element-web/src/stores/ThreepidInviteStore.ts

/*
Copyright 2020 The Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import EventEmitter from "events";
import { ComponentClass } from "../@types/common";
import { UPDATE_EVENT } from "./AsyncStore";
import { base32, base64 } from "rfc4648";

// Dev note: the interface is split in two so we don't have to disable the
// linter across the whole project.
export interface IThreepidInviteWireFormat {
    email: string;
    signurl: string;
    room_name: string;
    room_avatar_url: string;
    inviter_name: string;

    // TODO: Figure out if these are ever populated
    guest_access_token?: string;
    guest_user_id?: string;
}

interface IPersistedThreepidInvite extends IThreepidInviteWireFormat {
    roomId: string;
}

export interface IThreepidInvite {
    id: string; // generated by us
    roomId: string;
    toEmail: string;
    signUrl: string;
    roomName: string;
    roomAvatarUrl: string;
    inviterName: string;
}

const STORAGE_PREFIX = "mx_threepid_invite_";

export default class ThreepidInviteStore extends EventEmitter {
    private static _instance: ThreepidInviteStore;

    public static get instance(): ThreepidInviteStore {
        if (!ThreepidInviteStore._instance) {
            ThreepidInviteStore._instance = new ThreepidInviteStore();
        }
        return ThreepidInviteStore._instance;
    }

    public storeInvite(roomId: string, wireInvite: IThreepidInviteWireFormat): IThreepidInvite {
        console.log("Storing invite: ", {roomId, ...wireInvite});
        const invite = <IPersistedThreepidInvite>{roomId, ...wireInvite};
        const id = this.generateIdOf(invite);
        localStorage.setItem(`${STORAGE_PREFIX}${id}`, JSON.stringify(invite));
        return this.translateInvite(invite);
    }

    public getInvites(): IThreepidInvite[] {
        const result: IThreepidInvite[] = [];
        for (let i = 0; i < localStorage.length; i++) {
            const keyName = localStorage.key(i);
            if (!keyName.startsWith(STORAGE_PREFIX)) continue;

            const persisted = JSON.parse(localStorage.getItem(keyName)) as IPersistedThreepidInvite;
            result.push(this.translateInvite(persisted));
        }
        return result;
    }

    // Currently Element can only handle one invite at a time, so handle that
    public pickBestInvite(): IThreepidInvite {
        return this.getInvites()[0];
    }

    public resolveInvite(invite: IThreepidInvite) {
        localStorage.removeItem(`${STORAGE_PREFIX}${invite.id}`);
    }

    private generateIdOf(persisted: IPersistedThreepidInvite): string {
        // Use a consistent "hash" to form an ID.
        return base32.stringify(Buffer.from(JSON.stringify(persisted)));
    }

    private translateInvite(persisted: IPersistedThreepidInvite): IThreepidInvite {
        return {
            id: this.generateIdOf(persisted),
            roomId: persisted.roomId,
            toEmail: persisted.email,
            signUrl: persisted.signurl,
            roomName: persisted.room_name,
            roomAvatarUrl: persisted.room_avatar_url,
            inviterName: persisted.inviter_name,
        };
    }
}