//
//  Stopwatch.swift
//  MultiChrono
//
//  Created by Beatrice Dellacà on 26/01/26.
//

import Foundation
import Combine

class Stopwatch: ObservableObject, Identifiable {
    let id = UUID()
    @Published var name: String
    @Published var elapsedTime: TimeInterval = 0
    @Published var isRunning: Bool = false
    
    private var timer: AnyCancellable?
    private var startTime: Date?
    private var accumulatedTime: TimeInterval = 0
    
    init(name: String) {
        self.name = name
    }
    
    deinit {
        timer?.cancel()
    }
    
    func start() {
        guard !isRunning else { return }
        
        startTime = Date()
        isRunning = true
        
        timer = Timer.publish(every: 0.1, on: .main, in: .common)
            .autoconnect()
            .sink { [weak self] _ in
                self?.tick()
            }
    }
    
    func pause() {
        guard isRunning else { return }
        
        timer?.cancel()
        timer = nil
        
        if let startTime = startTime {
            accumulatedTime += Date().timeIntervalSince(startTime)
        }
        
        isRunning = false
        startTime = nil
        
        // Ensure UI shows accurate accumulated time
        elapsedTime = accumulatedTime
    }
    
    func reset() {
        pause()
        accumulatedTime = 0
        elapsedTime = 0
    }
    
    private func tick() {
        guard let startTime = startTime else { return }
        elapsedTime = accumulatedTime + Date().timeIntervalSince(startTime)
    }
    
    var formattedTime: String {
        let hours = Int(elapsedTime) / 3600
        let minutes = Int(elapsedTime) / 60 % 60
        let seconds = Int(elapsedTime) % 60
        let tenths = Int((elapsedTime.truncatingRemainder(dividingBy: 1)) * 10)
        
        if hours > 0 {
            return String(format: "%02i:%02i:%02i.%01i", hours, minutes, seconds, tenths)
        } else {
            return String(format: "%02i:%02i.%01i", minutes, seconds, tenths)
        }
    }
}