| 1 | import Foundation |
| 2 | |
| 3 | /// "<name> is connecting and can't hear you yet" (spec §15.24, 2026-10-01). |
| 4 | /// |
| 5 | /// Paul asked for Zoom's "… is connecting to audio and cannot hear you yet": |
| 6 | /// the gap after someone joins, before their side is receiving and playing |
| 7 | /// your audio, said rather than talked into. Their own report's `hearing` |
| 8 | /// is the authority; a client that does not send one is judged on what this |
| 9 | /// app can see of its own audio reaching them. |
| 10 | /// |
| 11 | /// For each person from the moment they appear in the roster (or appear |
| 12 | /// again, or are given a new connection): |
| 13 | /// |
| 14 | /// - the words are said only once `grace` (1 s) has passed without their |
| 15 | /// hearing you, so an ordinary join says nothing; |
| 16 | /// - they go the moment their report lists you in `hearing` — "Samuel can |
| 17 | /// hear you now"; |
| 18 | /// - for a client that does not say who it hears, once the connection is up |
| 19 | /// and either their receiver reports show your audio reaching them or |
| 20 | /// they have made a report without the list; |
| 21 | /// - and never past `cap` (20 s), after which §15.20's and §15.23's words |
| 22 | /// speak for any problem. |
| 23 | /// |
| 24 | /// Your own mute does not matter: it is about their hearing you when you |
| 25 | /// speak. Pure: fed the facts as they are, with the time. The browser's |
| 26 | /// `connectingStep` is its twin. |
| 27 | struct ConnectingWatch: Equatable { |
| 28 | static let grace = 1.0 |
| 29 | static let cap = 20.0 |
| 30 | |
| 31 | /// One person as they are now. |
| 32 | struct Peer: Equatable { |
| 33 | /// The pair generation: a new one is a new connection, and they cannot |
| 34 | /// hear you on it yet. |
| 35 | var epoch: Int64 = 0 |
| 36 | /// Their report on you (`HearingRule.hearsYou`): listed, not listed, |
| 37 | /// or nil for no list at all. |
| 38 | var hearsMe: Bool? |
| 39 | /// They have made a media report. |
| 40 | var reported = false |
| 41 | /// The connection to them is up. |
| 42 | var connected = false |
| 43 | /// Their receiver reports say your audio reaches them. |
| 44 | var acked = false |
| 45 | } |
| 46 | |
| 47 | private struct Record: Equatable { |
| 48 | var epoch: Int64 |
| 49 | var since: Double |
| 50 | var done = false |
| 51 | var shown = false |
| 52 | } |
| 53 | private var records: [String: Record] = [:] |
| 54 | |
| 55 | init() {} |
| 56 | |
| 57 | /// People still in their first moments, whether or not the words show yet. |
| 58 | var joining: Set<String> { Set(records.filter { !$0.value.done }.keys) } |
| 59 | /// People whose tiles say it. |
| 60 | var shown: Set<String> { Set(records.filter { $0.value.shown }.keys) } |
| 61 | |
| 62 | /// One look at everyone but you. Returns the people whose words have just |
| 63 | /// gone because they can hear you, for "… can hear you now". |
| 64 | @discardableResult |
| 65 | mutating func observe(at now: Double, people: [String: Peer]) -> [String] { |
| 66 | for id in Array(records.keys) where people[id] == nil { records.removeValue(forKey: id) } |
| 67 | var cleared: [String] = [] |
| 68 | for (id, p) in people { |
| 69 | var r = records[id] ?? Record(epoch: p.epoch, since: now) |
| 70 | if r.epoch != p.epoch { r = Record(epoch: p.epoch, since: now) } |
| 71 | if !r.done { |
| 72 | let fallback = p.hearsMe == nil && p.connected && (p.acked || p.reported) |
| 73 | if p.hearsMe == true || fallback { |
| 74 | if r.shown { cleared.append(id) } |
| 75 | r.done = true |
| 76 | r.shown = false |
| 77 | } else if now - r.since >= Self.cap { |
| 78 | r.done = true |
| 79 | r.shown = false |
| 80 | } else { |
| 81 | r.shown = now - r.since >= Self.grace |
| 82 | } |
| 83 | } |
| 84 | records[id] = r |
| 85 | } |
| 86 | return cleared.sorted() |
| 87 | } |
| 88 | |
| 89 | /// What a person's tile says about them and you, in order (the browser's |
| 90 | /// `peerNotice`): in their first moments, their own more specific report |
| 91 | /// (their browser blocking sound, or no sound from you) and otherwise the |
| 92 | /// connecting words once the grace has passed — "Reconnecting" would be |
| 93 | /// wrong of a connection that has never been up; after that, §15.23's |
| 94 | /// "Reconnecting to …" first and then their reports. `connecting` is the |
| 95 | /// line that carries the moving ellipsis, and is never set beside |
| 96 | /// `notices`. |
| 97 | static func tile( |
| 98 | name: String, media: PeerMedia?, me: String, muted: Bool, joining: Bool, shown: Bool, |
| 99 | reconnecting: Bool |
| 100 | ) -> (notices: [String], connecting: String?) { |
| 101 | let reports = AudioWords.notices(name: name, media: media, me: me, muted: muted) |
| 102 | if joining { |
| 103 | if !reports.isEmpty { return (reports, nil) } |
| 104 | return ([], shown ? ConnectingWords.connecting(name) : nil) |
| 105 | } |
| 106 | return ((reconnecting ? [ReconnectWords.peer(name)] : []) + reports, nil) |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | /// This app's half of §15.24: whose audio it can say it hears. |
| 111 | enum HearingRule { |
| 112 | /// One connection's audio as it is now. |
| 113 | struct Facts: Equatable { |
| 114 | /// ICE connected or completed. |
| 115 | var connected = false |
| 116 | /// ICE failed or closed: the path is gone. |
| 117 | var bad = false |
| 118 | var hasReceiver = false |
| 119 | /// The audio receiver's track is live. |
| 120 | var receiverLive = false |
| 121 | /// Audio packets received on it so far. |
| 122 | var packets: UInt64 = 0 |
| 123 | /// Decoded audio frames that reached the receive tap since the last look. |
| 124 | var decoded = 0 |
| 125 | /// They say they are muted (or have no microphone). |
| 126 | var senderMuted = false |
| 127 | } |
| 128 | |
| 129 | /// Whether the audio path from someone is established. Once it is, it |
| 130 | /// stays so until the connection fails or closes. Established is: the |
| 131 | /// connection up, and either their audio arriving — packets received and |
| 132 | /// decoded frames coming out — on a live receiver, or, for someone who |
| 133 | /// says they are muted, nothing more than that: a muted sender may send |
| 134 | /// only silence, or no audio at all, and must not look unheard, because |
| 135 | /// the moment they unmute, it plays. The browser's `judgeHeard` is its |
| 136 | /// twin. A native app plays whatever it decodes: there is no autoplay |
| 137 | /// policy to refuse it. |
| 138 | static func heard(was: Bool, _ f: Facts) -> Bool { |
| 139 | if f.bad { return false } |
| 140 | if was { return true } |
| 141 | if !f.connected { return false } |
| 142 | if f.senderMuted, !f.hasReceiver || f.receiverLive { return true } |
| 143 | return f.receiverLive && f.packets > 0 && f.decoded > 0 |
| 144 | } |
| 145 | |
| 146 | /// Whether `hearing` has changed in a way worth a report: someone heard |
| 147 | /// who was not, or someone still here no longer heard. Someone who has |
| 148 | /// left is not news — every departure would otherwise cost a report from |
| 149 | /// everyone left — and the core carries their id, ignored, until the next |
| 150 | /// report for another reason. The browser's `hearingMoved` is its twin. |
| 151 | static func moved(from before: [String], to now: [String], present: Set<String>) -> Bool { |
| 152 | let was = Set(before) |
| 153 | let is_ = Set(now) |
| 154 | if !is_.subtracting(was).isEmpty { return true } |
| 155 | return !was.subtracting(is_).intersection(present).isEmpty |
| 156 | } |
| 157 | |
| 158 | /// A person's report on you: true when their `hearing` lists you, false |
| 159 | /// when it has a list and you are not on it, nil when it has no list — no |
| 160 | /// report yet, or a client from before §15.24. |
| 161 | static func hearsYou(_ media: PeerMedia?, me: String) -> Bool? { |
| 162 | guard let list = media?.hearing else { return nil } |
| 163 | return !me.isEmpty && list.contains(me) |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | /// The words (spec §15.24). The ellipsis is drawn apart from them |
| 168 | /// (`ConnectingText`), so VoiceOver hears the sentence and not the dots. |
| 169 | public enum ConnectingWords { |
| 170 | public static func connecting(_ name: String) -> String { "\(name) is connecting and can’t hear you yet" } |
| 171 | public static func canHear(_ name: String) -> String { "\(name) can hear you now" } |
| 172 | } |
| 173 | |
amadan