chat/src/app/utils/matrix.ts

import {
  EncryptedAttachmentInfo,
  decryptAttachment,
  encryptAttachment,
} from 'browser-encrypt-attachment';
import {
  MatrixClient,
  MatrixError,
  MatrixEvent,
  Room,
  RoomMember,
  UploadProgress,
  UploadResponse,
} from 'matrix-js-sdk';
import { IImageInfo, IThumbnailContent, IVideoInfo } from '../../types/matrix/common';
import { AccountDataEvent } from '../../types/matrix/accountData';

export const matchMxId = (id: string): RegExpMatchArray | null =>
  id.match(/^([@!$+#])(\S+):(\S+)$/);

export const validMxId = (id: string): boolean => !!matchMxId(id);

export const getMxIdServer = (userId: string): string | undefined => matchMxId(userId)?.[3];

export const getMxIdLocalPart = (userId: string): string | undefined => matchMxId(userId)?.[2];

export const isUserId = (id: string): boolean => validMxId(id) && id.startsWith('@');

export const isRoomId = (id: string): boolean => validMxId(id) && id.startsWith('!');

export const isRoomAlias = (id: string): boolean => validMxId(id) && id.startsWith('#');

export const parseMatrixToUrl = (url: string): [string | undefined, string | undefined] => {
  const href = decodeURIComponent(url);

  const match = href.match(/^https?:\/\/matrix.to\/#\/([@!$+#]\S+:[^\\?|^\s|^\\/]+)(\?(via=\S+))?/);
  if (!match) return [undefined, undefined];
  const [, g1AsMxId, , g3AsVia] = match;
  return [g1AsMxId, g3AsVia];
};

export const getCanonicalAliasRoomId = (mx: MatrixClient, alias: string): string | undefined =>
  mx.getRooms()?.find((room) => room.getCanonicalAlias() === alias)?.roomId;

export const getCanonicalAliasOrRoomId = (mx: MatrixClient, roomId: string): string =>
  mx.getRoom(roomId)?.getCanonicalAlias() || roomId;

export const getImageInfo = (img: HTMLImageElement, fileOrBlob: File | Blob): IImageInfo => {
  const info: IImageInfo = {};
  info.w = img.width;
  info.h = img.height;
  info.mimetype = fileOrBlob.type;
  info.size = fileOrBlob.size;
  return info;
};

export const getVideoInfo = (video: HTMLVideoElement, fileOrBlob: File | Blob): IVideoInfo => {
  const info: IVideoInfo = {};
  info.duration = Number.isNaN(video.duration) ? undefined : Math.floor(video.duration * 1000);
  info.w = video.videoWidth;
  info.h = video.videoHeight;
  info.mimetype = fileOrBlob.type;
  info.size = fileOrBlob.size;
  return info;
};

export const getThumbnailContent = (thumbnailInfo: {
  thumbnail: File | Blob;
  encInfo: EncryptedAttachmentInfo | undefined;
  mxc: string;
  width: number;
  height: number;
}): IThumbnailContent => {
  const { thumbnail, encInfo, mxc, width, height } = thumbnailInfo;

  const content: IThumbnailContent = {
    thumbnail_info: {
      mimetype: thumbnail.type,
      size: thumbnail.size,
      w: width,
      h: height,
    },
  };
  if (encInfo) {
    content.thumbnail_file = {
      ...encInfo,
      url: mxc,
    };
  } else {
    content.thumbnail_url = mxc;
  }
  return content;
};

export const encryptFile = async (
  file: File | Blob
): Promise<{
  encInfo: EncryptedAttachmentInfo;
  file: File;
  originalFile: File | Blob;
}> => {
  const dataBuffer = await file.arrayBuffer();
  const encryptedAttachment = await encryptAttachment(dataBuffer);
  const encFile = new File([encryptedAttachment.data], file.name, {
    type: file.type,
  });
  return {
    encInfo: encryptedAttachment.info,
    file: encFile,
    originalFile: file,
  };
};

export const decryptFile = async (
  dataBuffer: ArrayBuffer,
  type: string,
  encInfo: EncryptedAttachmentInfo
): Promise<Blob> => {
  const dataArray = await decryptAttachment(dataBuffer, encInfo);
  const blob = new Blob([dataArray], { type });
  return blob;
};

export type TUploadContent = File | Blob;

export type ContentUploadOptions = {
  name?: string;
  fileType?: string;
  hideFilename?: boolean;
  onPromise?: (promise: Promise<UploadResponse>) => void;
  onProgress?: (progress: UploadProgress) => void;
  onSuccess: (mxc: string) => void;
  onError: (error: MatrixError) => void;
};

export const uploadContent = async (
  mx: MatrixClient,
  file: TUploadContent,
  options: ContentUploadOptions
) => {
  const { name, fileType, hideFilename, onProgress, onPromise, onSuccess, onError } = options;

  const uploadPromise = mx.uploadContent(file, {
    name,
    type: fileType,
    includeFilename: !hideFilename,
    progressHandler: onProgress,
  });
  onPromise?.(uploadPromise);
  try {
    const data = await uploadPromise;
    const mxc = data.content_uri;
    if (mxc) onSuccess(mxc);
    else onError(new MatrixError(data));
  } catch (e: any) {
    const error = typeof e?.message === 'string' ? e.message : undefined;
    const errcode = typeof e?.name === 'string' ? e.message : undefined;
    onError(new MatrixError({ error, errcode }));
  }
};

export const matrixEventByRecency = (m1: MatrixEvent, m2: MatrixEvent) => m2.getTs() - m1.getTs();

export const factoryEventSentBy = (senderId: string) => (ev: MatrixEvent) =>
  ev.getSender() === senderId;

export const eventWithShortcode = (ev: MatrixEvent) =>
  typeof ev.getContent().shortcode === 'string';

export const getDMRoomFor = (mx: MatrixClient, userId: string): Room | undefined => {
  const dmLikeRooms = mx
    .getRooms()
    .filter((room) => mx.isRoomEncrypted(room.roomId) && room.getMembers().length <= 2);

  return dmLikeRooms.find((room) => room.getMember(userId));
};

export const guessDmRoomUserId = (room: Room, myUserId: string): string => {
  const getOldestMember = (members: RoomMember[]): RoomMember | undefined => {
    let oldestMemberTs: number | undefined;
    let oldestMember: RoomMember | undefined;

    const pickOldestMember = (member: RoomMember) => {
      if (member.userId === myUserId) return;

      if (
        oldestMemberTs === undefined ||
        (member.events.member && member.events.member.getTs() < oldestMemberTs)
      ) {
        oldestMember = member;
        oldestMemberTs = member.events.member?.getTs();
      }
    };

    members.forEach(pickOldestMember);

    return oldestMember;
  };

  // Pick the joined user who's been here longest (and isn't us),
  const member = getOldestMember(room.getJoinedMembers());
  if (member) return member.userId;

  // if there are no joined members other than us, use the oldest member
  const member1 = getOldestMember(room.currentState.getMembers());
  return member1?.userId ?? myUserId;
};

export const addRoomIdToMDirect = async (
  mx: MatrixClient,
  roomId: string,
  userId: string
): Promise<void> => {
  const mDirectsEvent = mx.getAccountData(AccountDataEvent.Direct);
  const userIdToRoomIds: Record<string, string[]> = mDirectsEvent?.getContent() ?? {};

  // remove it from the lists of any others users
  // (it can only be a DM room for one person)
  Object.keys(userIdToRoomIds).forEach((targetUserId) => {
    const roomIds = userIdToRoomIds[targetUserId];

    if (targetUserId !== userId) {
      const indexOfRoomId = roomIds.indexOf(roomId);
      if (indexOfRoomId > -1) {
        roomIds.splice(indexOfRoomId, 1);
      }
    }
  });

  const roomIds = userIdToRoomIds[userId] || [];
  if (roomIds.indexOf(roomId) === -1) {
    roomIds.push(roomId);
  }
  userIdToRoomIds[userId] = roomIds;

  await mx.setAccountData(AccountDataEvent.Direct, userIdToRoomIds);
};

export const removeRoomIdFromMDirect = async (mx: MatrixClient, roomId: string): Promise<void> => {
  const mDirectsEvent = mx.getAccountData(AccountDataEvent.Direct);
  const userIdToRoomIds: Record<string, string[]> = mDirectsEvent?.getContent() ?? {};

  Object.keys(userIdToRoomIds).forEach((targetUserId) => {
    const roomIds = userIdToRoomIds[targetUserId];
    const indexOfRoomId = roomIds.indexOf(roomId);
    if (indexOfRoomId > -1) {
      roomIds.splice(indexOfRoomId, 1);
    }
  });

  await mx.setAccountData(AccountDataEvent.Direct, userIdToRoomIds);
};