<?php
declare (strict_types=1);

namespace app\service;

use think\facade\Config;

class PermissionService
{
    /**
     * 获取所有权限配置
     */
    public static function getAllPermissions(): array
    {
        return Config::get('permission.permissions', []);
    }

    /**
     * 获取权限组配置
     */
    public static function getPermissionGroups(): array
    {
        return Config::get('permission.permission_groups', []);
    }

    /**
     * 根据权限组名获取权限配置
     */
    public static function getPermissionsByGroup($groupName): array
    {
        $groups = self::getPermissionGroups();
        return $groups[$groupName]['permissions'] ?? [];
    }

    /**
     * 验证权限格式
     */
    public static function validatePermissions($permissions): bool
    {
        if (!is_array($permissions)) {
            return false;
        }

        $allPermissions = self::getAllPermissions();
        
        foreach ($permissions as $controller => $actions) {
            // 检查控制器是否存在
            if (!isset($allPermissions[$controller])) {
                return false;
            }
            
            if (!is_array($actions)) {
                return false;
            }
            
            // 检查操作是否存在
            foreach ($actions as $action) {
                if (!isset($allPermissions[$controller]['actions'][$action])) {
                    return false;
                }
            }
        }
        
        return true;
    }

    /**
     * 格式化权限为树形结构（用于前端显示）
     */
    public static function formatPermissionsToTree(): array
    {
        $permissions = self::getAllPermissions();
        $tree = [];
        
        foreach ($permissions as $controller => $config) {
            $controllerNode = [
                'id' => $controller,
                'title' => $config['name'],
                'spread' => false,
                'children' => []
            ];
            
            foreach ($config['actions'] as $action => $actionName) {
                $controllerNode['children'][] = [
                    'id' => $controller . '_' . $action,
                    'title' => $actionName,
                    'controller' => $controller,
                    'action' => $action
                ];
            }
            
            $tree[] = $controllerNode;
        }
        
        return $tree;
    }

    /**
     * 将用户权限格式化为前端可用的格式
     */
    public static function formatUserPermissions($userPermissions): array
    {
        $formatted = [];
        
        if (!is_array($userPermissions)) {
            return $formatted;
        }
        
        foreach ($userPermissions as $controller => $actions) {
            if (is_array($actions)) {
                foreach ($actions as $action) {
                    $formatted[] = $controller . '_' . $action;
                }
            }
        }
        
        return $formatted;
    }

    /**
     * 将前端提交的权限格式转换为标准格式
     */
    public static function parsePermissionsFromFrontend($permissions): array
    {
        $parsed = [];
        
        if (!is_array($permissions)) {
            return $parsed;
        }
        
        foreach ($permissions as $permission) {
            if (strpos($permission, '_') !== false) {
                [$controller, $action] = explode('_', $permission, 2);
                
                if (!isset($parsed[$controller])) {
                    $parsed[$controller] = [];
                }
                
                if (!in_array($action, $parsed[$controller])) {
                    $parsed[$controller][] = $action;
                }
            }
        }
        
        return $parsed;
    }

    /**
     * 合并权限
     */
    public static function mergePermissions($permissions1, $permissions2): array
    {
        $merged = $permissions1;
        
        foreach ($permissions2 as $controller => $actions) {
            if (!isset($merged[$controller])) {
                $merged[$controller] = [];
            }
            
            $merged[$controller] = array_unique(array_merge($merged[$controller], $actions));
        }
        
        return $merged;
    }

    /**
     * 检查权限包含关系
     */
    public static function hasPermission($userPermissions, $controller, $action): bool
    {
        return isset($userPermissions[$controller]) && 
               is_array($userPermissions[$controller]) && 
               in_array($action, $userPermissions[$controller]);
    }

    /**
     * 获取用户所有可访问的控制器
     */
    public static function getUserAccessibleControllers($userPermissions): array
    {
        return array_keys($userPermissions);
    }

    /**
     * 获取控制器的所有可访问操作
     */
    public static function getControllerAccessibleActions($userPermissions, $controller): array
    {
        return $userPermissions[$controller] ?? [];
    }
}