/*

 * Copyright 2007-2008 Sun Microsystems, Inc.  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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.tools.javap;

import java.util.Collection;

import java.util.List;

import com.sun.tools.classfile.AccessFlags;

import com.sun.tools.classfile.Attribute;

import com.sun.tools.classfile.Attributes;

import com.sun.tools.classfile.ClassFile;

import com.sun.tools.classfile.Code_attribute;

import com.sun.tools.classfile.ConstantPool;

import com.sun.tools.classfile.ConstantPoolException;

import com.sun.tools.classfile.Descriptor;

import com.sun.tools.classfile.DescriptorException;

import com.sun.tools.classfile.Exceptions_attribute;

import com.sun.tools.classfile.Field;

import com.sun.tools.classfile.Method;

import com.sun.tools.classfile.Signature;

import com.sun.tools.classfile.Signature_attribute;

import com.sun.tools.classfile.SourceFile_attribute;

import com.sun.tools.classfile.Type;

import static com.sun.tools.classfile.AccessFlags.*;

/*

 *  The main javap class to write the contents of a class file as text.

 *

 *  <p><b>This is NOT part of any API supported by Sun Microsystems.  If

 *  you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 */

public class ClassWriter extends BasicWriter {

    static ClassWriter instance(Context context) {

        ClassWriter instance = context.get(ClassWriter.class);

        if (instance == null)

            instance = new ClassWriter(context);

        return instance;

    }

    protected ClassWriter(Context context) {

        super(context);

        context.put(ClassWriter.class, this);

        options = Options.instance(context);

        attrWriter = AttributeWriter.instance(context);

        codeWriter = CodeWriter.instance(context);

        constantWriter = ConstantWriter.instance(context);

    }

    ClassFile getClassFile() {

        return classFile;

    }

    Method getMethod() {

        return method;

    }

    public void write(ClassFile cf) {

        classFile = cf;

        constant_pool = classFile.constant_pool;

        Attribute sfa = cf.getAttribute(Attribute.SourceFile);

        if (sfa instanceof SourceFile_attribute) {

            println("Compiled from \"" + getSourceFile((SourceFile_attribute) sfa) + "\"");

        }

        String name = getJavaName(classFile);

        AccessFlags flags = cf.access_flags;

        writeModifiers(flags.getClassModifiers());

        if (classFile.isClass())

            print("class ");

        else if (classFile.isInterface())

            print("interface ");

        print(name);

        Signature_attribute sigAttr = getSignature(cf.attributes);

        if (sigAttr == null) {

            // use info from class file header

            if (classFile.isClass() && classFile.super_class != 0 ) {

                String sn = getJavaSuperclassName(cf);

                print(" extends ");

                print(sn);

            }

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

                print(i == 0 ? (classFile.isClass() ? " implements " : " extends ") : ",");

                print(getJavaInterfaceName(classFile, i));

            }

        } else {

            try {

                Type t = sigAttr.getParsedSignature().getType(constant_pool);

                // The signature parser cannot disambiguate between a

                // FieldType and a ClassSignatureType that only contains a superclass type.

                if (t instanceof Type.ClassSigType)

                    print(t);

                else {

                    print(" extends ");

                    print(t);

                }

            } catch (ConstantPoolException e) {

                print(report(e));

            }

        }

        if (options.verbose) {

            println();

            attrWriter.write(cf, cf.attributes, constant_pool);

            println("  minor version: " + cf.minor_version);

            println("  major version: " + cf.major_version);

            if (!options.compat)

              writeList("  flags: ", flags.getClassFlags(), NEWLINE);

            constantWriter.writeConstantPool();

            println();

        } else {

            if (!options.compat)

                print(" ");

        }

        println("{");

        writeFields();

        writeMethods();

        println("}");

        println();

    }

    void writeFields() {

        for (Field f: classFile.fields) {

            writeField(f);

        }

    }

    void writeField(Field f) {

        if (!options.checkAccess(f.access_flags))

            return;

        if (!(options.showLineAndLocalVariableTables

                || options.showDisassembled

                || options.verbose

                || options.showInternalSignatures

                || options.showAllAttrs)) {

            print("    ");

        }

        AccessFlags flags = f.access_flags;

        writeModifiers(flags.getFieldModifiers());

        Signature_attribute sigAttr = getSignature(f.attributes);

        if (sigAttr == null)

            print(getFieldType(f.descriptor));

        else {

            try {

                Type t = sigAttr.getParsedSignature().getType(constant_pool);

                print(t);

            } catch (ConstantPoolException e) {

                // report error?

                // fall back on non-generic descriptor

                print(getFieldType(f.descriptor));

            }

        }

        print(" ");

        print(getFieldName(f));

        print(";");

        println();

        if (options.showInternalSignatures)

            println("  Signature: " + getValue(f.descriptor));

        if (options.verbose && !options.compat)

            writeList("  flags: ", flags.getFieldFlags(), NEWLINE);

        if (options.showAllAttrs) {

            for (Attribute attr: f.attributes)

                attrWriter.write(f, attr, constant_pool);

            println();

        }

        if (options.showDisassembled || options.showLineAndLocalVariableTables)

            println();

    }

    void writeMethods() {

        for (Method m: classFile.methods)

            writeMethod(m);

    }

    void writeMethod(Method m) {

        if (!options.checkAccess(m.access_flags))

            return;

        method = m;

        if (!(options.showLineAndLocalVariableTables

                || options.showDisassembled

                || options.verbose

                || options.showInternalSignatures

                || options.showAllAttrs)) {

            print("    ");

        }

        AccessFlags flags = m.access_flags;

        Descriptor d;

        Type.MethodType methodType;

        List<? extends Type> methodExceptions;

        Signature_attribute sigAttr = getSignature(m.attributes);

        if (sigAttr == null) {

            d = m.descriptor;

            methodType = null;

            methodExceptions = null;

        } else {

            Signature methodSig = sigAttr.getParsedSignature();

            d = methodSig;

            try {

                methodType = (Type.MethodType) methodSig.getType(constant_pool);

                methodExceptions = methodType.throwsTypes;

                if (methodExceptions != null && methodExceptions.size() == 0)

                    methodExceptions = null;

            } catch (ConstantPoolException e) {

                // report error?

                // fall back on standard descriptor

                methodType = null;

                methodExceptions = null;

            }

        }

        writeModifiers(flags.getMethodModifiers());

        if (methodType != null) {

            writeListIfNotEmpty("<", methodType.typeArgTypes, "> ");

        }

        if (getName(m).equals("<init>")) {

            print(getJavaName(classFile));

            print(getParameterTypes(d, flags));

        } else if (getName(m).equals("<clinit>")) {

            print("{}");

        } else {

            print(getReturnType(d));

            print(" ");

            print(getName(m));

            print(getParameterTypes(d, flags));

        }

        Attribute e_attr = m.attributes.get(Attribute.Exceptions);

        if (e_attr != null) { // if there are generic exceptions, there must be erased exceptions

            if (e_attr instanceof Exceptions_attribute) {

                Exceptions_attribute exceptions = (Exceptions_attribute) e_attr;

                if (options.compat) { // Bug XXXXXXX whitespace

                    if (!(options.showLineAndLocalVariableTables

                            || options.showDisassembled

                            || options.verbose

                            || options.showInternalSignatures

                            || options.showAllAttrs)) {

                        print("    ");

                    }

                    print("  ");

                }

                print(" throws ");

                if (methodExceptions != null) { // use generic list if available

                    writeList("", methodExceptions, "");

                } else {

                    for (int i = 0; i < exceptions.number_of_exceptions; i++) {

                        if (i > 0)

                            print(", ");

                        print(getJavaException(exceptions, i));

                    }

                }

            } else {

                report("Unexpected or invalid value for Exceptions attribute");

            }

        }

        print(";");

        println();

        if (options.showInternalSignatures)

            println("  Signature: " + getValue(m.descriptor));

        if (options.verbose && !options.compat)

            writeList("  flags: ", flags.getMethodFlags(), NEWLINE);

        Code_attribute code = null;

        Attribute c_attr = m.attributes.get(Attribute.Code);

        if (c_attr != null) {

            if (c_attr instanceof Code_attribute)

                code = (Code_attribute) c_attr;

            else

                report("Unexpected or invalid value for Code attribute");

        }

        if (options.showDisassembled && !options.showAllAttrs) {

            if (code != null) {

                println("  Code:");

                codeWriter.writeInstrs(code);

                codeWriter.writeExceptionTable(code);

            }

            println();

        }

        if (options.showLineAndLocalVariableTables) {

            if (code != null)

                attrWriter.write(code, code.attributes.get(Attribute.LineNumberTable), constant_pool);

            println();

            if (code != null)

                attrWriter.write(code, code.attributes.get(Attribute.LocalVariableTable), constant_pool);

            println();

            println();

        }

        if (options.showAllAttrs) {

            Attribute[] attrs = m.attributes.attrs;

            for (Attribute attr: attrs)

                attrWriter.write(m, attr, constant_pool);

//            // the following condition is to mimic old javap

//            if (!(attrs.length > 0 &&

//                    attrs[attrs.length - 1] instanceof Exceptions_attribute))

            println();

        }

    }

    void writeModifiers(Collection<String> items) {

        for (Object item: items) {

            print(item);

            print(" ");

        }

    }

    void writeList(String prefix, Collection<?> items, String suffix) {

        print(prefix);

        String sep = "";

        for (Object item: items) {

            print(sep);

            print(item);

            sep = ", ";

        }

        print(suffix);

    }

    void writeListIfNotEmpty(String prefix, List<?> items, String suffix) {

        if (items != null && items.size() > 0)

            writeList(prefix, items, suffix);

    }

    Signature_attribute getSignature(Attributes attributes) {

        if (options.compat) // javap does not recognize recent attributes

            return null;

        return (Signature_attribute) attributes.get(Attribute.Signature);

    }

    String adjustVarargs(AccessFlags flags, String params) {

        if (flags.is(ACC_VARARGS) && !options.compat) {

            int i = params.lastIndexOf("[]");

            if (i > 0)

                return params.substring(0, i) + "..." + params.substring(i+2);

        }

        return params;

    }

    String getJavaName(ClassFile cf) {

        try {

            return getJavaName(cf.getName());

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getJavaSuperclassName(ClassFile cf) {

        try {

            return getJavaName(cf.getSuperclassName());

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getJavaInterfaceName(ClassFile cf, int index) {

        try {

            return getJavaName(cf.getInterfaceName(index));

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getFieldType(Descriptor d) {

        try {

            return d.getFieldType(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        } catch (DescriptorException e) {

            return report(e);

        }

    }

    String getReturnType(Descriptor d) {

        try {

            return d.getReturnType(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        } catch (DescriptorException e) {

            return report(e);

        }

    }

    String getParameterTypes(Descriptor d, AccessFlags flags) {

        try {

            return adjustVarargs(flags, d.getParameterTypes(constant_pool));

        } catch (ConstantPoolException e) {

            return report(e);

        } catch (DescriptorException e) {

            return report(e);

        }

    }

    String getJavaException(Exceptions_attribute attr, int index) {

        try {

            return getJavaName(attr.getException(index, constant_pool));

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getValue(Descriptor d) {

        try {

            return d.getValue(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getFieldName(Field f) {

        try {

            return f.getName(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    String getName(Method m) {

        try {

            return m.getName(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }

    static String getJavaName(String name) {

        return name.replace('/', '.');

    }

    String getSourceFile(SourceFile_attribute attr) {

        try {

            return attr.getSourceFile(constant_pool);

        } catch (ConstantPoolException e) {

            return report(e);

        }

    }