Sumner Evans
78 lines
2.3 KiB
Go
78 lines
2.3 KiB
Go
package ids
|
|
|
|
import (
|
|
"encoding/binary"
|
|
"fmt"
|
|
|
|
"maunium.net/go/mautrix/bridgev2/networkid"
|
|
)
|
|
|
|
// DirectMediaInfo is the information that is encoded in the media ID when
|
|
// using direct media.
|
|
//
|
|
// The format of the media ID is as follows (each character represents a single
|
|
// byte, |'s added for clarity):
|
|
//
|
|
// v|p|cccccccc|mmmmmmmm|T|MMMMMMMM
|
|
//
|
|
// v (int8) = binary encoding format version. Should be 0.
|
|
// p (byte) = the peer type of the Telegram chat ID
|
|
// cccccccc (int64) = the Telegram chat ID (big endian)
|
|
// mmmmmmmm (int64) = the Telegram message ID (big endian)
|
|
// T (byte) = 0 or 1 depending on whether it's a thumbnail (optional)
|
|
// MMMMMMMM (int64) = the Telegram media ID (big endian) (optional)
|
|
type DirectMediaInfo struct {
|
|
PeerType PeerType
|
|
ChatID int64
|
|
MessageID int64
|
|
Thumbnail bool
|
|
TelegramMediaID int64
|
|
}
|
|
|
|
func (m DirectMediaInfo) AsMediaID() (networkid.MediaID, error) {
|
|
mediaID := []byte{
|
|
0x00, // Version
|
|
m.PeerType.AsByte(), // Peer Type
|
|
}
|
|
mediaID = binary.BigEndian.AppendUint64(mediaID, uint64(m.ChatID)) // Telegram Chat ID
|
|
mediaID = binary.BigEndian.AppendUint64(mediaID, uint64(m.MessageID)) // Telegram Message ID
|
|
if m.Thumbnail {
|
|
mediaID = append(mediaID, 0x01)
|
|
} else {
|
|
mediaID = append(mediaID, 0x00)
|
|
}
|
|
mediaID = binary.BigEndian.AppendUint64(mediaID, uint64(m.TelegramMediaID)) // Telegram Message ID
|
|
return mediaID, nil
|
|
}
|
|
|
|
func ParseDirectMediaInfo(mediaID networkid.MediaID) (info DirectMediaInfo, err error) {
|
|
if len(mediaID) == 0 {
|
|
err = fmt.Errorf("empty media ID")
|
|
return
|
|
}
|
|
if mediaID[0] != 0x00 {
|
|
err = fmt.Errorf("invalid version %d", mediaID[0])
|
|
return
|
|
}
|
|
|
|
// For compatibility with old media IDs that don't have the thumbnail flag
|
|
// and the Telegram media ID, we allow media IDs with 18, 19, or 27 bytes.
|
|
if len(mediaID) != 18 && len(mediaID) != 19 && len(mediaID) != 27 {
|
|
err = fmt.Errorf("invalid media ID")
|
|
return
|
|
}
|
|
info.PeerType, err = PeerTypeFromByte(mediaID[1])
|
|
if err != nil {
|
|
return
|
|
}
|
|
info.ChatID = int64(binary.BigEndian.Uint64(mediaID[2:]))
|
|
info.MessageID = int64(binary.BigEndian.Uint64(mediaID[10:]))
|
|
if len(mediaID) >= 19 {
|
|
info.Thumbnail = mediaID[18] == 1
|
|
}
|
|
if len(mediaID) >= 20 {
|
|
info.TelegramMediaID = int64(binary.BigEndian.Uint64(mediaID[19:]))
|
|
}
|
|
return
|
|
}
|