feat: FontSuggest – ähnliche Schriftnamen für unbekannte Schriften (W5)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Integrations/Divi/Design/FontSuggest.php

@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Integrations\Divi\Design;
+
+defined('ABSPATH') || exit;
+
+/**
+ * Names that resemble an unknown font name, for the hint of a validation error (ruling W5). Case-insensitive;
+ * ranked: the same name in another case, a name that starts with it, one that contains it, then a small
+ * Levenshtein distance (at most max(3, length / 3)). Within a rank the closer, then the shorter, then the
+ * alphabetically first name wins, so the order is deterministic. Pure PHP.
+ */
+final class FontSuggest
+{
+    /**
+     * @param list<string> $names
+     * @return list<string> At most $limit names.
+     */
+    public static function similar(string $name, array $names, int $limit = 5): array
+    {
+        $needle = mb_strtolower(trim($name));
+        if ($needle === '' || $limit < 1) {
+            return [];
+        }
+        $maxDistance = max(3, intdiv(mb_strlen($needle), 3));
+        $ranked = [];
+        foreach (array_unique($names) as $candidate) {
+            $lower = mb_strtolower($candidate);
+            $distance = levenshtein($needle, $lower);
+            $rank = match (true) {
+                $lower === $needle => 0,
+                str_starts_with($lower, $needle) => 1,
+                str_contains($lower, $needle) => 2,
+                $distance <= $maxDistance => 3,
+                default => null,
+            };
+            if ($rank !== null) {
+                $ranked[] = [$rank, $distance, mb_strlen($candidate), $candidate];
+            }
+        }
+        usort($ranked, static fn (array $a, array $b): int => $a[0] <=> $b[0] ?: $a[1] <=> $b[1] ?: $a[2] <=> $b[2]
+            ?: strcmp($a[3], $b[3]));
+
+        return array_slice(array_column($ranked, 3), 0, $limit);
+    }
+}

tests/Unit/Integrations/Divi/Design/FontSuggestTest.php

@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace LIT\MCP\Tests\Unit\Integrations\Divi\Design;
+
+use LIT\MCP\Integrations\Divi\Design\FontSuggest;
+use PHPUnit\Framework\TestCase;
+
+final class FontSuggestTest extends TestCase
+{
+    private const NAMES = [
+        'Roboto', 'Roboto Condensed', 'Roboto Slab', 'Open Sans', 'Open Sans Condensed', 'Lato', 'Lora', 'Arial',
+        'Source Sans 3', 'Playfair Display', 'Helvetica', 'Georgia',
+    ];
+
+    public function testTheSameNameInAnotherCaseComesFirst(): void
+    {
+        self::assertSame(
+            ['Open Sans', 'Open Sans Condensed'],
+            FontSuggest::similar('open sans', self::NAMES, 2)
+        );
+        self::assertSame('Lato', FontSuggest::similar('LATO', self::NAMES)[0]);
+    }
+
+    public function testRanksPrefixBeforeSubstringBeforeASmallDistance(): void
+    {
+        $names = ['Big Roboto', 'Rubik', 'Roboto Slab', 'Roboot', 'Robot'];
+
+        self::assertSame(
+            ['Roboto Slab', 'Big Roboto', 'Robot', 'Roboot'],
+            FontSuggest::similar('roboto', $names)
+        );
+    }
+
+    public function testATypoIsFoundByDistanceButUnrelatedNamesAreNot(): void
+    {
+        self::assertSame(['Open Sans'], FontSuggest::similar('Opne Sans', self::NAMES));
+        self::assertSame(['Playfair Display'], FontSuggest::similar('Playfair Displey', self::NAMES));
+        self::assertSame([], FontSuggest::similar('Comic Sans', ['Arial', 'Georgia', 'Helvetica']));
+    }
+
+    public function testTheLimitCutsTheListAndTheOrderIsStable(): void
+    {
+        $first = FontSuggest::similar('Roboto', self::NAMES, 2);
+
+        self::assertSame(['Roboto', 'Roboto Slab'], $first);
+        self::assertSame($first, FontSuggest::similar('Roboto', array_reverse(self::NAMES), 2));
+        self::assertSame(['Roboto', 'Roboto Slab', 'Roboto Condensed'], FontSuggest::similar('Roboto', self::NAMES, 5));
+        self::assertCount(5, FontSuggest::similar('o', self::NAMES));
+    }
+
+    public function testTiesAreBrokenByLengthThenAlphabet(): void
+    {
+        self::assertSame(['Aab', 'Aac', 'Aaaa'], FontSuggest::similar('aa', ['Aaaa', 'Aac', 'Aab']));
+    }
+
+    public function testEdgeCases(): void
+    {
+        self::assertSame([], FontSuggest::similar('', self::NAMES));
+        self::assertSame([], FontSuggest::similar('   ', self::NAMES));
+        self::assertSame([], FontSuggest::similar('Lato', self::NAMES, 0));
+        self::assertSame([], FontSuggest::similar('Lato', []));
+        self::assertSame(['Lato'], FontSuggest::similar(' lato ', ['Lato', 'Lato']), 'trimmed, duplicates once');
+        self::assertSame(['Fjalla Önö'], FontSuggest::similar('FJALLA ÖNÖ', ['Fjalla Önö']));
+    }
+}