/*

 * Copyright (c) 2002, 2004, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package org.apidesign.javap;

import java.io.*;

/**

 * Central data repository of the Java Disassembler.

 * Stores all the information in java class file.

 *

 * @author  Sucheta Dambalkar (Adopted code from jdis)

 */

public final class ClassData implements RuntimeConstants {

    private int magic;

    private int minor_version;

    private int major_version;

    private int cpool_count;

    private Object cpool[];

    private int access;

    private int this_class = 0;;

    private int super_class;

    private int interfaces_count;

    private int[] interfaces = new int[0];;

    private int fields_count;

    private FieldData[] fields;

    private int methods_count;

    private MethodData[] methods;

    private InnerClassData[] innerClasses;

    private int attributes_count;

    private AttrData[] attrs;

    private String classname;

    private String superclassname;

    private int source_cpx=0;

    private byte tags[];

    private Hashtable indexHashAscii = new Hashtable();

    private String pkgPrefix="";

    private int pkgPrefixLen=0;

    /**

     * Read classfile to disassemble.

     */

    public ClassData(InputStream infile) throws IOException {

        this.read(new DataInputStream(infile));

    }

    /**

     * Reads and stores class file information.

     */

    public void read(DataInputStream in) throws IOException {

        // Read the header

        magic = in.readInt();

        if (magic != JAVA_MAGIC) {

            throw new ClassFormatError("wrong magic: " +

                                       toHex(magic) + ", expected " +

                                       toHex(JAVA_MAGIC));

        }

        minor_version = in.readShort();

        major_version = in.readShort();

        if (major_version != JAVA_VERSION) {

        }

        // Read the constant pool

        readCP(in);

        access = in.readUnsignedShort();

        this_class = in.readUnsignedShort();

        super_class = in.readUnsignedShort();

        //Read interfaces.

        interfaces_count = in.readUnsignedShort();

        if(interfaces_count > 0){

            interfaces = new int[interfaces_count];

        }

        for (int i = 0; i < interfaces_count; i++) {

            interfaces[i]=in.readShort();

        }

        // Read the fields

        readFields(in);

        // Read the methods

        readMethods(in);

        // Read the attributes

        attributes_count = in.readUnsignedShort();

        attrs=new AttrData[attributes_count];

        for (int k = 0; k < attributes_count; k++) {

            int name_cpx=in.readUnsignedShort();

            if (getTag(name_cpx)==CONSTANT_UTF8

                && getString(name_cpx).equals("SourceFile")

                ){      if (in.readInt()!=2)

                    throw new ClassFormatError("invalid attr length");

                source_cpx=in.readUnsignedShort();

                AttrData attr=new AttrData(this);

                attr.read(name_cpx);

                attrs[k]=attr;

            } else if (getTag(name_cpx)==CONSTANT_UTF8

                       && getString(name_cpx).equals("InnerClasses")

                       ){       int length=in.readInt();

                       int num=in.readUnsignedShort();

                       if (2+num*8 != length)

                           throw new ClassFormatError("invalid attr length");

                       innerClasses=new InnerClassData[num];

                       for (int j = 0; j < num; j++) {

                           InnerClassData innerClass=new InnerClassData(this);

                           innerClass.read(in);

                           innerClasses[j]=innerClass;

                       }

                       AttrData attr=new AttrData(this);

                       attr.read(name_cpx);

                       attrs[k]=attr;

            } else {

                AttrData attr=new AttrData(this);

                attr.read(name_cpx, in);

                attrs[k]=attr;

            }

        }

        in.close();

    } // end ClassData.read()

    /**

     * Reads and stores constant pool info.

     */

    void readCP(DataInputStream in) throws IOException {

        cpool_count = in.readUnsignedShort();

        tags = new byte[cpool_count];

        cpool = new Object[cpool_count];

        for (int i = 1; i < cpool_count; i++) {

            byte tag = in.readByte();

            switch(tags[i] = tag) {

            case CONSTANT_UTF8:

                String str=in.readUTF();

                indexHashAscii.put(cpool[i] = str, new Integer(i));

                break;

            case CONSTANT_INTEGER:

                cpool[i] = new Integer(in.readInt());

                break;

            case CONSTANT_FLOAT:

                cpool[i] = new Float(in.readFloat());

                break;

            case CONSTANT_LONG:

                cpool[i++] = new Long(in.readLong());

                break;

            case CONSTANT_DOUBLE:

                cpool[i++] = new Double(in.readDouble());

                break;

            case CONSTANT_CLASS:

            case CONSTANT_STRING:

                cpool[i] = new CPX(in.readUnsignedShort());

                break;

            case CONSTANT_FIELD:

            case CONSTANT_METHOD:

            case CONSTANT_INTERFACEMETHOD:

            case CONSTANT_NAMEANDTYPE:

                cpool[i] = new CPX2(in.readUnsignedShort(), in.readUnsignedShort());

                break;

            case 0:

            default:

                throw new ClassFormatError("invalid constant type: " + (int)tags[i]);

            }

        }

    }

    /**

     * Reads and strores field info.

     */

    protected void readFields(DataInputStream in) throws IOException {

        int fields_count = in.readUnsignedShort();

        fields=new FieldData[fields_count];

        for (int k = 0; k < fields_count; k++) {

            FieldData field=new FieldData(this);

            field.read(in);

            fields[k]=field;

        }

    }

    /**

     * Reads and strores Method info.

     */

    protected void readMethods(DataInputStream in) throws IOException {

        int methods_count = in.readUnsignedShort();

        methods=new MethodData[methods_count];

        for (int k = 0; k < methods_count ; k++) {

            MethodData method=new MethodData(this);

            method.read(in);

            methods[k]=method;

        }

    }

    /**

     * get a string

     */

    public String getString(int n) {

        if (n == 0) {

            return null; 

        } else {

            return (String)cpool[n];

        }

    }

    /**

     * get the type of constant given an index

     */

    public byte getTag(int n) {

        try{

            return tags[n];

        } catch (ArrayIndexOutOfBoundsException e) {

            return (byte)100;

        }

    }

    static final String hexString="0123456789ABCDEF";

    public static char hexTable[]=hexString.toCharArray();

    static String toHex(long val, int width) {

        StringBuffer s = new StringBuffer();

        for (int i=width-1; i>=0; i--)

            s.append(hexTable[((int)(val>>(4*i)))&0xF]);

        return "0x"+s.toString();

    }

    static String toHex(long val) {

        int width;

        for (width=16; width>0; width--) {

            if ((val>>(width-1)*4)!=0) break;

        }

        return toHex(val, width);

    }

    static String toHex(int val) {

        int width;

        for (width=8; width>0; width--) {

            if ((val>>(width-1)*4)!=0) break;

        }

        return toHex(val, width);

    }

    /**

     * Returns the name of this class.

     */

    public String getClassName() {

        String res=null;

        if (this_class==0) {

            return res;

        }

        int tcpx;

        try {

            if (tags[this_class]!=CONSTANT_CLASS) {

                return res; //"<CP["+cpx+"] is not a Class> ";

            }

            tcpx=((CPX)cpool[this_class]).cpx;

        } catch (ArrayIndexOutOfBoundsException e) {

            return res; // "#"+cpx+"// invalid constant pool index";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

        try {

            return (String)(cpool[tcpx]);

        } catch (ArrayIndexOutOfBoundsException e) {

            return  res; // "class #"+scpx+"// invalid constant pool index";

        } catch (ClassCastException e) {

            return  res; // "class #"+scpx+"// invalid constant pool reference";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

    }

    /**

     * Returns the name of class at perticular index.

     */

    public String getClassName(int cpx) {

        String res="#"+cpx;

        if (cpx==0) {

            return res;

        }

        int scpx;

        try {

            if (tags[cpx]!=CONSTANT_CLASS) {

                return res; //"<CP["+cpx+"] is not a Class> ";

            }

            scpx=((CPX)cpool[cpx]).cpx;

        } catch (ArrayIndexOutOfBoundsException e) {

            return res; // "#"+cpx+"// invalid constant pool index";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

        res="#"+scpx;

        try {

            return (String)(cpool[scpx]);

        } catch (ArrayIndexOutOfBoundsException e) {

            return  res; // "class #"+scpx+"// invalid constant pool index";

        } catch (ClassCastException e) {

            return  res; // "class #"+scpx+"// invalid constant pool reference";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

    }

    public int getAccessFlags() {

        return access;

    }

    /**

     * Returns true if it is a class

     */

    public boolean isClass() {

        if((access & ACC_INTERFACE) == 0) return true;

        return false;

    }

    /**

     * Returns true if it is a interface.

     */

    public boolean isInterface(){

        if((access & ACC_INTERFACE) != 0) return true;

        return false;

    }

    /**

     * Returns true if this member is public, false otherwise.

     */

    public boolean isPublic(){

        return (access & ACC_PUBLIC) != 0;

    }

    /**

     * Returns the access of this class or interface.

     */

    public String[] getAccess(){

        Vector v = new Vector();

        if ((access & ACC_PUBLIC)   !=0) v.addElement("public");

        if ((access & ACC_FINAL)    !=0) v.addElement("final");

        if ((access & ACC_ABSTRACT) !=0) v.addElement("abstract");

        String[] accflags = new String[v.size()];

        v.copyInto(accflags);

        return accflags;

    }

    /**

     * Returns list of innerclasses.

     */

    public InnerClassData[] getInnerClasses(){

        return innerClasses;

    }

    /**

     * Returns list of attributes.

     */

    final AttrData[] getAttributes(){

        return attrs;

    }

    public byte[] findAnnotationData(boolean classRetention) {

        String n = classRetention ?

            "RuntimeInvisibleAnnotations" : // NOI18N

            "RuntimeVisibleAnnotations"; // NOI18N

        return findAttr(n, attrs);

    }

    /**

     * Returns true if superbit is set.

     */

    public boolean isSuperSet(){

        if ((access & ACC_SUPER)   !=0) return true;

        return false;

    }

    /**

     * Returns super class name.

     */

    public String getSuperClassName(){

        String res=null;

        if (super_class==0) {

            return res;

        }

        int scpx;

        try {

            if (tags[super_class]!=CONSTANT_CLASS) {

                return res; //"<CP["+cpx+"] is not a Class> ";

            }

            scpx=((CPX)cpool[super_class]).cpx;

        } catch (ArrayIndexOutOfBoundsException e) {

            return res; // "#"+cpx+"// invalid constant pool index";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

        try {

            return (String)(cpool[scpx]);

        } catch (ArrayIndexOutOfBoundsException e) {

            return  res; // "class #"+scpx+"// invalid constant pool index";

        } catch (ClassCastException e) {

            return  res; // "class #"+scpx+"// invalid constant pool reference";

        } catch (Throwable e) {

            return res; // "#"+cpx+"// ERROR IN DISASSEMBLER";

        }

    }

    /**

     * Returns list of super interfaces.

     */

    public String[] getSuperInterfaces(){

        String interfacenames[] = new String[interfaces.length];

        int interfacecpx = -1;

        for(int i = 0; i < interfaces.length; i++){

            interfacecpx=((CPX)cpool[interfaces[i]]).cpx;

            interfacenames[i] = (String)(cpool[interfacecpx]);

        }

        return interfacenames;

    }

    /**

     * Returns string at prticular constant pool index.

     */

    public String getStringValue(int cpoolx) {

        try {

            return ((String)cpool[cpoolx]);

        } catch (ArrayIndexOutOfBoundsException e) {

            return "//invalid constant pool index:"+cpoolx;

        } catch (ClassCastException e) {

            return "//invalid constant pool ref:"+cpoolx;

        }

    }

    /**

     * Returns list of field info.

     */

    public  FieldData[] getFields(){

        return fields;

    }

    /**

     * Returns list of method info.

     */

    public  MethodData[] getMethods(){

        return methods;

    }

    /**

     * Returns constant pool entry at that index.

     */

    public CPX2 getCpoolEntry(int cpx){

        return ((CPX2)(cpool[cpx]));

    }

    public Object getCpoolEntryobj(int cpx){

        return (cpool[cpx]);

    }

    /**

     * Returns index of this class.

     */

    public int getthis_cpx(){

        return this_class;

    }

    /**

     * Returns string at that index.

     */

    public String StringValue(int cpx) {

        return stringValue(cpx, false);

    }

    public String stringValue(int cpx, boolean textual) {

        return stringValue(cpx, textual, null);

    }

    public String stringValue(int cpx, String[] classRefs) {

        return stringValue(cpx, true, classRefs);

    }

    private String stringValue(int cpx, boolean textual, String[] refs) {

        if (cpx==0) return "#0";

        int tag;

        Object x;

        String suffix="";

        try {

            tag=tags[cpx];

            x=cpool[cpx];

        } catch (IndexOutOfBoundsException e) {

            return "<Incorrect CP index:"+cpx+">";

        }

        if (x==null) return "<NULL>";

        switch (tag) {

        case CONSTANT_UTF8: {

            if (!textual) {

                return (String)x;

            }

            StringBuilder sb=new StringBuilder();

            String s=(String)x;

            for (int k=0; k<s.length(); k++) {

                char c=s.charAt(k);

                switch (c) {

                case '\\': sb.append('\\').append('\\'); break;

                case '\t': sb.append('\\').append('t'); break;

                case '\n': sb.append('\\').append('n'); break;

                case '\r': sb.append('\\').append('r'); break;

                case '\"': sb.append('\\').append('\"'); break;

                default: sb.append(c);

                }

            }

            return sb.toString();

        }

        case CONSTANT_DOUBLE: {

            Double d=(Double)x;

            String sd=d.toString();

            if (textual) {

                return sd;

            }

            return sd+"d";

        }

        case CONSTANT_FLOAT: {

            Float f=(Float)x;

            String sf=(f).toString();

            if (textual) {

                return sf;

            }

            return sf+"f";

        }

        case CONSTANT_LONG: {

            Long ln = (Long)x;

            if (textual) {

                return ln.toString();

            }

            return ln.toString()+'l';

        }

        case CONSTANT_INTEGER: {

            Integer in = (Integer)x;

            return in.toString();

        }

        case CONSTANT_CLASS:

            String jn = getClassName(cpx);

            if (textual) {

                if (refs != null) {

                    refs[0] = jn;

                }

                return jn;

            }

            return javaName(jn);

        case CONSTANT_STRING:

            String sv = stringValue(((CPX)x).cpx, textual);

            if (textual) {

                return '"' + sv + '"';

            } else {

                return sv;

            }

        case CONSTANT_FIELD:

        case CONSTANT_METHOD:

        case CONSTANT_INTERFACEMETHOD:

            //return getShortClassName(((CPX2)x).cpx1)+"."+StringValue(((CPX2)x).cpx2);

             return javaName(getClassName(((CPX2)x).cpx1))+"."+StringValue(((CPX2)x).cpx2);

        case CONSTANT_NAMEANDTYPE:

            return getName(((CPX2)x).cpx1)+":"+StringValue(((CPX2)x).cpx2);

        default:

            return "UnknownTag"; //TBD

        }

    }

    /**

     * Returns resolved java type name.

     */

    public String javaName(String name) {

        if( name==null) return "null";

        int len=name.length();

        if (len==0) return "\"\"";

        int cc='/';

    fullname: { // xxx/yyy/zzz

            int cp;

            for (int k=0; k<len; k += Character.charCount(cp)) {

                cp=name.codePointAt(k);

                if (cc=='/') {

                    if (!isJavaIdentifierStart(cp)) break fullname;

                } else if (cp!='/') {

                    if (!isJavaIdentifierPart(cp)) break fullname;

                }

                cc=cp;

            }

            return name;

        }

        return "\""+name+"\"";

    }

    public String getName(int cpx) {

        String res;

        try {

            return javaName((String)cpool[cpx]); //.replace('/','.');

        } catch (ArrayIndexOutOfBoundsException e) {

            return "<invalid constant pool index:"+cpx+">";

        } catch (ClassCastException e) {

            return "<invalid constant pool ref:"+cpx+">";

        }

    }

    /**

     * Returns unqualified class name.

     */

    public String getShortClassName(int cpx) {

        String classname=javaName(getClassName(cpx));

        pkgPrefixLen=classname.lastIndexOf("/")+1;

        if (pkgPrefixLen!=0) {

            pkgPrefix=classname.substring(0,pkgPrefixLen);

            if (classname.startsWith(pkgPrefix)) {

                return classname.substring(pkgPrefixLen);

            }

        }

        return classname;

    }

    /**

     * Returns source file name.

     */

    public String getSourceName(){

        return getName(source_cpx);

    }

    /**

     * Returns package name.

     */

    public String getPkgName(){

        String classname=getClassName(this_class);

        pkgPrefixLen=classname.lastIndexOf("/")+1;

        if (pkgPrefixLen!=0) {

            pkgPrefix=classname.substring(0,pkgPrefixLen);

            return("package  "+pkgPrefix.substring(0,pkgPrefixLen-1)+";\n");

        }else return null;

    }

    /**

     * Returns total constant pool entry count.

     */

    public int getCpoolCount(){

        return cpool_count;

    }

    /**

     * Returns minor version of class file.

     */

    public int getMinor_version(){

        return minor_version;

    }

    /**

     * Returns major version of class file.

     */

    public int getMajor_version(){

        return major_version;

    }

    private boolean isJavaIdentifierStart(int cp) {

        return ('a' <= cp && cp <= 'z') || ('A' <= cp && cp <= 'Z');

    }

    private boolean isJavaIdentifierPart(int cp) {

        return isJavaIdentifierStart(cp) || ('0' <= cp && cp <= '9');

    }

    public String[] getNameAndType(int indx) {

        return getNameAndType(indx, 0, new String[2]);

    }

    private String[] getNameAndType(int indx, int at, String[] arr) {

        CPX2 c2 = getCpoolEntry(indx);

        arr[at] = StringValue(c2.cpx1);

        arr[at + 1] = StringValue(c2.cpx2);

        return arr;

    }

    public String[] getFieldInfoName(int indx) {

        CPX2 c2 = getCpoolEntry(indx);

        String[] arr = new String[3];

        arr[0] = getClassName(c2.cpx1);

        return getNameAndType(c2.cpx2, 1, arr);

    }

    static byte[] findAttr(String n, AttrData[] attrs) {

        for (AttrData ad : attrs) {

            if (n.equals(ad.getAttrName())) {

                return ad.getData();

            }

        }

        return null;

    }

}