[WIP]IBX-9631: Implement parser fetching content fields from expression

src/bundle/Resources/config/services/utils.yaml

@@ -6,3 +6,13 @@ services:
 
     Ibexa\AdminUi\Util\:
         resource: "../../../../lib/Util"
+
+    Ibexa\AdminUi\Util\ContentTypeFieldsExpressionParserInterface:
+        alias: Ibexa\AdminUi\Util\ContentTypeFieldsExpressionParser
+
+    Ibexa\AdminUi\Util\ContentTypeFieldsExpressionParser: ~
+
+    Ibexa\AdminUi\Util\ContentTypeFieldsExtractorInterface:
+        alias: Ibexa\AdminUi\Util\ContentTypeFieldsExtractor
+
+    Ibexa\AdminUi\Util\ContentTypeFieldsExtractor: ~

src/lib/Util/ContentTypeFieldsExpressionDoctrineLexer.php

@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * @copyright Copyright (C) Ibexa AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace Ibexa\AdminUi\Util;
+
+use Doctrine\Common\Lexer\AbstractLexer;
+
+/**
+ * @extends AbstractLexer<ContentTypeFieldsExpressionDoctrineLexer::T_*, string>
+ */
+final class ContentTypeFieldsExpressionDoctrineLexer extends AbstractLexer
+{
+    public const T_LBRACE = 1;
+    public const T_RBRACE = 2;
+    public const T_COMMA = 3;
+    public const T_SLASH = 4;
+    public const T_WILDCARD = 5;
+    public const T_IDENTIFIER = 6;
+
+    /**
+     * @return list<string>
+     */
+    protected function getCatchablePatterns(): array
+    {
+        return [
+            '[a-zA-Z_][a-zA-Z0-9_-]*',
+            '\*',
+            '[\{\},\/]',
+        ];
+    }
+
+    /**
+     * @return list<string>
+     */
+    protected function getNonCatchablePatterns(): array
+    {
+        return [
+            '\s+',
+        ];
+    }
+
+    /**
+     * @param string $value
+     */
+    protected function getType(&$value): int
+    {
+        if ($value === '{') {
+            return self::T_LBRACE;
+        }
+
+        if ($value === '}') {
+            return self::T_RBRACE;
+        }
+
+        if ($value === ',') {
+            return self::T_COMMA;
+        }
+
+        if ($value === '/') {
+            return self::T_SLASH;
+        }
+
+        if ($value === '*') {
+            return self::T_WILDCARD;
+        }
+
+        return self::T_IDENTIFIER;
+    }
+}

src/lib/Util/ContentTypeFieldsExpressionParser.php

@@ -0,0 +1,173 @@
+<?php
+
+/**
+ * @copyright Copyright (C) Ibexa AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace Ibexa\AdminUi\Util;
+
+use RuntimeException;
+
+final class ContentTypeFieldsExpressionParser implements ContentTypeFieldsExpressionParserInterface
+{
+    private ContentTypeFieldsExpressionDoctrineLexer $lexer;
+
+    public function __construct()
+    {
+        $this->lexer = new ContentTypeFieldsExpressionDoctrineLexer();
+    }
+
+    public function parseExpression(string $expression): array
+    {
+        // Content type group can be omitted therefore we need to know how many parts are there
+        $slashCount = substr_count($expression, '/');
+
+        $this->lexer->setInput($expression);
+        $this->lexer->moveNext();
+
+        $groupTokens = null; // Content type groups are optional
+        $contentTypeTokens = null;
+        $fieldTokens = null;
+
+        while ($this->lexer->lookahead !== null) {
+            $this->lexer->moveNext();
+
+            if ($slashCount === 2) {
+                $groupTokens = $this->parseSection();
+                $this->expectSlash();
+                $contentTypeTokens = $this->parseSection();
+                $this->expectSlash();
+                $fieldTokens = $this->parseSection();
+            } elseif ($slashCount === 1) {
+                $groupTokens = null;
+                $contentTypeTokens = $this->parseSection();
+                $this->expectSlash();
+                $fieldTokens = $this->parseSection();
+            } else {
+                throw new RuntimeException('Invalid expression, expected one or two T_SLASH delimiters.');
+            }
+        }
+
+        $parsedTokens = [
+            $groupTokens,
+            $contentTypeTokens,
+            $fieldTokens,
+        ];
+
+        if (array_filter($parsedTokens) === []) {
+            throw new RuntimeException('Choosing every possible content type field is not allowed.');
+        }
+
+        return $parsedTokens;
+    }
+
+    /**
+     * @return non-empty-list<string>|null
+     */
+    private function parseSection(): ?array
+    {
+        $items = [];
+
+        if ($this->lexer->token === null) {
+            throw new RuntimeException('A token inside a section cannot be empty.');
+        }
+
+        // Multiple elements between braces
+        if ($this->lexer->token->isA(ContentTypeFieldsExpressionDoctrineLexer::T_LBRACE)) {
+            $items[] = $this->getTokenFromInsideBracket();
+
+            while ($this->lexer->token->isA(ContentTypeFieldsExpressionDoctrineLexer::T_COMMA)) {
+                $items[] = $this->getTokenFromInsideBracket();
+            }
+
+            if (!$this->lexer->token->isA(ContentTypeFieldsExpressionDoctrineLexer::T_RBRACE)) {
+                throw new RuntimeException('Expected T_RBRACE to close the list.');
+            }
+
+            $this->lexer->moveNext();
+        } else {
+            // Otherwise, expect a single identifier or wildcard.
+            $token = $this->expectIdentifierOrWildcard();
+
+            if ($token === null) {
+                return null;
+            }
+
+            $items[] = $token;
+        }
+
+        return $items;
+    }
+
+    private function getTokenFromInsideBracket(): string
+    {
+        $this->lexer->moveNext();
+
+        $token = $this->expectIdentifierOrWildcard();
+        if ($token === null) {
+            throw new RuntimeException('Wildcards cannot be mixed with identifiers inside the expression.');
+        }
+
+        return $token;
+    }
+
+    /**
+     * @throws \RuntimeException
+     */
+    private function expectSlash(): void
+    {
+        if ($this->lexer->token === null) {
+            throw new RuntimeException(
+                sprintf(
+                    'Expected token of type "%s" but got "null"',
+                    ContentTypeFieldsExpressionDoctrineLexer::T_SLASH,
+                ),
+            );
+        }
+
+        if (!$this->lexer->token->isA(ContentTypeFieldsExpressionDoctrineLexer::T_SLASH)) {
+            throw new RuntimeException(
+                sprintf(
+                    'Expected token of type "%s" but got "%s"',
+                    ContentTypeFieldsExpressionDoctrineLexer::T_SLASH,
+                    $this->lexer->token->type,
+                ),
+            );
+        }
+
+        $this->lexer->moveNext();
+    }
+
+    private function expectIdentifierOrWildcard(): ?string
+    {
+        if ($this->lexer->token === null) {
+            throw new RuntimeException(
+                sprintf(
+                    'Expected token of type "%s" but got "null"',
+                    ContentTypeFieldsExpressionDoctrineLexer::T_SLASH,
+                ),
+            );
+        }
+
+        if (!in_array(
+            $this->lexer->token->type,
+            [
+                ContentTypeFieldsExpressionDoctrineLexer::T_IDENTIFIER,
+                ContentTypeFieldsExpressionDoctrineLexer::T_WILDCARD,
+            ],
+            true,
+        )) {
+            throw new RuntimeException('Expected an identifier or wildcard.');
+        }
+
+        $value = $this->lexer->token->isA(ContentTypeFieldsExpressionDoctrineLexer::T_WILDCARD)
+            ? null
+            : $this->lexer->token->value;
+
+        $this->lexer->moveNext();
+
+        return $value;
+    }
+}

src/lib/Util/ContentTypeFieldsExpressionParserInterface.php

@@ -0,0 +1,19 @@
+<?php
+
+/**
+ * @copyright Copyright (C) Ibexa AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace Ibexa\AdminUi\Util;
+
+interface ContentTypeFieldsExpressionParserInterface
+{
+    /**
+     * @return array{non-empty-list<string>|null, non-empty-list<string>|null, non-empty-list<string>|null}
+     *
+     * @throws \RuntimeException
+     */
+    public function parseExpression(string $expression): array;
+}