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

namespace _314_XML_Example
{
    public partial class FormMain : Form
    {
        private DataSet ds;

        //--------------------------------------------------------------------------

        public FormMain()
        {
            InitializeComponent();
        }

        //--------------------------------------------------------------------------

        private void numericUpDown1_ValueChanged(object sender, EventArgs e)
        {
            CalculateMileageExpense();
        }

        //--------------------------------------------------------------------------

        private void textBoxMilesDriven_TextChanged(object sender, EventArgs e)
        {
            CalculateMileageExpense();
        }

        //--------------------------------------------------------------------------

        private void CalculateMileageExpense()
        {
            try
            {
                labelMileageExpense.Text = (numericUpDownMileageRate.Value * 
                    Decimal.Parse(textBoxMilesDriven.Text)).ToString();
            }
            catch
            {
                labelMileageExpense.Text = "$0.00";
            }
        }

        //--------------------------------------------------------------------------

        private void textBoxBreakfast_TextChanged(object sender, EventArgs e)
        {
            CalculateMealsExpense();
        }

        //--------------------------------------------------------------------------

        private void CalculateMealsExpense()
        {
            double mb, ml, md;

            try
            {
                mb = Math.Max(0.0, Math.Min(5.0, Double.Parse(textBoxBreakfast.Text)));
            }
            catch
            {
                mb = 0.0;
            }

            try
            {
                ml = Math.Max(0.0, Math.Min(10.0, Double.Parse(textBoxLunch.Text)));
            }
            catch
            {
                ml = 0.0;
            }

            try
            {
                md = Math.Max(0.0, Math.Min(15.0, Double.Parse(textBoxDinner.Text)));
            }
            catch
            {
                md = 0.0;
            }

            labelMealsExpense.Text = String.Format("{0:c}", (mb + ml + md).ToString());
        }

        //--------------------------------------------------------------------------

        private void textBoxMoviesPhone_TextChanged(object sender, EventArgs e)
        {
            CalculateLodgingExpense();
        }

        //--------------------------------------------------------------------------

        private void CalculateLodgingExpense()
        {
            double rr, rmp;

            try
            {
                rr = Double.Parse(textBoxRoomRate.Text);
            }
            catch
            {
                rr = 0.0;
            }

            try
            {
                rmp = Double.Parse(textBoxMoviesPhone.Text);
            }
            catch
            {
                rmp = 0.0;
            }

            labelLodgingExpense.Text = String.Format("{0:c}", (rr + rmp).ToString());
        }

        //--------------------------------------------------------------------------

        private void RecalculateDailyTotal(object sender, EventArgs e)
        {
            double le, fe, me;

            try
            {
                le = Double.Parse(labelLodgingExpense.Text);
            }
            catch
            {
                le = 0.0;
            }

            try
            {
                fe = Double.Parse(labelMealsExpense.Text);
            }
            catch
            {
                fe = 0.0;
            }

            try
            {
                me = Double.Parse(labelMileageExpense.Text);
            }
            catch
            {
                me = 0.0;
            }
            
            labelTotal.Text = String.Format("{0:c}", (le + fe + me).ToString());
        }

        //--------------------------------------------------------------------------

        private void DisplayDS()
        {
            Console.WriteLine("********************** STATE OF DATASET ************************");
            foreach (DataTable dt in ds.Tables)
            {
                Console.WriteLine();
                Console.WriteLine("Table: " + dt.TableName);

                Console.WriteLine("------------------------------------------------------");
                foreach (DataColumn dc in dt.Columns)
                    Console.Write("{0, -15}", dc.ColumnName);
                Console.WriteLine();
                Console.WriteLine("------------------------------------------------------");

                foreach (DataRow dr in dt.Rows)
                {
//                    Console.WriteLine("  Row: " + dr.ToString());
                    foreach (Object o in dr.ItemArray)
                    {
                        Console.Write("{0, -15}", o.ToString());
                    }
                    Console.WriteLine();
                }
            }
            Console.WriteLine("***************************************************************");
        }

        //--------------------------------------------------------------------------

        private string GetNewID()
        {
            int new_id = 0;
            int id;

            foreach (DataRow dr in ds.Tables["DAY"].Rows)
            {
                id = Int32.Parse(dr["DAY_id"].ToString());
                if (id > new_id)
                    new_id = id;
            }

            new_id++;

            return new_id.ToString();
        }

        //--------------------------------------------------------------------------

        private void InsertNewRow(string ssd)
        {
            DataRow dr;
            string id = GetNewID();

            dr = ds.Tables["DAY"].NewRow();
            dr["DAY_id"] = id;
            dr["date"] = ssd;
            ds.Tables["DAY"].Rows.Add(dr);

            dr = ds.Tables["meals"].NewRow();
            dr["breakfast"] = textBoxBreakfast.Text;
            dr["lunch"] = textBoxLunch.Text;
            dr["dinner"] = textBoxDinner.Text;
            dr["DAY_id"] = id;
            ds.Tables["meals"].Rows.Add(dr);

            dr = ds.Tables["travel"].NewRow();
            dr["rate"] = numericUpDownMileageRate.Value.ToString();
            dr["miles"] = textBoxMilesDriven.Text;
            dr["DAY_id"] = id;
            ds.Tables["travel"].Rows.Add(dr);

            dr = ds.Tables["lodging"].NewRow();
            dr["rate"] = textBoxRoomRate.Text;
            dr["phone_movies"] = textBoxMoviesPhone.Text;
            dr["DAY_id"] = id;
            ds.Tables["lodging"].Rows.Add(dr);
        }

        //--------------------------------------------------------------------------

        private void UpdateRow(string d_id)
        {
            DataRow[] drs;

            drs = ds.Tables["meals"].Select("DAY_id = '" + d_id + "'");
            drs[0]["breakfast"] = textBoxBreakfast.Text;
            drs[0]["lunch"] = textBoxLunch.Text;
            drs[0]["dinner"] = textBoxDinner.Text;

            drs = ds.Tables["travel"].Select("DAY_id = '" + d_id + "'");
            drs[0]["rate"] = numericUpDownMileageRate.Value.ToString();
            drs[0]["miles"] = textBoxMilesDriven.Text;

            drs = ds.Tables["lodging"].Select("DAY_id = '" + d_id + "'");
            drs[0]["rate"] = textBoxRoomRate.Text;
            drs[0]["phone_movies"] = textBoxMoviesPhone.Text;
        }

        //--------------------------------------------------------------------------

        private void buttonSave_Click(object sender, EventArgs e)
        {
            DateTime selected_date = dateTimePicker1.Value;
            string ssd = selected_date.ToShortDateString(); 
            DataRow[] drs = ds.Tables["DAY"].Select("date = '" + ssd + "'");

            if (drs.Length == 0)
                InsertNewRow(ssd);
            else
            {
                string d_id = drs[0][0].ToString(); 
                UpdateRow(d_id);
            }

            DisplayDS();

            ds.WriteXml("sample.xml");
        }

        //--------------------------------------------------------------------------

        private void FormMain_Load(object sender, EventArgs e)
        {
            ds = new DataSet();
            ds.ReadXml("sample.xml");
        }

        //--------------------------------------------------------------------------

        private void ClearData()
        {
            textBoxBreakfast.Text = "";
            textBoxLunch.Text = "";
            textBoxDinner.Text = "";
            textBoxRoomRate.Text = "";
            textBoxMoviesPhone.Text = "";
            textBoxMilesDriven.Text = "";
            numericUpDownMileageRate.Value = 0.42M;
        }

        //--------------------------------------------------------------------------

        private void dateTimePicker1_ValueChanged(object sender, EventArgs e)
        {
            DateTime selected_date = dateTimePicker1.Value;
            string ssd = selected_date.ToShortDateString();

            DataRow[] drs = ds.Tables["DAY"].Select("date = '" + ssd + "'");

            if (drs.Length == 0)
            {
                ClearData();
                return;
            }

            string d_id = drs[0][0].ToString();

            drs = ds.Tables["meals"].Select("DAY_id = '" + d_id + "'");

            if (drs.Length == 0)
            {
                ClearData();
                return;
            }

            textBoxBreakfast.Text = drs[0]["breakfast"].ToString();
            textBoxLunch.Text = drs[0]["lunch"].ToString();
            textBoxDinner.Text = drs[0]["dinner"].ToString();

            drs = ds.Tables["lodging"].Select("DAY_id = '" + d_id + "'");

            if (drs.Length == 0)
            {
                ClearData();
                return;
            }

            textBoxRoomRate.Text = drs[0]["rate"].ToString();
            textBoxMoviesPhone.Text = drs[0]["phone_movies"].ToString();

            drs = ds.Tables["travel"].Select("DAY_id = '" + d_id + "'");

            if (drs.Length == 0)
            {
                ClearData();
                return;
            }

            textBoxMilesDriven.Text = drs[0]["miles"].ToString();
            numericUpDownMileageRate.Value = Decimal.Parse(drs[0]["rate"].ToString());
        }

        //--------------------------------------------------------------------------

    }
}