Thread Caching

Changelog-Added: Threads now load instantly and are cached

damus/ContentView.swift

@@ -81,7 +81,7 @@ struct ContentView: View {
     @State var event: NostrEvent? = nil
     @State var active_profile: String? = nil
     @State var active_search: NostrFilter? = nil
-    @State var active_event_id: String? = nil
+    @State var active_event: NostrEvent = test_event
     @State var profile_open: Bool = false
     @State var thread_open: Bool = false
     @State var search_open: Bool = false
@@ -176,7 +176,8 @@ struct ContentView: View {
             NavigationLink(destination: MaybeProfileView, isActive: $profile_open) {
                 EmptyView()
             }
-            NavigationLink(destination: MaybeThreadView, isActive: $thread_open) {
+            let thread = ThreadModel(event: active_event, damus_state: damus_state!)
+            NavigationLink(destination: ThreadView(state: damus_state!, thread: thread), isActive: $thread_open) {
                 EmptyView()
             }
             NavigationLink(destination: MaybeSearchView, isActive: $search_open) {
@@ -223,16 +224,6 @@ struct ContentView: View {
         }
     }
     
-    var MaybeThreadView: some View {
-        Group {
-            if let evid = self.active_event_id {
-                BuildThreadV2View(damus: damus_state!, event_id: evid)
-            } else {
-                EmptyView()
-            }
-        }
-    }
-    
     var MaybeProfileView: some View {
         Group {
             if let pk = self.active_profile {
@@ -352,7 +343,11 @@ struct ContentView: View {
                     active_profile = ref.ref_id
                     profile_open = true
                 } else if ref.key == "e" {
-                    active_event_id = ref.ref_id
+                    find_event(state: damus_state!, evid: ref.ref_id, find_from: nil) { ev in
+                        if let ev {
+                            active_event = ev
+                        }
+                    }
                     thread_open = true
                 }
             case .filter(let filt):
@@ -766,3 +761,45 @@ func setup_notifications() {
     }
 }
 
+
+func find_event(state: DamusState, evid: String, find_from: [String]?, callback: @escaping (NostrEvent?) -> ()) {
+    if let ev = state.events.lookup(evid) {
+        callback(ev)
+        return
+    }
+    
+    let subid = UUID().description
+    
+    var has_event = false
+    var filter = NostrFilter.filter_ids([ evid ])
+    filter.limit = 1
+    var attempts = 0
+    
+    state.pool.subscribe_to(sub_id: subid, filters: [filter], to: find_from) { relay_id, res  in
+        guard case .nostr_event(let ev) = res else {
+            return
+        }
+        
+        guard ev.subid == subid else {
+            return
+        }
+        
+        switch ev {
+        case .event(_, let ev):
+            has_event = true
+            callback(ev)
+            state.pool.unsubscribe(sub_id: subid)
+        case .eose:
+            if !has_event {
+                attempts += 1
+                if attempts == state.pool.descriptors.count / 2 {
+                    callback(nil)
+                }
+                state.pool.unsubscribe(sub_id: subid, to: [relay_id])
+            }
+        case .notice(_):
+            break
+        }
+
+    }
+}