refactor: Adding structure

Huge refactor to add better structure to the project.
Separating features with their associated view and model structure.
This should be better organization and will allow us to improve the
overall architecture in the future.

I forsee many more improvements that can follow this change. e.g. MVVM Arch
As well as cleaning up duplicate, unused, functionality.
Many files have global functions that can also be moved or be renamed.

damus/
├── Features/
│   ├── <Feature>/
│   │   ├── Views/
│   │   └── Models/
├── Shared/
│   ├── Components/
│   ├── Media/
│   ├── Buttons/
│   ├── Extensions/
│   ├── Empty Views/
│   ├── ErrorHandling/
│   ├── Modifiers/
│   └── Utilities/
├── Core/
│   ├── Nostr/
│   ├── NIPs/
│   ├── DIPs/
│   ├── Types/
│   ├── Networking/
│   └── Storage/

Signed-off-by: ericholguin <ericholguin@apache.org>

damus/Features/Bookmarks/Models/BookmarksManager.swift

@@ -0,0 +1,70 @@
+//
+//  BookmarksManager.swift
+//  damus
+//
+//  Created by Joel Klabo on 2/18/23.
+//
+
+import Foundation
+
+fileprivate func get_bookmarks_key(pubkey: Pubkey) -> String {
+    pk_setting_key(pubkey, key: "bookmarks")
+}
+
+func load_bookmarks(pubkey: Pubkey) -> [NostrEvent] {
+    let key = get_bookmarks_key(pubkey: pubkey)
+    return (UserDefaults.standard.stringArray(forKey: key) ?? []).compactMap {
+        event_from_json(dat: $0)
+    }
+}
+
+func save_bookmarks(pubkey: Pubkey, current_value: [NostrEvent], value: [NostrEvent]) -> Bool {
+    let uniq_bookmarks = uniq(value)
+    
+    if uniq_bookmarks != current_value {
+        let encoded = uniq_bookmarks.map(event_to_json)
+        UserDefaults.standard.set(encoded, forKey: get_bookmarks_key(pubkey: pubkey))
+        return true
+    }
+    
+    return false
+}
+
+class BookmarksManager: ObservableObject {
+    
+    private let pubkey: Pubkey
+
+    private var _bookmarks: [NostrEvent]
+    var bookmarks: [NostrEvent] {
+        get {
+            return _bookmarks
+        }
+        set {
+            if save_bookmarks(pubkey: pubkey, current_value: _bookmarks, value: newValue) {
+                self._bookmarks = newValue
+                self.objectWillChange.send()
+            }
+        }
+    }
+    
+    init(pubkey: Pubkey) {
+        self._bookmarks = load_bookmarks(pubkey: pubkey)
+        self.pubkey = pubkey
+    }
+    
+    func isBookmarked(_ ev: NostrEvent) -> Bool {
+        return bookmarks.contains(ev)
+    }
+    
+    func updateBookmark(_ ev: NostrEvent) {
+        if isBookmarked(ev) {
+            bookmarks = bookmarks.filter { $0 != ev }
+        } else {
+            bookmarks.insert(ev, at: 0)
+        }
+    }
+    
+    func clearAll() {
+        bookmarks = []
+    }
+}

damus/Features/Bookmarks/Views/BookmarksView.swift

@@ -0,0 +1,73 @@
+//
+//  BookmarksView.swift
+//  damus
+//
+//  Created by Joel Klabo on 2/18/23.
+//
+
+import SwiftUI
+
+struct BookmarksView: View {
+    let state: DamusState
+    private let noneFilter: (NostrEvent) -> Bool = { _ in true }
+    private let bookmarksTitle = NSLocalizedString("Bookmarks", comment: "Title of bookmarks view")
+    @State private var clearAllAlert: Bool = false
+    
+    @Environment(\.dismiss) var dismiss
+    @ObservedObject var manager: BookmarksManager
+
+    init(state: DamusState) {
+        self.state = state
+        self._manager = ObservedObject(initialValue: state.bookmarks)
+    }
+    
+    var bookmarks: [NostrEvent] {
+        manager.bookmarks
+    }
+        
+    var body: some View {
+        Group {
+            if bookmarks.isEmpty {
+                VStack {
+                    Image("bookmark")
+                        .resizable()
+                        .scaledToFit()
+                        .frame(width: 32.0, height: 32.0)
+                    Text("You have no bookmarks yet, add them in the context menu", comment: "Text indicating that there are no bookmarks to be viewed")
+                }
+            } else {
+                ScrollView {
+                    InnerTimelineView(events: EventHolder(events: bookmarks, incoming: []), damus: state, filter: noneFilter)
+                }
+                .padding(.bottom, 10 + tabHeight + getSafeAreaBottom())
+            }
+        }
+        .onReceive(handle_notify(.switched_timeline)) { _ in
+            dismiss()
+        }
+        .navigationBarTitleDisplayMode(.inline)
+        .navigationTitle(bookmarksTitle)
+        .toolbar {
+            if !bookmarks.isEmpty {
+                Button(NSLocalizedString("Clear All", comment: "Button for clearing bookmarks data.")) {
+                    clearAllAlert = true
+                }
+            }
+        }
+        .alert(NSLocalizedString("Are you sure you want to delete all of your bookmarks?", comment: "Alert for deleting all of the bookmarks."), isPresented: $clearAllAlert) {
+            Button(NSLocalizedString("Cancel", comment: "Cancel deleting bookmarks."), role: .cancel) {
+            }
+            Button(NSLocalizedString("Continue", comment: "Continue with bookmarks.")) {
+                manager.clearAll()
+            }
+        }
+    }
+}
+
+/*
+struct BookmarksView_Previews: PreviewProvider {
+ static var previews: some View {
+    BookmarksView()
+ }
+}
+ */