InformationSystemSales.cs

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

namespace VPEx2
{
    public partial class InformationSystemSales : Form
    {
        public InformationSystemSales()
        {
            InitializeComponent();
            listviewSales.View = View.Details;
            listviewSales.Columns.Add("Date", 100, HorizontalAlignment.Left);
            listviewSales.Columns.Add("Article", 80, HorizontalAlignment.Left);
            listviewSales.Columns.Add("Unit Price", 60, HorizontalAlignment.Left);
            listviewSales.Columns.Add("Qty", 50, HorizontalAlignment.Left);
            listviewSales.Columns.Add("Discount", 66, HorizontalAlignment.Left);
            listviewSales.Columns.Add("Total Amount", 100, HorizontalAlignment.Left);
        }

        int numOfSales = 0;
        decimal grandDiscountValue = 0.0m;
        decimal grandTotalValue = 0.0m;
        ToolTip toolTip = new ToolTip();
        MessageBoxButtons button = MessageBoxButtons.OK;
        DialogResult result;

        private void newSaleBtn_Click(object sender, EventArgs e)
        {
            MessageBoxButtons button = MessageBoxButtons.OK;
            DialogResult result;
            string newSaleMessage = "Inputting data for a sale.";
            string newSaleCaption = "New Sale";
            result = MessageBox.Show(newSaleMessage, newSaleCaption, button);
            article.Text = "";
            unitPrice.Clear();
            quantity.Clear();
            discount.Clear();
            totalAmount.Clear();
            totalBtn.Enabled = true;
            newSaleBtn.Enabled = false;
            discountLabel.ForeColor = Color.Black;
        }
        private void totalBtn_Click(object sender, EventArgs e)
        {
            decimal discountValue = 0.0m;
            decimal totalAmountValue = 0.0m;
            string fieldIsIncorrect = "Some of the input data is incorrect. Please make sure you enter a valid data.";

            double n;
            bool isNumeric = double.TryParse(unitPrice.Text, out n) &&
                double.TryParse(quantity.Text, out n);

            if (article.SelectedIndex == -1 || !isNumeric ||
                unitPrice.Text.Trim().Length == 0 || quantity.Text.Trim().Length == 0 ||
                selectedCurrency.SelectedIndex == -1 ||
                int.Parse(unitPrice.Text) <= 0 || int.Parse(quantity.Text) <= 0)
            {
                MessageBox.Show(fieldIsIncorrect, "Error", button);
            }
            else
            {
                string totalMessage = "Calculating discount and total amount of a current entered sale.";
                string totalCaption = "Total";
                result = MessageBox.Show(totalMessage, totalCaption, button);

                decimal unitPriceValue = decimal.Parse(unitPrice.Text);
                int quantityValue = int.Parse(quantity.Text);
                totalAmountValue = unitPriceValue * quantityValue;
                double discountPercent = 0.1;

                if (totalAmountValue >= 100)
                {
                    discountValue = (decimal)discountPercent * totalAmountValue;
                    totalAmountValue = totalAmountValue - discountValue;
                }
                else
                {
                    discountValue = 0;
                }
                if (discountValue > 0)
                {
                    grandDiscountValue += discountValue;
                    discountLabel.ForeColor = Color.Red;
                }
                else
                {
                    discountLabel.ForeColor = Color.Black;
                }

                numOfSales++;
                grandTotalValue += totalAmountValue;

                totalAmount.Text = string.Format("{0:0.00}", totalAmountValue);
                discount.Text = string.Format("{0:0.00}", discountValue);

                newSaleBtn.Enabled = true;
                totalBtn.Enabled = false;
                selectDate.Enabled = false;
            }
            string[] currentRow = { article.Text, unitPrice.Text, quantity.Text,
                               discount.Text, totalAmount.Text };
            listviewSales.Items.Add(Convert.ToString(selectDate.Text)).SubItems.AddRange(currentRow);
        }

        public Boolean IsNumber(String value)
        {
            Boolean isNum = true;
            foreach (Char c in value.ToCharArray())
            {
                isNum = isNum && Char.IsDigit(c);
            }

            return isNum;
        }

        private void finishAllSalesBtn_Click(object sender, EventArgs e)
        {
            if (finishAllSalesBtn.Text == "New Operation")
            {
                numberOfSales.Clear();
                grandDiscount.Clear();
                grandTotal.Clear();
                grandDiscountBGN.Clear();
                grandTotalBGN.Clear();
                selectedCurrency.SelectedIndex = -1;
                listviewSales.Items.Clear();

                article.Text = "";
                unitPrice.Clear();
                quantity.Clear();
                discount.Clear();
                totalAmount.Clear();
                numOfSales = 0;
                grandDiscountValue = 0;
                grandTotalValue = 0;
                grandDiscLabel.ForeColor = Color.Black;
                finishAllSalesBtn.Text = "Finish All Sales";
                totalBtn.Enabled = true;
                article.Enabled = true;
                unitPrice.ReadOnly = false;
                quantity.ReadOnly = false;
                selectDate.Enabled = true;
            }
            else
            {
                string finishSalesMessage = "Conclusion of input sales and calculating the total discount and total amount of all entries.";
                string finishSalesCaption = "Finish Sales";
                result = MessageBox.Show(finishSalesMessage, finishSalesCaption, button);

                numberOfSales.Text = numOfSales.ToString();
                grandDiscount.Text = string.Format("{0:0.00}", grandDiscountValue);
                grandTotal.Text = string.Format("{0:0.00}", grandTotalValue);

                finishAllSalesBtn.Text = "New Operation";
                newSaleBtn.Enabled = false;
                totalBtn.Enabled = true;
                article.Enabled = true;
                unitPrice.ReadOnly = true;
                quantity.ReadOnly = true;

                if (grandDiscountValue > 0)
                {
                    grandDiscLabel.ForeColor = Color.Red;
                }
                else
                {
                    grandDiscLabel.ForeColor = Color.Black;
                }
                discountLabel.ForeColor = Color.Black;

                finishAllSalesBtn.Text = "New Operation";
            }

            numberOfSalesBGN.Text = numberOfSales.Text;

            decimal exchangeRateEUR = 0.51m;
            decimal exchangeRateUSD = 0.64m;

            switch (selectedCurrency.Text)
            {
                case "BGN":
                    currencyLabel.Text = "BGN";
                    grandDiscountBGN.Text = grandDiscount.Text;
                    grandTotalBGN.Text = grandTotal.Text;
                    break;
                case "EUR":
                    decimal grandDiscountEUR = grandDiscountValue * exchangeRateEUR;
                    decimal grandTotalEUR = grandTotalValue * exchangeRateEUR;
                    grandDiscountBGN.Text = string.Format("{0:0.00}", grandDiscountEUR);
                    grandTotalBGN.Text = string.Format("{0:0.00}", grandTotalEUR);
                    currencyLabel.Text = "EUR";
                    break;
                case "USD":
                    decimal grandDiscountUSD = grandDiscountValue * exchangeRateUSD;
                    decimal grandTotalUSD = grandTotalValue * exchangeRateUSD;
                    grandDiscountBGN.Text = string.Format("{0:0.00}", grandDiscountUSD);
                    grandTotalBGN.Text = string.Format("{0:0.00}", grandTotalUSD);
                    currencyLabel.Text = "USD";
                    break;
            }
        }

        private void exitBtn_Click(object sender, EventArgs e)
        {
            string exitMessage = "Exit the application";
            string exitCaption = "Exit";
            result = MessageBox.Show(exitMessage, exitCaption, button);
            this.Close();
        }

        private void unitPrice_MouseHover(object sender, EventArgs e)
        {
            toolTip.Show("Positive value. Required field.", unitPrice);
        }

        private void quantity_MouseHover(object sender, EventArgs e)
        {
            toolTip.Show("Positive whole value. Required field.", quantity);
        }

        private void newSaleBtn_MouseHover(object sender, EventArgs e)
        {
            toolTip.Show("Adds a new sale to the current operation.", newSaleBtn);
        }

        private void totalBtn_MouseHover(object sender, EventArgs e)
        {
            toolTip.Show("Calculates the total sum of the current sale.", totalBtn);
        }

        private void finishAllSalesBtn_MouseHover(object sender, EventArgs e)
        {
            if (finishAllSalesBtn.Text == "New Operation")
            {
                toolTip.Show("Begins a new operation.", finishAllSalesBtn);
            }
            toolTip.Show("Finishes the current operation and calculates grand sums.", finishAllSalesBtn);
        }
    }
}