RecordingTimer.swift

import Foundation

/// Dedicated timer for recording duration that doesn't trigger global AppState re-renders.
/// Only views that explicitly observe this class will update when duration changes.
@MainActor
class RecordingTimer: ObservableObject {
  static let shared = RecordingTimer()

  /// Current recording duration in seconds
  @Published private(set) var duration: TimeInterval = 0

  private var timer: Timer?
  private var startTime: Date?

  private init() {}

  /// Start the recording timer
  func start() {
    startTime = Date()
    duration = 0

    // Update every second
    timer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { [weak self] _ in
      Task { @MainActor in
        guard let self = self, let start = self.startTime else { return }
        self.duration = Date().timeIntervalSince(start)
      }
    }
  }

  /// Stop the recording timer
  func stop() {
    timer?.invalidate()
    timer = nil
    startTime = nil
  }

  /// Reset the timer to zero
  func reset() {
    stop()
    duration = 0
  }

  /// Restart the timer from zero (keeps running)
  func restart() {
    stop()
    start()
  }

  /// Formatted duration string (HH:MM:SS)
  var formattedDuration: String {
    let total = Int(duration)
    let hours = total / 3600
    let minutes = (total % 3600) / 60
    let seconds = total % 60
    return String(format: "%02d:%02d:%02d", hours, minutes, seconds)
  }
}