<?php

namespace App\Http\Controllers;

use App\Models\Permission;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class PermissionController extends Controller
{
    /**
     * 权限列表(按分组)
     */
    public function index(Request $request)
    {
        $query = Permission::query();

        if ($request->filled('group')) {
            $query->where('group_name', $request->group);
        }

        if ($request->filled('keyword')) {
            $query->where('name', 'like', "%{$request->keyword}%");
        }

        $permissions = $query->orderBy('group_name')->orderBy('sort')->get();

        // 按分组组织
        $grouped = $permissions->groupBy('group_name')->map(fn($items) => $items->map(fn($p) => [
            'id' => $p->id,
            'name' => $p->name,
            'code' => $p->slug,
            'description' => $p->description,
        ]));

        // 扁平列表
        $list = $permissions->map(fn($p) => [
            'id' => $p->id,
            'name' => $p->name,
            'code' => $p->slug,
            'group' => $p->group_name,
            'description' => $p->description,
        ]);

        return response()->json([
            'code' => 200,
            'data' => [
                'list' => $list,
                'grouped' => $grouped,
            ],
            'message' => 'success',
        ]);
    }

    /**
     * 创建权限
     */
    public function store(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'name' => 'required|string|max:255',
            'code' => 'required|string|max:100|unique:permissions,slug|regex:/^[a-z.]+$/',
            'group' => 'required|string|max:100',
            'description' => 'nullable|string|max:500',
            'sort' => 'nullable|integer|min:0',
        ]);

        if ($validator->fails()) {
            return response()->json(['code' => 422, 'message' => '验证失败', 'errors' => $validator->errors()], 422);
        }

        $permission = Permission::create([
            'name' => $request->name,
            'slug' => $request->code,
            'group_name' => $request->group,
            'description' => $request->description,
            'sort' => $request->sort ?? 0,
        ]);

        return response()->json([
            'code' => 200,
            'data' => $permission,
            'message' => '权限创建成功',
        ]);
    }

    /**
     * 更新权限
     */
    public function update(Request $request, string $id)
    {
        $permission = Permission::find($id);
        if (!$permission) {
            return response()->json(['code' => 404, 'message' => '权限不存在'], 404);
        }

        $validator = Validator::make($request->all(), [
            'name' => 'sometimes|string|max:255',
            'group' => 'sometimes|string|max:100',
            'description' => 'nullable|string|max:500',
            'sort' => 'nullable|integer|min:0',
        ]);

        if ($validator->fails()) {
            return response()->json(['code' => 422, 'message' => '验证失败', 'errors' => $validator->errors()], 422);
        }

        $permission->update($request->only(['name', 'group_name', 'description', 'sort']));

        return response()->json([
            'code' => 200,
            'data' => $permission,
            'message' => '权限更新成功',
        ]);
    }

    /**
     * 删除权限
     */
    public function destroy(string $id)
    {
        $permission = Permission::find($id);
        if (!$permission) {
            return response()->json(['code' => 404, 'message' => '权限不存在'], 404);
        }

        $permission->roles()->detach();
        $permission->delete();

        return response()->json(['code' => 200, 'message' => '删除成功']);
    }

    /**
     * 获取所有分组
     */
    public function groups()
    {
        $groups = Permission::select('group_name')
            ->distinct()
            ->whereNotNull('group_name')
            ->orderBy('group_name')
            ->pluck('group_name');

        return response()->json([
            'code' => 200,
            'data' => $groups,
            'message' => 'success',
        ]);
    }

    /**
     * 批量创建权限
     */
    public function batchStore(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'permissions' => 'required|array',
            'permissions.*.name' => 'required|string',
            'permissions.*.code' => 'required|string',
            'permissions.*.group' => 'required|string',
        ]);

        if ($validator->fails()) {
            return response()->json(['code' => 422, 'message' => '验证失败', 'errors' => $validator->errors()], 422);
        }

        $created = 0;
        foreach ($request->permissions as $perm) {
            if (!Permission::where('slug', $perm['code'])->exists()) {
                Permission::create([
                    'name' => $perm['name'],
                    'slug' => $perm['code'],
                    'group_name' => $perm['group'],
                    'description' => $perm['description'] ?? null,
                    'sort' => $perm['sort'] ?? 0,
                ]);
                $created++;
            }
        }

        return response()->json([
            'code' => 200,
            'data' => ['created' => $created],
            'message' => "成功创建 {$created} 个权限",
        ]);
    }
}