using System.Collections.ObjectModel;
using System.Windows;
using System.Windows.Controls;

namespace OmniScheduler;

public partial class TaskEditorWindow : Window
{
    private readonly ScheduledTask _task;
    private readonly AppSettings _settings;
    private readonly NotifyClient _client;
    private bool _loading;

    private TaskEditorWindow(Window owner, ScheduledTask task, AppSettings settings, NotifyClient client)
    {
        InitializeComponent();
        Owner = owner;
        _task = task;
        _settings = settings;
        _client = client;

        KindBox.ItemsSource = Enum.GetValues<TriggerKind>();
        IntervalUnitBox.ItemsSource = Enum.GetValues<IntervalUnit>();
        MisfireBox.ItemsSource = Enum.GetValues<MisfireStrategy>();
        ChannelBox.ItemsSource = owner is MainWindow main
            ? main.State.Tasks.Select(t => t.Channel).Where(c => !string.IsNullOrWhiteSpace(c)).Distinct().ToList()
            : null;

        LoadTask();
    }

    public static bool Edit(Window owner, ScheduledTask task, AppSettings settings, NotifyClient client)
    {
        var workingCopy = task.Clone();
        workingCopy.Id = task.Id;
        workingCopy.Name = task.Name;
        var dialog = new TaskEditorWindow(owner, workingCopy, settings, client);
        if (dialog.ShowDialog() == true)
        {
            task.CopyFrom(workingCopy);
            return true;
        }

        return false;
    }

    private void LoadTask()
    {
        NameBox.Text = _task.Name;
        DescriptionBox.Text = _task.Description;
        EnabledBox.IsChecked = _task.IsEnabled;
        TargetUrlBox.Text = _settings.OmniNotifyUrl;
        ChannelBox.Text = _task.Channel;
        TitleBox.Text = _task.Title;
        BodyBox.Text = _task.Body;
        MisfireBox.SelectedItem = _task.MisfireStrategy;
        TriggersList.ItemsSource = _task.Triggers;
        TriggersList.SelectedIndex = _task.Triggers.Count > 0 ? 0 : -1;
    }

    private void LoadTrigger(TaskTrigger? trigger)
    {
        _loading = true;
        try
        {
            if (trigger is null)
            {
                return;
            }

            KindBox.SelectedItem = trigger.Kind;
            OneTimeBox.Text = trigger.OneTimeAt.ToString("yyyy-MM-dd HH:mm:ss");
            IntervalValueBox.Text = trigger.IntervalValue.ToString();
            IntervalUnitBox.SelectedItem = trigger.IntervalUnit;
            StartsAtBox.Text = trigger.StartsAt?.ToString("yyyy-MM-dd HH:mm:ss") ?? "";
            EndsAtBox.Text = trigger.EndsAt?.ToString("yyyy-MM-dd HH:mm:ss") ?? "";
            TimeOfDayBox.Text = trigger.TimeOfDay.ToString(@"hh\:mm\:ss");
            MonthDayBox.Text = trigger.MonthDay.ToString();
            LastBusinessDayBox.IsChecked = trigger.LastBusinessDay;
            CronBox.Text = trigger.CronExpression;

            SunBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Sunday);
            MonBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Monday);
            TueBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Tuesday);
            WedBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Wednesday);
            ThuBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Thursday);
            FriBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Friday);
            SatBox.IsChecked = trigger.WeekDays.HasFlag(DayOfWeekFlags.Saturday);
        }
        finally
        {
            _loading = false;
            RefreshPreview();
        }
    }

    private bool SaveTriggerFields()
    {
        if (_loading || TriggersList.SelectedItem is not TaskTrigger trigger)
        {
            return true;
        }

        trigger.Kind = KindBox.SelectedItem is TriggerKind kind ? kind : TriggerKind.Interval;
        trigger.IntervalUnit = IntervalUnitBox.SelectedItem is IntervalUnit unit ? unit : IntervalUnit.Minutes;
        trigger.LastBusinessDay = LastBusinessDayBox.IsChecked == true;
        trigger.CronExpression = CronBox.Text.Trim();

        if (int.TryParse(IntervalValueBox.Text, out var interval))
        {
            trigger.IntervalValue = interval;
        }

        if (int.TryParse(MonthDayBox.Text, out var monthDay))
        {
            trigger.MonthDay = Math.Clamp(monthDay, 1, 31);
        }

        if (DateTime.TryParse(OneTimeBox.Text, out var oneTime))
        {
            trigger.OneTimeAt = oneTime;
        }

        trigger.StartsAt = DateTime.TryParse(StartsAtBox.Text, out var startsAt) ? startsAt : null;
        trigger.EndsAt = DateTime.TryParse(EndsAtBox.Text, out var endsAt) ? endsAt : null;

        if (TimeSpan.TryParse(TimeOfDayBox.Text, out var time))
        {
            trigger.TimeOfDay = time;
        }

        var days = DayOfWeekFlags.None;
        if (SunBox.IsChecked == true) days |= DayOfWeekFlags.Sunday;
        if (MonBox.IsChecked == true) days |= DayOfWeekFlags.Monday;
        if (TueBox.IsChecked == true) days |= DayOfWeekFlags.Tuesday;
        if (WedBox.IsChecked == true) days |= DayOfWeekFlags.Wednesday;
        if (ThuBox.IsChecked == true) days |= DayOfWeekFlags.Thursday;
        if (FriBox.IsChecked == true) days |= DayOfWeekFlags.Friday;
        if (SatBox.IsChecked == true) days |= DayOfWeekFlags.Saturday;
        trigger.WeekDays = days;
        trigger.Notify(nameof(TaskTrigger.Summary));
        TriggersList.Items.Refresh();
        RefreshPreview();
        return true;
    }

    private bool SaveTaskFields()
    {
        ValidationText.Text = "";
        SaveTriggerFields();

        if (string.IsNullOrWhiteSpace(NameBox.Text))
        {
            ValidationText.Text = "任务名称不能为空";
            return false;
        }

        foreach (var trigger in _task.Triggers)
        {
            if (trigger.Kind == TriggerKind.Interval && trigger.IntervalValue < 1)
            {
                ValidationText.Text = "固定间隔不能小于 1";
                return false;
            }
        }

        _task.Name = NameBox.Text.Trim();
        _task.Description = DescriptionBox.Text.Trim();
        _task.IsEnabled = EnabledBox.IsChecked == true;
        _task.Channel = ChannelBox.Text.Trim();
        _task.Title = TitleBox.Text.Trim();
        _task.Body = BodyBox.Text;
        _task.MisfireStrategy = MisfireBox.SelectedItem is MisfireStrategy strategy ? strategy : MisfireStrategy.DoNothing;
        return true;
    }

    private void TriggersList_SelectionChanged(object sender, SelectionChangedEventArgs e)
        => LoadTrigger(TriggersList.SelectedItem as TaskTrigger);

    private void AddTrigger_Click(object sender, RoutedEventArgs e)
    {
        var trigger = new TaskTrigger();
        _task.Triggers.Add(trigger);
        TriggersList.SelectedItem = trigger;
        TriggersList.Items.Refresh();
    }

    private void RemoveTrigger_Click(object sender, RoutedEventArgs e)
    {
        if (TriggersList.SelectedItem is TaskTrigger trigger)
        {
            _task.Triggers.Remove(trigger);
            TriggersList.Items.Refresh();
        }
    }

    private void Field_Changed(object sender, RoutedEventArgs e)
    {
        if (!_loading)
        {
            SaveTriggerFields();
        }
    }

    private async void TestSend_Click(object sender, RoutedEventArgs e)
    {
        if (!SaveTaskFields())
        {
            return;
        }

        TestResultText.Text = "发送中...";
        var log = await _client.SendAsync(_task, "Test", _settings.OmniNotifyUrl);
        TestResultText.Text = log.Level == "INFO" ? "测试发送成功" : log.Message;
        TestResultText.Foreground = log.Level == "INFO"
            ? System.Windows.Media.Brushes.ForestGreen
            : System.Windows.Media.Brushes.Firebrick;
    }

    private void Save_Click(object sender, RoutedEventArgs e)
    {
        if (!SaveTaskFields())
        {
            return;
        }

        DialogResult = true;
    }

    private void Cancel_Click(object sender, RoutedEventArgs e)
        => DialogResult = false;

    private void RefreshPreview()
    {
        if (TriggersList.SelectedItem is not TaskTrigger trigger)
        {
            PreviewBox.Text = "";
            return;
        }

        var preview = NextRunCalculator.Preview(trigger, DateTime.Now);
        PreviewBox.Text = preview.Count == 0
            ? "无法计算未来执行时间，请检查规则。"
            : string.Join(Environment.NewLine, preview.Select(d => d.ToString("yyyy-MM-dd HH:mm:ss")));
    }
}