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

using System.Runtime.InteropServices;
using ORiN2.interop.CAO;

namespace PLC
{
    public partial class Form1 : Form
    {
        private CaoEngine caoEng;
        private CaoWorkspaces caoWss;
        private CaoWorkspace caoWs;
        private CaoController caoCtrl;
        private CaoVariable caoVarD;
        private CaoVariable caoVarM;
        private CaoVariable caoVarX;
        private CaoVariable caoVarY;
        
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // Create CAO Engine
            caoEng = new CaoEngine();
            caoWss = caoEng.Workspaces;
            caoWs = caoWss.Item(0);
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            btnDisconnect_Click(sender, e);

            if (caoWs != null)
            {
                Marshal.ReleaseComObject(caoWs);
                caoWs = null;
            }

            if (caoWss != null)
            {
                Marshal.ReleaseComObject(caoWss);
                caoWss = null;
            }

            if (caoEng != null)
            {
                Marshal.ReleaseComObject(caoEng);
                caoEng = null;
            }
        }

        private void btnConnect_Click(object sender, EventArgs e)
        {
            try
            {
                // Connect Dummy.PLC Provider
                caoCtrl = caoWs.AddController("PLC", "CaoProv.Dummy.PLC", "", "");

                // Get Variable object
                caoVarD = caoCtrl.AddVariable("D16", "");
                caoVarM = caoCtrl.AddVariable("M16", "Type=Word");
                caoVarX = caoCtrl.AddVariable("X1E", "");
                caoVarY = caoCtrl.AddVariable("Y1E", "Elements=2");

                // Enable command buttons
                btnConnect.Enabled = false;
                btnDisconnect.Enabled = true;
                btnReadD.Enabled = true;
                btnReadM.Enabled = true;
                btnReadX.Enabled = true;
                btnReadY.Enabled = true;
                btnWriteD.Enabled = true;
                btnWriteM.Enabled = true;
                btnWriteX.Enabled = true;
                btnWriteY.Enabled = true;
            }
            catch (Exception ex)
            {
                btnDisconnect_Click(sender, e);
                MessageBox.Show(ex.Message);
            }
        }

        private void btnDisconnect_Click(object sender, EventArgs e)
        {
            if (caoVarY != null)
            {
                Marshal.ReleaseComObject(caoVarY);
                caoVarY = null;
            }

            if (caoVarX != null)
            {
                Marshal.ReleaseComObject(caoVarX);
                caoVarX = null;
            }

            if (caoVarM != null)
            {
                Marshal.ReleaseComObject(caoVarM);
                caoVarM = null;
            }

            if (caoVarD != null)
            {
                Marshal.ReleaseComObject(caoVarD);
                caoVarD = null;
            }

            // Disconnect Provider
            if (caoCtrl != null)
            {
                CaoControllers ctrls = caoWs.Controllers;
                ctrls.Remove(caoCtrl.Name);

                Marshal.ReleaseComObject(caoCtrl);
                caoCtrl = null;

                Marshal.ReleaseComObject(ctrls);
                ctrls = null;
            }

            // Disable command buttons
            btnConnect.Enabled = true;
            btnDisconnect.Enabled = false;
            btnReadD.Enabled = false;
            btnReadM.Enabled = false;
            btnReadX.Enabled = false;
            btnReadY.Enabled = false;
            btnWriteD.Enabled = false;
            btnWriteM.Enabled = false;
            btnWriteX.Enabled = false;
            btnWriteY.Enabled = false;
        }

        private void btnReadD_Click(object sender, EventArgs e)
        {
            try
            {
                lblDsp.Text = caoVarD.Value.ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnWriteD_Click(object sender, EventArgs e)
        {
            try
            {
                caoVarD.Value = (short)-32768;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnReadM_Click(object sender, EventArgs e)
        {
            try
            {
                lblDsp.Text = caoVarM.Value.ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnWriteM_Click(object sender, EventArgs e)
        {
            try
            {
                caoVarM.Value = (short)32767;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnReadX_Click(object sender, EventArgs e)
        {
            try
            {
                lblDsp.Text = caoVarX.Value.ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnWriteX_Click(object sender, EventArgs e)
        {
            try
            {
                caoVarX.Value = (short)1;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnReadY_Click(object sender, EventArgs e)
        {
            try
            {
                short[] iVals = (short[])caoVarY.Value;
                lblDsp.Text = string.Format("{0}, {1}", iVals[1], iVals[0]);
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void btnWriteY_Click(object sender, EventArgs e)
        {
            try
            {
                caoVarY.Value = new short[] { (short)1, (short)1 };
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
    }
}