feat: 外链中转 /go——点击统计 + 拦截 + 隐藏真实链接

- redirects 表 + UrlRedirector：go_url() 站外链接改写为 /go/{hash}（确定性 hash、同 URL 复用、并发安全、缓存）
- /go/{hash} 302 跳转 + 点击计数 + 最后点击时间；停用状态 410（二次拦截）；后台「外链中转」资源可查看点击量/启停/删除
- 接入点：正文外链（渲染器统一改写）、评论正文自动链接（comment_body）、评论作者网址、友链（侧边栏+友链页）；站内/相对/mailto/tel/锚点不中转
- 测试 6 个（改写/计数/拦截/复用/渲染/评论正文）；README 补充

app/Blog/Controllers/GoController.php

@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Blog\Controllers;
+
+use App\Models\Redirect;
+
+class GoController
+{
+    /**
+     * 外链中转跳转：计数 + 302。停用的链接返回 410（可作二次拦截）。
+     */
+    public function show(string $hash)
+    {
+        $redirect = Redirect::query()->where('hash', $hash)->firstOrFail();
+
+        if (! $redirect->isActive()) {
+            abort(410);
+        }
+
+        $redirect->hit();
+
+        return redirect()->away($redirect->target_url, 302);
+    }
+}

app/Blog/Services/PostContentRenderer.php

@@ -46,7 +46,31 @@ class PostContentRenderer
         $html = app(\App\Blog\Support\PluginManager::class)->applyFilters('post.rendered', $html, $post);
 
         // 兜底：任何情况下不把裸 [paid] 标签输出到页面（如会员插件被停用时）
-        return preg_replace('/\[(\/?paid)\]/i', '', $html);
+        $html = preg_replace('/\[(\/?paid)\]/i', '', $html);
+
+        // 外链中转：站外链接改写为 /go/{hash}（点击统计/拦截）
+        return $this->rewriteExternalLinks($html);
+    }
+
+    /**
+     * 把正文里的站外 <a href> 改写为 /go 中转地址（站内/相对/锚点/mailto 不变）。
+     */
+    private function rewriteExternalLinks(string $html): string
+    {
+        return preg_replace_callback(
+            '/<a\s+([^>]*?href=["\'])([^"\']+)(["\'][^>]*)>(.*?)<\/a>/is',
+            function (array $m): string {
+                $url = html_entity_decode(trim($m[2]));
+                $go = go_url($url);
+
+                if ($go === $url) {
+                    return $m[0];
+                }
+
+                return '<a '.$m[1].e($go).$m[3].'>'.$m[4].'</a>';
+            },
+            $html
+        );
     }
 
     /**

app/Blog/Services/UrlRedirector.php

@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Blog\Services;
+
+use App\Models\Redirect;
+use Illuminate\Database\UniqueConstraintViolationException;
+use Illuminate\Support\Facades\Cache;
+
+/**
+ * 外链中转：把站外链接改写为 /go/{hash}，用于点击统计、二次拦截与未来广告位。
+ * 站内链接、相对路径、mailto/tel/锚点不中转。
+ */
+class UrlRedirector
+{
+    public function goUrl(string $url): string
+    {
+        $url = trim((string) $url);
+
+        if (! $this->isExternal($url)) {
+            return $url;
+        }
+
+        return route('go.show', $this->hashFor($url));
+    }
+
+    public function isExternal(string $url): bool
+    {
+        if (! preg_match('#^https?://#i', $url)) {
+            return false;
+        }
+
+        $host = parse_url($url, PHP_URL_HOST);
+
+        if (! $host) {
+            return false;
+        }
+
+        $internalHost = parse_url((string) config('app.url'), PHP_URL_HOST);
+
+        return strcasecmp($host, (string) $internalHost) !== 0;
+    }
+
+    /**
+     * 取 URL 对应的短 hash（确定性：同一 URL 复用同一条记录，并发安全）。
+     */
+    public function hashFor(string $url): string
+    {
+        return Cache::remember('go.hash.'.md5($url), now()->addDay(), function () use ($url) {
+            $hash = substr(hash('sha256', $url), 0, 10);
+
+            for ($i = 0; $i < 3; $i++) {
+                try {
+                    Redirect::create(['hash' => $hash, 'target_url' => $url]);
+
+                    return $hash;
+                } catch (UniqueConstraintViolationException) {
+                    $existing = Redirect::where('target_url', $url)->first();
+
+                    if ($existing) {
+                        return $existing->hash;
+                    }
+
+                    $hash = substr(hash('sha256', $url.$i), 0, 10);
+                }
+            }
+
+            return $hash;
+        });
+    }
+}

app/Filament/Resources/RedirectResource.php

@@ -0,0 +1,90 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources;
+
+use App\Filament\Resources\RedirectResource\Pages\ListRedirects;
+use App\Models\Redirect;
+use BackedEnum;
+use Filament\Actions\Action;
+use Filament\Actions\DeleteAction;
+use Filament\Resources\Resource;
+use Filament\Schemas\Schema;
+use Filament\Support\Icons\Heroicon;
+use Filament\Tables\Columns\TextColumn;
+use Filament\Tables\Table;
+
+class RedirectResource extends Resource
+{
+    protected static \UnitEnum|string|null $navigationGroup = '管理';
+
+    protected static ?string $model = Redirect::class;
+
+    protected static string|BackedEnum|null $navigationIcon = Heroicon::OutlinedArrowUturnRight;
+
+    protected static ?string $navigationLabel = '外链中转';
+
+    protected static ?string $pluralModelLabel = '外链中转';
+
+    public static function form(Schema $schema): Schema
+    {
+        return $schema;
+    }
+
+    public static function table(Table $table): Table
+    {
+        return $table
+            ->columns([
+                TextColumn::make('hash')
+                    ->label('短码')
+                    ->badge()
+                    ->color('gray'),
+                TextColumn::make('target_url')
+                    ->label('目标地址')
+                    ->limit(50)
+                    ->copyable()
+                    ->searchable(),
+                TextColumn::make('clicks')
+                    ->label('点击量')
+                    ->numeric()
+                    ->sortable(),
+                TextColumn::make('status')
+                    ->label('状态')
+                    ->badge()
+                    ->formatStateUsing(fn ($state) => $state === 'active' ? '启用' : '停用')
+                    ->color(fn ($state) => $state === 'active' ? 'success' : 'danger'),
+                TextColumn::make('last_clicked_at')
+                    ->label('最后点击')
+                    ->dateTime('Y-m-d H:i')
+                    ->placeholder('—')
+                    ->sortable(),
+                TextColumn::make('created_at')
+                    ->label('创建时间')
+                    ->dateTime('Y-m-d H:i')
+                    ->toggleable(isToggledHiddenByDefault: true),
+            ])
+            ->filters([
+                \Filament\Tables\Filters\SelectFilter::make('status')
+                    ->label('状态')
+                    ->options(['active' => '启用', 'disabled' => '停用']),
+            ], \Filament\Tables\Enums\FiltersLayout::AboveContent)
+            ->recordActions([
+                Action::make('toggle')
+                    ->label(fn (Redirect $record) => $record->isActive() ? '停用' : '启用')
+                    ->color(fn (Redirect $record) => $record->isActive() ? 'danger' : 'success')
+                    ->action(fn (Redirect $record) => $record->update(['status' => $record->isActive() ? 'disabled' : 'active'])),
+                DeleteAction::make(),
+            ])
+            ->recordUrl(null)
+            ->recordAction(null)
+            ->defaultSort('clicks', 'desc');
+    }
+
+    public static function getPages(): array
+    {
+        return [
+            'index' => ListRedirects::route('/'),
+        ];
+    }
+}

app/Filament/Resources/RedirectResource/Pages/ListRedirects.php

@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Filament\Resources\RedirectResource\Pages;
+
+use App\Filament\Resources\RedirectResource;
+use Filament\Resources\Pages\ListRecords;
+
+class ListRedirects extends ListRecords
+{
+    protected static string $resource = RedirectResource::class;
+}

app/Models/Redirect.php

@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Redirect extends Model
+{
+    protected $fillable = [
+        'hash', 'target_url', 'clicks', 'status', 'last_clicked_at',
+    ];
+
+    protected $casts = [
+        'last_clicked_at' => 'datetime',
+    ];
+
+    public function isActive(): bool
+    {
+        return $this->status === 'active';
+    }
+
+    public function hit(): void
+    {
+        $this->increment('clicks');
+        $this->update(['last_clicked_at' => now()]);
+    }
+}

app/Support/helpers.php

@@ -42,3 +42,31 @@ if (! function_exists('blog_setting')) {
         return \App\Models\Setting::get($key, $default);
     }
 }
+
+if (! function_exists('go_url')) {
+    /**
+     * 外链中转：站外链接改写为 /go/{hash}（点击统计/拦截），站内链接原样返回。
+     */
+    function go_url(string $url): string
+    {
+        return app(\App\Blog\Services\UrlRedirector::class)->goUrl($url);
+    }
+}
+
+if (! function_exists('comment_body')) {
+    /**
+     * 评论正文：转义 + 自动链接 URL（走 /go 中转，nofollow）。
+     */
+    function comment_body(string $text): string
+    {
+        $text = e($text);
+
+        $text = preg_replace_callback(
+            '#(https?://[^\s<>"\'()]+)#i',
+            fn (array $m) => '<a href="'.e(go_url($m[1])).'" target="_blank" rel="nofollow noopener">'.$m[1].'</a>',
+            $text
+        );
+
+        return nl2br($text);
+    }
+}