m3_lightmeter/lib/screens/timer/screen_timer.dart

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:lightmeter/data/models/exposure_pair.dart';
import 'package:lightmeter/res/dimens.dart';
import 'package:lightmeter/screens/shared/animated_circular_button/widget_button_circular_animated.dart';
import 'package:lightmeter/screens/shared/bottom_controls_bar/widget_bottom_controls_bar.dart';
import 'package:lightmeter/screens/timer/bloc_timer.dart';
import 'package:lightmeter/screens/timer/components/metering_config/widget_metering_config_timer.dart';
import 'package:lightmeter/screens/timer/components/text/widget_text_timer.dart';
import 'package:lightmeter/screens/timer/components/timeline/widget_timeline_timer.dart';
import 'package:lightmeter/screens/timer/event_timer.dart';
import 'package:lightmeter/screens/timer/state_timer.dart';
import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';

class TimerScreen extends StatefulWidget {
  final ExposurePair exposurePair;
  final IsoValue isoValue;
  final NdValue ndValue;
  final Duration duration;

  const TimerScreen({
    required this.exposurePair,
    required this.isoValue,
    required this.ndValue,
    required this.duration,
    super.key,
  });

  @override
  State<TimerScreen> createState() => TimerScreenState();
}

@visibleForTesting
class TimerScreenState extends State<TimerScreen> with TickerProviderStateMixin {
  late AnimationController timelineController;
  late Animation<double> timelineAnimation;
  late AnimationController startStopIconController;
  late Animation<double> startStopIconAnimation;

  @override
  void initState() {
    super.initState();

    timelineController = AnimationController(vsync: this, duration: widget.duration);
    timelineAnimation = Tween<double>(begin: 1, end: 0).animate(timelineController);
    timelineController.addStatusListener((status) {
      if (timelineController.value == 1) {
        Navigator.of(context).pop();
      } else if (status == AnimationStatus.completed) {
        context.read<TimerBloc>().add(const TimerEndedEvent());
      }
    });

    startStopIconController = AnimationController(vsync: this, duration: Dimens.durationS);
    startStopIconAnimation = Tween<double>(begin: 0, end: 1).animate(startStopIconController);
  }

  @override
  void dispose() {
    timelineController.dispose();
    startStopIconController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return BlocListener<TimerBloc, TimerState>(
      listenWhen: (previous, current) => previous.runtimeType != current.runtimeType,
      listener: (context, state) => _updateAnimations(state),
      child: Scaffold(
        backgroundColor: Theme.of(context).colorScheme.background,
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              TimerMeteringConfig(
                exposurePair: widget.exposurePair,
                isoValue: widget.isoValue,
                ndValue: widget.ndValue,
              ),
              const Spacer(),
              Padding(
                padding: const EdgeInsets.all(Dimens.paddingL),
                child: SizedBox.fromSize(
                  size: Size.square(MediaQuery.sizeOf(context).width - Dimens.paddingL * 4),
                  child: ValueListenableBuilder(
                    valueListenable: timelineAnimation,
                    builder: (_, value, child) => TimerTimeline(
                      progress: value,
                      child: TimerText(
                        timeLeft: Duration(milliseconds: (widget.duration.inMilliseconds * value).toInt()),
                        duration: widget.duration,
                      ),
                    ),
                  ),
                ),
              ),
              const Spacer(),
              BottomControlsBar(
                left: IconButton(
                  onPressed: () {
                    context.read<TimerBloc>().add(const ResetTimerEvent());
                  },
                  icon: const Icon(Icons.restore),
                ),
                center: BlocBuilder<TimerBloc, TimerState>(
                  builder: (_, state) => AnimatedCircluarButton(
                    isPressed: state is TimerResumedState,
                    onPressed: () {
                      if (timelineAnimation.value == 0) {
                        return;
                      }
                      final event = state is TimerStoppedState ? const StartTimerEvent() : const StopTimerEvent();
                      context.read<TimerBloc>().add(event);
                    },
                    child: AnimatedIcon(
                      icon: AnimatedIcons.play_pause,
                      progress: startStopIconAnimation,
                      color: Theme.of(context).colorScheme.surface,
                    ),
                  ),
                ),
                right: const CloseButton(),
              ),
            ],
          ),
        ),
      ),
    );
  }

  void _updateAnimations(TimerState state) {
    switch (state) {
      case TimerResetState():
        startStopIconController.reverse();
        timelineController.stop();
        timelineController.animateTo(0, duration: Dimens.durationS);
      case TimerResumedState():
        startStopIconController.forward();
        timelineController.forward();
      case TimerStoppedState():
        startStopIconController.reverse();
        timelineController.stop();
    }
  }
}