<?php

namespace App\Http\Controllers\API\Admin;

use App\Http\Controllers\Controller;
use App\Lib\Rs;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;

class SysPermissionController extends Controller
{
    /**
     * 获取权限列表
     */
    public function list(Request $request)
    {
        $params = $request->all();
        $page = $params['page'] ?? 1;
        $pageSize = $params['page_size'] ?? 10;
        $offset = ($page - 1) * $pageSize;

        $query = DB::table('sys_permission')
            ->where('deleted', 0);

        // 搜索条件
        if (!empty($params['permission_name'])) {
            $query->where('permission_name', 'like', '%' . $params['permission_name'] . '%');
        }
        if (!empty($params['permission_code'])) {
            $query->where('permission_code', 'like', '%' . $params['permission_code'] . '%');
        }
        if (isset($params['type']) && $params['type'] !== '') {
            $query->where('type', $params['type']);
        }
        if (isset($params['status']) && $params['status'] !== '') {
            $query->where('status', $params['status']);
        }

        $total = $query->count();
        $list = $query
            ->orderBy('sort', 'asc')
            ->orderBy('id', 'asc')
            ->offset($offset)
            ->limit($pageSize)
            ->get();

        return Rs::success([
            'list' => $list,
            'total' => $total
        ]);
    }

    /**
     * 保存权限
     */
    public function Save(Request $request)
    {
        $data = $request->all();

        // 验证必填字段
        if (empty($data['permission_name'])) {
            return Rs::error('权限名称不能为空');
        }
        if (empty($data['permission_code'])) {
            return Rs::error('权限编码不能为空');
        }
        if (empty($data['type'])) {
            return Rs::error('权限类型不能为空');
        }
        if (empty($data['parent_id'])) {
            $data['parent_id']=0;
        }
        // 检查权限编码是否已存在
        $exists = DB::table('sys_permission')
            ->where('permission_code', $data['permission_code'])
            ->where('deleted', 0);

        if (isset($data['id']) && $data['id'] > 0) {
            $exists->where('id', '<>', $data['id']);
        }

        if ($exists->exists()) {
            return Rs::error('权限编码已存在');
        }

        try {
            if (isset($data['id']) && $data['id'] > 0) {
                // 更新
                $id = $data['id'];
                unset($data['id']);
                $data['update_time'] = date('Y-m-d H:i:s');
                DB::table('sys_permission')
                    ->where('id', $id)
                    ->update($data);
            } else {
                // 新增
                $data['create_time'] = date('Y-m-d H:i:s');
                $data['update_time'] = date('Y-m-d H:i:s');
                $data['deleted'] = 0;
                $id = DB::table('sys_permission')->insertGetId($data);
            }

            return Rs::success(['id' => $id]);
        } catch (\Exception $e) {
            return Rs::error('保存失败：' . $e->getMessage());
        }
    }

    /**
     * 删除权限
     */
    public function Delete(Request $request)
    {
        $id = $request->input('id');
        if (empty($id)) {
            return Rs::error('ID不能为空');
        }

        try {
            // 检查是否有子权限
            $hasChildren = DB::table('sys_permission')
                ->where('parent_id', $id)
                ->where('deleted', 0)
                ->exists();

            if ($hasChildren) {
                return Rs::error('该权限下存在子权限，无法删除');
            }

            // 软删除
            DB::table('sys_permission')
                ->where('id', $id)
                ->update([
                    'deleted' => 1,
                    'update_time' => date('Y-m-d H:i:s')
                ]);

            // 删除角色权限关联
            DB::table('sys_role_permission')
                ->where('permission_id', $id)
                ->delete();

            return Rs::success();
        } catch (\Exception $e) {
            return Rs::error('删除失败：' . $e->getMessage());
        }
    }

    /**
     * 获取权限树
     */
    public function getPermissionTree()
    {
        $permissions = DB::table('sys_permission')
            ->where('deleted', 0)
            ->orderBy('sort', 'asc')
            ->orderBy('id', 'asc')
            ->get();

        $permissionTree = $this->buildPermissionTree($permissions);
        return Rs::success($permissionTree);
    }

    /**
     * 构建权限树
     */
    private function buildPermissionTree($permissions, $parentId = 0)
    {
        $tree = [];
        foreach ($permissions as $permission) {
            if ($permission->parent_id == $parentId) {
                $children = $this->buildPermissionTree($permissions, $permission->id);
                if (!empty($children)) {
                    $permission->children = $children;
                }
                $tree[] = $permission;
            }
        }
        return $tree;
    }

    /**
     * 获取所有权限（不分页，用于角色绑定）
     */
    public function getAllPermissions()
    {
        $permissions = DB::table('sys_permission')
            ->where('deleted', 0)
            ->orderBy('sort', 'asc')
            ->orderBy('id', 'asc')
            ->get();

        return Rs::success($permissions);
    }
}