EmbroideryReader/PesFile/PesFile.cs

/*
Embroidery Reader - an application to view .pes embroidery designs

Copyright (C) 2016 Nathan Crawford
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.

A copy of the full GPL 2 license can be found in the docs directory.
You can contact me at http://www.njcrawford.com/contact/.
*/

using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;

namespace PesFile
{
    public class PECFormatException : System.Exception
    {
        public PECFormatException(string message) : base(message) { }
    }

    public class PesFile
    {
        private int imageWidth;
        private int imageHeight;
        private string _filename;
        public List<StitchBlock> blocks = new List<StitchBlock>();
        public List<Tuple<int, int>> colorTable = new List<Tuple<int, int>>();
        private Int64 startStitches = 0;
        private Point translateStart;
        private UInt16 pesVersion;


        // If set to true, this variable means we couldn't figure out some or
        // all of the colors and white will be used instead of those colors.
        private bool colorWarning = false;

        private bool formatWarning = false;

        public PesFile(string filename)
        {
            OpenFile(filename);
        }

        // Returns an Int16 representation of the 12 bit signed int contained in
        // high and low bytes
        private Int16 get12Bit2sComplement(byte high, byte low)
        {
            Int32 retval;

            // Get the bottom 4 bits of the high byte
            retval = high & 0x0f;

            // Shift those bits up where they belong
            retval = retval << 8;

            // Add in the bottom 8 bits
            retval += low;

            // Check for a negative number (check if 12th bit is 1)
            if ((retval & 0x0800) == 0x0800)
            {
                // Make the number negative by subtracting 4096, which is the
                // number of values a 12 bit integer can represent.
                // This is a shortcut for getting the 2's complement value.
                retval -= 4096;
            }

            return (Int16)retval;
        }

        // Returns a signed byte representation of the 7 bit signed int contained
        // in b.
        private SByte get7Bit2sComplement(byte b)
        {
            SByte retval;

            // Ignore the 8th bit. (make sure it's 0)
            b &= 0x7f;

            // Check for a negative number (check if 7th bit is 1)
            if ((b & 0x40) == 0x40)
            {
                // Make the number negative by subtracting 128, which is the
                // number of values a 7 bit integer can represent.
                // This is a shortcut for getting the 2's complement value.
                retval = (SByte)(b - 128);
            }
            else
            {
                // Positive number - no modification needed
                retval = (SByte)b;
            }

            return retval;
        }

        private void OpenFile(string filename)
        {
            _filename = filename;

            // The using statements ensure fileIn is closed, no matter how the statement is exited.
            // Open the file in read-only mode, but allow read-write sharing. This prevents a case where opening
            // the file read-only with read sharing could fail because some other application already has it
            // open with read-write access even though it's not writing to the file. (I suspect some antivirus
            // programs may be doing this) Using this mode may allow reading half-written files, but I don't expect
            // that will be an issue with PES designs, since they're generally written once when downloaded and left
            // alone after that.
            using (FileStream fileStreamIn = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            {
                using (BinaryReader fileIn = new BinaryReader(fileStreamIn))
                {
                    string startFileSig = "";
                    for (int i = 0; i < 4; i++) // 4 bytes
                    {
                        // This needs to be read as a byte, since characters can be multiple bytes depending on encoding
                        startFileSig += (char)fileIn.ReadByte();
                    }
                    if (startFileSig != "#PES")
                    {
                        // This is not a file that we can read
                        throw new PECFormatException("Missing #PES at beginning of file");
                    }

                    // PES version
                    string versionString = "";
                    for (int i = 0; i < 4; i++) // 4 bytes
                    {
                        // This needs to be read as a byte, since characters can be multiple bytes depending on encoding
                        versionString += (char)fileIn.ReadByte();
                    }
                    if (!UInt16.TryParse(versionString, out pesVersion))
                    {
                        // This is not a file that we can read
                        throw new PECFormatException("PES version is not the correct format");
                    }

                    int pecstart = fileIn.ReadInt32();
                    // Sanity check on PEC start position
                    if (fileIn.BaseStream.Length < (pecstart + 532))
                    {
                        // This file is probably truncated
                        throw new PECFormatException("File appears to be truncated (PEC section is beyond end of file)");
                    }

                    // Read number of colors in this design
                    fileIn.BaseStream.Position = pecstart + 48;
                    int numColors = fileIn.ReadByte() + 1;
                    List<byte> colorList = new List<byte>();
                    for (int x = 0; x < numColors; x++)
                    {
                        colorList.Add(fileIn.ReadByte());
                    }

                    // Read stitch data
                    fileIn.BaseStream.Position = pecstart + 532;
                    bool thisPartIsDone = false;
                    StitchBlock curBlock;
                    int prevX = 0;
                    int prevY = 0;
                    int maxX = 0;
                    int minX = 0;
                    int maxY = 0;
                    int minY = 0;
                    int colorNum = -1;
                    int colorIndex = 0;
                    List<Stitch> tempStitches = new List<Stitch>();
                    while (!thisPartIsDone)
                    {
                        byte val1;
                        byte val2;
                        val1 = fileIn.ReadByte();
                        val2 = fileIn.ReadByte();
                        if (val1 == 0xff && val2 == 0x00)
                        {
                            //end of stitches
                            thisPartIsDone = true;

                            //add the last block
                            curBlock = new StitchBlock();
                            curBlock.stitches = new Stitch[tempStitches.Count];
                            tempStitches.CopyTo(curBlock.stitches);
                            curBlock.stitchesTotal = tempStitches.Count;
                            colorNum++;
                            colorIndex = colorList[colorNum];
                            curBlock.colorIndex = colorIndex;
                            curBlock.color = getColorFromIndex(colorIndex);
                            blocks.Add(curBlock);
                        }
                        else if (val1 == 0xfe && val2 == 0xb0)
                        {
                            //color switch, start a new block

                            curBlock = new StitchBlock();
                            curBlock.stitches = new Stitch[tempStitches.Count];
                            tempStitches.CopyTo(curBlock.stitches);
                            curBlock.stitchesTotal = tempStitches.Count;
                            colorNum++;
                            colorIndex = colorList[colorNum];
                            curBlock.colorIndex = colorIndex;
                            curBlock.color = getColorFromIndex(colorIndex);
                            //read useless(?) byte
                            // The value of this 'useless' byte seems to alternate
                            // between 2 and 1 for every other block. The only
                            // exception I've noted is the last block which appears
                            // to always be 0.
                            curBlock.unknownStartByte = fileIn.ReadByte();
                            blocks.Add(curBlock);

                            tempStitches = new List<Stitch>();
                        }
                        else
                        {
                            int extraBits1 = 0x00;
                            if ((val1 & 0x80) == 0x80)
                            {
                                // Save the top 4 bits to output with debug info
                                // The top bit means this is a 12 bit value, but I don't know what the next 3 bits mean.
                                // The only combinations I've observed in real files are 0x80, 0x90 and 0xa0. 0x80 is
                                // used for the bulk of stitches, with a few 0x80 and/or 0x90 in most files.
                                extraBits1 = val1 & 0xf0;
                            }

                            int deltaX = 0;
                            int deltaY = 0;
                            if ((val1 & 0x80) == 0x80)
                            {
                                // This is a 12-bit int. Allows for needle movement
                                // of up to +2047 or -2048.
                                deltaX = get12Bit2sComplement(val1, val2);

                                // The X value used both bytes, so read next byte
                                // for Y value.
                                val1 = fileIn.ReadByte();
                            }
                            else
                            {
                                // This is a 7-bit int. Allows for needle movement
                                // of up to +63 or -64.
                                deltaX = get7Bit2sComplement(val1);

                                // The X value only used 1 byte, so copy the second
                                // to to the first for Y value.
                                val1 = val2;
                            }

                            int extraBits2 = 0x00;
                            if ((val1 & 0x80) == 0x80)
                            {
                                // Save the top 4 bits to output with debug info
                                // The top bit means this is a 12 bit value, but I don't know what the next 3 bits mean.
                                // In all the files I've checked, extraBits2 is the same as extraBits1.
                                extraBits2 = val1 & 0xf0;
                            }

                            if ((val1 & 0x80) == 0x80)
                            {
                                // This is a 12-bit int. Allows for needle movement
                                // of up to +2047 or -2048.
                                // Read in the next byte to get the full value
                                val2 = fileIn.ReadByte();
                                deltaY = get12Bit2sComplement(val1, val2);
                            }
                            else
                            {
                                // This is a 7-bit int. Allows for needle movement
                                // of up to +63 or -64.
                                deltaY = get7Bit2sComplement(val1);
                                // Finished reading data for this stitch, no more
                                // bytes needed.
                            }
                            // Add stitch to list
                            tempStitches.Add(
                                new Stitch(
                                    new Point(prevX, prevY),
                                    new Point(prevX + deltaX, prevY + deltaY),
                                    extraBits1,
                                    extraBits2
                                )
                            );

                            // Calculate new "previous" position
                            prevX = prevX + deltaX;
                            prevY = prevY + deltaY;

                            // Update maximum distances
                            if (prevX > maxX)
                            {
                                maxX = prevX;
                            }
                            else if (prevX < minX)
                            {
                                minX = prevX;
                            }

                            if (prevY > maxY)
                            {
                                maxY = prevY;
                            }
                            else if (prevY < minY)
                            {
                                minY = prevY;
                            }
                        }
                    }
                    imageWidth = maxX - minX;
                    imageHeight = maxY - minY;
                    translateStart.X = -minX;
                    translateStart.Y = -minY;
                }
            }
        }

        public int GetWidth()
        {
            return imageWidth;
        }

        public int GetHeight()
        {
            return imageHeight;
        }

        public string GetFileName()
        {
            if (_filename == null)
            {
                return "";
            }
            else
            {
                return _filename;
            }
        }

        // Returns the path of the file it saved debug info to
        public string saveDebugInfo()
        {
            string retval = System.IO.Path.ChangeExtension(_filename, ".txt");
            System.IO.StreamWriter outfile = new System.IO.StreamWriter(retval);
            outfile.Write(getDebugInfo());
            outfile.Close();
            return retval;
        }

        public string getDebugInfo()
        {
            System.IO.StringWriter outfile = new System.IO.StringWriter();
            outfile.WriteLine("PES header");
            outfile.WriteLine("PES version:\t" + pesVersion);

            outfile.WriteLine("stitches start: " + startStitches.ToString());
            outfile.WriteLine("block info");
            outfile.WriteLine("number\tcolor\tstitches");
            for (int i = 0; i < this.blocks.Count; i++)
            {
                outfile.WriteLine((i + 1).ToString() + "\t" + blocks[i].colorIndex.ToString() + "\t" + blocks[i].stitchesTotal.ToString());
            }
            outfile.WriteLine("color table");
            outfile.WriteLine("number\ta\tb");
            for (int i = 0; i < colorTable.Count; i++)
            {
                outfile.WriteLine((i + 1).ToString() + "\t" + colorTable[i].Item1.ToString() + ", " + colorTable[i].Item2.ToString());
            }
            if (blocks.Count > 0)
            {
                outfile.WriteLine("Extended stitch debug info");
                for (int blocky = 0; blocky < blocks.Count; blocky++)
                {
                    outfile.WriteLine("block " + (blocky + 1).ToString() + " start (color index " + blocks[blocky].colorIndex + ")");
                    outfile.WriteLine("unknown start byte: " + blocks[blocky].unknownStartByte.ToString("X2"));
                    for (int stitchy = 0; stitchy < blocks[blocky].stitches.Length; stitchy++)
                    {
                        string tempLine = blocks[blocky].stitches[stitchy].a.ToString() + " - " + blocks[blocky].stitches[stitchy].b.ToString();
                        if(blocks[blocky].stitches[stitchy].extraBits1 != 0x00)
                        {
                            tempLine += " (extra bits 1: " + blocks[blocky].stitches[stitchy].extraBits1.ToString("X2") + ")";
                        }
                        if (blocks[blocky].stitches[stitchy].extraBits2 != 0x00)
                        {
                            tempLine += " (extra bits 2: " + blocks[blocky].stitches[stitchy].extraBits2.ToString("X2") + ")";
                        }
                        outfile.WriteLine(tempLine);
                    }
                }
            }
            outfile.Close();
            return outfile.ToString();
        }

        public bool getColorWarning()
        {
            return colorWarning;
        }

        public bool getFormatWarning()
        {
            return formatWarning;
        }

        private Color getColorFromIndex(int index)
        {
            if(index >= 1 && index <= 64)
            {
            	return Color.FromArgb(
            		PesColors.colorMap[index,0],
            		PesColors.colorMap[index,1],
            		PesColors.colorMap[index,2]
            	);
            }
            else
            {
             colorWarning = true;
            	return Color.White;
            }
        }

        public Bitmap designToBitmap(Single threadThickness, bool filterUglyStitches, double filterUglyStitchesThreshold, float scale)
        {
            Bitmap DrawArea;
            Graphics xGraph;
            int imageWidth = (int)((GetWidth() + (threadThickness * 2)) * scale);
            int imageHeight = (int)((GetHeight() + (threadThickness * 2)) * scale);
            float tempThreadThickness = threadThickness * scale;

            DrawArea = new Bitmap(imageWidth, imageHeight);
            using (xGraph = Graphics.FromImage(DrawArea))
            {
                int translateX = (int)(translateStart.X * scale);
                int translateY = (int)(translateStart.Y * scale);
                xGraph.TranslateTransform(tempThreadThickness + translateX, tempThreadThickness + translateY);
                
                // Draw smoother lines
                xGraph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                for (int i = 0; i < blocks.Count; i++)
                {
                    using (Pen tempPen = new Pen(blocks[i].color, tempThreadThickness))
                    {
                        tempPen.StartCap = System.Drawing.Drawing2D.LineCap.Round;
                        tempPen.EndCap = System.Drawing.Drawing2D.LineCap.Round;
                        tempPen.LineJoin = System.Drawing.Drawing2D.LineJoin.Round;

                        foreach (Stitch thisStitch in blocks[i].stitches)
                        {
                            if (filterUglyStitches && // Check for filter ugly stitches option
                                !formatWarning && // Only filter stitches if we think we understand the format
                                thisStitch.calcLength() > filterUglyStitchesThreshold) // Check stitch length
                            {
                                // This stitch is too long, so skip it
                                continue;
                            }
                            Point tempA = new Point((int)(thisStitch.a.X * scale), (int)(thisStitch.a.Y * scale));
                            Point tempB = new Point((int)(thisStitch.b.X * scale), (int)(thisStitch.b.Y * scale));
                            xGraph.DrawLine(tempPen, tempA, tempB);
                        }
                    }
                }
            }

            return DrawArea;
        }
    }
}