refactor: generate unique alphabet for each model

red-explosion · Nov 27, 2023 · 9542f5e · 9542f5e
1 parent a25f07d
commit 9542f5e
Show file tree

Hide file tree

Showing 4 changed files with 41 additions and 30 deletions.
diff --git a/config/sqids.php b/config/sqids.php
@@ -4,19 +4,6 @@
 
 return [
 
-    /*
-    |--------------------------------------------------------------------------
-    | Alphabet
-    |--------------------------------------------------------------------------
-    |
-    | This option controls the default "alphabet" used for generating sqids.
-    | The characters and numbers listed below will be included. You must
-    | have at least 3 unique characters or numbers.
-    |
-    */
-
-    'alphabet' => 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789',
-
     /*
     |--------------------------------------------------------------------------
     | Length

diff --git a/src/Config.php b/src/Config.php
@@ -6,8 +6,6 @@
 
 class Config
 {
-    protected static string $defaultAlphabet = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
-
     protected static int $defaultMinLength = 10;
 
     protected static array $defaultBlacklist = [];
@@ -20,13 +18,7 @@ class Config
 
     public static function alphabet(): string
     {
-        $alphabet = config(key: 'sqids.alphabet', default: static::$defaultAlphabet);
-
-        if (!$alphabet || !is_string(value: $alphabet)) {
-            return static::$defaultAlphabet;
-        }
-
-        return $alphabet;
+        return 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
     }
 
     public static function minLength(): int

diff --git a/src/HasSqids.php b/src/HasSqids.php
@@ -59,6 +59,6 @@ public static function keyFromSqid(string $sqid): ?int
             return null;
         }
 
-        return Sqids::decodeId(id: $sqid)[0] ?? null;
+        return Sqids::decodeId(model: __CLASS__, id: $sqid)[0] ?? null;
     }
 }
diff --git a/src/Sqids.php b/src/Sqids.php
@@ -17,7 +17,7 @@ public static function forModel(Model $model): string
 
         $prefix = static::prefixForModel(model: $model::class);
         $separator = $prefix ? Config::separator() : null;
-        $sqid = static::encodeId(id: $id);
+        $sqid = static::encodeId(model: $model::class, id: $id);
 
         return "{$prefix}{$separator}{$sqid}";
     }
@@ -46,22 +46,54 @@ public static function prefixForModel(string $model): ?string
         };
     }
 
-    public static function encodeId(int $id): string
+    public static function encodeId(string $model, int $id): string
     {
-        return static::encoder()->encode(numbers: [$id]);
+        return static::encoder(model: $model)->encode(numbers: [$id]);
     }
 
-    public static function decodeId(string $id): array
+    public static function decodeId(string $model, string $id): array
     {
-        return static::encoder()->decode(id: $id);
+        return static::encoder(model: $model)->decode(id: $id);
     }
 
-    public static function encoder(): SqidsCore
+    public static function encoder(string $model): SqidsCore
     {
+        $model = mb_strtolower(string: class_basename($model));
+
         return new SqidsCore(
-            alphabet: Config::alphabet(),
+            alphabet: static::alphabetForModel(model: $model),
             minLength: Config::minLength(),
             blocklist: Config::blacklist(),
         );
     }
+
+    public static function alphabetForModel(string $model): string
+    {
+        $alphabet = Config::alphabet();
+        $modelLength = mb_strlen(string: $model);
+
+        if (!$modelLength) {
+            return Config::alphabet();
+        }
+
+        $alphabetArray = static::multiByteSplit(string: Config::alphabet());
+        $modelArray = static::multiByteSplit(string: $model);
+
+        for ($i = mb_strlen($alphabet) - 1, $v = 0, $p = 0; $i > 0; $i--, $v++) {
+            $v %= $modelLength;
+            $p += $int = mb_ord($modelArray[$v], 'UTF-8');
+            $j = ($int + $v + $p) % $i;
+
+            $temp = $alphabetArray[$j];
+            $alphabetArray[$j] = $alphabetArray[$i];
+            $alphabetArray[$i] = $temp;
+        }
+
+        return implode(separator: '', array: $alphabetArray);
+    }
+
+    protected static function multiByteSplit(string $string): array
+    {
+        return preg_split(pattern: '/(?!^)(?=.)/u', subject: $string) ?: [];
+    }
 }