Notifications

Changelog-Added: Add new Notifications View

damus/Models/NotificationsModel.swift

@@ -0,0 +1,294 @@
+//
+//  NotificationsModel.swift
+//  damus
+//
+//  Created by William Casarin on 2023-02-21.
+//
+
+import Foundation
+
+enum NotificationItem {
+    case repost(String, EventGroup)
+    case reaction(String, EventGroup)
+    case profile_zap(ZapGroup)
+    case event_zap(String, ZapGroup)
+    case reply(NostrEvent)
+    
+    var id: String {
+        switch self {
+        case .repost(let evid, _):
+            return "repost_" + evid
+        case .reaction(let evid, _):
+            return "reaction_" + evid
+        case .profile_zap:
+            return "profile_zap"
+        case .event_zap(let evid, _):
+            return "event_zap_" + evid
+        case .reply(let ev):
+            return "reply_" + ev.id
+        }
+    }
+    
+    var last_event_at: Int64 {
+        switch self {
+        case .reaction(_, let evgrp):
+            return evgrp.last_event_at
+        case .repost(_, let evgrp):
+            return evgrp.last_event_at
+        case .profile_zap(let zapgrp):
+            return zapgrp.last_event_at
+        case .event_zap(_, let zapgrp):
+            return zapgrp.last_event_at
+        case .reply(let reply):
+            return reply.created_at
+        }
+    }
+}
+
+class NotificationsModel: ObservableObject {
+    var incoming_zaps: [Zap]
+    var incoming_events: [NostrEvent]
+    var should_queue: Bool
+    
+    // mappings from events to
+    var zaps: [String: ZapGroup]
+    var profile_zaps: ZapGroup
+    var reactions: [String: EventGroup]
+    var reposts: [String: EventGroup]
+    var replies: [NostrEvent]
+    var has_reply: Set<String>
+    
+    @Published var notifications: [NotificationItem]
+    
+    init() {
+        self.zaps = [:]
+        self.reactions = [:]
+        self.reposts = [:]
+        self.replies = []
+        self.has_reply = Set()
+        self.should_queue = true
+        self.incoming_zaps = []
+        self.incoming_events = []
+        self.profile_zaps = ZapGroup()
+        self.notifications = []
+    }
+    
+    func uniq_pubkeys() -> [String] {
+        var pks = Set<String>()
+        
+        for ev in incoming_events {
+            pks.insert(ev.pubkey)
+        }
+        
+        for grp in reposts {
+            for ev in grp.value.events {
+                pks.insert(ev.pubkey)
+            }
+        }
+        
+        for ev in replies {
+            pks.insert(ev.pubkey)
+        }
+        
+        for zap in incoming_zaps {
+            pks.insert(zap.request.ev.pubkey)
+        }
+        
+        return Array(pks)
+    }
+    
+    func build_notifications() -> [NotificationItem] {
+        var notifs: [NotificationItem] = []
+        
+        for el in zaps {
+            let evid = el.key
+            let zapgrp = el.value
+            
+            let notif: NotificationItem = .event_zap(evid, zapgrp)
+            notifs.append(notif)
+        }
+        
+        if !profile_zaps.zaps.isEmpty {
+            notifs.append(.profile_zap(profile_zaps))
+        }
+        
+        for el in reposts {
+            let evid = el.key
+            let evgrp = el.value
+            
+            notifs.append(.repost(evid, evgrp))
+        }
+        
+        for el in reactions {
+            let evid = el.key
+            let evgrp = el.value
+            
+            notifs.append(.reaction(evid, evgrp))
+        }
+        
+        for reply in replies {
+            notifs.append(.reply(reply))
+        }
+        
+        notifs.sort { $0.last_event_at > $1.last_event_at }
+        return notifs
+    }
+    
+    
+    private func insert_repost(_ ev: NostrEvent) -> Bool {
+        guard let reposted_ev = ev.inner_event else {
+            return false
+        }
+        
+        let id = reposted_ev.id
+        
+        if let evgrp = self.reposts[id] {
+            return evgrp.insert(ev)
+        } else {
+            let evgrp = EventGroup()
+            self.reposts[id] = evgrp
+            return evgrp.insert(ev)
+        }
+    }
+    
+    private func insert_text(_ ev: NostrEvent) -> Bool {
+        guard !has_reply.contains(ev.id) else {
+            return false
+        }
+        
+        has_reply.insert(ev.id)
+        replies.append(ev)
+        
+        return true
+    }
+    
+    private func insert_reaction(_ ev: NostrEvent) -> Bool {
+        guard let ref_id = ev.referenced_ids.last else {
+            return false
+        }
+        
+        let id = ref_id.id
+        
+        if let evgrp = self.reactions[id] {
+            return evgrp.insert(ev)
+        } else {
+            let evgrp = EventGroup()
+            self.reactions[id] = evgrp
+            return evgrp.insert(ev)
+        }
+    }
+    
+    private func insert_event_immediate(_ ev: NostrEvent) -> Bool {
+        if ev.known_kind == .boost {
+            return insert_repost(ev)
+        } else if ev.known_kind == .like {
+            return insert_reaction(ev)
+        } else if ev.known_kind == .text {
+            return insert_text(ev)
+        }
+        
+        return false
+    }
+    
+    private func insert_zap_immediate(_ zap: Zap) -> Bool {
+        switch zap.target {
+        case .note(let notezt):
+            let id = notezt.note_id
+            if let zapgrp = self.zaps[notezt.note_id] {
+                return zapgrp.insert(zap)
+            } else {
+                let zapgrp = ZapGroup()
+                self.zaps[id] = zapgrp
+                return zapgrp.insert(zap)
+            }
+            
+        case .profile:
+            return profile_zaps.insert(zap)
+        }
+    }
+    
+    func insert_event(_ ev: NostrEvent) -> Bool {
+        if should_queue {
+            return insert_uniq_sorted_event_created(events: &incoming_events, new_ev: ev)
+        }
+        
+        if insert_event_immediate(ev) {
+            self.notifications = build_notifications()
+            return true
+        }
+        
+        return false
+    }
+    
+    func insert_zap(_ zap: Zap) -> Bool {
+        if should_queue {
+            return insert_uniq_sorted_zap_by_created(zaps: &incoming_zaps, new_zap: zap)
+        }
+        
+        if insert_zap_immediate(zap) {
+            self.notifications = build_notifications()
+            return true
+        }
+        
+        return false
+    }
+    
+    func filter(_ isIncluded: (NostrEvent) -> Bool)  {
+        var changed = false
+        var count = 0
+        
+        count = incoming_events.count
+        incoming_events = incoming_events.filter(isIncluded)
+        changed = changed || incoming_events.count != count
+        
+        count = profile_zaps.zaps.count
+        profile_zaps.zaps = profile_zaps.zaps.filter { zap in isIncluded(zap.request.ev) }
+        changed = changed || profile_zaps.zaps.count != count
+        
+        for el in reactions {
+            count = el.value.events.count
+            el.value.events = el.value.events.filter(isIncluded)
+            changed = changed || el.value.events.count != count
+        }
+        
+        for el in reposts {
+            count = el.value.events.count
+            el.value.events = el.value.events.filter(isIncluded)
+            changed = changed || el.value.events.count != count
+        }
+        
+        for el in zaps {
+            count = el.value.zaps.count
+            el.value.zaps = el.value.zaps.filter {
+                isIncluded($0.request.ev)
+            }
+            changed = changed || el.value.zaps.count != count
+        }
+        
+        count = replies.count
+        replies = replies.filter(isIncluded)
+        changed = changed || replies.count != count
+        
+        if changed {
+            self.notifications = build_notifications()
+        }
+    }
+    
+    func flush() -> Bool {
+        var inserted = false
+        
+        for zap in incoming_zaps {
+            inserted = insert_zap_immediate(zap) || inserted
+        }
+        
+        for event in incoming_events {
+            inserted = insert_event_immediate(event) || inserted
+        }
+        
+        if inserted {
+            self.notifications = build_notifications()
+        }
+        
+        return inserted
+    }
+}