refactor: list command parsing

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

lib/Client/Protocol/Command/ListCommand.php

@@ -4,6 +4,7 @@ declare(strict_types=1);
 
 namespace KTXM\ProviderImap\Client\Protocol\Command;
 
+use KTXM\ProviderImap\Client\Protocol\Parser\ListResponseParser;
 use KTXM\ProviderImap\Client\Protocol\Parser\StatusResponseParser;
 use Generator;
 use KTXM\ProviderImap\Client\ImapException;
@@ -24,6 +25,7 @@ final class ListCommand implements CommandInterface
 {
     private readonly ListSelectionOptions $selectionOptions;
     private readonly ListReturnOptions $returnOptions;
+    private readonly ListResponseParser $listResponseParser;
     private readonly StatusResponseParser $statusResponseParser;
 
     public function __construct(
@@ -34,6 +36,7 @@ final class ListCommand implements CommandInterface
     ) {
         $this->selectionOptions = $selectionOptions ?? ListSelectionOptions::none();
         $this->returnOptions = $returnOptions ?? ListReturnOptions::none();
+        $this->listResponseParser = new ListResponseParser();
         $this->statusResponseParser = new StatusResponseParser();
     }
 
@@ -82,7 +85,7 @@ final class ListCommand implements CommandInterface
         if (!$this->returnOptions->hasStatus()) {
             foreach ($responses as $response) {
                 if ($response instanceof UntaggedResponse && $response->label() === 'LIST') {
-                    yield $this->parseMailbox($response->payload());
+                    yield $this->listResponseParser->parse($response->payload());
                     continue;
                 }
 
@@ -103,7 +106,7 @@ final class ListCommand implements CommandInterface
 
         foreach ($responses as $response) {
             if ($response instanceof UntaggedResponse && $response->label() === 'LIST') {
-                $mailbox = $this->parseMailbox($response->payload());
+                $mailbox = $this->listResponseParser->parse($response->payload());
                 $mailboxes[$mailbox->name()] = $this->applyStatus(
                     $mailbox,
                     $statuses[$mailbox->name()] ?? [],
@@ -138,30 +141,6 @@ final class ListCommand implements CommandInterface
         throw new ImapException('LIST did not receive a tagged completion response.');
     }
 
-    private function parseMailbox(string $payload): Mailbox
-    {
-        $payload = trim($payload);
-        $offset = 0;
-
-        $attributesToken = $this->readToken($payload, $offset);
-        $delimiterToken = $this->readToken($payload, $offset);
-        $nameToken = $this->readToken($payload, $offset);
-
-        if ($attributesToken === null || $delimiterToken === null || $nameToken === null) {
-            throw new ImapException('Unable to parse LIST response payload: ' . $payload);
-        }
-
-        $attributeString = trim($attributesToken, '() ');
-        $attributes = $attributeString === '' || strtoupper($attributeString) === 'NIL'
-            ? []
-            : array_map('strtoupper', preg_split('/\s+/', $attributeString) ?: []);
-
-        $delimiter = $this->decodeAtom($delimiterToken);
-        $name = $this->decodeMailboxName($nameToken);
-
-        return new Mailbox($name, $delimiter, $attributes);
-    }
-
     /**
      * @param array<string, int> $status
      */
@@ -180,83 +159,6 @@ final class ListCommand implements CommandInterface
         );
     }
 
-    private function readToken(string $payload, int &$offset): ?string
-    {
-        $length = strlen($payload);
-
-        while ($offset < $length && ctype_space($payload[$offset])) {
-            $offset++;
-        }
-
-        if ($offset >= $length) {
-            return null;
-        }
-
-        if ($payload[$offset] === '(') {
-            $end = strpos($payload, ')', $offset);
-
-            if ($end === false) {
-                throw new ImapException('Unterminated LIST attribute block: ' . $payload);
-            }
-
-            $token = substr($payload, $offset, $end - $offset + 1);
-            $offset = $end + 1;
-
-            return $token;
-        }
-
-        if ($payload[$offset] === '"') {
-            $start = $offset;
-            $offset++;
-
-            while ($offset < $length) {
-                if ($payload[$offset] === '\\') {
-                    $offset += 2;
-                    continue;
-                }
-
-                if ($payload[$offset] === '"') {
-                    $offset++;
-                    return substr($payload, $start, $offset - $start);
-                }
-
-                $offset++;
-            }
-
-            throw new ImapException('Unterminated quoted LIST token: ' . $payload);
-        }
-
-        $start = $offset;
-        while ($offset < $length && !ctype_space($payload[$offset])) {
-            $offset++;
-        }
-
-        return substr($payload, $start, $offset - $start);
-    }
-
-    private function decodeAtom(string $value): ?string
-    {
-        $value = trim($value);
-
-        if (strtoupper($value) === 'NIL') {
-            return null;
-        }
-
-        if (str_starts_with($value, '"') && str_ends_with($value, '"')) {
-            return stripcslashes(substr($value, 1, -1));
-        }
-
-        return $value;
-    }
-
-    private function decodeMailboxName(string $value): string
-    {
-        $name = $this->decodeAtom($value);
-
-        // LIST may advertise the root mailbox as an empty quoted string.
-        return $name ?? '';
-    }
-
     private function quote(string $value): string
     {
         return '"' . addcslashes($value, "\\\"") . '"';

lib/Client/Protocol/Parser/ListResponseParser.php

@@ -0,0 +1,116 @@
+<?php
+
+declare(strict_types=1);
+
+namespace KTXM\ProviderImap\Client\Protocol\Parser;
+
+use KTXM\ProviderImap\Client\ImapException;
+use KTXM\ProviderImap\Client\Mailbox;
+
+/**
+ * Decodes an individual LIST response payload into a mailbox.
+ */
+final class ListResponseParser
+{
+    public function parse(string $payload): Mailbox
+    {
+        $payload = trim($payload);
+        $offset = 0;
+
+        $attributesToken = $this->readToken($payload, $offset);
+        $delimiterToken = $this->readToken($payload, $offset);
+        $nameToken = $this->readToken($payload, $offset);
+
+        if ($attributesToken === null || $delimiterToken === null || $nameToken === null) {
+            throw new ImapException('Unable to parse LIST response payload: ' . $payload);
+        }
+
+        $attributeString = trim($attributesToken, '() ');
+        $attributes = $attributeString === '' || strtoupper($attributeString) === 'NIL'
+            ? []
+            : array_map('strtoupper', preg_split('/\s+/', $attributeString) ?: []);
+
+        $delimiter = $this->decodeAtom($delimiterToken);
+        $name = $this->decodeMailboxName($nameToken);
+
+        return new Mailbox($name, $delimiter, $attributes);
+    }
+
+    private function readToken(string $payload, int &$offset): ?string
+    {
+        $length = strlen($payload);
+
+        while ($offset < $length && ctype_space($payload[$offset])) {
+            $offset++;
+        }
+
+        if ($offset >= $length) {
+            return null;
+        }
+
+        if ($payload[$offset] === '(') {
+            $end = strpos($payload, ')', $offset);
+
+            if ($end === false) {
+                throw new ImapException('Unterminated LIST attribute block: ' . $payload);
+            }
+
+            $token = substr($payload, $offset, $end - $offset + 1);
+            $offset = $end + 1;
+
+            return $token;
+        }
+
+        if ($payload[$offset] === '"') {
+            $start = $offset;
+            $offset++;
+
+            while ($offset < $length) {
+                if ($payload[$offset] === '\\') {
+                    $offset += 2;
+                    continue;
+                }
+
+                if ($payload[$offset] === '"') {
+                    $offset++;
+                    return substr($payload, $start, $offset - $start);
+                }
+
+                $offset++;
+            }
+
+            throw new ImapException('Unterminated quoted LIST token: ' . $payload);
+        }
+
+        $start = $offset;
+        while ($offset < $length && !ctype_space($payload[$offset])) {
+            $offset++;
+        }
+
+        return substr($payload, $start, $offset - $start);
+    }
+
+    private function decodeAtom(string $value): ?string
+    {
+        $value = trim($value);
+
+        if (strtoupper($value) === 'NIL') {
+            return null;
+        }
+
+        if (str_starts_with($value, '"') && str_ends_with($value, '"')) {
+            return stripcslashes(substr($value, 1, -1));
+        }
+
+        return $value;
+    }
+
+    private function decodeMailboxName(string $value): string
+    {
+        $name = $this->decodeAtom($value);
+
+        // LIST may advertise the root mailbox as an empty quoted string.
+        return $name ?? '';
+    }
+
+}