//
//  ThreadV2View.swift
//  damus
//
//  Created by Thomas Tastet on 25/12/2022.
//

import SwiftUI

struct ThreadView: View {
    let state: DamusState
    
    @StateObject var thread: ThreadModel
    @Environment(\.dismiss) var dismiss
    
    var parent_events: [NostrEvent] {
        state.events.parent_events(event: thread.event)
    }
    
    var child_events: [NostrEvent] {
        state.events.child_events(event: thread.event)
    }
    
    var body: some View {
        ScrollViewReader { reader in
            ScrollView {
                LazyVStack {
                    // MARK: - Parents events view
                    ForEach(parent_events, id: \.id) { parent_event in
                        MutedEventView(damus_state: state,
                                       event: parent_event,
                                       scroller: reader,
                                       selected: false
                        )
                        .onTapGesture {
                            thread.set_active_event(parent_event, privkey: state.keypair.privkey)
                            scroll_to_event(scroller: reader, id: parent_event.id, delay: 0.1, animate: false)
                        }
                        
                        Divider()
                            .padding(.top, 4)
                            .padding(.leading, 25 * 2)
                    }.background(GeometryReader { geometry in
                        // get the height and width of the EventView view
                        let eventHeight = geometry.frame(in: .global).height
                        //                    let eventWidth = geometry.frame(in: .global).width
                        
                        // vertical gray line in the background
                        Rectangle()
                            .fill(Color.gray.opacity(0.25))
                            .frame(width: 2, height: eventHeight)
                            .offset(x: 25, y: 40)
                    })
                    
                    // MARK: - Actual event view
                    MutedEventView(
                        damus_state: state,
                        event: self.thread.event,
                        scroller: reader,
                        selected: true
                    )
                    .id(self.thread.event.id)
                    
                    ForEach(child_events, id: \.id) { child_event in
                        MutedEventView(
                            damus_state: state,
                            event: child_event,
                            scroller: nil,
                            selected: false
                        )
                        .onTapGesture {
                            thread.set_active_event(child_event, privkey: state.keypair.privkey)
                            scroll_to_event(scroller: reader, id: child_event.id, delay: 0.1, animate: false)
                        }

                        Divider()
                            .padding([.top], 4)
                    }
                }.padding()
            }.navigationBarTitle(NSLocalizedString("Thread", comment: "Navigation bar title for note thread."))
            .onAppear {
                thread.subscribe()
                scroll_to_event(scroller: reader, id: self.thread.event.id, delay: 0.0, animate: false)
            }
            .onDisappear {
                thread.unsubscribe()
            }
            .onReceive(handle_notify(.switched_timeline)) { notif in
                dismiss()
            }
        }
    }
}

struct ThreadView_Previews: PreviewProvider {
    static var previews: some View {
        let state = test_damus_state()
        let thread = ThreadModel(event: test_event, damus_state: state)
        ThreadView(state: state, thread: thread)
    }
}