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

318 lines
12 KiB
Swift

//
// Copyright 2024 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
//
public enum GroupUpdateSpamReportingMetadata {
// This update contains information that can be reported as spam.
case reportable(serverGuid: String)
// This update is missing necessary information to report as spam.
// This could be because the information was dropped (as with the round trip to a backup)
// or the serverGuid is otherwise missing. This information being missing
// isn't a fatal error, it just means that no attempt will be made to record or report
// spam based on this group action.
case unreportable
// We can't report this update because it came from a group action (create, join, etc.)
// intiated locally by the user.
case createdByLocalAction
// These updates were initiated locally to update the group state.
// there's no metadata to associate with these updates for reporting purposes.
case learnedByLocallyInitatedRefresh
}
extension TSInfoMessage {
static func makeForGroupUpdate(
timestamp: UInt64,
spamReportingMetadata: GroupUpdateSpamReportingMetadata,
groupThread: TSGroupThread,
updateItems: [PersistableGroupUpdateItem]
) -> TSInfoMessage {
owsPrecondition(!updateItems.isEmpty)
var userInfoForNewMessage: [InfoMessageUserInfoKey: Any] = [:]
userInfoForNewMessage[.groupUpdateItems] = PersistableGroupUpdateItemsWrapper(updateItems)
let spamReportingServerGuid: String? = {
switch spamReportingMetadata {
case .reportable(serverGuid: let serverGuid):
return serverGuid
case .unreportable, .createdByLocalAction, .learnedByLocallyInitatedRefresh:
return nil
}
}()
let infoMessage = TSInfoMessage(
thread: groupThread,
timestamp: timestamp,
serverGuid: spamReportingServerGuid,
messageType: .typeGroupUpdate,
infoMessageUserInfo: userInfoForNewMessage
)
return infoMessage
}
func setGroupUpdateItemsWrapper(_ updateItemsWrapper: PersistableGroupUpdateItemsWrapper) {
setInfoMessageValue(updateItemsWrapper, forKey: .groupUpdateItems)
}
}
public extension TSInfoMessage {
enum GroupUpdateMetadata {
public struct UpdateMetadata {
public let source: GroupUpdateSource
/// Whether we determined, at the time we created this info message, that
/// the updater was the local user.
/// - Returns
/// `true` if we knew conclusively that the updater was the local user, and
/// `false` otherwise.
public let updaterWasLocalUser: Bool
}
public struct GroupModel {
public let groupModel: TSGroupModel
public let dmToken: DisappearingMessageToken?
}
/// For legacy group updates we persisted a pre-rendered string, rather than the details
/// to generate that string.
case legacyRawString(String)
// For some time after we would persist the group state before and after
// (or just the new group state) along with other optional metadata.
// This will be soon unused at write time, but can still be present
// in the database as there was no migration done.
case newGroup(GroupModel, updateMetadata: UpdateMetadata)
case modelDiff(old: GroupModel, new: GroupModel, updateMetadata: UpdateMetadata)
/// Modern group updates are precomputed into an enum and stored with all necessary metadata
/// strongly typed, whether its a new group or an update to an existing group.
/// Group state is NOT stored with these types.
case precomputed(PersistableGroupUpdateItemsWrapper)
/// This is not a group update.
case nonGroupUpdate
}
@objc
func groupUpdateDescription(transaction tx: SDSAnyReadTransaction) -> NSAttributedString {
let fallback = DisplayableGroupUpdateItem.genericUpdateByUnknownUser.localizedText
guard
let localIdentifiers: LocalIdentifiers = DependenciesBridge.shared.tsAccountManager
.localIdentifiers(tx: tx.asV2Read)
else {
return fallback
}
let updateItems: [DisplayableGroupUpdateItem]
switch groupUpdateMetadata(localIdentifiers: localIdentifiers) {
case .nonGroupUpdate:
return fallback
case .legacyRawString(let string):
return NSAttributedString(string: string)
case .newGroup, .modelDiff, .precomputed:
guard let items = buildGroupUpdateItems(
localIdentifiers: localIdentifiers,
tx: tx.asV2Read,
transformer: { builder, precomputedItems, tx in
return builder.displayableUpdateItemsForPrecomputed(
precomputedUpdateItems: precomputedItems,
localIdentifiers: localIdentifiers,
tx: tx
)
}
) else {
return fallback
}
updateItems = items
}
guard let firstUpdateItem = updateItems.first else {
owsFailBeta("Should never have an empty update items list!")
return NSAttributedString()
}
let initialString = NSMutableAttributedString(
attributedString: firstUpdateItem.localizedText
)
return updateItems.dropFirst().reduce(initialString) { partialResult, updateItem in
partialResult.append("\n")
partialResult.append(updateItem.localizedText)
return partialResult
}
}
func computedGroupUpdateItems(
localIdentifiers: LocalIdentifiers,
tx: SDSAnyReadTransaction
) -> [PersistableGroupUpdateItem]? {
switch groupUpdateMetadata(localIdentifiers: localIdentifiers) {
case .legacyRawString, .nonGroupUpdate:
return nil
case .newGroup, .modelDiff, .precomputed:
return buildGroupUpdateItems(
localIdentifiers: localIdentifiers,
tx: tx.asV2Read,
transformer: { _, items, _ in return items }
)
}
}
func displayableGroupUpdateItems(
localIdentifiers: LocalIdentifiers,
tx: SDSAnyReadTransaction
) -> [DisplayableGroupUpdateItem]? {
switch groupUpdateMetadata(localIdentifiers: localIdentifiers) {
case .legacyRawString, .nonGroupUpdate:
return nil
case .newGroup, .modelDiff, .precomputed:
guard let localIdentifiers = DependenciesBridge.shared.tsAccountManager.localIdentifiers(
tx: tx.asV2Read
) else {
owsFailDebug("Missing local identifiers!")
return nil
}
return buildGroupUpdateItems(
localIdentifiers: localIdentifiers,
tx: tx.asV2Read,
transformer: { builder, precomputedItems, tx in
return builder.displayableUpdateItemsForPrecomputed(
precomputedUpdateItems: precomputedItems,
localIdentifiers: localIdentifiers,
tx: tx
)
}
)
}
}
func groupUpdateMetadata(localIdentifiers: LocalIdentifiers) -> GroupUpdateMetadata {
if let precomputed = infoMessageUserInfo?[.groupUpdateItems] as? PersistableGroupUpdateItemsWrapper {
return .precomputed(precomputed)
} else if let legacyPrecomputed = infoMessageUserInfo?[.legacyGroupUpdateItems] as? LegacyPersistableGroupUpdateItemsWrapper {
let updateMetadata = self.persistedLegacyUpdateMetadata
// Convert the legacy items into new items.
let mappedItems: [PersistableGroupUpdateItem] = legacyPrecomputed
.updateItems
.compactMap { legacyItem in
return legacyItem.toNewItem(
updater: updateMetadata.source,
oldGroupModel: infoMessageUserInfo?[.oldGroupModel] as? TSGroupModel,
localIdentifiers: localIdentifiers
)
}
return .precomputed(.init(mappedItems))
} else if
let newGroupModel: TSGroupModel = infoMessageValue(forKey: .newGroupModel)
{
let updateMetadata = self.persistedLegacyUpdateMetadata
if let oldGroupModel: TSGroupModel = infoMessageValue(forKey: .oldGroupModel) {
return .modelDiff(
old: .init(
groupModel: oldGroupModel,
dmToken: infoMessageValue(forKey: .oldDisappearingMessageToken)
),
new: .init(
groupModel: newGroupModel,
dmToken: infoMessageValue(forKey: .newDisappearingMessageToken)
),
updateMetadata: updateMetadata
)
} else {
return .newGroup(
.init(
groupModel: newGroupModel,
dmToken: infoMessageValue(forKey: .newDisappearingMessageToken)
),
updateMetadata: updateMetadata
)
}
} else if let customMessage {
return .legacyRawString(customMessage)
} else {
if messageType == .typeGroupUpdate {
owsFailDebug("Group update should contain some metadata!")
}
return .nonGroupUpdate
}
}
private func buildGroupUpdateItems<T>(
localIdentifiers: LocalIdentifiers,
tx: DBReadTransaction,
transformer: (
_ builder: GroupUpdateItemBuilder,
_ precomputedItems: [PersistableGroupUpdateItem],
_ tx: DBReadTransaction
) -> [T]
) -> [T]? {
lazy var groupUpdateItemBuilder = GroupUpdateItemBuilderImpl(
contactsManager: GroupUpdateItemBuilderImpl.Wrappers.ContactsManager(
SSKEnvironment.shared.contactManagerRef
),
recipientDatabaseTable: DependenciesBridge.shared.recipientDatabaseTable
)
let precomputedItems: [PersistableGroupUpdateItem]
switch groupUpdateMetadata(localIdentifiers: localIdentifiers) {
case .nonGroupUpdate, .legacyRawString:
return nil
case .precomputed(let precomputedUpdateItems):
precomputedItems = precomputedUpdateItems.updateItems
case let .newGroup(newGroupModel, updateMetadata):
precomputedItems = groupUpdateItemBuilder.precomputedUpdateItemsForNewGroup(
newGroupModel: newGroupModel.groupModel,
newDisappearingMessageToken: newGroupModel.dmToken,
localIdentifiers: localIdentifiers,
groupUpdateSource: updateMetadata.source,
tx: tx
)
case let .modelDiff(oldGroupModel, newGroupModel, updateMetadata):
precomputedItems = groupUpdateItemBuilder.precomputedUpdateItemsByDiffingModels(
oldGroupModel: oldGroupModel.groupModel,
newGroupModel: newGroupModel.groupModel,
oldDisappearingMessageToken: oldGroupModel.dmToken,
newDisappearingMessageToken: newGroupModel.dmToken,
localIdentifiers: localIdentifiers,
groupUpdateSource: updateMetadata.source,
tx: tx
)
}
return transformer(
groupUpdateItemBuilder,
precomputedItems,
tx
)
}
/// We only stored this legacy data before we persisted the new ``TSInfoMessage.PersistableGroupUpdateItem``,
/// so it lives either alongside a model diff or alongside ``TSInfoMessage.LegacyPersistableGroupUpdateItem``.
private var persistedLegacyUpdateMetadata: GroupUpdateMetadata.UpdateMetadata {
let source = Self.legacyGroupUpdateSource(infoMessageUserInfoDict: infoMessageUserInfo)
// We grab this legacy value if we have it; its irrelevant for new persistable
// update items which know if they are from the local user or not.
let updaterWasLocalUser: Bool = infoMessageValue(forKey: .legacyUpdaterKnownToBeLocalUser) ?? false
return GroupUpdateMetadata.UpdateMetadata(
source: source,
updaterWasLocalUser: updaterWasLocalUser
)
}
}