import Koa from "koa";
import { UserState } from "../login";
import { sendError } from "../route/error_handler";

export enum Permission {
    // ========
    // not implemented
    // admin only
    /** remove document */
    // removeContent = 'removeContent',

    /** upload document */
    // uploadContent = 'uploadContent',

    /** modify document except base path, filename, content_hash. but admin can modify all. */
    // modifyContent = 'modifyContent',

    /** add tag into document */
    // addTagContent = 'addTagContent',
    /** remove tag from document */
    // removeTagContent = 'removeTagContent',
    /** ModifyTagInDoc */
    ModifyTag = "ModifyTag",

    /** find documents with query */
    // findAllContent = 'findAllContent',
    /** find one document. */
    // findOneContent = 'findOneContent',
    /** view content*/
    // viewContent = 'viewContent',
    QueryContent = "QueryContent",

    /** modify description about the one tag. */
    modifyTagDesc = "ModifyTagDesc",
}

export const createPermissionCheckMiddleware =
    (...permissions: string[]) => async (ctx: Koa.ParameterizedContext<UserState>, next: Koa.Next) => {
        const user = ctx.state["user"];
        if (user.username === "admin") {
            return await next();
        }
        const user_permission = user.permission;
        // if permissions is not subset of user permission
        if (!permissions.map(p => user_permission.includes(p)).every(x => x)) {
            if (user.username === "") {
                return sendError(401, "you are guest. login needed.");
            } else return sendError(403, "do not have permission");
        }
        await next();
    };
export const AdminOnlyMiddleware = async (ctx: Koa.ParameterizedContext<UserState>, next: Koa.Next) => {
    const user = ctx.state["user"];
    if (user.username !== "admin") {
        return sendError(403, "admin only");
    }
    await next();
};