//Kod kreskowy BC412
//(c) 2019 by Tomasz Lubinski
//www.algorytm.org

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

namespace Barcodes.BC412
{
    public partial class Form1 : Form
    {
        private readonly static char[] BC412signs = 
        {
            '0', 'R', '9', 'G', 'L', 'V', 'H', 'A', '8', 'E',
            'Z', '4', 'N', 'T', 'S', '1', 'J', '2', 'Q', '6', 
            'C', '7', 'D', 'Y', 'K', 'B', 'U', 'I', 'X', '3', 
            'F', 'W', 'P', '5', 'M'
        };

        private readonly static int[,] BC412Spaces = 
        {
            {1, 1, 1, 5},
            {3, 1, 2, 2},
            {1, 3, 1, 3},
            {2, 1, 2, 3},
            {2, 2, 3, 1},
            {3, 3, 1, 1},
            {2, 1, 3, 2},
            {1, 3, 2, 2},
            {1, 2, 4, 1},
            {1, 5, 1, 1},
            {5, 1, 1, 1},
            {1, 1, 5, 1},
            {2, 3, 2, 1},
            {3, 2, 1, 2},
            {3, 1, 2, 2},
            {1, 1, 2, 4},
            {2, 2, 1, 3},
            {1, 1, 3, 3},
            {3, 1, 1, 3},
            {1, 2, 2, 3},
            {1, 4, 1, 2},
            {1, 2, 3, 2},
            {1, 4, 2, 1},
            {4, 2, 1, 1},
            {2, 2, 2, 2},
            {1, 3, 3, 1},
            {3, 2, 2, 1},
            {2, 1, 4, 1},
            {4, 1, 2, 1},
            {1, 1, 4, 2},
            {2, 1, 1, 4},
            {4, 1, 1, 2},
            {2, 4, 1, 1},
            {1, 2, 1, 4},
            {2, 3, 1, 2}
        };

        private readonly static int start = 2;
        private readonly static int stop = 1;

        /// <summary>
        /// Zainicjuj
        /// </summary>
        public Form1()
        {
            InitializeComponent();
            pictureBox.Image = new Bitmap(pictureBox.Width, pictureBox.Height, PixelFormat.Format24bppRgb);
            System.Drawing.SolidBrush whiteBrush = new System.Drawing.SolidBrush(System.Drawing.Color.White);
            System.Drawing.Graphics graphics = Graphics.FromImage(pictureBox.Image);
            graphics.FillRectangle(whiteBrush, new Rectangle(0, 0, pictureBox.Width, pictureBox.Height));
            pictureBox.Refresh();
            whiteBrush.Dispose();
            graphics.Dispose();
        }

        /// <summary>
        /// Sprawdza czy podany txt mozna zakodowac BC412
        /// </summary>
        /// <param name="txt">tekst do zakodowania</param>
        /// <returns>true jezeli mozna zakodowac, false w przeciwnym razie</returns>
        public bool check(string txt)
        {
            for (int i = 0; i < txt.Length; i++)
            {
                if (checkLetter(txt[i]) == false)
                    return false;
            }
            return true;
        }

        /// <summary>
        /// Sprawdza czy podany znak mozna zakodowac BC412
        /// </summary>
        /// <param name="ch">znak do zakodowania</param>
        /// <returns>true jezeli mozna zakodowac, false w przeciwnym razie</returns>
        private bool checkLetter(char ch)
        {
            for (int i = 0; i < BC412signs.Length; i++)
            {
                if (BC412signs[i] == ch)
                    return true;
            }
            return false;
        }

        /// <summary>
        /// Zwraca wartosc danego znaku
        /// </summary>
        /// <param name="ch">znak</param>
        /// <returns>wartosc danego znaku</returns>
        private int getLetterValue(char ch)
        {
            for (int i = 0; i < BC412signs.Length; i++)
                if (BC412signs[i] == ch)
                    return i;

            return -1;
        }

        /// <summary>
        /// Zwraca cyfre kontrolna dla danego ciagu
        /// </summary>
        /// <param name="code">kodowany ciag</param>
        /// <returns>cyfra kontrolna dla danego ciagu</returns>
        private int checkDigit(string code)
        {
            int sum = 0;
            for (int i = 0; i < code.Length; i++)
                sum += getLetterValue(code[i]);

            return (sum % 35);
        }

        /// <summary>
        /// Generuj BC412
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Generate_Click(object sender, EventArgs e)
        {
            //Zainicjuj narzedzia do rysowania
            System.Drawing.SolidBrush whiteBrush = new System.Drawing.SolidBrush(System.Drawing.Color.White);
            System.Drawing.SolidBrush blackBrush = new System.Drawing.SolidBrush(System.Drawing.Color.Black);
            System.Drawing.Graphics graphics = Graphics.FromImage(pictureBox.Image);
            Font drawFont = new Font("Arial", 10);

            //Wyczysc obszar rysowania
            graphics.FillRectangle(whiteBrush, new Rectangle(0, 0, pictureBox.Width, pictureBox.Height));

            //Sprawdz czy podany ciag mozna zakodowac
            string code = Code.Text;
            //Zamien wszystkie wystapienia 'O' na '0'
            code = code.Replace('O', '0');
            if (check(code) == false)
            {
                MessageBox.Show("Nieprawidłowe znaki!", "Bład", MessageBoxButtons.OK, MessageBoxIcon.Error);
                return;
            }

            //Wygeneruj i narysuj kod
            int[] bars = generateBars(code);
            int pos = 10;
            for (int i = 0; i < bars.Length; i++)
            {
                //Narysuj pasek i przesun sie o jego wielokrotnosc
                graphics.FillRectangle(blackBrush, pos, 10, 2, 90);
                pos += 2 + bars[i]*2;
            }

            //Wypisz kodowany ciag pod kodem kreskowym
            for (int i = 0; i < code.Length; i++)
            {
                graphics.DrawString(code.Substring(i, 1), drawFont, blackBrush, i * 24 + 20, 102);
            }

            //Odswiez
            pictureBox.Refresh();

            //Zwolinij zasoby
            whiteBrush.Dispose();
            blackBrush.Dispose();
            graphics.Dispose();
        }

        /// <summary>
        /// Generuje kod kreskowy
        /// </summary>
        /// <param name="code">string do zakodowania kodem kreskowym</param>
        /// <returns>zwraca szerokosc kolejnych przerw</returns>
        private int[] generateBars(string code)
        {
            int[] bars = new int[4 * (code.Length + 1) + 2];

            //Dodaj znak start/stop
            bars[0] = start;

            //Dodaj kolejne znaki
            for (int i = 0; i < code.Length; i++)
            {
                int letterValue = getLetterValue(code[i]);
                for (int j = 0; j < 4; j++)
                {
                    bars[i * 4 + 1 + j] = BC412Spaces[letterValue, j];
                }
            }

            //Dodaj cyfre kontrolna
            int checkDigitValue = checkDigit(code);
            for (int j = 0; j < 4; j++)
            {
                bars[4 * code.Length + 1 + j] = BC412Spaces[checkDigitValue, j];
            }

            //Dodaj znak start/stop
            bars[4 * (code.Length + 1) + 1] = stop;
            
            return bars;
        }
    }
}