/*
 * $Id: c2ecc14e0fab785c6f04970ccc9a4dc636e52b16 $
 *
 * This file is part of the iText (R) project.
 * Copyright (c) 1998-2015 iText Group NV
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS
 *
 * 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 Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;

import com.itextpdf.text.error_messages.MessageLocalization;
import com.itextpdf.text.pdf.ICC_Profile;

/**
 * An <CODE>Jpeg</CODE> is the representation of a graphic element (JPEG)
 * that has to be inserted into the document
 *
 * @see		Element
 * @see		Image
 */

public class Jpeg extends Image {
    
    // public static final membervariables
    
    /** This is a type of marker. */
    public static final int NOT_A_MARKER = -1;
    
    /** This is a type of marker. */
    public static final int VALID_MARKER = 0;
    
    /** Acceptable Jpeg markers. */
    public static final int[] VALID_MARKERS = {0xC0, 0xC1, 0xC2};
    
    /** This is a type of marker. */
    public static final int UNSUPPORTED_MARKER = 1;
    
    /** Unsupported Jpeg markers. */
    public static final int[] UNSUPPORTED_MARKERS = {0xC3, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCD, 0xCE, 0xCF};
    
    /** This is a type of marker. */
    public static final int NOPARAM_MARKER = 2;
    
    /** Jpeg markers without additional parameters. */
    public static final int[] NOPARAM_MARKERS = {0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0x01};
    
    /** Marker value */
    public static final int M_APP0 = 0xE0;
    /** Marker value */
    public static final int M_APP2 = 0xE2;
    /** Marker value */
    public static final int M_APPE = 0xEE;
    /** Marker value for Photoshop IRB */
    public static final int M_APPD = 0xED;
    
    /** sequence that is used in all Jpeg files */
    public static final byte JFIF_ID[] = {0x4A, 0x46, 0x49, 0x46, 0x00};
    
    /** sequence preceding Photoshop resolution data */
    public static final byte PS_8BIM_RESO[] = {0x38, 0x42, 0x49, 0x4d, 0x03, (byte) 0xed};
    
    private byte[][] icc;
    // Constructors
    
    Jpeg(Image image) {
        super(image);
    }

    /**
     * Constructs a <CODE>Jpeg</CODE>-object, using an <VAR>url</VAR>.
     *
     * @param		url			the <CODE>URL</CODE> where the image can be found
     * @throws BadElementException
     * @throws IOException
     */
    public Jpeg(URL url) throws BadElementException, IOException {
        super(url);
        processParameters();
    }
    
    /**
     * Constructs a <CODE>Jpeg</CODE>-object from memory.
     *
     * @param		img		the memory image
     * @throws BadElementException
     * @throws IOException
     */
    
    public Jpeg(byte[] img) throws BadElementException, IOException {
        super((URL)null);
        rawData = img;
        originalData = img;
        processParameters();
    }
    
    /**
     * Constructs a <CODE>Jpeg</CODE>-object from memory.
     *
     * @param		img			the memory image.
     * @param		width		the width you want the image to have
     * @param		height		the height you want the image to have
     * @throws BadElementException
     * @throws IOException
     */
    
    public Jpeg(byte[] img, float width, float height) throws BadElementException, IOException {
        this(img);
        scaledWidth = width;
        scaledHeight = height;
    }
    
    // private static methods
    
    /**
     * Reads a short from the <CODE>InputStream</CODE>.
     *
     * @param	is		the <CODE>InputStream</CODE>
     * @return	an int
     * @throws IOException
     */
    private static final int getShort(InputStream is) throws IOException {
        return (is.read() << 8) + is.read();
    }
    
    /**
     * Returns a type of marker.
     *
     * @param	marker      an int
     * @return	a type: <VAR>VALID_MARKER</CODE>, <VAR>UNSUPPORTED_MARKER</VAR> or <VAR>NOPARAM_MARKER</VAR>
     */
    private static final int marker(int marker) {
        for (int i = 0; i < VALID_MARKERS.length; i++) {
            if (marker == VALID_MARKERS[i]) {
                return VALID_MARKER;
            }
        }
        for (int i = 0; i < NOPARAM_MARKERS.length; i++) {
            if (marker == NOPARAM_MARKERS[i]) {
                return NOPARAM_MARKER;
            }
        }
        for (int i = 0; i < UNSUPPORTED_MARKERS.length; i++) {
            if (marker == UNSUPPORTED_MARKERS[i]) {
                return UNSUPPORTED_MARKER;
            }
        }
        return NOT_A_MARKER;
    }
    
    // private methods
    
    /**
     * This method checks if the image is a valid JPEG and processes some parameters.
     * @throws BadElementException
     * @throws IOException
     */
    private void processParameters() throws BadElementException, IOException {
        type = JPEG;
        originalType = ORIGINAL_JPEG;
        InputStream is = null;
        try {
            String errorID;
            if (rawData == null){
                is = url.openStream();
                errorID = url.toString();
            }
            else{
                is = new java.io.ByteArrayInputStream(rawData);
                errorID = "Byte array";
            }
            if (is.read() != 0xFF || is.read() != 0xD8)	{
                throw new BadElementException(MessageLocalization.getComposedMessage("1.is.not.a.valid.jpeg.file", errorID));
            }
            boolean firstPass = true;
            int len;
            while (true) {
                int v = is.read();
                if (v < 0)
                    throw new IOException(MessageLocalization.getComposedMessage("premature.eof.while.reading.jpg"));
                if (v == 0xFF) {
                    int marker = is.read();
                    if (firstPass && marker == M_APP0) {
                        firstPass = false;
                        len = getShort(is);
                        if (len < 16) {
                            Utilities.skip(is, len - 2);
                            continue;
                        }
                        byte bcomp[] = new byte[JFIF_ID.length];
                        int r = is.read(bcomp);
                        if (r != bcomp.length)
                            throw new BadElementException(MessageLocalization.getComposedMessage("1.corrupted.jfif.marker", errorID));
                        boolean found = true;
                        for (int k = 0; k < bcomp.length; ++k) {
                            if (bcomp[k] != JFIF_ID[k]) {
                                found = false;
                                break;
                            }
                        }
                        if (!found) {
                            Utilities.skip(is, len - 2 - bcomp.length);
                            continue;
                        }
                        Utilities.skip(is, 2);
                        int units = is.read();
                        int dx = getShort(is);
                        int dy = getShort(is);
                        if (units == 1) {
                            dpiX = dx;
                            dpiY = dy;
                        }
                        else if (units == 2) {
                            dpiX = (int)(dx * 2.54f + 0.5f);
                            dpiY = (int)(dy * 2.54f + 0.5f);
                        }
                        Utilities.skip(is, len - 2 - bcomp.length - 7);
                        continue;
                    }
                    if (marker == M_APPE) {
                        len = getShort(is) - 2;
                        byte[] byteappe = new byte[len];
                        for (int k = 0; k < len; ++k) {
                            byteappe[k] = (byte)is.read();
                        }
                        if (byteappe.length >= 12) {
                            String appe = new String(byteappe, 0, 5, "ISO-8859-1");
                            if (appe.equals("Adobe")) {
                                invert = true;
                            }
                        }
                        continue;
                    }
                    if (marker == M_APP2) {
                        len = getShort(is) - 2;
                        byte[] byteapp2 = new byte[len];
                        for (int k = 0; k < len; ++k) {
                            byteapp2[k] = (byte)is.read();
                        }
                        if (byteapp2.length >= 14) {
                            String app2 = new String(byteapp2, 0, 11, "ISO-8859-1");
                            if (app2.equals("ICC_PROFILE")) {
                                int order = byteapp2[12] & 0xff;
                                int count = byteapp2[13] & 0xff;
                                // some jpeg producers don't know how to count to 1
                                if (order < 1)
                                    order = 1;
                                if (count < 1)
                                    count = 1;
                                if (icc == null)
                                    icc = new byte[count][];
                                icc[order - 1] = byteapp2;
                            }
                        }
                        continue;
                    }
                    if (marker == M_APPD) {
                    	len = getShort(is) - 2;
                    	byte[] byteappd = new byte[len];
                        for (int k = 0; k < len; k++) {
                            byteappd[k] = (byte)is.read();
                        }
                        // search for '8BIM Resolution' marker
                        int k = 0;
                        for (k = 0; k < len-PS_8BIM_RESO.length; k++) {
                        	boolean found = true;
                        	for (int j = 0; j < PS_8BIM_RESO.length; j++) {
                        		if (byteappd[k+j] != PS_8BIM_RESO[j]) {
                        			found = false;
                        			break;
                        		}
                        	}
                        	if (found)
                        		break;
                        }

                        k+=PS_8BIM_RESO.length;
                        if (k < len-PS_8BIM_RESO.length) {
                        	// "PASCAL String" for name, i.e. string prefix with length byte
                        	// padded to be even length; 2 null bytes if empty
                        	byte namelength = byteappd[k];
                        	// add length byte
                        	namelength++;
                        	// add padding
                        	if (namelength % 2 == 1)
                        		namelength++;
                        	// just skip name
                        	k += namelength;
                        	// size of the resolution data
                        	int resosize = (byteappd[k] << 24) + (byteappd[k+1] << 16) + (byteappd[k+2] << 8) + byteappd[k+3];
                        	// should be 16
                        	if (resosize != 16) {
                        		// fail silently, for now
                        		//System.err.println("DEBUG: unsupported resolution IRB size");
                        		continue;
                        	}
                        	k+=4;
                        	int dx = (byteappd[k] << 8) + (byteappd[k+1] & 0xff);
                        	k+=2;
                        	// skip 2 unknown bytes
                        	k+=2;
                        	int unitsx = (byteappd[k] << 8) + (byteappd[k+1] & 0xff);
                        	k+=2;
                        	// skip 2 unknown bytes
                        	k+=2;
                        	int dy = (byteappd[k] << 8) + (byteappd[k+1] & 0xff);
                        	k+=2;
                        	// skip 2 unknown bytes
                        	k+=2;
                        	int unitsy = (byteappd[k] << 8) + (byteappd[k+1] & 0xff);
                        	
                        	if (unitsx == 1 || unitsx == 2) {
                        		dx = (unitsx == 2 ? (int)(dx * 2.54f + 0.5f) : dx);
                        		// make sure this is consistent with JFIF data
                        		if (dpiX != 0 && dpiX != dx) {
                        			//System.err.println("DEBUG: inconsistent metadata (dpiX: " + dpiX + " vs " + dx + ")");
                        		}
                        		else
                        			dpiX = dx;
                            }
                        	if (unitsy == 1 || unitsy == 2) {
                        		dy = (unitsy == 2 ? (int)(dy * 2.54f + 0.5f) : dy);
                        		// make sure this is consistent with JFIF data
                        		if (dpiY != 0 && dpiY != dy) {
                        			//System.err.println("DEBUG: inconsistent metadata (dpiY: " + dpiY + " vs " + dy + ")");
                        		}
                        		else
                        			dpiY = dy;
                            }
                        }
                        continue;
                    }
                    firstPass = false;
                    int markertype = marker(marker);
                    if (markertype == VALID_MARKER) {
                        Utilities.skip(is, 2);
                        if (is.read() != 0x08) {
                            throw new BadElementException(MessageLocalization.getComposedMessage("1.must.have.8.bits.per.component", errorID));
                        }
                        scaledHeight = getShort(is);
                        setTop(scaledHeight);
                        scaledWidth = getShort(is);
                        setRight(scaledWidth);
                        colorspace = is.read();
                        bpc = 8;
                        break;
                    }
                    else if (markertype == UNSUPPORTED_MARKER) {
                        throw new BadElementException(MessageLocalization.getComposedMessage("1.unsupported.jpeg.marker.2", errorID, String.valueOf(marker)));
                    }
                    else if (markertype != NOPARAM_MARKER) {
                        Utilities.skip(is, getShort(is) - 2);
                    }
                }
            }
        }
        finally {
            if (is != null) {
                is.close();
            }
        }
        plainWidth = getWidth();
        plainHeight = getHeight();
        if (icc != null) {
            int total = 0;
            for (int k = 0; k < icc.length; ++k) {
                if (icc[k] == null) {
                    icc = null;
                    return;
                }
                total += icc[k].length - 14;
            }
            byte[] ficc = new byte[total];
            total = 0;
            for (int k = 0; k < icc.length; ++k) {
                System.arraycopy(icc[k], 14, ficc, total, icc[k].length - 14);
                total += icc[k].length - 14;
            }
            try {
            	ICC_Profile icc_prof = ICC_Profile.getInstance(ficc, colorspace);
            	tagICC(icc_prof);
            }
            catch(IllegalArgumentException e) {
            	// ignore ICC profile if it's invalid.
            }
            icc = null;
        }
    }
}
