using System.Diagnostics;
using System.Drawing.Drawing2D;
using System.Runtime.Versioning;

namespace DevDrive;

/// <summary>
/// Retro-styled dialog that prompts the user to select which startup apps to launch.
/// </summary>
[SupportedOSPlatform("windows")]
public class StartupDialog : Form
{
    private static readonly Color BackgroundDark = Color.FromArgb(24, 24, 32);
    private static readonly Color BackgroundMid = Color.FromArgb(32, 32, 44);
    private static readonly Color AccentCyan = Color.FromArgb(0, 255, 255);
    private static readonly Color AccentMagenta = Color.FromArgb(255, 0, 128);
    private static readonly Color TextLight = Color.FromArgb(240, 240, 255);
    private static readonly Color TextDim = Color.FromArgb(140, 140, 160);
    private static readonly Color BorderColor = Color.FromArgb(60, 60, 80);

    private readonly List<StartupApp> _apps;
    private readonly List<RetroCheckBox> _checkboxes = [];
    private readonly string _driveName;
    private readonly System.Windows.Forms.Timer _animTimer;
    private float _scanlineOffset;
    private float _glowPulse;
    private float _flickerTarget;
    private float _flickerCurrent;
    private float _brightLineY;
    private int _flickerCounter;

    /// <summary>
    /// Creates a new startup dialog for the given apps.
    /// </summary>
    public StartupDialog(List<StartupApp> apps, string driveName)
    {
        _apps = apps;
        _driveName = driveName;

        SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);

        Text = "STARTUP";
        FormBorderStyle = FormBorderStyle.None;
        StartPosition = FormStartPosition.CenterScreen;
        BackColor = BackgroundDark;
        Opacity = 0.86;

        var itemHeight = 44;
        var headerHeight = 60;
        var footerHeight = 70;
        var padding = 20;
        var contentWidth = 380;

        var contentHeight = headerHeight + (_apps.Count * itemHeight) + footerHeight;
        ClientSize = new Size(contentWidth, contentHeight);

        // Set the window region to rounded rectangle for transparent corners
        UpdateWindowRegion();

        var yPos = headerHeight;

        foreach (var app in _apps)
        {
            var checkbox = new RetroCheckBox
            {
                Text = app.Name,
                Tag = app,
                Checked = app.CheckedByDefault,
                Location = new Point(padding, yPos),
                Size = new Size(contentWidth - (padding * 2), itemHeight - 4)
            };

            _checkboxes.Add(checkbox);
            Controls.Add(checkbox);
            yPos += itemHeight;
        }

        var buttonWidth = 110;
        var buttonHeight = 36;
        var buttonY = contentHeight - footerHeight + 17;

        var launchButton = new RetroButton
        {
            Text = "► LAUNCH",
            Location = new Point(contentWidth - padding - buttonWidth - 12 - buttonWidth, buttonY),
            Size = new Size(buttonWidth, buttonHeight),
            IsPrimary = true
        };
        launchButton.Click += (s, e) => { LaunchSelectedApps(); Close(); };
        Controls.Add(launchButton);

        var skipButton = new RetroButton
        {
            Text = "SKIP",
            Location = new Point(contentWidth - padding - buttonWidth, buttonY),
            Size = new Size(buttonWidth, buttonHeight),
            IsPrimary = false
        };
        skipButton.Click += (s, e) => Close();
        Controls.Add(skipButton);

        _animTimer = new System.Windows.Forms.Timer { Interval = 50 };
        _animTimer.Tick += OnAnimTick;
        _animTimer.Start();
    }

    private void OnAnimTick(object? sender, EventArgs e)
    {
        _scanlineOffset = (_scanlineOffset + 0.3f) % 6f;

        _glowPulse = (float)(Math.Sin(Environment.TickCount / 800.0) * 20 + 20);

        _brightLineY = (_brightLineY + 1.5f) % (Height + 40);

        _flickerCounter++;
        if (_flickerCounter >= 8)
        {
            _flickerCounter = 0;
            _flickerTarget = Random.Shared.Next(0, 5);
        }
        _flickerCurrent += (_flickerTarget - _flickerCurrent) * 0.3f;

        Invalidate();
    }

    protected override void OnFormClosed(FormClosedEventArgs e)
    {
        _animTimer.Stop();
        _animTimer.Dispose();
        base.OnFormClosed(e);
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);
        var g = e.Graphics;
        g.SmoothingMode = SmoothingMode.AntiAlias;

        // Apply subtle bulge transformation
        var centerX = Width / 2f;
        var centerY = Height / 2f;
        var bulgeStrength = 0.08f;
        
        // Create a slight perspective transform for CRT bulge
        var scaleX = 1.0f - bulgeStrength;
        var scaleY = 1.0f - bulgeStrength;
        
        g.TranslateTransform(centerX, centerY);
        g.ScaleTransform(scaleX + bulgeStrength, scaleY + bulgeStrength);
        g.TranslateTransform(-centerX, -centerY);

        using var backgroundBrush = new SolidBrush(Color.FromArgb(240, BackgroundDark));
        g.FillRectangle(backgroundBrush, 0, 0, Width, Height);

        var glowAlpha = (int)(180 + _glowPulse);
        var pulsingCyan = Color.FromArgb(Math.Min(255, glowAlpha), 0, 255, 255);

        // Inner content
        DrawContent(g, pulsingCyan);

        // Reset transform for effects
        g.ResetTransform();

        // CRT bezel effect - subtle outer shadow
        using var bezelBrush = new LinearGradientBrush(
            new Rectangle(0, 0, Width, Height),
            Color.FromArgb(60, 0, 0, 0),
            Color.Transparent,
            LinearGradientMode.Vertical);
        
        var screenRect = new Rectangle(3, 3, Width - 6, Height - 6);
        using var screenPath = CreateRoundedRectangle(screenRect, 12);
        
        var bezelRect = new Rectangle(0, 0, Width, Height);
        using var outerPath = CreateRoundedRectangle(bezelRect, 16);
        using var innerPath = CreateRoundedRectangle(new Rectangle(4, 4, Width - 8, Height - 8), 10);
        
        var bezelRegion = new Region(outerPath);
        bezelRegion.Exclude(innerPath);
        g.FillRegion(bezelBrush, bezelRegion);

        // Outer glow
        using var outerGlow = new Pen(Color.FromArgb((int)(20 + _glowPulse / 2), AccentCyan), 3);
        g.DrawPath(outerGlow, CreateRoundedRectangle(new Rectangle(1, 1, Width - 2, Height - 2), 14));

        // Main border
        using var borderPen = new Pen(pulsingCyan, 2);
        g.DrawPath(borderPen, screenPath);

        // Corner reflections for glass effect
        DrawCRTReflections(g);
    }

    private void UpdateWindowRegion()
    {
        using var path = CreateRoundedRectangle(new Rectangle(0, 0, Width, Height), 16);
        Region = new Region(path);
    }

    protected override void OnResize(EventArgs e)
    {
        base.OnResize(e);
        UpdateWindowRegion();
    }

    private void DrawContent(Graphics g, Color pulsingCyan)
    {

        using var headerBrush = new LinearGradientBrush(
            new Rectangle(0, 0, Width, 60),
            Color.FromArgb((int)(40 + _glowPulse / 2), AccentCyan),
            Color.FromArgb(5, AccentCyan),
            LinearGradientMode.Vertical);
        g.FillRectangle(headerBrush, 5, 5, Width - 10, 55);

        using var titleFont = new Font("Consolas", 14, FontStyle.Bold);
        using var titleBrush = new SolidBrush(pulsingCyan);
        var title = $"▸ {_driveName.ToUpper()}";
        g.DrawString(title, titleFont, titleBrush, 20, 15);

        using var subtitleFont = new Font("Consolas", 9);
        using var subtitleBrush = new SolidBrush(TextDim);
        g.DrawString("Select applications to launch", subtitleFont, subtitleBrush, 20, 38);

        using var linePen = new Pen(BorderColor, 1);
        g.DrawLine(linePen, 10, 58, Width - 10, 58);

        var footerY = Height - 70;
        g.DrawLine(linePen, 10, footerY, Width - 10, footerY);

        var scanOffset = (int)_scanlineOffset;
        for (var y = scanOffset; y < Height; y += 3)
        {
            var scanAlpha = 10 + (y % 6 == scanOffset ? 5 : 0);
            using var scanlinePen = new Pen(Color.FromArgb(scanAlpha, 0, 0, 0), 1);
            g.DrawLine(scanlinePen, 0, y, Width, y);
        }

        var brightY = (int)_brightLineY - 20;
        if (brightY >= 0 && brightY < Height)
        {
            using var brightScanline = new Pen(Color.FromArgb(12, 255, 255, 255), 3);
            g.DrawLine(brightScanline, 0, brightY, Width, brightY);
        }

        var flickerAlpha = (int)_flickerCurrent;
        if (flickerAlpha > 0)
        {
            using var flickerBrush = new SolidBrush(Color.FromArgb(flickerAlpha, 255, 255, 255));
            g.FillRectangle(flickerBrush, 0, 0, Width, Height);
        }
    }

    private GraphicsPath CreateRoundedRectangle(Rectangle rect, int radius)
    {
        var path = new GraphicsPath();
        var diameter = radius * 2;
        
        path.AddArc(rect.X, rect.Y, diameter, diameter, 180, 90);
        path.AddArc(rect.Right - diameter, rect.Y, diameter, diameter, 270, 90);
        path.AddArc(rect.Right - diameter, rect.Bottom - diameter, diameter, diameter, 0, 90);
        path.AddArc(rect.X, rect.Bottom - diameter, diameter, diameter, 90, 90);
        path.CloseFigure();
        
        return path;
    }

    private void DrawCRTReflections(Graphics g)
    {
        // Top-left corner reflection
        using var reflection1 = new LinearGradientBrush(
            new Rectangle(8, 8, 60, 40),
            Color.FromArgb(25, 255, 255, 255),
            Color.Transparent,
            45f);
        using var reflectPath1 = CreateRoundedRectangle(new Rectangle(8, 8, 60, 40), 8);
        g.FillPath(reflection1, reflectPath1);

        // Subtle center highlight
        using var reflection2 = new LinearGradientBrush(
            new Rectangle(Width / 4, 15, Width / 2, 25),
            Color.FromArgb(8, 255, 255, 255),
            Color.Transparent,
            LinearGradientMode.Vertical);
        using var reflectPath2 = CreateRoundedRectangle(new Rectangle(Width / 4, 15, Width / 2, 25), 4);
        g.FillPath(reflection2, reflectPath2);
    }

    private void LaunchSelectedApps()
    {
        foreach (var checkbox in _checkboxes)
        {
            if (!checkbox.Checked || checkbox.Tag is not StartupApp app)
            {
                continue;
            }

            try
            {
                var startInfo = new ProcessStartInfo
                {
                    FileName = Environment.ExpandEnvironmentVariables(app.Path),
                    UseShellExecute = true
                };

                if (!string.IsNullOrWhiteSpace(app.Arguments))
                {
                    startInfo.Arguments = Environment.ExpandEnvironmentVariables(app.Arguments);
                }

                if (!string.IsNullOrWhiteSpace(app.WorkingDirectory))
                {
                    startInfo.WorkingDirectory = Environment.ExpandEnvironmentVariables(app.WorkingDirectory);
                }

                Process.Start(startInfo);
                Console.WriteLine($"[DevDrive] Launched: {app.Name}");
            }
            catch (Exception ex)
            {
                Console.WriteLine($"[DevDrive] Failed to launch {app.Name}: {ex.Message}");
            }
        }
    }

    /// <summary>
    /// Shows the startup dialog if there are apps to display.
    /// </summary>
    public static void ShowIfNeeded(List<StartupApp> apps, string driveName)
    {
        if (apps.Count == 0)
        {
            return;
        }

        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        using var dialog = new StartupDialog(apps, driveName);
        dialog.ShowDialog();
    }

    protected override void OnMouseDown(MouseEventArgs e)
    {
        base.OnMouseDown(e);
        if (e.Button == MouseButtons.Left && e.Y < 60)
        {
            NativeMethods.ReleaseCapture();
            NativeMethods.SendMessage(Handle, 0xA1, 0x2, 0);
        }
    }

    private static class NativeMethods
    {
        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);

        [System.Runtime.InteropServices.DllImport("user32.dll")]
        public static extern bool ReleaseCapture();
    }
}

/// <summary>
/// Custom retro-styled checkbox control.
/// </summary>
[SupportedOSPlatform("windows")]
public class RetroCheckBox : Control
{
    private static readonly Color BackgroundDark = Color.FromArgb(24, 24, 32);
    private static readonly Color AccentCyan = Color.FromArgb(0, 255, 255);
    private static readonly Color AccentMagenta = Color.FromArgb(255, 0, 128);
    private static readonly Color TextLight = Color.FromArgb(240, 240, 255);
    private static readonly Color BorderColor = Color.FromArgb(60, 60, 80);

    private bool _checked;
    private bool _hovering;

    public bool Checked
    {
        get => _checked;
        set { _checked = value; Invalidate(); }
    }

    public RetroCheckBox()
    {
        SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);
        Size = new Size(200, 40);
        Cursor = Cursors.Hand;
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        var g = e.Graphics;
        g.SmoothingMode = SmoothingMode.AntiAlias;

        var bgColor = _hovering ? Color.FromArgb(200, 40, 40, 56) : Color.FromArgb(180, 28, 28, 40);
        using var bgBrush = new SolidBrush(bgColor);
        g.FillRectangle(bgBrush, 0, 0, Width, Height);

        var boxSize = 20;
        var boxX = 8;
        var boxY = (Height - boxSize) / 2;

        var boxBorderColor = _checked ? AccentCyan : BorderColor;
        using var boxPen = new Pen(boxBorderColor, _checked ? 2 : 1);
        g.DrawRectangle(boxPen, boxX, boxY, boxSize, boxSize);

        if (_checked)
        {
            using var checkBrush = new SolidBrush(AccentCyan);
            var innerPadding = 5;
            g.FillRectangle(checkBrush, boxX + innerPadding, boxY + innerPadding,
                boxSize - (innerPadding * 2) + 1, boxSize - (innerPadding * 2) + 1);

            using var glowPen = new Pen(Color.FromArgb(60, AccentCyan), 4);
            g.DrawRectangle(glowPen, boxX - 1, boxY - 1, boxSize + 2, boxSize + 2);
        }

        using var textFont = new Font("Consolas", 11, FontStyle.Bold);
        var textColor = _checked ? TextLight : Color.FromArgb(160, 160, 180);
        using var textBrush = new SolidBrush(textColor);
        var textX = boxX + boxSize + 14;
        var textY = (Height - textFont.Height) / 2;
        g.DrawString(Text, textFont, textBrush, textX, textY);

        if (_checked)
        {
            using var accentPen = new Pen(AccentCyan, 2);
            g.DrawLine(accentPen, 0, Height - 1, Width, Height - 1);
        }
    }

    protected override void OnMouseEnter(EventArgs e)
    {
        _hovering = true;
        Invalidate();
        base.OnMouseEnter(e);
    }

    protected override void OnMouseLeave(EventArgs e)
    {
        _hovering = false;
        Invalidate();
        base.OnMouseLeave(e);
    }

    protected override void OnClick(EventArgs e)
    {
        Checked = !Checked;
        base.OnClick(e);
    }
}

/// <summary>
/// Custom retro-styled button control.
/// </summary>
[SupportedOSPlatform("windows")]
public class RetroButton : Control
{
    private static readonly Color AccentCyan = Color.FromArgb(0, 255, 255);
    private static readonly Color AccentMagenta = Color.FromArgb(255, 0, 128);
    private static readonly Color TextLight = Color.FromArgb(240, 240, 255);
    private static readonly Color BorderColor = Color.FromArgb(60, 60, 80);

    private bool _hovering;
    private bool _pressing;

    public bool IsPrimary { get; set; }

    public RetroButton()
    {
        SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.DoubleBuffer, true);
        Size = new Size(100, 36);
        Cursor = Cursors.Hand;
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        var g = e.Graphics;
        g.SmoothingMode = SmoothingMode.AntiAlias;

        var accentColor = IsPrimary ? AccentCyan : AccentMagenta;

        Color bgColor;
        if (_pressing)
        {
            bgColor = Color.FromArgb(200, Color.FromArgb(60, accentColor));
        }
        else if (_hovering)
        {
            bgColor = Color.FromArgb(180, Color.FromArgb(30, accentColor));
        }
        else
        {
            bgColor = Color.FromArgb(140, Color.FromArgb(10, accentColor));
        }

        using var bgBrush = new SolidBrush(bgColor);
        g.FillRectangle(bgBrush, 0, 0, Width, Height);

        var borderWidth = _hovering ? 2 : 1;
        using var borderPen = new Pen(accentColor, borderWidth);
        g.DrawRectangle(borderPen, borderWidth / 2, borderWidth / 2,
            Width - borderWidth, Height - borderWidth);

        if (_hovering && IsPrimary)
        {
            using var glowPen = new Pen(Color.FromArgb(40, accentColor), 4);
            g.DrawRectangle(glowPen, -1, -1, Width + 1, Height + 1);
        }

        using var textFont = new Font("Consolas", 10, FontStyle.Bold);
        using var textBrush = new SolidBrush(accentColor);
        var textSize = g.MeasureString(Text, textFont);
        var textX = (Width - textSize.Width) / 2;
        var textY = (Height - textSize.Height) / 2;
        g.DrawString(Text, textFont, textBrush, textX, textY);
    }

    protected override void OnMouseEnter(EventArgs e)
    {
        _hovering = true;
        Invalidate();
        base.OnMouseEnter(e);
    }

    protected override void OnMouseLeave(EventArgs e)
    {
        _hovering = false;
        _pressing = false;
        Invalidate();
        base.OnMouseLeave(e);
    }

    protected override void OnMouseDown(MouseEventArgs e)
    {
        _pressing = true;
        Invalidate();
        base.OnMouseDown(e);
    }

    protected override void OnMouseUp(MouseEventArgs e)
    {
        _pressing = false;
        Invalidate();
        base.OnMouseUp(e);
    }
}