调整数据库表的单复数

app/Models/System/City.php

@@ -9,40 +9,35 @@ use Illuminate\Database\Eloquent\Relations\HasMany;
 class City extends Model
 {
     use ModelTrait;
-    protected $table = 'system_cities';
+    protected $table = 'system_city';
 
     protected $fillable = [
-        'parent_id',
-        'name',
+        'title',
         'code',
-        'pinyin',
-        'pinyin_short',
-        'level',
-        'sort',
-        'status',
-    ];
-
-    protected $casts = [
-        'parent_id' => 'integer',
-        'level' => 'integer',
-        'sort' => 'integer',
-        'status' => 'boolean',
+        'parent_code',
     ];
 
+    /**
+     * 子级城市
+     */
     public function children(): HasMany
     {
-        return $this->hasMany(City::class, 'parent_id')->orderBy('sort');
-    }
-
-    public function activeChildren(): HasMany
-    {
-        return $this->hasMany(City::class, 'parent_id')
-            ->where('status', true)
-            ->orderBy('sort');
+        return $this->hasMany(City::class, 'parent_code', 'code');
     }
 
+    /**
+     * 父级城市
+     */
     public function parent()
     {
-        return $this->belongsTo(City::class, 'parent_id');
+        return $this->belongsTo(City::class, 'parent_code', 'code');
+    }
+
+    /**
+     * 判断是否是顶级城市（省/直辖市/自治区）
+     */
+    public function isTopLevel(): bool
+    {
+        return empty($this->parent_code);
     }
 }