using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Text;
using System.Windows.Forms;

namespace AMT_SW_GUI
{
    public delegate void OutOfRangeeventhandler();
    public delegate void TextChangedEventHandler(object sender, EventArgs e);

    public partial class AMT_IPAddress : UserControl
    {
        private Control activeControl;

        public event OutOfRangeeventhandler OutOfRangeError;
        public event TextChangedEventHandler TextChanged;
        public AMT_IPAddress()
        {
            InitializeComponent();
        }

        public Control ActiveControl
        {
            get
            {
                return activeControl;
            }

            set
            {
                if (this.Controls.Contains(value))
                {
                    activeControl = value;
                }
            }
        }

        public bool ActivateControl(Control active)
        {
            if (this.Controls.Contains(active))
            {
                active.Select();
                this.activeControl = active;
                return true;
            }
            return false;
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            e.Graphics.DrawRectangle(new Pen(Color.FromArgb(158, 191, 217), 1), new Rectangle(0, 0, this.Width - 1, this.Height - 1));
        }

        public override string Text
        {
            get
            {
                return Box1.Text + "." + Box2.Text + "." + Box3.Text + "." + Box4.Text;
            }
            set
            {
                if (value != "" && value != null)
                {
                    string[] pieces = new string[4];
                    pieces = value.ToString().Split(".".ToCharArray(), 4);
                    Box1.Text = pieces[0];
                    Box2.Text = pieces[1];
                    Box3.Text = pieces[2];
                    Box4.Text = pieces[3];
                }
                else
                {
                    Box1.Text = "";
                    Box2.Text = "";
                    Box3.Text = "";
                    Box4.Text = "";
                }
            }
        }

        public TextBox Octet1
        {
            get { return Box1; }
        }

        public TextBox Octet2
        {
            get { return Box2; }
        }

        public TextBox Octet3
        {
            get { return Box3; }
        }

        public TextBox Octet4
        {
            get { return Box4; }
        }

        public bool IsValid()
        {
            try
            {
                int checkval = int.Parse(Box1.Text);
                if (checkval < 0 || checkval > 223)
                    return false;
                checkval = int.Parse(Box2.Text);
                if (checkval < 0 || checkval > 255)
                    return false;
                checkval = int.Parse(Box3.Text);
                if (checkval < 0 || checkval > 255)
                    return false;
                checkval = int.Parse(Box4.Text);
                if (checkval < 0 || checkval > 255)
                    return false;
                else
                    return true;
            }
            catch
            {
                return false;
            }
        }

        private bool IsValid(TextBox sender, string inString)
        {
            try
            {
                int theValue = int.Parse(inString);
                if (sender == Box1)
                {
                    if (theValue >= 1 && theValue <= 223)
                    {
                        return true;
                    }
                }
                else if (theValue >= 0 && theValue <= 255)
                    return true;
                else
                {
                    if (OutOfRangeError != null)
                    {
                        OutOfRangeError();
                    }
                }
                return false;
            }
            catch
            {
                return false;
            }
        }

        private bool DiscoverPrefixZero(TextBox sender, System.Windows.Forms.KeyPressEventArgs e)
        {

            if (((((TextBox)(sender)).Text == "0") && (((TextBox)(sender)).SelectionStart == 1) && (Char.IsDigit(e.KeyChar))) ||
                    ((e.KeyChar.ToString() == "0") && (((TextBox)(sender)).SelectionStart == 0) && (((TextBox)(sender)).Text.Length > 0)))
            {
                if (((TextBox)(sender)).SelectedText.Length < ((TextBox)(sender)).Text.Length)
                {
                    return true;
                }
            }
            return false;

        }

        private void Box1_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            bool prefixZero = DiscoverPrefixZero((TextBox)sender, e);
            if (prefixZero)
            {
                e.Handled = true;
                return;
            }

            if (e.KeyChar.ToString() == "." || Char.IsDigit(e.KeyChar) || e.KeyChar == 8)
            {
                if (e.KeyChar.ToString() == ".")
                {
                    if (Box1.Text != "" && Box1.Text.Length != Box1.SelectionLength)
                    {
                        if (IsValid(Box1, Box1.Text))
                            Box2.Focus();
                        else
                            Box1.SelectAll();
                    }
                    e.Handled = true;
                }

                else if (Box1.SelectionLength != Box1.Text.Length)
                {
                    if (Box1.Text.Length == 2)
                    {
                        if (e.KeyChar == 8)
                            Box1.Text.Remove(Box1.Text.Length - 1, 1);
                        else if (!IsValid((TextBox)sender, InsertKeyChar((TextBox)sender, e)))
                        {

                            Box2.SelectAll();
                            e.Handled = true;
                        }
                        else
                        {
                            Box2.Focus();
                        }
                    }
                }
            }

            else
                e.Handled = true;
        }

        private void Box2_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            bool prefixZero = DiscoverPrefixZero((TextBox)sender, e);
            if (prefixZero)
            {
                e.Handled = true;
                return;
            }

            if (e.KeyChar.ToString() == "." || Char.IsDigit(e.KeyChar) || e.KeyChar == 8)
            {
                if (e.KeyChar.ToString() == ".")
                {
                    if (Box2.Text != "" && Box2.Text.Length != Box2.SelectionLength)
                    {
                        if (IsValid(Box2, Box2.Text))
                            Box3.Focus();
                        else
                            Box2.SelectAll();
                    }
                    e.Handled = true;
                }
                else if (e.KeyChar == 8 && Box2.SelectionStart == 0)
                {
                    if(Box1.Text!="")
                    {
                        Box1.Text = Box1.Text.Remove(Box1.Text.Length - 1, 1);
                    }
                    Box1.Focus();
                    Box1.SelectionStart = Box1.Text.Length;
                    Box1.SelectionLength = 0;
                    return;
                }

                else if (Box2.SelectionLength != Box2.Text.Length)
                {
                    if (Box2.Text.Length == 2)
                    {
                        if (e.KeyChar == 8)
                        {
                            Box2.Text.Remove(Box2.Text.Length - 1, 1);
                        }
                        else if (!IsValid((TextBox)sender, InsertKeyChar((TextBox)sender, e)))
                        {

                            Box2.SelectAll();
                            e.Handled = true;
                        }
                        else
                        {
                            Box3.Focus();
                        }

                    }

                }
            }
            else if (Box2.Text.Length == 0 && e.KeyChar == 8)
            {
                Box1.Focus();
                Box1.SelectionStart = Box1.Text.Length;
            }

            else
                e.Handled = true;

        }

        private void Box3_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            bool prefixZero = DiscoverPrefixZero((TextBox)sender, e);
            if (prefixZero)
            {
                e.Handled = true;
                return;
            }

            if (e.KeyChar.ToString() == "." || Char.IsDigit(e.KeyChar) || e.KeyChar == 8)
            {
                if (e.KeyChar.ToString() == ".")
                {
                    if (Box3.Text != "" && Box3.SelectionLength != Box3.Text.Length)
                    {
                        if (IsValid(Box3, Box3.Text))
                            Box4.Focus();
                        else
                            Box3.SelectAll();
                    }
                    e.Handled = true;
                }
                else if (e.KeyChar == 8 && Box3.SelectionStart == 0)
                {
                    if (Box2.Text != "")
                    {
                        Box2.Text = Box2.Text.Remove(Box2.Text.Length - 1, 1);
                    }
                    Box2.Focus();
                    Box2.SelectionStart = Box1.Text.Length;
                    Box2.SelectionLength = 0;
                    return;
                }
                else if (Box3.SelectionLength != Box3.Text.Length)
                {
                    if (Box3.Text.Length == 2)
                    {
                        if (e.KeyChar == 8)
                        {
                            Box3.Text.Remove(Box3.Text.Length - 1, 1);
                        }
                        else if (!IsValid((TextBox)sender, InsertKeyChar((TextBox)sender, e)))
                        {
                            Box3.SelectAll();
                            e.Handled = true;
                        }
                        else
                        {
                            Box4.Focus();
                        }

                    }

                }
            }
            else if (Box3.Text.Length == 0 && e.KeyChar == 8)
            {
                Box2.Focus();
                Box2.SelectionStart = Box2.Text.Length;
            }

            else
                e.Handled = true;
        }

        private void Box4_KeyPress(object sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            bool prefixZero = DiscoverPrefixZero((TextBox)sender, e);
            if (prefixZero)
            {
                e.Handled = true;
                return;
            }
            
            if (Char.IsDigit(e.KeyChar) || e.KeyChar == 8)
            {
                if (e.KeyChar == 8 && Box4.SelectionStart == 0)
                {
                    if(Box3.Text!="")
                    {
                        Box3.Text = Box3.Text.Remove(Box3.Text.Length - 1, 1);
                    }
                    Box3.Focus();
                    Box3.SelectionStart = Box1.Text.Length;
                    Box3.SelectionLength = 0;
                    return;
                }
                if (Box4.SelectionLength != Box4.Text.Length)
                {
                    if (Box4.Text.Length == 2)
                    {
                        if (e.KeyChar == 8)
                        {
                            Box4.Text.Remove(Box4.Text.Length - 1, 1);
                        }
                        else if (!IsValid((TextBox)sender, InsertKeyChar((TextBox)sender, e)))
                        {
                            Box4.SelectAll();
                            e.Handled = true;
                        }
                    }
                }
                else if (Box4.Text.Length == 0 && e.KeyChar == 8)
                {
                    Box3.Focus();
                    Box3.SelectionStart = Box3.Text.Length;
                }
            }
            else
                e.Handled = true;
        }

        void Box_TextChanged(object sender, System.EventArgs e)
        {
            if (TextChanged != null)
                TextChanged(this, new EventArgs());
        }

        private string InsertKeyChar(TextBox sender, System.Windows.Forms.KeyPressEventArgs e)
        {
            string prefix = "";
            string postfix = "";

            try
            {
                if (((TextBox)(sender)).SelectionStart != 0)
                {
                    prefix = ((TextBox)(sender)).Text.Substring(0, ((TextBox)(sender)).SelectionStart);
                }

                if (((TextBox)(sender)).SelectionStart != Box4.Text.Length)
                {
                    postfix = ((TextBox)(sender)).Text.Substring(((TextBox)(sender)).SelectionStart, ((TextBox)(sender)).Text.Length - Box4.SelectionStart);
                }
            }
            catch (Exception)
            {
            }

            string str = prefix + e.KeyChar.ToString() + postfix;

            return str;
        }

        private void Box_Enter(object sender, System.EventArgs e)
        {
            TextBox tb = (TextBox)sender;
            tb.SelectAll();
        }

        private void label_EnabledChanged(object sender, System.EventArgs e)
        {
            Label lbl = (Label)sender;
            if (lbl.Enabled)
                lbl.BackColor = SystemColors.Window;
            else
                lbl.BackColor = SystemColors.Control;
            Invalidate();
        }

        private void AMT_IPAddress_EnabledChanged(object sender, System.EventArgs e)
        {
            if (sender is AMT_IPAddress)
            {
                AMT_IPAddress pan = (AMT_IPAddress)sender;
                if (pan.Enabled)
                    pan.BackColor = SystemColors.Window;
                else
                    pan.BackColor = SystemColors.Control;
            }
        }

        protected override bool ProcessKeyPreview(ref System.Windows.Forms.Message m)
        {
            switch (m.WParam.ToInt32())
            {
                case 37: // <--- left arrow.
                    SetFocus(EARROWS.LEFT);
                    break;
                case 38: // <--- up arrow.
                    SetFocus(EARROWS.LEFT);
                    break;
                case 39: // <--- right arrow.
                    SetFocus(EARROWS.RIGHT);
                    break;
                case 40: // <--- down arrow.
                    SetFocus(EARROWS.RIGHT);
                    break;
            }
            return false;
        }

        protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
        {
            if ((keyData == Keys.Up || keyData == Keys.Left || keyData == Keys.Right || keyData == Keys.Down))
            {
                return true;
            }
            else
            {
                return base.ProcessCmdKey(ref msg, keyData);
            }
        }

        private void SetFocus(EARROWS direction)
        {
            TextBox box;
            box = FocusedBox();
            if (box == null)
                return;

            switch (direction)
            {
                case EARROWS.RIGHT:
                    {
                        if (box.Text.Length > box.SelectionStart)
                        {
                            box.SelectionStart += 1;
                        }
                        else
                        {
                            if (box == Box1)
                            {
                                Box2.Focus();
                                Box2.SelectionLength = 0;
                            }
                            else if (box == Box2)
                            {
                                Box3.Focus();
                                Box3.SelectionLength = 0;
                            }
                            else if (box == Box3)
                            {
                                Box4.Focus();
                                Box4.SelectionLength = 0;
                            }
                        }
                    }
                    break;


                case EARROWS.LEFT:
                    {
                        if (box.SelectionStart > 0)
                        {
                            box.SelectionStart -= 1;
                        }
                        else
                        {
                            if (box == Box2)
                            {
                                Box1.Focus();
                                Box1.SelectionStart = Box1.Text.Length;
                            }
                            else if (box == Box3)
                            {
                                Box2.Focus();
                                Box2.SelectionStart = Box1.Text.Length;
                            }
                            else if (box == Box4)
                            {
                                Box3.Focus();
                                Box3.SelectionStart = Box1.Text.Length;
                            }


                        }
                    }
                    break;
            }
        }

        private TextBox FocusedBox()
        {
            if (this.Box1.Focused)
                return (Box1);
            if (this.Box2.Focused)
                return (Box2);
            if (this.Box3.Focused)
                return (Box3);
            if (this.Box4.Focused)
                return (Box4);
            return null;
        }

        public enum EARROWS
        {
            LEFT = 0,
            RIGHT = 1
        }

    }
}