using System;
using System.Windows.Forms;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ControlLibrary
{
    public partial class LayerPictureBox : PictureBox
    {
        private struct Selection
        {
            public int Top;
            public int Left;
            public int Height;
            public int Width;
        }

        private bool wEdge;
        private bool eEdge;
        private bool nEdge;
        private bool sEdge;
        private bool Sizing;
        private const int EdgeSize = 6;
        private Point StartCoord;
        private Point OldCoord;
        private Point NewCoord;
        private Selection Rect;
        private bool MovePic;
        private bool MoveMain;
        private bool SizePic;


        public LayerPictureBox()
        {
            InitializeComponent();
        }

        public LayerPictureBox(IContainer container)
        {
            container.Add(this);

            InitializeComponent();
        }

        private void LayerPictureBox_MouseDown(object sender, MouseEventArgs e)
        {
            // Click on Sizable Image Region - NB. Child picturebox
            if (e.Button == MouseButtons.Left)
            {
                OldCoord = e.Location;
                StartCoord = e.Location;
                if (Sizing)
                    SizePic = true;
                else
                    MovePic = true;
            }
            if (e.Button == MouseButtons.Middle)
            {
                MoveMain = true;
                StartCoord = e.Location;
            }
        }

        private void LayerPictureBox_MouseUp(object sender, MouseEventArgs e)
        {
            // Release Click in Sizable Image Region - NB. Child picturebox
            SizePic = false;
            MovePic = false;
            MoveMain = false;
        }

        private void LayerPictureBox_MouseMove(object sender, MouseEventArgs ee)
        {
            //Mouse move inside Image Region... - NB. Child Picturebox
            if (ee.Button == MouseButtons.None)
            {
                if (ee.Location.X < EdgeSize && ee.Location.X > 0)
                    wEdge = true;
                else
                    wEdge = false;

                if (ee.Location.X > this.Size.Width - EdgeSize && ee.Location.X < this.Size.Width)
                    eEdge = true;
                else
                    eEdge = false;

                if (ee.Location.Y < EdgeSize && ee.Location.Y > 0)
                    nEdge = true;
                else
                    nEdge = false;

                if (ee.Location.Y > this.Size.Height - EdgeSize && ee.Location.Y < this.Size.Height)
                    sEdge = true;
                else
                    sEdge = false;

                Sizing = true;
            }
            else if (ee.Button == MouseButtons.Left)
            {
                if (MovePic)
                {
                    this.Top = this.Top + (ee.Location.Y - StartCoord.Y);
                    this.Left = this.Left + (ee.Location.X - StartCoord.X);
                }
                //    The code following works when used with a child Picturebox...
                //    NB. Alternate code will apply if working on a rect region selection.....
                if (SizePic)
                {
                    Rect.Top = this.Top;
                    Rect.Height = this.Height;
                    Rect.Left = this.Left;
                    Rect.Width = this.Width;
                    if (eEdge)
                        Rect.Width = ee.Location.X;
                    if (sEdge)
                        Rect.Height = ee.Location.Y;
                    if (wEdge)
                    {
                        Rect.Left = Rect.Left - (StartCoord.X - ee.Location.X);
                        Rect.Width = Rect.Width + (StartCoord.X - ee.Location.X);
                    }
                    if (nEdge)
                    {
                        Rect.Top = Rect.Top - (StartCoord.Y - ee.Location.Y);
                        Rect.Height = Rect.Height + (StartCoord.Y - ee.Location.Y);
                    }
                    if (Rect.Height < 0)
                    {
                        Rect.Top = Rect.Top + Rect.Height;
                        Rect.Height = Math.Abs(Rect.Height);
                        nEdge = !nEdge;
                        sEdge = !sEdge;
                        StartCoord.Y = 0;
                    }
                    if (Rect.Width < 0)
                    {
                        Rect.Left = Rect.Left + Rect.Width;
                        Rect.Width = Math.Abs(Rect.Width);
                        eEdge = !eEdge;
                        wEdge = !wEdge;
                        StartCoord.X = 0;
                    }
                    this.Top = Rect.Top;
                    this.Height = Rect.Height;
                    this.Left = Rect.Left;
                    this.Width = Rect.Width;
                }
            }
            if ((nEdge || sEdge) && !(wEdge || eEdge))
                this.Cursor = Cursors.SizeNS;
            else if ((wEdge || eEdge) && !(nEdge || sEdge))
                this.Cursor = Cursors.SizeWE;
            else if ((nEdge && eEdge) || (sEdge && wEdge))
                this.Cursor = Cursors.SizeNESW;
            else if ((nEdge && wEdge) || (sEdge && eEdge))
                this.Cursor = Cursors.SizeNWSE;
            else
            {
                this.Cursor = Cursors.Default;
                Sizing = false;
            }

            OldCoord = ee.Location;
            //if (MoveMain)
            //    pictureBox2_MouseMove(sender, ee);

        }

    }
}