Improve implementation

bakame-php · Mar 26, 2024 · ecfca43 · ecfca43
1 parent 0c37300
commit ecfca43
Showing 1 changed file with 24 additions and 15 deletions.
diff --git a/src/Base32/Base32.php b/src/Base32/Base32.php
@@ -102,20 +102,13 @@ public function decode(string $encoded, bool $strict = false): string
             $encoded = strtoupper($encoded);
         }
 
-        $remainder = strlen($encoded) % 8;
-        if (0 !== $remainder) {
-            if ($strict) {
-                throw new RuntimeException('The encoded data length is invalid.');
-            }
-
-            $encoded .= str_repeat($padding, $remainder);
-        }
-
         $inside = rtrim($encoded, $padding);
         $end = substr($encoded, strlen($inside));
-        $endLength = strlen($end);
-        if ($strict && 0 !== $endLength && 1 !== $endLength && 3 !== $endLength && 4 !== $endLength && 6 !== $endLength) {
-            throw new RuntimeException('The encoded data ends with an invalid padding sequence length.');
+        if ($strict) {
+            $endLength = strlen($end);
+            if (0 !== $endLength && 1 !== $endLength && 3 !== $endLength && 4 !== $endLength && 6 !== $endLength) {
+                throw new RuntimeException('The encoded data ends with an invalid padding sequence length.');
+            }
         }
 
         if (false !== strpos($inside, $padding)) {
@@ -126,18 +119,34 @@ public function decode(string $encoded, bool $strict = false): string
             $encoded = str_replace($padding, '', $inside).$end;
         }
 
+        $remainder = strlen($encoded) % 8;
+        if (0 !== $remainder) {
+            if ($strict) {
+                throw new RuntimeException('The encoded data length is invalid.');
+            }
+
+            for ($index = 0; $index < $remainder; $index++) {
+                $encoded .= $padding;
+            }
+        }
+
         $chars = [];
-        foreach (str_split($alphabet) as $offset => $char) {
-            $chars[$char] = $offset;
+        for ($index = 0; $index < self::ALPHABET_SIZE; $index++) {
+            $chars[$alphabet[$index]] = $index;
         }
         $chars[$padding] = 0;
+
         $offset = 0;
         $bitLen = 5;
         $length = strlen($encoded);
         $decoded = '';
 
         do {
-            $val ??= $chars[$encoded[$offset]] ?? -1;
+            if (!isset($val)) {
+                $index = $encoded[$offset];
+                $val = array_key_exists($index, $chars) ? $chars[$index] : -1;
+            }
+
             if (-1 === $val) {
                 if ($strict) {
                     throw new RuntimeException('The encoded data contains characters unknown to the base32 alphabet.');