base_url') . '/oauth2/@me')
+                ->throw()
+                ->json();
+
+            Cache::put($this->user->discord_user_id, serialize($authInfo), Carbon::parse($authInfo->expires));
+
+            return $authInfo;
+        }
+    }
+
+
+    /**
+     * Checks if the user's token is close to expiring.
+     * Tokens should be refreshed the day before they expire.
+     *
+     * @return bool Whether the user's token needs to be refreshed
+     * @throws RequestException
+     */
+    public function needsRefresh(): bool {
+        return Carbon::parse($this->getAuthorizationInfo()->expires)->diffInDays() == 1;
+    }
+
+
+
+    public function exchangeRefreshToken() {
+
+    }