HymnalProjector/Projector/FrmMain.cs

using NAudio.Wave;
using System;
using System.Windows.Forms;
using YoutubeExplode;
using YoutubeExplode.Videos;
using YoutubeExplode.Videos.Streams;

namespace Projector
{
    public partial class FrmMain : Form
    {
        private Video? _video = null;
        private StreamManifest? _streamManifest = null;
        FourChannelToStereoSampleProvider? mixer = null;
        string musicPath = "C:\\Hymnal\\Music";
        string editsPath = "C:\\Hymnal\\Edits";
        string LyricsPath = "C:\\Hymnal\\Lyrics";
        FrmPreview frmPreview = new FrmPreview();

        public FrmMain()
        {
            InitializeComponent();

            DgvHymns.CellContentClick += DgvHymns_CellContentClick;
        }

        private void FrmMain_Load(object sender, EventArgs e)
        {
            FrmMain_Resize(null, null);

            if (!System.IO.Directory.Exists(musicPath))
            {
                MessageBox.Show("Hymns directory does not exist: " + musicPath);
                return;
            }

            var hymns = System.IO.Directory.GetFiles(musicPath, "*.m4a");
            foreach (var hymn in hymns)
            {
                var fileName = System.IO.Path.GetFileNameWithoutExtension(hymn);
                DgvHymns.Rows.Add(fileName, "");
            }
        }

        private void DgvHymns_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
        {
            if (DgvHymns.Columns[e.ColumnIndex].Name == "CnPlay" && e.RowIndex >= 0)
            {
                e.Paint(e.CellBounds, DataGridViewPaintParts.All);
                var icon = Properties.Resources.Play; // Assuming you have a play icon in resources
                var iconRect = new Rectangle(e.CellBounds.X + 2, e.CellBounds.Y + 2, e.CellBounds.Height - 4, e.CellBounds.Height - 4);
                e.Graphics?.DrawImage(icon, iconRect);
                e.Handled = true; // Prevent default painting
            }
        }

        // 3. Handle the Play button click:
        private void DgvHymns_CellContentClick(object sender, DataGridViewCellEventArgs e)
        {
            // Check if PlayButton column and not header row
            if (e.RowIndex >= 0 && DgvHymns.Columns[e.ColumnIndex].Name == "CnPlay")
            {
                var hymnName = DgvHymns.Rows[e.RowIndex].Cells["CnHymn"].Value?.ToString();
                if (!string.IsNullOrEmpty(hymnName))
                {
                    PlayHymn(hymnName);
                }
            }
        }

        private void PlayHymn(string name)
        {
            string audioFilePath = Path.Combine(editsPath, name + ".m4a");
            if (!File.Exists(audioFilePath))
            {
                audioFilePath = Path.Combine(musicPath, name + ".m4a");
            }

            string number = name.Substring(0, 3).Trim(); // Extract the first 3 characters

            try
            {
                // Open the audio file
                var reader = new MediaFoundationReader(audioFilePath);

                // Check for 4 channels
                if (reader.WaveFormat.Channels != 4)
                {
                    MessageBox.Show("Audio file does not have 4 channels.");
                    reader.Dispose();
                    return;
                }

                // Create a custom sample provider to mix channels 0+2 to left, 1+3 to right
                mixer = new FourChannelToStereoSampleProvider(reader.ToSampleProvider());

                // Search the folder in LyricsPath that starts with the hymn number
                string lyricsFilePath = Directory.GetDirectories(LyricsPath).ToList().ConvertAll(d => Path.GetFileName(d))
                    .FirstOrDefault(dir => dir.StartsWith(number, StringComparison.OrdinalIgnoreCase));

                // Get all the jpg files in the lyrics folder
                if (lyricsFilePath != null)
                {
                    string lyricsFolderPath = Path.Combine(LyricsPath, lyricsFilePath);
                    var jpgFiles = Directory.GetFiles(lyricsFolderPath, "*.jpg");

                    // Order the jpg files by name
                    Array.Sort(jpgFiles, StringComparer.OrdinalIgnoreCase);

                    // Display the first jpg file in a PictureBox or similar control
                    if (jpgFiles.Length > 0)
                    {
                        // Assuming you have a PictureBox named pictureBoxLyrics
                        frmPreview.SetImages(jpgFiles, mixer);
                    }
                }

                var waveOut = new WaveOutEvent();
                waveOut.Init(mixer);
                waveOut.Play();
                frmPreview.ShowDialog(this);
                TbFilter.SelectAll();
                TbFilter.Focus();

                // Crate a task to handle the transition
                Task.Run(() =>
                {
                    mixer.SetOff();
                    while (!mixer.IsOff)
                    {
                        Thread.Sleep(100); // Check every 100ms
                    }
                    waveOut.Stop();
                });

                // Optionally, store waveOut and reader as fields to stop/dispose later
            }
            catch (Exception ex)
            {
                MessageBox.Show("Error playing audio: " + ex.Message);
            }
        }

        private void TbFilter_TextChanged(object sender, EventArgs e)
        {
            // Filter the DataGridView based on the text in the filter TextBox
            string filterText = TbFilter.Text.ToLower();
            foreach (DataGridViewRow row in DgvHymns.Rows)
            {
                if (row.Cells["CnHymn"].Value != null)
                {
                    row.Visible = row.Cells["CnHymn"].Value.ToString().ToLower().Contains(filterText);
                }
            }

            var visibleRows = DgvHymns.Rows
                .Cast<DataGridViewRow>()
                .Where(row => row.Visible)
                .ToList();
            if (visibleRows.Count > 0)
            {
                int firstVisibleRowIndex = visibleRows[0].Index;
                DgvHymns.Rows[firstVisibleRowIndex].Selected = true;
                DgvHymns.FirstDisplayedScrollingRowIndex = firstVisibleRowIndex;
            }
        }

        private void FrmMain_Resize(object sender, EventArgs e)
        {
            DgvHymns.Columns["CnHymn"].Width = Width - 80;
        }

        protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
        {
            if (keyData == Keys.Down)
            {
                var visibleRows = DgvHymns.Rows
                    .Cast<DataGridViewRow>()
                    .Where(row => row.Visible)
                    .ToList();

                if (visibleRows.Count > 0)
                {
                    int selectedRowIndex = visibleRows.FindIndex(row => row.Selected);
                    selectedRowIndex++;
                    if (selectedRowIndex < visibleRows.Count)
                    {
                        visibleRows[selectedRowIndex].Selected = true;

                        int firstDisplayed = DgvHymns.FirstDisplayedScrollingRowIndex;
                        int displayedCount = DgvHymns.DisplayedRowCount(false); // false = only fully visible rows
                        int lastDisplayed = firstDisplayed + displayedCount - 1;
                        if (selectedRowIndex >= lastDisplayed)
                        {
                            DgvHymns.FirstDisplayedScrollingRowIndex = visibleRows[selectedRowIndex - displayedCount + 1].Index;
                        }
                    }
                }

                return true;
            }
            else if (keyData == Keys.Up)
            {
                var visibleRows = DgvHymns.Rows
                    .Cast<DataGridViewRow>()
                    .Where(row => row.Visible)
                    .ToList();

                if (visibleRows.Count > 0)
                {
                    int selectedRowIndex = visibleRows.FindIndex(row => row.Selected);
                    selectedRowIndex--;
                    if (selectedRowIndex >= 0)
                    {
                        visibleRows[selectedRowIndex].Selected = true;

                        int firstDisplayed = DgvHymns.FirstDisplayedScrollingRowIndex;
                        int displayedCount = DgvHymns.DisplayedRowCount(false); // false = only fully visible rows

                        if (selectedRowIndex < firstDisplayed)
                        {
                            DgvHymns.FirstDisplayedScrollingRowIndex = visibleRows[selectedRowIndex].Index;
                        }
                    }
                }

                return true;
            }
            else if (keyData == Keys.Enter)
            {
                // Handle Enter key to simulate Play button click
                var selectedRow = DgvHymns.SelectedRows.Cast<DataGridViewRow>().FirstOrDefault();
                if (selectedRow != null && selectedRow.Cells["CnPlay"].Value != null)
                {
                    DgvHymns_CellContentClick(sender: null, e: new DataGridViewCellEventArgs(1, selectedRow.Index));
                    return true; // Indicate that the key press has been handled
                }
            }
            else if (keyData == Keys.Home)
            {
                var visibleRows = DgvHymns.Rows
                    .Cast<DataGridViewRow>()
                    .Where(row => row.Visible)
                    .ToList();

                if (visibleRows.Count > 0)
                { 
                    visibleRows.First().Selected = true;
                    int selectedRowIndex = visibleRows.First().Index;

                    int firstDisplayed = DgvHymns.FirstDisplayedScrollingRowIndex;
                    int displayedCount = DgvHymns.DisplayedRowCount(false); // false = only fully visible rows

                    if (selectedRowIndex < firstDisplayed)
                    {
                        DgvHymns.FirstDisplayedScrollingRowIndex = visibleRows[selectedRowIndex].Index;
                    }
                }
                return true; // Indicate that the key press has been handled
            }
            else if (keyData == Keys.End)
            {
                var visibleRows = DgvHymns.Rows
                    .Cast<DataGridViewRow>()
                    .Where(row => row.Visible)
                    .ToList();

                if (visibleRows.Count > 0)
                {
                    visibleRows.Last().Selected = true;
                    int selectedRowIndex = visibleRows.Last().Index;

                    int firstDisplayed = DgvHymns.FirstDisplayedScrollingRowIndex;
                    int displayedCount = DgvHymns.DisplayedRowCount(false); // false = only fully visible rows
                    int lastDisplayed = firstDisplayed + displayedCount - 1;
                    if (selectedRowIndex >= lastDisplayed)
                    {
                        DgvHymns.FirstDisplayedScrollingRowIndex = visibleRows[selectedRowIndex - displayedCount + 1].Index;
                    }
                }

                return true; // Indicate that the key press has been handled
            }

            return base.ProcessCmdKey(ref msg, keyData); // Allow default processing if not an arrow key
        }
    }
}