another.im-ios/AnotherXMPP/modules/presence/PresenceModule.swift

import Foundation

// NSString* const kSubBoth = @"both";
// NSString* const kSubNone = @"none";
// NSString* const kSubTo = @"to";
// NSString* const kSubFrom = @"from";
// NSString* const kSubRemove = @"remove";
// NSString* const kAskSubscribe = @"subscribe";

// TODO: Cancel subscr. request when contact deleted from roster
// Update when server sends roster push also
final class PresenceModule: XmppModule {
    let id = "Presence module"

    func reduce(oldState: ClientState, with _: Event) -> ClientState {
        oldState
    }

    func process(state _: ClientState, with event: Event) async -> Event? {
        switch event {
        case .rosterRequestDone:
            guard let initial = Stanza.initialPresence() else { return nil }
            return .stanzaOutbound(initial)

        case .stanzaInbound(let stanza):
            return nil

        default:
            return nil
        }
    }
}