//
//  SimpleStopWatch.swift
//  WorkoutsPlus
//
//  Created by Felix Förtsch on 12.09.24.
//
import SwiftUI

struct SimpleStopWatch: View {
		@State var startDate: Date
		@Binding var duration: TimeInterval
		
		@State private var isPaused = false
		@State private var timeString: String = "00:00:00"
		@State private var timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
		
		var body: some View {
				Text(timeString)
						.onReceive(timer) { _ in
								if !isPaused {
										duration += 1
										timeString = format(time: duration)
								}
						}
						.onTapGesture {
								isPaused.toggle()
						}
						.onAppear() {
								duration = Date().timeIntervalSince(startDate)
								timeString = format(time: duration)
								startTimer()
						}
						.onDisappear() {
								stopTimer()
						}
		}
		
		private func stopTimer() {
				timer.upstream.connect().cancel()
		}
		
		private func startTimer() {
				timer = Timer.publish(every: 1, on: .main, in: .common).autoconnect()
		}
		
		private func format(time: TimeInterval) -> String {
				let totalTimeInSeconds = Int(time)
				
				let hours = totalTimeInSeconds / 3600
				let minutes = (totalTimeInSeconds % 3600) / 60
				let seconds = totalTimeInSeconds % 60
				
				var formattedTime = ""
				if hours > 0 {
						formattedTime += String(format: "%d:", hours)
				}
				formattedTime += String(format: "%02d:%02d", minutes, seconds)
				
				return formattedTime
		}
}

#Preview {
		@Previewable @State var duration = 0.0
		SimpleStopWatch(startDate: Date.now, duration: $duration)
}