fix: tree & guide

app/Models/GuidePage.php

@@ -3,42 +3,26 @@
 namespace App\Models;
 
 use Illuminate\Database\Eloquent\Model;
-use SolutionForest\FilamentTree\Concern\ModelTree;
 
 class GuidePage extends Model
 {
-    use ModelTree;
-
     protected $fillable = [
         'guide_id',
-        'page_number',
         'title',
         'html_url',
-        'sort_order',
-        'parent_id',
         'options',
-        'branch_option',
     ];
 
     protected $casts = [
         'options' => 'array',
-        'parent_id' => 'int',
     ];
 
-    // filament-tree column name mapping
-    public function determineParentColumnName(): string
+    protected static function booted(): void
     {
-        return 'parent_id';
-    }
-
-    public function determineOrderColumnName(): string
-    {
-        return 'sort_order';
-    }
-
-    public function determineTitleColumnName(): string
-    {
-        return 'title';
+        static::deleting(function (GuidePage $page) {
+            // CASCADE on from_page_id is handled by FK, but incoming edges need cleanup
+            GuidePageEdge::where('to_page_id', $page->id)->delete();
+        });
     }
 
     public function guide()
@@ -46,13 +30,32 @@ class GuidePage extends Model
         return $this->belongsTo(Guide::class);
     }
 
-    public function branchChildren()
+    public function outgoingEdges()
     {
-        return $this->hasMany(self::class, 'parent_id')->orderBy('sort_order');
+        return $this->hasMany(GuidePageEdge::class, 'from_page_id')->orderBy('sort');
     }
 
-    public function parentPage()
+    public function incomingEdges()
     {
-        return $this->belongsTo(self::class, 'parent_id');
+        return $this->hasMany(GuidePageEdge::class, 'to_page_id');
     }
+
+    public function nextPages()
+    {
+        return $this->belongsToMany(self::class, 'guide_page_edges', 'from_page_id', 'to_page_id')
+            ->withPivot('label', 'sort')
+            ->orderByPivot('sort');
+    }
+
+    public function previousPages()
+    {
+        return $this->belongsToMany(self::class, 'guide_page_edges', 'to_page_id', 'from_page_id')
+            ->withPivot('label', 'sort');
+    }
+
+    public function isEntry(): bool
+    {
+        return !$this->incomingEdges()->exists();
+    }
+
 }