Class to display a chat box like multiplayer

gistfile1.txt

using System;
using System.Windows.Forms;
using GTA;
using GTA.Native;
using Control = System.Windows.Forms.Control;

public delegate void UIChatMessageHandler(UIChat sender, string message);

public class UIChat : GTA.Script
{
    static int scaleform;
    static string username;
    static bool capsLock;

    public static bool Active { get; private set; }

    private static DateTime displayTimer;

    public static event UIChatMessageHandler MessageSent;

    private string textBuffer = null;

    public UIChat()
    {
        Tick += OnTick;
        KeyDown += KeyPressed;
        KeyUp += KeyReleased;
        scaleform = Function.Call<int>(Hash.REQUEST_SCALEFORM_MOVIE, "multiplayer_chat");
        username = Game.Player.Name;
        Active = false;
    }

    private void KeyReleased(object sender, KeyEventArgs e)
    {
        if (Active && e.KeyCode == Keys.CapsLock)
            capsLock = Control.IsKeyLocked(Keys.CapsLock);
    }

    private void KeyPressed(object sender, KeyEventArgs e)
    {
        if (!Active)
            return;

        char keyChar = KeyHelper.GetCharFromKey(e.KeyCode, (e.Modifiers & Keys.Shift) != 0);

        if (char.IsLetterOrDigit(keyChar))
        {
            if (capsLock)
                keyChar = char.ToUpper(keyChar);
        }

        else
        {
            switch (e.KeyCode)
            {
                case Keys.Back:
                {
                    if (textBuffer.Length < 1)
                    {
                        SetTypingDone();
                        SetVisibleState(VisibleState.Default);
                        ResetDisplayTimer(5000);
                    }
                    else
                    {
                        SetVisibleState(VisibleState.Typing);
                        textBuffer = textBuffer.Substring(0, textBuffer.Length - 1);
                        AddTypingText(textBuffer);
                    }
                    return;
                }
                case Keys.Enter:
                    OnMessageSent(textBuffer);
                    SetTypingDone(true);
                    SetVisibleState(VisibleState.Default);
                    ResetDisplayTimer(5000);
                    return;

                case Keys.Escape:
                    SetTypingDone();
                    SetVisibleState(VisibleState.Default);
                    ResetDisplayTimer(5000);
                    return;
            }
        }

        AddTypingText(keyChar);
    }

    private static void OnTick(object sender, EventArgs e)
    {
        if (displayTimer.Ticks > 0 && DateTime.Now > displayTimer)
        {
            SetVisibleState(VisibleState.Hidden);
            displayTimer = new DateTime();
        }

        if (Active)
        {
            Function.Call(Hash.DISABLE_ALL_CONTROL_ACTIONS, 0);

            if (Function.Call<bool>(Hash.IS_DISABLED_CONTROL_JUST_PRESSED, 0, (int) GTA.Control.CursorScrollUp))
            {
                Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "PAGE_UP");
                Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);
            }

            else if (Function.Call<bool>(Hash.IS_DISABLED_CONTROL_JUST_PRESSED, 0, (int) GTA.Control.CursorScrollDown))
            {
                Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "PAGE_DOWN");
                Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);
            }
        }

        Function.Call((Hash) 0x0DF606929C105BE1, scaleform, 255, 255, 255, 100, 0);
    }

    protected void AddTypingText(string text)
    {
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "ADD_TEXT");
        Function.Call(Hash._BEGIN_TEXT_COMPONENT, "STRING");
        Function.Call(Hash._ADD_TEXT_COMPONENT_STRING, text);
        Function.Call(Hash._END_TEXT_COMPONENT);
        Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);
    }

    protected void AddTypingText(char text)
    {
        AddTypingText(Convert.ToString(text));
    }

    protected void SetTypingDone(bool addMessage = false)
    {
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "SET_TYPING_DONE");
        Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);

        if (addMessage)
        {
            AddFeedMessage(username, textBuffer);
        }

        textBuffer = string.Empty;
    }

    public static void SetVisibleState(VisibleState state, TypeMode mode = TypeMode.None)
    {
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "SET_FOCUS");
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION_PARAMETER_INT, (int) state);
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION_PARAMETER_INT, (int) mode);
        Function.Call(Hash._BEGIN_TEXT_COMPONENT, "STRING");
        Function.Call(Hash._ADD_TEXT_COMPONENT_STRING, username);
        Function.Call(Hash._END_TEXT_COMPONENT);
        Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);
        Active = state == VisibleState.Typing;
        if (Active) displayTimer = new DateTime();
    }

    public static void AddFeedMessage(string name, string message)
    {
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION, scaleform, "ADD_MESSAGE");
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION_PARAMETER_STRING, name.Length < 0 ? "undefined" : name);
        Function.Call(Hash._PUSH_SCALEFORM_MOVIE_FUNCTION_PARAMETER_STRING, message);
        Function.Call(Hash._POP_SCALEFORM_MOVIE_FUNCTION_VOID);
        if (!Active) ResetDisplayTimer(5000);
    }

    private static void ResetDisplayTimer(int interval)
    {
        displayTimer = DateTime.Now + TimeSpan.FromMilliseconds(interval);
    }

    protected virtual void OnMessageSent(string msg)
    {
        MessageSent?.Invoke(this, msg);
    }

    public static void SetLocalUsername(string Username)
    {
        username = Username;
    }

    public enum VisibleState
    {
        Hidden,
        Default,
        Typing
    }

    public enum TypeMode
    {
        None,
        Team,
        All,
        Clan
    }
}