//
//  ChannelMessageList.swift
//  Meshtastic
//
//  Created by Garth Vander Houwen on 12/24/21.
//

import CoreData
import MeshtasticProtobufs
import OSLog
import SwiftUI

struct ChannelMessageList: View {
	@EnvironmentObject var appState: AppState
	@Environment(\.managedObjectContext) var context
	@EnvironmentObject var accessoryManager: AccessoryManager
	@FocusState var messageFieldFocused: Bool
	@ObservedObject var myInfo: MyInfoEntity
	@ObservedObject var channel: ChannelEntity
	@State private var replyMessageId: Int64 = 0
	@AppStorage("preferredPeripheralNum") private var preferredPeripheralNum = -1
	@State private var messageToHighlight: Int64 = 0
	@FetchRequest private var allPrivateMessages: FetchedResults<MessageEntity>
	
	init(myInfo: MyInfoEntity, channel: ChannelEntity) {
		self.myInfo = myInfo
		self.channel = channel
		
		// Configure fetch request here
		let request: NSFetchRequest<MessageEntity> = MessageEntity.fetchRequest()
		request.sortDescriptors = [
			NSSortDescriptor(keyPath: \MessageEntity.messageTimestamp, ascending: true)
		]
		request.predicate = NSPredicate(
			format: "channel == %ld AND toUser == nil AND isEmoji == false",
			channel.index
		)
		_allPrivateMessages = FetchRequest(fetchRequest: request)
	}
	
	func markMessagesAsRead() {
		do {
			for unreadMessage in allPrivateMessages.filter({ !$0.read }) {
				unreadMessage.read = true
			}
			try context.save()
			Logger.data.info("📖 [App] All unread messages marked as read.")
			appState.unreadChannelMessages = myInfo.unreadMessages
			context.refresh(myInfo, mergeChanges: true)
		} catch {
			Logger.data.error("Failed to read messages: \(error.localizedDescription, privacy: .public)")
		}
	}
	
	var body: some View {
		ScrollViewReader { scrollView in
			ScrollView {
				LazyVStack {
					ForEach(allPrivateMessages) { message in
						let thisMessageIndex = allPrivateMessages.firstIndex(of: message) ?? 0
						let previousMessage =  thisMessageIndex > 0 ? allPrivateMessages[thisMessageIndex - 1] : nil
						let currentUser: Bool = (Int64(preferredPeripheralNum) == message.fromUser?.num ? true : false)
						if message.displayTimestamp(aboveMessage: previousMessage) {
							Text(message.timestamp.formatted(date: .abbreviated, time: .shortened))
								.font(.caption)
								.foregroundColor(.gray)
						}
						if message.replyID > 0 {
							let messageReply = allPrivateMessages.first(where: { $0.messageId == message.replyID })
							HStack {
								Button {
									if let messageNum = messageReply?.messageId {
										withAnimation(.easeInOut(duration: 0.5)) {
											messageToHighlight = messageNum
										}
										scrollView.scrollTo(messageNum, anchor: .center)
										Task {
											try? await Task.sleep(nanoseconds: 1_000_000_000)
											withAnimation(.easeInOut(duration: 0.5)) {
												messageToHighlight = -1
											}
										}
									}
								} label: {
									Text(messageReply?.messagePayload ?? "EMPTY MESSAGE").foregroundColor(.accentColor).font(.caption2)
										.padding(10)
										.overlay(
											RoundedRectangle(cornerRadius: 18)
												.stroke(Color.blue, lineWidth: 0.5)
										)
									Image(systemName: "arrowshape.turn.up.left.fill")
										.symbolRenderingMode(.hierarchical)
										.imageScale(.large).foregroundColor(.accentColor)
										.padding(.trailing)
								}
							}
						}
						HStack(alignment: .bottom) {
							if currentUser { Spacer(minLength: 50) }
							if !currentUser {
								CircleText(text: message.fromUser?.shortName ?? "?", color: Color(UIColor(hex: UInt32(message.fromUser?.num ?? 0))), circleSize: 44)
									.padding(.all, 5)
									.offset(y: -7)
							}
							
							VStack(alignment: currentUser ? .trailing : .leading) {
								let isDetectionSensorMessage = message.portNum == Int32(PortNum.detectionSensorApp.rawValue)
								
								if !currentUser && message.fromUser != nil {
									Text("\(message.fromUser?.longName ?? "Unknown".localized ) (\(message.fromUser?.userId ?? "?"))")
										.font(.caption)
										.foregroundColor(.gray)
										.offset(y: 8)
								}
								
								HStack {
									MessageText(
										message: message,
										tapBackDestination: .channel(channel),
										isCurrentUser: currentUser
									) {
										self.replyMessageId = message.messageId
										self.messageFieldFocused = true
									}
									
									if currentUser && message.canRetry {
										RetryButton(message: message, destination: .channel(channel))
									}
								}
								
								TapbackResponses(message: message) {
									appState.unreadChannelMessages = myInfo.unreadMessages
								}
								
								HStack {
									let ackErrorVal = RoutingError(rawValue: Int(message.ackError))
									if currentUser && message.receivedACK {
										Text("\(ackErrorVal?.display ?? "Empty Ack Error")").fixedSize(horizontal: false, vertical: true)
											.foregroundStyle(ackErrorVal?.color ?? Color.red)
											.font(.caption2)
									} else if currentUser && message.ackError == 0 {
										Text("Waiting to be acknowledged. . .").font(.caption2).foregroundColor(.orange)
									} else if currentUser && !isDetectionSensorMessage {
										Text("\(ackErrorVal?.display ?? "Empty Ack Error")").fixedSize(horizontal: false, vertical: true)
											.foregroundStyle(ackErrorVal?.color ?? Color.red)
											.font(.caption2)
									}
								}
							}
							.padding(.bottom)
							.id(allPrivateMessages.firstIndex(of: message))
							
							if !currentUser {
								Spacer(minLength: 50)
							}
						}
						.padding([.leading, .trailing])
						.frame(maxWidth: .infinity)
						.id(message.messageId)
						.onAppear {
							if !message.read {
								markMessagesAsRead()
							}
						}
					}
					Color.clear
						.frame(height: 1)
						.id("bottomAnchor")
				}
			}
			.defaultScrollAnchor(.bottom)
			.defaultScrollAnchorTopAlignment()
			.defaultScrollAnchorBottomSizeChanges()
			.scrollDismissesKeyboard(.immediately)
			.onChange(of: messageFieldFocused) {
				if messageFieldFocused {
					DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
						scrollView.scrollTo("bottomAnchor", anchor: .bottom)
					}
				}
			}
			TextMessageField(
				destination: .channel(channel),
				replyMessageId: $replyMessageId,
				isFocused: $messageFieldFocused
			)
		}
		.navigationBarTitleDisplayMode(.inline)
		.toolbar {
			ToolbarItem(placement: .principal) {
				HStack {
					CircleText(text: String(channel.index), color: .accentColor, circleSize: 44).fixedSize()
					Text(String(channel.name ?? "Unknown").camelCaseToWords()).font(.headline)
				}
			}
			ToolbarItem(placement: .navigationBarTrailing) {
				ZStack {
					ConnectedDevice(
						deviceConnected: accessoryManager.isConnected,
						name: accessoryManager.activeConnection?.device.shortName ?? "?",
						mqttProxyConnected: accessoryManager.mqttProxyConnected && (channel.uplinkEnabled || channel.downlinkEnabled),
						mqttUplinkEnabled: channel.uplinkEnabled,
						mqttDownlinkEnabled: channel.downlinkEnabled,
						mqttTopic: accessoryManager.mqttManager.topic
					)
				}
			}
		}
	}
}