internal linking

app/Support/FaviconResolver.php

@@ -0,0 +1,107 @@
+<?php
+
+namespace App\Support;
+
+use Illuminate\Http\Client\Response;
+use Illuminate\Support\Facades\Http;
+use Illuminate\Support\Str;
+
+/**
+ * Finds a real, working favicon/icon URL for a site. `{domain}/favicon.ico`
+ * is a guess, not a guarantee -- plenty of sites serve their icon from a
+ * hashed asset path, an SVG, or declare it only via a <link rel="icon">
+ * tag. This tries progressively more reliable sources before giving up.
+ */
+class FaviconResolver
+{
+    public function resolve(string $siteUrl): ?string
+    {
+        return $this->fromWellKnownPath($siteUrl)
+            ?? $this->fromHtmlLinkTag($siteUrl)
+            ?? $this->fromGoogleFallback($siteUrl);
+    }
+
+    private function fromWellKnownPath(string $siteUrl): ?string
+    {
+        $candidate = rtrim($siteUrl, '/').'/favicon.ico';
+
+        return $this->isImage($candidate) ? $candidate : null;
+    }
+
+    private function fromHtmlLinkTag(string $siteUrl): ?string
+    {
+        $response = $this->safeGet($siteUrl);
+
+        if (! $response || ! $response->successful()) {
+            return null;
+        }
+
+        if (! preg_match_all(
+            '/<link\b[^>]*rel=["\'](?:shortcut icon|icon|apple-touch-icon)["\'][^>]*>/i',
+            $response->body(),
+            $tags
+        )) {
+            return null;
+        }
+
+        foreach ($tags[0] as $tag) {
+            if (! preg_match('/href=["\']([^"\']+)["\']/i', $tag, $hrefMatch)) {
+                continue;
+            }
+
+            $absolute = $this->toAbsoluteUrl($hrefMatch[1], $siteUrl);
+
+            if ($absolute && $this->isImage($absolute)) {
+                return $absolute;
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Google's favicon service resolves almost anything (it does its own
+     * multi-source lookup), making it a reliable last resort rather than
+     * leaving the tool with no logo at all.
+     */
+    private function fromGoogleFallback(string $siteUrl): string
+    {
+        return 'https://www.google.com/s2/favicons?sz=128&domain_url='.urlencode($siteUrl);
+    }
+
+    private function toAbsoluteUrl(string $href, string $base): ?string
+    {
+        if (Str::startsWith($href, ['http://', 'https://'])) {
+            return $href;
+        }
+
+        $parsed = parse_url($base);
+
+        if (! $parsed || ! isset($parsed['scheme'], $parsed['host'])) {
+            return null;
+        }
+
+        if (Str::startsWith($href, '//')) {
+            return "{$parsed['scheme']}:{$href}";
+        }
+
+        return "{$parsed['scheme']}://{$parsed['host']}/".ltrim($href, '/');
+    }
+
+    private function isImage(string $url): bool
+    {
+        $response = $this->safeGet($url);
+
+        return (bool) $response?->successful()
+            && str_starts_with((string) $response->header('Content-Type'), 'image/');
+    }
+
+    private function safeGet(string $url): ?Response
+    {
+        try {
+            return Http::timeout(6)->get($url);
+        } catch (\Throwable) {
+            return null;
+        }
+    }
+}