TM-SGNL-iOS/SignalServiceKit/Messages/Interactions/GroupUpdateSource.swift
TeleMessage developers dde0620daf initial commit
2025-05-03 12:28:28 -07:00

117 lines
4 KiB
Swift

//
// Copyright 2024 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//
import Foundation
public import LibSignalClient
public indirect enum GroupUpdateSource {
/// No source found.
case unknown
/// Source known to be the local user. The original source
/// cannot itself be localUser or unknown.
case localUser(originalSource: GroupUpdateSource)
/// Legacy update (pre-GV2) with only an e164.
case legacyE164(E164)
/// Standard case. Most updates come from an ACI.
case aci(Aci)
/// A user who was invited by PNI rejected the invite.
///
/// This case will refer to the ``GroupsProtoGroupChangeActionsDeletePendingMemberAction``,
/// when the pending member in question is identified by a PNI.
///
/// This is, at the time of writing, the only case in which the best
/// identifier we have for the group update source is a PNI.
case rejectedInviteToPni(Pni)
/// If future updates introduce additional cases in which a PNI is the
/// best/only identifier for the group update source, add them here. These
/// cases are rare exceptions to the rule, so we prefer to enumerate them so
/// as to make it easier for callers to understand exactly when they might
/// be dealing with a PNI.
}
extension GroupUpdateSource {
public func serviceIdUnsafeForLocalUserComparison() -> ServiceId? {
switch self {
case .unknown:
return nil
case .legacyE164:
return nil
case .aci(let aci):
return aci
case .rejectedInviteToPni(let pni):
return pni
case .localUser(let originalSource):
return originalSource.serviceIdUnsafeForLocalUserComparison()
}
}
}
extension GroupUpdateSource: Equatable {}
extension TSInfoMessage {
// MARK: - Serialization
internal static func legacyGroupUpdateSource(
infoMessageUserInfoDict: [InfoMessageUserInfoKey: Any]?
) -> GroupUpdateSource {
guard let infoMessageUserInfoDict else {
return .unknown
}
// Legacy cases stored if they were known local users.
let isKnownLocalUser: () -> Bool = {
if let storedValue = infoMessageUserInfoDict[.legacyUpdaterKnownToBeLocalUser] as? Bool {
return storedValue
}
// Check for legacy persisted enum state.
if
let legacyPrecomputed = infoMessageUserInfoDict[.legacyGroupUpdateItems]
as? LegacyPersistableGroupUpdateItemsWrapper,
case let .inviteRemoved(_, wasLocalUser) = legacyPrecomputed.updateItems.first
{
return wasLocalUser
}
return false
}
guard let address = infoMessageUserInfoDict[.groupUpdateSourceLegacyAddress] as? SignalServiceAddress else {
return .unknown
}
if let aci = address.serviceId as? Aci {
if isKnownLocalUser() {
return .localUser(originalSource: .aci(aci))
}
return .aci(aci)
} else if let pni = address.serviceId as? Pni {
// When GroupUpdateSource was introduced, the _only_ way to have
// a Pni (and not an aci) be the source address was when the update
// came from someone invited by Pni rejecting that invitation.
// Maybe other cases got added in the future, but if they did they'd
// not use the legacy address storage, so if we find a legacy address
// with a Pni, it _must_ be from the pni invite rejection case.
if isKnownLocalUser() {
return .localUser(originalSource: .rejectedInviteToPni(pni))
} else {
return .rejectedInviteToPni(pni)
}
} else if let e164 = address.e164 {
if isKnownLocalUser() {
return .localUser(originalSource: .legacyE164(e164))
} else {
return .legacyE164(e164)
}
} else {
return .unknown
}
}
}