using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;

internal static class NativeMethods
{
    internal const int WM_HOTKEY = 0x0312;
    internal const int HOTKEY_ID = 1;
    internal const uint KEYEVENTF_KEYUP = 0x0002;
    internal const byte VK_CONTROL = 0x11;
    internal const uint MOUSEEVENTF_LEFTDOWN = 0x0002;
    internal const uint MOUSEEVENTF_LEFTUP = 0x0004;

    [DllImport("user32.dll")]
    internal static extern bool RegisterHotKey(IntPtr hWnd, int id, uint modifiers, uint key);

    [DllImport("user32.dll")]
    internal static extern bool UnregisterHotKey(IntPtr hWnd, int id);

    [DllImport("user32.dll")]
    internal static extern void keybd_event(byte virtualKey, byte scanCode, uint flags, UIntPtr extraInfo);

    [DllImport("user32.dll")]
    internal static extern void mouse_event(uint flags, uint dx, uint dy, uint data, UIntPtr extraInfo);
}

internal sealed class HelperForm : Form
{
    private const int DwellMilliseconds = 100;
    private const int MovementThreshold = 6;

    private readonly Timer timer;
    private readonly Button toggleButton;
    private readonly Label statusLabel;
    private Point anchor;
    private DateTime stableSince;
    private DateTime cooldownUntil;
    private bool enabled;
    private bool clickLocked;

    internal HelperForm()
    {
        Text = "PoE2 Accessibility Click Helper";
        ClientSize = new Size(500, 250);
        MinimumSize = new Size(500, 250);
        StartPosition = FormStartPosition.CenterScreen;
        TopMost = true;
        BackColor = Color.FromArgb(15, 15, 24);
        ForeColor = Color.White;
        Font = new Font("Segoe UI", 12F);

        var title = new Label {
            Text = "Помощник Ctrl + Left Click",
            Font = new Font("Segoe UI", 18F, FontStyle.Bold),
            ForeColor = Color.FromArgb(220, 190, 100),
            AutoSize = false,
            TextAlign = ContentAlignment.MiddleCenter,
            Bounds = new Rectangle(15, 15, 470, 45)
        };

        toggleButton = new Button {
            Text = "ВКЛЮЧИТЬ (F8)",
            Font = new Font("Segoe UI", 18F, FontStyle.Bold),
            BackColor = Color.FromArgb(40, 110, 65),
            ForeColor = Color.White,
            FlatStyle = FlatStyle.Flat,
            Bounds = new Rectangle(60, 70, 380, 70)
        };
        toggleButton.Click += delegate { Toggle(); };

        statusLabel = new Label {
            Text = "ВЫКЛЮЧЕНО — кликов не будет",
            Font = new Font("Segoe UI", 12F, FontStyle.Bold),
            ForeColor = Color.FromArgb(255, 100, 100),
            AutoSize = false,
            TextAlign = ContentAlignment.MiddleCenter,
            Bounds = new Rectangle(20, 148, 460, 35)
        };

        var help = new Label {
            Text = "Наведи курсор и удерживай 0,1с. Один Ctrl+Click, затем сдвинь курсор.\nF8 — мгновенно включить или выключить.",
            ForeColor = Color.FromArgb(190, 190, 200),
            AutoSize = false,
            TextAlign = ContentAlignment.MiddleCenter,
            Bounds = new Rectangle(20, 185, 460, 50)
        };

        Controls.Add(title);
        Controls.Add(toggleButton);
        Controls.Add(statusLabel);
        Controls.Add(help);

        timer = new Timer { Interval = 20 };
        timer.Tick += OnTimerTick;
        timer.Start();

        anchor = Cursor.Position;
        stableSince = DateTime.UtcNow;
    }

    protected override void OnHandleCreated(EventArgs e)
    {
        base.OnHandleCreated(e);
        NativeMethods.RegisterHotKey(Handle, NativeMethods.HOTKEY_ID, 0, (uint)Keys.F8);
    }

    protected override void OnHandleDestroyed(EventArgs e)
    {
        NativeMethods.UnregisterHotKey(Handle, NativeMethods.HOTKEY_ID);
        base.OnHandleDestroyed(e);
    }

    protected override void WndProc(ref Message message)
    {
        if (message.Msg == NativeMethods.WM_HOTKEY && message.WParam.ToInt32() == NativeMethods.HOTKEY_ID) {
            Toggle();
            return;
        }
        base.WndProc(ref message);
    }

    private void Toggle()
    {
        enabled = !enabled;
        clickLocked = false;
        cooldownUntil = DateTime.MinValue;
        anchor = Cursor.Position;
        stableSince = DateTime.UtcNow;
        toggleButton.Text = enabled ? "ВЫКЛЮЧИТЬ (F8)" : "ВКЛЮЧИТЬ (F8)";
        toggleButton.BackColor = enabled ? Color.FromArgb(135, 45, 45) : Color.FromArgb(40, 110, 65);
        statusLabel.Text = enabled ? "ВКЛЮЧЕНО — удержание 0,1с" : "ВЫКЛЮЧЕНО — кликов не будет";
        statusLabel.ForeColor = enabled ? Color.FromArgb(90, 230, 125) : Color.FromArgb(255, 100, 100);
    }

    private void OnTimerTick(object sender, EventArgs e)
    {
        if (!enabled) return;

        DateTime now = DateTime.UtcNow;
        Point current = Cursor.Position;
        int dx = current.X - anchor.X;
        int dy = current.Y - anchor.Y;
        bool moved = (dx * dx + dy * dy) >= MovementThreshold * MovementThreshold;

        if (moved) {
            anchor = current;
            stableSince = now;
        }

        if (clickLocked) {
            if (now < cooldownUntil) {
                double remaining = Math.Ceiling((cooldownUntil - now).TotalMilliseconds / 100.0) / 10.0;
                statusLabel.Text = "Пауза " + remaining.ToString("0.0") + "с";
                return;
            }
            clickLocked = false;
            stableSince = now;
            statusLabel.Text = "ВКЛЮЧЕНО — готов к следующему клику";
        }

        if (Bounds.Contains(current)) return;
        if ((now - stableSince).TotalMilliseconds < DwellMilliseconds) return;

        clickLocked = true;
        cooldownUntil = now.AddSeconds(3);
        PerformControlClick();
        statusLabel.Text = "CTRL + CLICK выполнен — пауза 3,0с";
    }

    private static void PerformControlClick()
    {
        NativeMethods.keybd_event(NativeMethods.VK_CONTROL, 0, 0, UIntPtr.Zero);
        NativeMethods.mouse_event(NativeMethods.MOUSEEVENTF_LEFTDOWN, 0, 0, 0, UIntPtr.Zero);
        NativeMethods.mouse_event(NativeMethods.MOUSEEVENTF_LEFTUP, 0, 0, 0, UIntPtr.Zero);
        NativeMethods.keybd_event(NativeMethods.VK_CONTROL, 0, NativeMethods.KEYEVENTF_KEYUP, UIntPtr.Zero);
    }
}

internal static class Program
{
    [STAThread]
    private static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new HelperForm());
    }
}