SettingsForm.cs

// Copyright (c) 2012-2026 The Hello World Writer (https://www.thehelloworldwriter.com).
// Licensed under the MIT License. See the LICENSE file in the project root for more information.

namespace GridlyDots;

/// <summary>Settings dialog for adjusting the grid overlay properties in real time.</summary>
public class SettingsForm : Form
{
    /// <summary>Near-black color that avoids conflict with the pure Black transparency key.</summary>
    private static readonly Color SafeBlack = Color.FromArgb(1, 1, 1);

    private readonly Label dotSizeLabel = new() { Dock = DockStyle.Fill, TextAlign = ContentAlignment.MiddleLeft };
    private readonly Label dotSpacingLabel = new() { Dock = DockStyle.Fill, TextAlign = ContentAlignment.MiddleLeft };
    private readonly Label gridOpacityLabel = new() { Dock = DockStyle.Fill, TextAlign = ContentAlignment.MiddleLeft };
    private readonly TrackBar dotSizeTrackBar = new();
    private readonly TrackBar dotSpacingTrackBar = new();
    private readonly TrackBar gridOpacityTrackBar = new();
    private readonly Button dotColorButton = new();
    private readonly ColorDialog colorDialog = new();

    public SettingsForm()
    {
        SuspendLayout();

        // Dimensions BEFORE mode (setting the mode clears dimensions)
        AutoScaleDimensions = new SizeF(96F, 96F);
        AutoScaleMode = AutoScaleMode.Dpi;

        Text = Strings.SettingsBoxTitle;
        FormBorderStyle = FormBorderStyle.FixedDialog;
        StartPosition = FormStartPosition.CenterParent;
        MinimizeBox = false;
        MaximizeBox = false;
        TopMost = true;
        KeyPreview = true;
        BackColor = SystemColors.Window;
        AutoSize = true;
        AutoSizeMode = AutoSizeMode.GrowAndShrink;
        MinimumSize = new Size(480, 0);
        Padding = new Padding(20);

        CreateControls();

        Load += OnFormLoad;

        ResumeLayout(false);
        PerformLayout();
    }

    /// <summary>Builds the UI control tree and adds it to the form.</summary>
    private void CreateControls()
    {
        // TableLayoutPanel — 2 columns (labels 35%, sliders 65%), 5 rows
        var layout = new TableLayoutPanel
        {
            ColumnCount = 2,
            RowCount = 5,
            AutoSize = true,
            AutoSizeMode = AutoSizeMode.GrowAndShrink,
            Dock = DockStyle.Fill,
        };
        layout.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 35F));
        layout.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 65F));
        layout.RowStyles.Add(new RowStyle(SizeType.AutoSize));
        layout.RowStyles.Add(new RowStyle(SizeType.AutoSize));
        layout.RowStyles.Add(new RowStyle(SizeType.AutoSize));
        layout.RowStyles.Add(new RowStyle(SizeType.AutoSize));
        layout.RowStyles.Add(new RowStyle(SizeType.AutoSize));

        // Row 0: Dot size
        ConfigureTrackBar(dotSizeTrackBar, 1, 100, 10);
        dotSizeTrackBar.Scroll += OnDotSizeScroll;
        layout.Controls.Add(dotSizeLabel, 0, 0);
        layout.Controls.Add(dotSizeTrackBar, 1, 0);

        // Row 1: Dot spacing
        ConfigureTrackBar(dotSpacingTrackBar, 0, 100, 10);
        dotSpacingTrackBar.Scroll += OnDotSpacingScroll;
        layout.Controls.Add(dotSpacingLabel, 0, 1);
        layout.Controls.Add(dotSpacingTrackBar, 1, 1);

        // Row 2: Grid opacity
        ConfigureTrackBar(gridOpacityTrackBar, 0, 100, 10);
        gridOpacityTrackBar.Scroll += OnGridOpacityScroll;
        layout.Controls.Add(gridOpacityLabel, 0, 2);
        layout.Controls.Add(gridOpacityTrackBar, 1, 2);

        // Row 3: Dot color
        var dotColorLabel = new Label
        {
            Text = Strings.DotColor,
            Dock = DockStyle.Fill,
            TextAlign = ContentAlignment.MiddleLeft,
        };
        dotColorButton.Size = AppConstants.ButtonMinimumSize;
        dotColorButton.UseVisualStyleBackColor = false;
        dotColorButton.Anchor = AnchorStyles.Left;
        dotColorButton.Click += OnDotColorClick;
        layout.Controls.Add(dotColorLabel, 0, 3);
        layout.Controls.Add(dotColorButton, 1, 3);

        // Row 4: Close button
        var closeButton = new Button
        {
            Text = Strings.CloseButton,
            DialogResult = DialogResult.Cancel,
            MinimumSize = AppConstants.ButtonMinimumSize,
            Anchor = AnchorStyles.Right,
        };
        CancelButton = closeButton;
        layout.Controls.Add(closeButton, 1, 4);

        Controls.Add(layout);
    }

    /// <summary>Configures a TrackBar with common settings.</summary>
    private static void ConfigureTrackBar(TrackBar trackBar, int min, int max, int tickFrequency)
    {
        trackBar.Minimum = min;
        trackBar.Maximum = max;
        trackBar.TickFrequency = tickFrequency;
        trackBar.TickStyle = TickStyle.None;
        trackBar.AutoSize = false;
        trackBar.Height = 30;
        trackBar.Margin = new Padding(3, 8, 3, 8);
        trackBar.Anchor = AnchorStyles.Left | AnchorStyles.Right;
    }

    /// <summary>Loads current settings from the grid form and updates the controls.</summary>
    private void OnFormLoad(object? sender, EventArgs e)
    {
        ApplyToGridForm(form =>
        {
            dotSizeTrackBar.Value = form.GPainter.DotSize;
            dotSpacingTrackBar.Value = form.GPainter.DotSpacing;
            gridOpacityTrackBar.Value = (int)(form.Opacity * 100);
            dotColorButton.BackColor = form.GPainter.DotColor;
        });

        UpdateLabels();
    }

    /// <summary>Executes an action on the owner GridForm and invalidates it to repaint the grid.</summary>
    private void ApplyToGridForm(Action<GridForm> action)
    {
        if (Owner is GridForm gridForm)
        {
            action(gridForm);
            gridForm.Invalidate();
        }
    }

    /// <summary>Updates all setting labels with current track bar values.</summary>
    private void UpdateLabels()
    {
        dotSizeLabel.Text = Strings.DotSize(dotSizeTrackBar.Value);
        dotSpacingLabel.Text = Strings.DotSpacing(dotSpacingTrackBar.Value);
        gridOpacityLabel.Text = Strings.GridOpacity(gridOpacityTrackBar.Value);
    }

    /// <summary>Applies the dot size change to the grid and updates the label.</summary>
    private void OnDotSizeScroll(object? sender, EventArgs e)
    {
        ApplyToGridForm(form => form.GPainter.DotSize = dotSizeTrackBar.Value);
        dotSizeLabel.Text = Strings.DotSize(dotSizeTrackBar.Value);
    }

    /// <summary>Applies the dot spacing change to the grid and updates the label.</summary>
    private void OnDotSpacingScroll(object? sender, EventArgs e)
    {
        ApplyToGridForm(form => form.GPainter.DotSpacing = dotSpacingTrackBar.Value);
        dotSpacingLabel.Text = Strings.DotSpacing(dotSpacingTrackBar.Value);
    }

    /// <summary>Applies the opacity change to the grid and updates the label.</summary>
    private void OnGridOpacityScroll(object? sender, EventArgs e)
    {
        ApplyToGridForm(form => form.Opacity = gridOpacityTrackBar.Value / 100.0);
        gridOpacityLabel.Text = Strings.GridOpacity(gridOpacityTrackBar.Value);
    }

    /// <summary>Opens the color picker and applies the selected color, substituting near-black for pure black.</summary>
    private void OnDotColorClick(object? sender, EventArgs e)
    {
        colorDialog.Color = dotColorButton.BackColor;
        if (colorDialog.ShowDialog() != DialogResult.OK)
        {
            return;
        }

        // Pure black would be invisible (matches the grid form's TransparencyKey)
        Color color = colorDialog.Color == Color.Black ? SafeBlack : colorDialog.Color;
        ApplyToGridForm(form => form.GPainter.DotColor = color);
        dotColorButton.BackColor = color;
    }

    /// <summary>Disposes components not in the Controls hierarchy.</summary>
    protected override void Dispose(bool disposing)
    {
        if (disposing)
        {
            colorDialog.Dispose();
        }

        base.Dispose(disposing);
    }
}