/**
 * Permissions guard.
 * @file 管理端权限校验守卫
 * @module guards/permissions.guard
 * @author zhxiao1124
 */

import { CanActivate, ExecutionContext, ForbiddenException, Injectable } from "@nestjs/common";
import { Reflector } from "@nestjs/core";
import { Request } from "express";
import { REQUIRED_PERMISSIONS_METADATA } from "@app/decorators/require-permissions.decorator";
import { AdminUserRecord } from "@src/admin/admin.types";
import { AdminService } from "@src/admin/admin.service";

@Injectable()
export class PermissionsGuard implements CanActivate {
    constructor(
        private readonly reflector: Reflector,
        private readonly adminService: AdminService,
    ) {}

    async canActivate(context: ExecutionContext): Promise<boolean> {
        const required = this.reflector.getAllAndOverride<string[]>(REQUIRED_PERMISSIONS_METADATA, [context.getHandler(), context.getClass()]) ?? [];

        if (required.length === 0) {
            return true;
        }

        const request = context.switchToHttp().getRequest<Request & { adminUser?: AdminUserRecord }>();
        const adminUser = request.adminUser;

        if (!adminUser) {
            throw new ForbiddenException("No permission");
        }

        if (adminUser.isSuperAdmin) {
            return true;
        }

        const permissions = await this.adminService.getPermissionCodesForAdmin(adminUser.id);
        const allowed = required.every((permission) => permissions.includes(permission));

        if (!allowed) {
            throw new ForbiddenException("No permission");
        }

        return true;
    }
}