using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Avalonia.Controls;
using Avalonia.Input;
using Avalonia.Platform.Storage;
using SlamCross.ViewModels;

namespace SlamCross.Views;

public partial class MainWindow : Window
{
    private MainWindowViewModel Vm => (MainWindowViewModel)DataContext!;

    public MainWindow()
    {
        InitializeComponent();
        DataContext = new MainWindowViewModel();
        Vm.ErrorOccurred += msg => Avalonia.Threading.Dispatcher.UIThread.Post(() => ShowMessage(msg));
        Closing += (_, e) => { Vm.StopPoll(); Vm.StopStream(); Vm.SaveSettings(); };
        if (Vm.Settings.StartMinimized)
            WindowState = WindowState.Minimized;
    }

    private async void ShowMessage(string msg)
    {
        var ok = new Button { Content = "OK", HorizontalAlignment = Avalonia.Layout.HorizontalAlignment.Right };
        var dlg = new Window
        {
            Title = "SLAM",
            Width = 400,
            Height = 150,
            Content = new StackPanel
            {
                Margin = new Avalonia.Thickness(16),
                Spacing = 12,
                Children =
                {
                    new TextBlock { Text = msg, TextWrapping = Avalonia.Media.TextWrapping.Wrap },
                    ok
                }
            }
        };
        ok.Click += (_, _) => dlg.Close();
        await dlg.ShowDialog(this);
    }

    private async void ImportButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var files = await StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
        {
            Title = "Import Audio Files",
            AllowMultiple = true,
            FileTypeFilter = new[]
            {
                new FilePickerFileType("Audio/Video")
                {
                    Patterns = new[] { "*.mp3","*.wav","*.aac","*.wma","*.m4a","*.mp4","*.wmv","*.avi","*.m4v","*.mov","*.flac","*.ogg" }
                }
            }
        });
        if (files.Count > 0)
            await Vm.ImportFilesAsync(files.Select(f => f.Path.LocalPath));
    }

    private async void YTButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var dlg = new YTImportWindow();
        await dlg.ShowDialog(this);
        if (dlg.ResultUrl is string url)
            await DownloadAndImportYt(url);
    }

    private async Task DownloadAndImportYt(string url)
    {
        var tmpDir = Path.Combine(Path.GetTempPath(), "slam_yt");
        Directory.CreateDirectory(tmpDir);
        var outTemplate = Path.Combine(tmpDir, "%(title)s.%(ext)s");

        var psi = new ProcessStartInfo("yt-dlp")
        {
            UseShellExecute = false,
            CreateNoWindow = true
        };
        psi.ArgumentList.Add("-x");
        psi.ArgumentList.Add("--audio-format"); psi.ArgumentList.Add("mp3");
        psi.ArgumentList.Add("-o"); psi.ArgumentList.Add(outTemplate);
        psi.ArgumentList.Add(url);
        try
        {
            using var proc = Process.Start(psi);
            if (proc != null) await proc.WaitForExitAsync();
        }
        catch
        {
            Vm.ShowError("yt-dlp not found. Install it to import from YouTube.");
            return;
        }

        var downloaded = Directory.GetFiles(tmpDir);
        if (downloaded.Length > 0)
            await Vm.ImportFilesAsync(downloaded, deleteSource: true);

        try { Directory.Delete(tmpDir, true); } catch { }
    }

    private async void SettingsButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var dlg = new SettingsWindow(Vm.Settings);
        await dlg.ShowDialog(this);
        Vm.SaveSettings();
    }

    private async void PlayKeyButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var dlg = new SelectKeyWindow();
        await dlg.ShowDialog(this);
        if (dlg.ChosenKey is string key)
            Vm.SetPlayKey(key);
    }

    private void StartStopButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        if (Vm.IsRunning) Vm.StopPoll();
        else _ = Vm.StartPollAsync();
    }

    private void StreamButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        if (Vm.IsStreaming) { Vm.StopStream(); return; }
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) { Vm.ShowError("Select a track first."); return; }
        Vm.StreamToMic(idx);
    }

    private void StopStreamButton_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
        => Vm.StopStream();

    private void TrackGrid_DoubleTapped(object? sender, TappedEventArgs e)
    {
        var selected = GetSelectedIndices().FirstOrDefault(-1);
        if (selected < 0) return;
        if (Vm.IsRunning)
            Vm.PlayTrack(selected);
        else
            Vm.StreamToMic(selected);
    }

    private void MenuPlay_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) return;
        if (Vm.IsRunning) Vm.PlayTrack(idx);
        else Vm.StreamToMic(idx);
    }

    private void MenuRefresh_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
        => Vm.RefreshTracks();

    private async void MenuHotkey_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) return;
        var dlg = new SelectKeyWindow();
        await dlg.ShowDialog(this);
        if (dlg.ChosenKey is string key)
            Vm.SetTrackHotkey(idx, key);
    }

    private void MenuRemoveHotkey_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        foreach (var idx in GetSelectedIndices())
            Vm.RemoveHotkey(idx);
    }

    private async void MenuVolume_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var indices = GetSelectedIndices().ToList();
        if (indices.Count == 0) return;
        var dlg = new SetVolumeWindow();
        await dlg.ShowDialog(this);
        if (dlg.Volume >= 0)
            Vm.SetTrackVolume(indices, dlg.Volume);
    }

    private async void MenuTrim_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) return;
        var track = Vm.GetTrack(idx);
        if (track == null) return;
        var filePath = Vm.GetTrackFilePath(idx);
        var dlg = new TrimWindow(filePath, track.StartPos, track.EndPos);
        await dlg.ShowDialog(this);
        if (dlg.Confirmed)
            Vm.SetTrackTrim(idx, dlg.StartPos, dlg.EndPos);
    }

    private async void MenuRename_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) return;
        var track = Vm.GetTrack(idx);
        if (track == null) return;
        var dlg = new RenameWindow(track.Name);
        await dlg.ShowDialog(this);
        if (dlg.NewName is string name)
            Vm.RenameTrack(idx, name);
    }

    private void MenuGoTo_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var idx = GetSelectedIndices().FirstOrDefault(-1);
        if (idx < 0) return;
        var path = Vm.GetTrackFilePath(idx);
        if (!File.Exists(path)) return;
        var dir = Path.GetDirectoryName(path)!;
        if (System.Runtime.InteropServices.RuntimeInformation.IsOSPlatform(
            System.Runtime.InteropServices.OSPlatform.Linux))
            Process.Start("xdg-open", dir);
        else
            Process.Start("explorer.exe", $"/select,\"{path}\"");
    }

    private async void MenuDelete_Click(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
    {
        var indices = GetSelectedIndices().ToList();
        if (indices.Count == 0) return;
        var names = indices.Select(i => Vm.Tracks[i].Name);
        var confirm = new ConfirmWindow($"Delete {string.Join(", ", names)}?");
        await confirm.ShowDialog(this);
        if (confirm.Confirmed)
            Vm.DeleteTracks(indices);
    }

    private IEnumerable<int> GetSelectedIndices()
    {
        var grid = this.FindControl<DataGrid>("TrackGrid");
        if (grid == null) yield break;
        foreach (var item in grid.SelectedItems.OfType<TrackItem>())
            yield return item.Index;
    }
}