/*
 * Copyright (c) 2010-2023 Belledonne Communications SARL.
 *
 * This file is part of linphone-iphone
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

import SwiftUI

struct ConversationFragment: View {
	
	@State private var orientation = UIDevice.current.orientation
	
	@ObservedObject var contactsManager = ContactsManager.shared
	
	@ObservedObject var conversationViewModel: ConversationViewModel
	@ObservedObject var conversationsListViewModel: ConversationsListViewModel
	
	@State var isMenuOpen = false
	
	@FocusState var isMessageTextFocused: Bool
	
	@State var offset: CGPoint = .zero
	
	private let ids: [String] = []
	
	@State private var isScrolledToBottom: Bool = true
	var showMessageMenuOnLongPress: Bool = true
	
	@StateObject private var viewModel = ChatViewModel()
	@StateObject private var paginationState = PaginationState()
	
	var body: some View {
		NavigationView {
			GeometryReader { geometry in
				VStack(spacing: 1) {
					if conversationViewModel.displayedConversation != nil {
						Rectangle()
							.foregroundColor(Color.orangeMain500)
							.edgesIgnoringSafeArea(.top)
							.frame(height: 0)
						
						HStack {
							if !(orientation == .landscapeLeft || orientation == .landscapeRight
								 || UIScreen.main.bounds.size.width > UIScreen.main.bounds.size.height) {
								Image("caret-left")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: 25, height: 25, alignment: .leading)
									.padding(.all, 10)
									.padding(.top, 4)
									.padding(.leading, -10)
									.onTapGesture {
										withAnimation {
											conversationViewModel.displayedConversation = nil
										}
									}
							}
							
							Avatar(contactAvatarModel: conversationViewModel.displayedConversation!.avatarModel, avatarSize: 50)
								.padding(.top, 4)
							
							Text(conversationViewModel.displayedConversation!.subject)
								.default_text_style(styleSize: 16)
								.frame(maxWidth: .infinity, alignment: .leading)
								.padding(.top, 4)
								.lineLimit(1)
							
							Spacer()
							
							Button {
							} label: {
								Image("phone")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: 25, height: 25, alignment: .leading)
									.padding(.all, 10)
									.padding(.top, 4)
							}
							
							Menu {
								Button {
									isMenuOpen = false
								} label: {
									HStack {
										Text("See contact")
										Spacer()
										Image("user-circle")
											.resizable()
											.frame(width: 25, height: 25, alignment: .leading)
											.padding(.all, 10)
									}
								}
								
								Button {
									isMenuOpen = false
								} label: {
									HStack {
										Text("Copy SIP address")
										Spacer()
										Image("copy")
											.resizable()
											.frame(width: 25, height: 25, alignment: .leading)
											.padding(.all, 10)
									}
								}
								
								Button(role: .destructive) {
									isMenuOpen = false
								} label: {
									HStack {
										Text("Delete history")
										Spacer()
										Image("trash-simple-red")
											.resizable()
											.frame(width: 25, height: 25, alignment: .leading)
											.padding(.all, 10)
									}
								}
							} label: {
								Image("dots-three-vertical")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: 25, height: 25, alignment: .leading)
									.padding(.all, 10)
									.padding(.top, 4)
							}
							.onTapGesture {
								isMenuOpen = true
							}
						}
						.frame(maxWidth: .infinity)
						.frame(height: 50)
						.padding(.horizontal)
						.padding(.bottom, 4)
						.background(.white)
						
						if #available(iOS 16.0, *) {
							ZStack(alignment: .bottomTrailing) {
								UIList(viewModel: viewModel,
									   paginationState: paginationState,
									   conversationViewModel: conversationViewModel,
									   isScrolledToBottom: $isScrolledToBottom,
									   showMessageMenuOnLongPress: showMessageMenuOnLongPress,
									   geometryProxy: geometry,
									   sections: conversationViewModel.conversationMessagesSection,
									   ids: conversationViewModel.conversationMessagesIds
								)
								
								if !isScrolledToBottom {
									Button {
										NotificationCenter.default.post(name: .onScrollToBottom, object: nil)
									} label: {
										ZStack {
											
											Image("caret-down")
												.renderingMode(.template)
												.foregroundStyle(.white)
												.padding()
												.background(Color.orangeMain500)
												.clipShape(Circle())
												.shadow(color: .black.opacity(0.2), radius: 4)
											
											if conversationViewModel.displayedConversationUnreadMessagesCount > 0 {
												VStack {
													HStack {
														Spacer()
														
														HStack {
															Text(
																conversationViewModel.displayedConversationUnreadMessagesCount < 99
																? String(conversationViewModel.displayedConversationUnreadMessagesCount)
																: "99+"
															)
															.foregroundStyle(.white)
															.default_text_style(styleSize: 10)
															.lineLimit(1)
															
														}
														.frame(width: 18, height: 18)
														.background(Color.redDanger500)
														.cornerRadius(50)
													}
													
													Spacer()
												}
											}
										}
										
									}
									.frame(width: 50, height: 50)
									.padding()
								}
							}
							.onTapGesture {
								UIApplication.shared.endEditing()
							}
							.onAppear {
								conversationViewModel.getMessages()
							}
							.onDisappear {
								conversationViewModel.resetMessage()
							}
						} else {
							ScrollViewReader { proxy in
								List {
									ForEach(0..<conversationViewModel.conversationMessagesList.count, id: \.self) { index in
										if index < conversationViewModel.conversationMessagesSection.first!.rows.count {
											ChatBubbleView(conversationViewModel: conversationViewModel, message: conversationViewModel.conversationMessagesSection.first!.rows[index], geometryProxy: geometry)
											 .id(conversationViewModel.conversationMessagesList[index])
											 .listRowInsets(EdgeInsets(top: 2, leading: 10, bottom: 2, trailing: 10))
											 .listRowSeparator(.hidden)
											 .scaleEffect(x: 1, y: -1, anchor: .center)
											 .onAppear {
												 if index == conversationViewModel.conversationMessagesList.count - 1 && conversationViewModel.displayedConversationHistorySize > conversationViewModel.conversationMessagesList.count {
													 DispatchQueue.main.asyncAfter(deadline: .now() + 0.2) {
														 conversationViewModel.getOldMessages()
													 }
												 }
											 }
										}
									}
								}
								.scaleEffect(x: 1, y: -1, anchor: .center)
								.listStyle(.plain)
								.onTapGesture {
									UIApplication.shared.endEditing()
								}
								.onAppear {
									conversationViewModel.getMessages()
								}
								.onChange(of: conversationViewModel.conversationMessagesList) { _ in
									/*
									DispatchQueue.main.asyncAfter(deadline: .now() + 0.2) {
										if conversationViewModel.conversationMessagesList.count <= 30 {
											proxy.scrollTo(
												conversationViewModel.conversationMessagesList.first, anchor: .top
											)
										} else if conversationViewModel.conversationMessagesList.count >= conversationViewModel.displayedConversationHistorySize {
											proxy.scrollTo(
												conversationViewModel.conversationMessagesList[conversationViewModel.displayedConversationHistorySize%30], anchor: .top
											)
										} else {
											proxy.scrollTo(30, anchor: .top)
										}
									}
									 */
								}
								.onDisappear {
									conversationViewModel.resetMessage()
								}
							}
						}
						
						HStack(spacing: 0) {
							Button {
							} label: {
								Image("smiley")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: 28, height: 28, alignment: .leading)
									.padding(.all, 6)
									.padding(.top, 4)
							}
							.padding(.horizontal, isMessageTextFocused ? 0 : 2)
							
							Button {
							} label: {
								Image("paperclip")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: isMessageTextFocused ? 0 : 28, height: isMessageTextFocused ? 0 : 28, alignment: .leading)
									.padding(.all, isMessageTextFocused ? 0 : 6)
									.padding(.top, 4)
							}
							.padding(.horizontal, isMessageTextFocused ? 0 : 2)
							
							Button {
							} label: {
								Image("camera")
									.renderingMode(.template)
									.resizable()
									.foregroundStyle(Color.grayMain2c500)
									.frame(width: isMessageTextFocused ? 0 : 28, height: isMessageTextFocused ? 0 : 28, alignment: .leading)
									.padding(.all, isMessageTextFocused ? 0 : 6)
									.padding(.top, 4)
							}
							.padding(.horizontal, isMessageTextFocused ? 0 : 2)
							
							HStack {
								if #available(iOS 16.0, *) {
									TextField("Say something...", text: $conversationViewModel.messageText, axis: .vertical)
										.default_text_style(styleSize: 15)
										.focused($isMessageTextFocused)
										.padding(.vertical, 5)
								} else {
									ZStack(alignment: .leading) {
										TextEditor(text: $conversationViewModel.messageText)
											.multilineTextAlignment(.leading)
											.frame(maxHeight: 160)
											.fixedSize(horizontal: false, vertical: true)
											.default_text_style(styleSize: 15)
											.focused($isMessageTextFocused)
										
										if conversationViewModel.messageText.isEmpty {
											Text("Say something...")
												.padding(.leading, 4)
												.opacity(conversationViewModel.messageText.isEmpty ? 1 : 0)
												.foregroundStyle(Color.gray300)
												.default_text_style(styleSize: 15)
										}
									}
									.onTapGesture {
										isMessageTextFocused = true
									}
								}
								
								if conversationViewModel.messageText.isEmpty {
									Button {
									} label: {
										Image("microphone")
											.renderingMode(.template)
											.resizable()
											.foregroundStyle(Color.grayMain2c500)
											.frame(width: 28, height: 28, alignment: .leading)
											.padding(.all, 6)
											.padding(.top, 4)
									}
								} else {
									Button {
										NotificationCenter.default.post(name: .onScrollToBottom, object: nil)
										conversationViewModel.sendMessage()
									} label: {
										Image("paper-plane-tilt")
											.renderingMode(.template)
											.resizable()
											.foregroundStyle(Color.orangeMain500)
											.frame(width: 28, height: 28, alignment: .leading)
											.padding(.all, 6)
											.padding(.top, 4)
											.rotationEffect(.degrees(45))
									}
									.padding(.trailing, 4)
								}
							}
							.padding(.leading, 15)
							.padding(.trailing, 5)
							.padding(.vertical, 6)
							.frame(maxWidth: .infinity, minHeight: 55)
							.background(.white)
							.cornerRadius(30)
							.overlay(
								RoundedRectangle(cornerRadius: 30)
									.inset(by: 0.5)
									.stroke(Color.gray200, lineWidth: 1.5)
							)
							.padding(.horizontal, 4)
						}
						.frame(maxWidth: .infinity, minHeight: 60)
						.padding(.top, 12)
						.padding(.bottom, geometry.safeAreaInsets.bottom > 0 ? (isMessageTextFocused ? 12 : 0) : 12)
						.padding(.horizontal, 10)
						.background(Color.gray100)
					}
				}
				.background(.white)
				.navigationBarHidden(true)
				.onRotate { newOrientation in
					orientation = newOrientation
				}
				.onAppear {
					conversationViewModel.addConversationDelegate()
				}
				.onDisappear {
					conversationViewModel.removeConversationDelegate()
				}
			}
		}
		.navigationViewStyle(.stack)
	}
}

extension UIApplication {
	func endEditing() {
		sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
	}
}

/*
#Preview {
	ConversationFragment(conversationViewModel: ConversationViewModel(), conversationsListViewModel: ConversationsListViewModel(), sections: [MessagesSection], ids: [""])
}
*/