//
//  NoteEditorScreen.swift
//  Peered
//
//  Created by Oskar Chybowski on 25/09/2025.
//

import MultipeerConnectivity
import SwiftUI

struct NoteEditorScreen: View {
  let note: Note
  @State private var noteAdvertiser: NoteEditingSessionServer
  @State private var noteContent: String = ""
  @State private var remoteNoteContent: String? = nil
  @State private var timer = Timer.publish(every: 5, on: .current, in: .common)
    .autoconnect()
  @State private var showManageMembers = false

  init(note: Note, peer: OwnPeer) {
    self.note = note
    self._noteAdvertiser = .init(initialValue: .init(peer: peer))
  }

  var body: some View {
    NoteTextEditor(text: $noteContent, remoteText: remoteNoteContent)
      .toolbar {
        ToolbarItem(placement: .primaryAction) {
          Button("Manage members") {
            showManageMembers = true
          }
        }
      }
      .sheet(isPresented: $showManageMembers) {
        NavigationStack {
          ManageMembersScreen(
            noteAdvertiser: noteAdvertiser,
            noteTitle: note.name,
            noteContent: $noteContent
          )
        }
      }
      .onReceive(noteAdvertiser.noteChangesEmitter) { message in
        guard message.senderID != noteAdvertiser.ownPeer.peer.displayName else { return }
        remoteNoteContent = message.content
      }
      .task(id: noteContent) {
        if noteContent == remoteNoteContent { return }
        let connectedPeers = noteAdvertiser.visiblePeers
          .filter { $0.state == .joined }
          .map(\.mcPeer)
        guard !connectedPeers.isEmpty else { return }
        try? await Task.sleep(nanoseconds: 500_000_000)
        guard !Task.isCancelled else { return }
        noteAdvertiser.send(note: noteContent, to: connectedPeers)
      }
      .onAppear {
        noteContent = (try? String(contentsOf: note.path, encoding: .utf8)) ?? ""
        noteAdvertiser.startServer()
      }
      .onDisappear {
        noteAdvertiser.stopServer()
        saveNote()
      }
      .onReceive(timer) { _ in
        saveNote()
      }
  }

  func saveNote() {
    try? noteContent.write(to: note.path, atomically: true, encoding: .utf8)
  }
}