Files
mautrix-telegram/pkg/connector/media/transfer.go
T
2025-06-27 20:03:37 -07:00

419 lines
14 KiB
Go

// mautrix-telegram - A Matrix-Telegram puppeting bridge.
// Copyright (C) 2025 Sumner Evans
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
package media
import (
"bytes"
"context"
"fmt"
"io"
"net/http"
"github.com/rs/zerolog"
"maunium.net/go/mautrix/bridgev2"
"maunium.net/go/mautrix/event"
"maunium.net/go/mautrix/id"
"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/downloader"
"go.mau.fi/mautrix-telegram/pkg/gotd/tg"
"go.mau.fi/util/gnuzip"
"go.mau.fi/mautrix-telegram/pkg/connector/ids"
"go.mau.fi/mautrix-telegram/pkg/connector/store"
)
type dimensionable interface {
GetW() int
GetH() int
}
func getLargestPhotoSize(sizes []tg.PhotoSizeClass) (width, height, fileSize int, largest tg.PhotoSizeClass) {
if len(sizes) == 0 {
panic("cannot get largest size from empty list of sizes")
}
// FIXME this max size seems to be confusing bytes and dimensions.
for _, s := range sizes {
var currentSize int
switch size := s.(type) {
case *tg.PhotoSize:
currentSize = size.GetSize()
case *tg.PhotoCachedSize:
currentSize = max(size.W, size.H, len(size.Bytes))
case *tg.PhotoSizeProgressive:
currentSize = max(size.W, size.H)
for _, sz := range size.Sizes {
currentSize = max(currentSize, sz)
}
case *tg.PhotoPathSize:
currentSize = len(size.GetBytes())
case *tg.PhotoStrippedSize:
currentSize = len(size.GetBytes())
}
if currentSize > fileSize {
fileSize = currentSize
largest = s
if d, ok := s.(dimensionable); ok {
width = d.GetW()
height = d.GetH()
}
}
}
return
}
// getLocationID converts a Telegram [tg.Document],
// [tg.InputDocumentFileLocation], [tg.InputPeerPhotoFileLocation],
// [tg.InputFileLocation], or [tg.InputPhotoFileLocation] into a [LocationID]
// for use in the telegram_file table.
func getLocationID(loc any) (locID store.TelegramFileLocationID) {
var id string
switch location := loc.(type) {
case *tg.Document:
id = fmt.Sprintf("%d", location.ID)
case *tg.InputDocumentFileLocation:
id = fmt.Sprintf("%d-%s", location.ID, location.ThumbSize)
case *tg.InputPhotoFileLocation:
id = fmt.Sprintf("%d-%s", location.ID, location.ThumbSize)
case *tg.InputFileLocation:
id = fmt.Sprintf("%d-%d", location.VolumeID, location.LocalID)
case *tg.InputPeerPhotoFileLocation:
id = fmt.Sprintf("%d", location.PhotoID)
default:
panic(fmt.Errorf("unknown location type %T", location))
}
return store.TelegramFileLocationID(id)
}
// Transferer is a utility for downloading media from Telegram and uploading it
// to Matrix.
type Transferer struct {
client downloader.Client
roomID id.RoomID
filename string
animatedStickerConfig *AnimatedStickerConfig
fileInfo event.FileInfo
}
type ReadyTransferer struct {
inner *Transferer
loc tg.InputFileLocationClass
}
// NewTransferer creates a new [Transferer] with the given [downloader.Client].
// The client is used to download the media from Telegram.
func NewTransferer(client downloader.Client) *Transferer {
return &Transferer{client: client}
}
// WithRoomID sets the room ID for the [Transferer].
func (t *Transferer) WithRoomID(roomID id.RoomID) *Transferer {
t.roomID = roomID
return t
}
// WithFilename sets the filename for the [Transferer].
func (t *Transferer) WithFilename(filename string) *Transferer {
t.filename = filename
return t
}
// WithStickerConfig sets the animated sticker config for the [Transferer].
func (t *Transferer) WithStickerConfig(cfg AnimatedStickerConfig) *Transferer {
t.animatedStickerConfig = &cfg
switch cfg.Target {
case "png":
t.fileInfo.MimeType = "image/png"
case "gif":
t.fileInfo.MimeType = "image/gif"
case "webp":
t.fileInfo.MimeType = "image/webp"
case "webm":
t.fileInfo.MimeType = "video/webm"
}
return t
}
func (t *Transferer) WithMIMEType(mimeType string) *Transferer {
t.fileInfo.MimeType = mimeType
return t
}
func (t *Transferer) WithThumbnail(uri id.ContentURIString, file *event.EncryptedFileInfo, info *event.FileInfo) *Transferer {
t.fileInfo.ThumbnailURL = uri
t.fileInfo.ThumbnailFile = file
t.fileInfo.ThumbnailInfo = info
return t
}
func (t *Transferer) WithVideo(attr *tg.DocumentAttributeVideo) *Transferer {
t.fileInfo.Width, t.fileInfo.Height = attr.W, attr.H
t.fileInfo.Duration = int(attr.Duration * 1000)
return t
}
func (t *Transferer) WithImageSize(attr *tg.DocumentAttributeImageSize) *Transferer {
t.fileInfo.Width, t.fileInfo.Height = attr.W, attr.H
return t
}
// WithDocument transforms a [Transferer] to a [ReadyTransferer] by setting the
// given document as the location that will be downloaded by the
// [ReadyTransferer].
func (t *Transferer) WithDocument(doc tg.DocumentClass, thumbnail bool) *ReadyTransferer {
document := doc.(*tg.Document)
documentFileLocation := tg.InputDocumentFileLocation{
ID: document.GetID(),
AccessHash: document.GetAccessHash(),
FileReference: document.GetFileReference(),
}
if thumbnail {
_, _, _, largestThumbnail := getLargestPhotoSize(document.Thumbs)
documentFileLocation.ThumbSize = largestThumbnail.GetType()
} else {
t.fileInfo.Size = int(document.Size)
if t.fileInfo.MimeType == "" {
t.fileInfo.MimeType = document.GetMimeType()
}
}
return &ReadyTransferer{t, &documentFileLocation}
}
// WithPhoto transforms a [Transferer] to a [ReadyTransferer] by setting the
// given photo as the location that will be downloaded by the
// [ReadyTransferer].
func (t *Transferer) WithPhoto(pc tg.PhotoClass) *ReadyTransferer {
photo := pc.(*tg.Photo)
var largest tg.PhotoSizeClass
t.fileInfo.Width, t.fileInfo.Height, t.fileInfo.Size, largest = getLargestPhotoSize(photo.GetSizes())
return &ReadyTransferer{
inner: t,
loc: &tg.InputPhotoFileLocation{
ID: photo.GetID(),
AccessHash: photo.GetAccessHash(),
FileReference: photo.GetFileReference(),
ThumbSize: largest.GetType(),
},
}
}
// WithUserPhoto transforms a [Transferer] to a [ReadyTransferer] by setting
// the given user's photo as the location that will be downloaded by the
// [ReadyTransferer].
func (t *Transferer) WithUserPhoto(ctx context.Context, store *store.ScopedStore, userID int64, photoID int64) (*ReadyTransferer, error) {
if accessHash, err := store.GetAccessHash(ctx, ids.PeerTypeUser, userID); err != nil {
return nil, fmt.Errorf("failed to get user access hash for %d: %w", userID, err)
} else {
return &ReadyTransferer{
inner: t,
loc: &tg.InputPeerPhotoFileLocation{
Peer: &tg.InputPeerUser{UserID: userID, AccessHash: accessHash},
PhotoID: photoID,
Big: true,
},
}, nil
}
}
// WithChannelPhoto transforms a [Transferer] to a [ReadyTransferer] by setting
// the given chat photo as the location that will be downloaded by the
// [ReadyTransferer].
func (t *Transferer) WithChannelPhoto(channelID, accessHash, photoID int64) *ReadyTransferer {
return &ReadyTransferer{
inner: t,
loc: &tg.InputPeerPhotoFileLocation{
Peer: &tg.InputPeerChannel{ChannelID: channelID, AccessHash: accessHash},
PhotoID: photoID,
Big: true,
},
}
}
// Transfer downloads the media from Telegram and uploads it to Matrix.
//
// If the file is already in the database, the MXC URI will be reused. The
// file's MXC URI will only be cached if the room ID is unset or if the room is
// not encrypted.
//
// If there is a sticker config on the [Transferer], this function converts
// animated stickers to the target format specified by the specified
// [AnimatedStickerConfig].
func (t *ReadyTransferer) Transfer(ctx context.Context, store *store.Container, intent bridgev2.MatrixAPI) (mxc id.ContentURIString, encryptedFileInfo *event.EncryptedFileInfo, outFileInfo *event.FileInfo, err error) {
locationID := getLocationID(t.loc)
log := zerolog.Ctx(ctx).With().
Str("component", "media_transfer").
Str("location_id", string(locationID)).
Logger()
ctx = log.WithContext(ctx)
log.Info().Msg("Transferring file from Telegram to Matrix")
if file, err := store.TelegramFile.GetByLocationID(ctx, locationID); err != nil {
return "", nil, nil, fmt.Errorf("failed to search for Telegram file by location ID: %w", err)
} else if file != nil {
t.inner.fileInfo.Size, t.inner.fileInfo.MimeType = file.Size, file.MIMEType
return file.MXC, nil, &t.inner.fileInfo, nil
}
var reader io.Reader
reader, t.inner.fileInfo.MimeType, t.inner.fileInfo.Size, err = t.Stream(ctx)
if err != nil {
return "", nil, nil, fmt.Errorf("downloading file failed: %w", err)
}
if t.inner.animatedStickerConfig != nil && t.inner.fileInfo.MimeType == "application/x-tgsticker" {
data, err := io.ReadAll(reader)
if err != nil {
return "", nil, nil, fmt.Errorf("reading sticker data failed: %w", err)
}
converted := t.inner.animatedStickerConfig.convert(ctx, data)
reader = converted.DataWriter
t.inner.fileInfo.MimeType = converted.MIMEType
t.inner.fileInfo.Width = converted.Width
t.inner.fileInfo.Height = converted.Height
t.inner.fileInfo.Size = converted.Size
if len(converted.ThumbnailData) > 0 {
thumbnailMXC, thumbnailFileInfo, err := intent.UploadMedia(ctx, t.inner.roomID, converted.ThumbnailData, t.inner.filename, converted.ThumbnailMIMEType)
if err != nil {
log.Err(err).Msg("failed to upload animated sticker thumbnail to Matrix")
} else {
t.inner = t.inner.WithThumbnail(thumbnailMXC, thumbnailFileInfo, &event.FileInfo{
MimeType: converted.ThumbnailMIMEType,
Width: converted.Width,
Height: converted.Height,
Size: len(converted.ThumbnailData),
})
}
}
}
mxc, encryptedFileInfo, err = intent.UploadMediaStream(ctx, t.inner.roomID, int64(t.inner.fileInfo.Size), false, func(file io.Writer) (*bridgev2.FileStreamResult, error) {
_, err := io.Copy(file, reader)
return &bridgev2.FileStreamResult{
FileName: t.inner.filename,
MimeType: t.inner.fileInfo.MimeType,
}, err
})
if err != nil {
return "", nil, nil, fmt.Errorf("failed to upload media to Matrix: %w", err)
}
// If it's an unencrypted file, cache the MXC URI corresponding to the
// location ID.
if len(mxc) > 0 {
file := store.TelegramFile.New()
file.LocationID = locationID
file.MXC = mxc
file.Size = t.inner.fileInfo.Size
file.MIMEType = t.inner.fileInfo.MimeType
if err = file.Insert(ctx); err != nil {
log.Err(err).Msg("failed to insert Telegram file into database")
}
}
return mxc, encryptedFileInfo, &t.inner.fileInfo, nil
}
// Stream streams the media from Telegram to an [io.Reader].
func (t *ReadyTransferer) Stream(ctx context.Context) (r io.Reader, mimeType string, fileSize int, err error) {
var storageFileTypeClass tg.StorageFileTypeClass
storageFileTypeClass, r, err = downloader.NewDownloader().WithPartSize(1024*1024).Download(t.inner.client, t.loc).StreamToReader(ctx)
if err != nil {
return nil, "", 0, err
}
if t.inner.fileInfo.MimeType == "" {
switch storageFileTypeClass.(type) {
case *tg.StorageFileJpeg:
t.inner.fileInfo.MimeType = "image/jpeg"
case *tg.StorageFileGif:
t.inner.fileInfo.MimeType = "image/gif"
case *tg.StorageFilePng:
t.inner.fileInfo.MimeType = "image/png"
case *tg.StorageFilePdf:
t.inner.fileInfo.MimeType = "application/pdf"
case *tg.StorageFileMp3:
t.inner.fileInfo.MimeType = "audio/mp3"
case *tg.StorageFileMov:
t.inner.fileInfo.MimeType = "video/quicktime"
case *tg.StorageFileMp4:
t.inner.fileInfo.MimeType = "video/mp4"
case *tg.StorageFileWebp:
t.inner.fileInfo.MimeType = "image/webp"
default:
// Just guess it's a JPEG. All documents should have specified the
// MIME type, and all photos are JPEG.
t.inner.fileInfo.MimeType = "image/jpeg"
}
}
if t.inner.animatedStickerConfig != nil {
data, err := io.ReadAll(r)
if err != nil {
return nil, "", 0, fmt.Errorf("failed to read animated sticker data: %w", err)
} else if detected := http.DetectContentType(data); detected == "application/x-tgsticker" || detected == "application/x-gzip" {
if unzipped, err := gnuzip.MaybeGUnzip(data); err != nil {
zerolog.Ctx(ctx).Err(err).Msg("failed to unzip animated sticker")
} else {
converted := t.inner.animatedStickerConfig.convert(ctx, unzipped)
t.inner.fileInfo.MimeType = converted.MIMEType
t.inner.fileInfo.Size = converted.Size
return converted.DataWriter, t.inner.fileInfo.MimeType, t.inner.fileInfo.Size, nil
}
}
return bytes.NewReader(data), t.inner.fileInfo.MimeType, t.inner.fileInfo.Size, nil
}
return r, t.inner.fileInfo.MimeType, t.inner.fileInfo.Size, nil
}
// DownloadBytes downloads the media from Telegram to a byte buffer.
func (t *ReadyTransferer) DownloadBytes(ctx context.Context) ([]byte, error) {
var buf bytes.Buffer
_, err := downloader.NewDownloader().Download(t.inner.client, t.loc).Stream(ctx, &buf)
return buf.Bytes(), err
}
// DirectDownloadURL returns the direct download URL for the media.
func (t *ReadyTransferer) DirectDownloadURL(ctx context.Context, loggedInUserID int64, portal *bridgev2.Portal, msgID int, thumbnail bool, telegramMediaID int64) (id.ContentURIString, *event.FileInfo, error) {
peerType, chatID, err := ids.ParsePortalID(portal.ID)
if err != nil {
return "", nil, err
}
mediaID, err := ids.DirectMediaInfo{
PeerType: peerType,
PeerID: chatID,
UserID: loggedInUserID,
MessageID: int64(msgID),
Thumbnail: thumbnail,
ID: telegramMediaID,
}.AsMediaID()
if err != nil {
return "", nil, err
}
mxc, err := portal.Bridge.Matrix.GenerateContentURI(ctx, mediaID)
if t.inner.fileInfo.MimeType == "" {
t.inner.fileInfo.MimeType = "image/jpeg"
}
if t.inner.fileInfo.MimeType == "application/x-tgsticker" {
t.inner.fileInfo.MimeType = "video/lottie+json"
}
return mxc, &t.inner.fileInfo, err
}