using System.Diagnostics.CodeAnalysis;
using System.IO;
using System.Linq;
using Content.Client.Audio.Midi;
using Robust.Client.AutoGenerated;
using Robust.Client.UserInterface;
using Robust.Client.UserInterface.Controls;
using Robust.Client.UserInterface.CustomControls;
using Robust.Client.UserInterface.XAML;
using Robust.Shared.Input;
using Robust.Shared.Random;
using Robust.Shared.Timing;
using Robust.Shared.Utility;
using static Robust.Client.UserInterface.Controls.BaseButton;
using Range = Robust.Client.UserInterface.Controls.Range;

namespace Content.Client.Instruments.UI;

[GenerateTypedNameReferences]
public sealed partial class FileMidiSource : InstrumentMidiSourceBase
{
    private const double RecoveryGracePeriod = 2.0;

    [Dependency] private IRobustRandom _random = default!;
    [Dependency] private MidiFileCollectionManager _midiCollection = default!;
    [Dependency] private IFileDialogManager _dialogs = default!;
    [Dependency] private IUserInterfaceManager _userInterfaceManager = default!;

    /// <summary>
    /// Raised when MIDI data should be played.
    /// </summary>
    public event Action<byte[]>? StartPlayingRequest;

    /// <summary>
    /// Raised when any currently playing MIDI track should be stopped.
    /// </summary>
    public event Action? StopPlayingRequest;

    /// <summary>
    /// Raised when the track position on the currently playing MIDI track should change.
    /// </summary>
    public event Action<int>? TrackPositionChangeRequest;

    /// <summary>
    /// Raised when looping MIDI tracks is toggled.
    /// </summary>
    public event Action<bool>? LoopingToggled;

    private readonly List<ResPath> _loadedTracks = [];
    private bool _isMidiFileDialogueWindowOpen;
    private bool _selectedInternally;
    private float _timeSinceLastRecoverAttempt;

    /// <summary>
    /// The Instrument playing the tracks. This is needed for the UI to read out current track time.
    /// on <see cref="FrameUpdate" />.
    /// </summary>
    public Entity<InstrumentComponent> Instrument;

    private bool IsShuffle => ShuffleButton.Pressed;
    private string CurrentFilter => FilterBar.Text;

    /// <inheritdoc />
    public override string ButtonName => Loc.GetString("instruments-component-menu-file-midi-source-button");

    /// <summary>
    /// Controls if MIDI should currently be played. This is connected to the play button.
    /// </summary>
    public bool IsPlaying
    {
        get => PlayButton.Pressed;
        set => PlayButton.Pressed = value;
    }

    public FileMidiSource()
    {
        RobustXamlLoader.Load(this);
        IoCManager.InjectDependencies(this);

        CurrentTrackLabel.Text = string.Empty;

        _midiCollection.MidiFileAdded += AddTrack;
        _midiCollection.MidiFileRemoved += RemoveTrack;
        _midiCollection.MidiFilesReset += ReloadTrackList;

        FilterBar.OnTextChanged += OnFilterBarTextChanged;
        TrackList.OnItemSelected += OnTrackListItemSelected;
        TrackList.OnItemDeselected += OnTrackListItemDeselected;
        AddButton.OnPressed += OnAddButtonPressed;
        RemoveButton.OnPressed += OnRemoveButtonPressed;
        PlayButton.OnToggled += OnPlayButtonToggled;
        LoopButton.OnToggled += OnLoopButtonToggled;
        ShuffleButton.OnPressed += OnShuffleButtonPressed;
        PlaybackSlider.OnValueChanged += OnPlaybackSliderValueChanged;
        PlaybackSlider.OnKeyBindUp += OnPlaybackSliderKeyBindUp;

        RemoveButton.TooltipSupplier = SupplyFileManagementTooltip;
        ReloadTrackList();
    }

    protected override void FrameUpdate(FrameEventArgs args)
    {
        base.FrameUpdate(args);

        if (PlaybackSlider.Grabbed)
            return;

        // Disable the playback button when nothing is selected and playing.
        PlayButton.Disabled = !TrackList.GetSelected().Any() && !Instrument.Comp.IsRendererAlive;

        if (!Instrument.Comp.IsMidiOpen)
        {
            ResetTrackIndicators();
            PlaybackSlider.Disabled = true;

            // My patience with the InstrumentSystem ran out, the system will be asked to play tracks until it behaves.
            if (!IsPlaying)
                return;

            _timeSinceLastRecoverAttempt += args.DeltaSeconds;
            if (!(_timeSinceLastRecoverAttempt > RecoveryGracePeriod))
                return;

            _timeSinceLastRecoverAttempt = 0;
            ReplayCurrentTrack();
        }
        else if (Instrument.Comp.IsRendererAlive)
        {
            PlaybackSlider.Disabled = false;
            PlaybackSlider.MaxValue = Instrument.Comp.PlayerTotalTick;
            PlaybackSlider.SetValueWithoutEvent(Instrument.Comp.PlayerTick);
            // TODO: SequencerTimeScale does not return the actual ticks/seconds, find solution.
            var totalTime =
                TimeSpan.FromSeconds(Math.Ceiling(Instrument.Comp.PlayerTotalTick /
                                                  Instrument.Comp.Renderer!.SequencerTimeScale));
            var currentTime =
                TimeSpan.FromSeconds(Math.Ceiling(Instrument.Comp.PlayerTick /
                                                  Instrument.Comp.Renderer!.SequencerTimeScale));
            TimeLabel.Text = totalTime.Hours < 1
                ? Loc.GetString(
                    "instruments-component-menu-files-track-playtime-seconds-minutes",
                    ("currentMinutes", currentTime.ToString("mm")),
                    ("currentSeconds", currentTime.ToString("ss")),
                    ("totalMinutes", totalTime.ToString("mm")),
                    ("totalSeconds", totalTime.ToString("ss")))
                : Loc.GetString(
                    "instruments-component-menu-files-track-playtime-seconds-minutes-hours",
                    ("currentHours", currentTime.ToString("hh")),
                    ("currentMinutes", currentTime.ToString("mm")),
                    ("currentSeconds", currentTime.ToString("ss")),
                    ("totalHours", totalTime.ToString("hh")),
                    ("totalMinutes", totalTime.ToString("mm")),
                    ("totalSeconds", totalTime.ToString("ss")));
        }
    }

    public override void Disable()
    {
        base.Disable();
        TrackList.ClearSelected();
        IsPlaying = false;
        StopPlayingRequest?.Invoke();
        CurrentTrackLabel.Text = string.Empty;
    }

    private void OnFilterBarTextChanged(LineEdit.LineEditEventArgs obj)
    {
        FilterTrackList();
    }

    private void OnTrackListItemSelected(ItemList.ItemListSelectedEventArgs obj)
    {
        UpdateFileRemoveButton();
        if (!_selectedInternally)
        {
            IsPlaying = false;
            StopPlaying();
        }
        else
        {
            PlayTrackListItem(obj.ItemIndex);
        }
    }

    private void OnTrackListItemDeselected(ItemList.ItemListDeselectedEventArgs obj)
    {
        RemoveButton.Disabled = true;
    }

    private async void OnAddButtonPressed(ButtonEventArgs obj)
    {
        try
        {
            if (_isMidiFileDialogueWindowOpen)
                return;

            var filters = new FileDialogFilters(new FileDialogFilters.Group("mid", "midi"));

            // TODO: Once the file dialogue manager can handle focusing or closing windows, improve this logic to close
            //  or focus the previously-opened window.
            _isMidiFileDialogueWindowOpen = true;
            var (stream, name) = await _dialogs.GetFileAndName(filters, FileAccess.Read);
            await using (stream)
            {
                // did the instrument menu get closed while waiting for the user to select a file?
                if (Disposed)
                    return;

                if (stream == null)
                    return;

                if (name != null)
                    await _midiCollection.AddMidiFile(new ResPath(name), stream);
            }
        }
        catch
        {
            _userInterfaceManager.Popup(Loc.GetString("instruments-component-menu-files-error"));
        }
        finally
        {
            _isMidiFileDialogueWindowOpen = false;
        }
    }

    private void OnRemoveButtonPressed(ButtonEventArgs obj)
    {
        if (TryGetSelectedTrackPath(out var trackPath) && trackPath is { } resPath)
            _midiCollection.RemoveMidiFile(resPath);
        UpdateFileRemoveButton();
    }

    private void OnPlayButtonToggled(ButtonToggledEventArgs obj)
    {
        UpdateFileRemoveButton();
        if (PlayButton.Pressed)
        {
            if (!TryGetSelectedTrack(out var track))
                return;

            StartPlaying(track);
        }
        else
        {
            StopPlaying();
        }
    }

    private void OnLoopButtonToggled(ButtonToggledEventArgs obj)
    {
        if (LoopButton.Pressed && ShuffleButton.Pressed)
            ShuffleButton.Pressed = false;

        LoopingToggled?.Invoke(LoopButton.Pressed);
    }

    private void OnShuffleButtonPressed(ButtonEventArgs obj)
    {
        if (ShuffleButton.Pressed && LoopButton.Pressed)
        {
            LoopingToggled?.Invoke(false);
            LoopButton.Pressed = false;
        }

        if (obj.Button.Pressed && !TrackList.GetSelected().Any())
            TrackList[_random.Next(0, TrackList.Count)].Selected = true;
    }

    private void OnPlaybackSliderValueChanged(Range _)
    {
        // Do not seek while still grabbing.
        if (PlaybackSlider.Grabbed)
            return;

        TrackPositionChangeRequest?.Invoke((int)Math.Ceiling(PlaybackSlider.Value));
    }

    private void OnPlaybackSliderKeyBindUp(GUIBoundKeyEventArgs obj)
    {
        if (obj.Function != EngineKeyFunctions.UIClick)
            return;

        TrackPositionChangeRequest?.Invoke((int)Math.Ceiling(PlaybackSlider.Value));
    }

    private Tooltip? SupplyFileManagementTooltip(Control? sender)
    {
        if (sender is not Button { Disabled: true })
            return null;

        var tooltipText = Loc.GetString("instruments-component-menu-files-file-remove-disabled-info");
        var tooltip = new Tooltip();
        tooltip.SetMessage(FormattedMessage.FromUnformatted(tooltipText));
        return tooltip;
    }

    private void UpdateFileRemoveButton()
    {
        RemoveButton.Disabled = !TrackList.GetSelected().Any() || IsPlaying;
    }

    private void ResetTrackIndicators()
    {
        PlaybackSlider.MaxValue = 1;
        PlaybackSlider.SetValueWithoutEvent(0);
        CurrentTrackLabel.Text = string.Empty;
        TimeLabel.Text = "--.--/--.--";
    }

    private void PlayTrackListItem(int index)
    {
        if (index >= TrackList.Count || index < 0)
            return;

        if (TrackList[index] is not { } item)
            return;

        StartPlaying(item);
    }

    private void StopPlaying()
    {
        StopPlayingRequest?.Invoke();
        ResetTrackIndicators();
        UpdateFileRemoveButton();
    }

    private void StartPlaying(ItemList.Item item)
    {
        if (item.Metadata is not ResPath resPath)
            return;

        if (item.Text == null)
            return;

        _timeSinceLastRecoverAttempt = 0;
        var midiData = _midiCollection.GetMidiData(resPath);
        StartPlayingRequest?.Invoke(midiData);
        CurrentTrackLabel.Text = item.Text;
        UpdateFileRemoveButton();
    }

    private void FilterTrackList()
    {
        var filterString = CurrentFilter.Trim().ToLowerInvariant();
        TrackList.Clear();

        foreach (var track in _loadedTracks)
        {
            var trackName = track.FilenameWithoutExtension.Trim().ToLowerInvariant();
            if (trackName.Contains(filterString))
                TrackList.AddItem(track.FilenameWithoutExtension, null, true, track);
        }
    }

    private bool TryGetSelectedTrackPath([NotNullWhen(true)] out ResPath? trackPath)
    {
        trackPath = null;
        if (!TryGetSelectedTrack(out var item) || item.Metadata is not ResPath resPath)
            return false;

        trackPath = resPath;
        return true;
    }

    private bool TryGetSelectedTrack([NotNullWhen(true)] out ItemList.Item? item)
    {
        return TrackList.GetSelected().TryFirstOrDefault(out item);
    }

    private void AddTrack(ResPath trackPath)
    {
        _loadedTracks.Add(trackPath);
        FilterTrackList();
    }

    private void RemoveTrack(ResPath trackPath)
    {
        _loadedTracks.Remove(trackPath);
        FilterTrackList();
    }

    private void ReloadTrackList()
    {
        _loadedTracks.Clear();
        _loadedTracks.AddRange(_midiCollection.GetMidiFiles());
        FilterTrackList();
    }

    private void ReplayCurrentTrack()
    {
        if (!TryGetSelectedTrack(out var track))
            return;

        StartPlaying(track);
    }

    /// <summary>
    /// Selects the next MIDI track from the list according to shuffle and filter settings.
    /// </summary>
    /// <remarks>Selecting another track causes its playback if <see cref="IsPlaying" /> is true.</remarks>
    public void SelectNextTrack()
    {
        // Only proceed if file panel is active.
        if (!Enabled)
            return;

        // Only proceed if the play button is pressed.
        if (!IsPlaying)
            return;

        // List is empty, return
        if (TrackList.Count == 0)
            return;

        _selectedInternally = true;
        try
        {
            if (IsShuffle)
            {
                var randomIndex = _random.Next(0, TrackList.Count);
                var randomTrack = TrackList[randomIndex];
                if (randomTrack.Selected)
                {
                    // Try going one up or down if we roll the already selected track.
                    if (TrackList.Count - 1 > randomIndex)
                        TrackList[randomIndex + 1].Selected = true;
                    else if (randomIndex > 0)
                        TrackList[randomIndex - 1].Selected = true;
                    else
                        randomTrack.Selected = true;
                }
                else
                {
                    randomTrack.Selected = true;
                }
            }
            else
            {
                if (!TryGetSelectedTrack(out var item))
                {
                    TrackList[0].Selected = true;
                    return;
                }

                for (var i = 0; i < TrackList.Count - 1; i++)
                {
                    if (TrackList[i] != item)
                        continue;
                    TrackList[i + 1].Selected = true;
                    return;
                }

                TrackList[0].Selected = false;
                TrackList[0].Selected = true;
            }
        }
        finally
        {
            _selectedInternally = false;
        }
    }
}