/*

 * Copyright (c) 2007, 2014, 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 com.sun.tools.javap;

import java.net.URI;

import java.text.DateFormat;

import java.util.Collection;

import java.util.Date;

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.ConstantValue_attribute;

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 com.sun.tools.classfile.Type.ArrayType;

import com.sun.tools.classfile.Type.ClassSigType;

import com.sun.tools.classfile.Type.ClassType;

import com.sun.tools.classfile.Type.MethodType;

import com.sun.tools.classfile.Type.SimpleType;

import com.sun.tools.classfile.Type.TypeParamType;

import com.sun.tools.classfile.Type.WildcardType;

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 supported API.

 *  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);

    }

    void setDigest(String name, byte[] digest) {

        this.digestName = name;

        this.digest = digest;

    }

    void setFile(URI uri) {

        this.uri = uri;

    }

    void setFileSize(int size) {

        this.size = size;

    }

    void setLastModified(long lastModified) {

        this.lastModified = lastModified;

    }

    protected ClassFile getClassFile() {

        return classFile;

    }

    protected void setClassFile(ClassFile cf) {

        classFile = cf;

        constant_pool = classFile.constant_pool;

    }

    protected Method getMethod() {

        return method;

    }

    protected void setMethod(Method m) {

        method = m;

    }

    public void write(ClassFile cf) {

        setClassFile(cf);

        if (options.sysInfo || options.verbose) {

            if (uri != null) {

                if (uri.getScheme().equals("file"))

                    println("Classfile " + uri.getPath());

                else

                    println("Classfile " + uri);

            }

            indent(+1);

            if (lastModified != -1) {

                Date lm = new Date(lastModified);

                DateFormat df = DateFormat.getDateInstance();

                if (size > 0) {

                    println("Last modified " + df.format(lm) + "; size " + size + " bytes");

                } else {

                    println("Last modified " + df.format(lm));

                }

            } else if (size > 0) {

                println("Size " + size + " bytes");

            }

            if (digestName != null && digest != null) {

                StringBuilder sb = new StringBuilder();

                for (byte b: digest)

                    sb.append(String.format("%02x", b));

                println(digestName + " checksum " + sb);

            }

        }

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

        if (sfa instanceof SourceFile_attribute) {

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

        }

        if (options.sysInfo || options.verbose) {

            indent(-1);

        }

        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);

                if (!sn.equals("java.lang.Object")) {

                    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);

                JavaTypePrinter p = new JavaTypePrinter(classFile.isInterface());

                // The signature parser cannot disambiguate between a

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

                if (t instanceof Type.ClassSigType) {

                    print(p.print(t));

                } else if (options.verbose || !t.isObject()) {

                    print(" extends ");

                    print(p.print(t));

                }

            } catch (ConstantPoolException e) {

                print(report(e));

            }

        }

        if (options.verbose) {

            println();

            indent(+1);

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

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

            writeList("flags: ", flags.getClassFlags(), "\n");

            indent(-1);

            constantWriter.writeConstantPool();

        } else {

            print(" ");

        }

        println("{");

        indent(+1);

        writeFields();

        writeMethods();

        indent(-1);

        println("}");

        if (options.verbose) {

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

        }

    }

    // where

        class JavaTypePrinter implements Type.Visitor<StringBuilder,StringBuilder> {

            boolean isInterface;

            JavaTypePrinter(boolean isInterface) {

                this.isInterface = isInterface;

            }

            String print(Type t) {

                return t.accept(this, new StringBuilder()).toString();

            }

            String printTypeArgs(List<? extends TypeParamType> typeParamTypes) {

                StringBuilder builder = new StringBuilder();

                appendIfNotEmpty(builder, "<", typeParamTypes, "> ");

                return builder.toString();

            }

            public StringBuilder visitSimpleType(SimpleType type, StringBuilder sb) {

                sb.append(getJavaName(type.name));

                return sb;

            }

            public StringBuilder visitArrayType(ArrayType type, StringBuilder sb) {

                append(sb, type.elemType);

                sb.append("[]");

                return sb;

            }

            public StringBuilder visitMethodType(MethodType type, StringBuilder sb) {

                appendIfNotEmpty(sb, "<", type.typeParamTypes, "> ");

                append(sb, type.returnType);

                append(sb, " (", type.paramTypes, ")");

                appendIfNotEmpty(sb, " throws ", type.throwsTypes, "");

                return sb;

            }

            public StringBuilder visitClassSigType(ClassSigType type, StringBuilder sb) {

                appendIfNotEmpty(sb, "<", type.typeParamTypes, ">");

                if (isInterface) {

                    appendIfNotEmpty(sb, " extends ", type.superinterfaceTypes, "");

                } else {

                    if (type.superclassType != null

                            && (options.verbose || !type.superclassType.isObject())) {

                        sb.append(" extends ");

                        append(sb, type.superclassType);

                    }

                    appendIfNotEmpty(sb, " implements ", type.superinterfaceTypes, "");

                }

                return sb;

            }

            public StringBuilder visitClassType(ClassType type, StringBuilder sb) {

                if (type.outerType != null) {

                    append(sb, type.outerType);

                    sb.append(".");

                }

                sb.append(getJavaName(type.name));

                appendIfNotEmpty(sb, "<", type.typeArgs, ">");

                return sb;

            }

            public StringBuilder visitTypeParamType(TypeParamType type, StringBuilder sb) {

                sb.append(type.name);

                String sep = " extends ";

                if (type.classBound != null

                        && (options.verbose || !type.classBound.isObject())) {

                    sb.append(sep);

                    append(sb, type.classBound);

                    sep = " & ";

                }

                if (type.interfaceBounds != null) {

                    for (Type bound: type.interfaceBounds) {

                        sb.append(sep);

                        append(sb, bound);

                        sep = " & ";

                    }

                }

                return sb;

            }

            public StringBuilder visitWildcardType(WildcardType type, StringBuilder sb) {

                switch (type.kind) {

                    case UNBOUNDED:

                        sb.append("?");

                        break;

                    case EXTENDS:

                        sb.append("? extends ");

                        append(sb, type.boundType);

                        break;

                    case SUPER:

                        sb.append("? super ");

                        append(sb, type.boundType);

                        break;

                    default:

                        throw new AssertionError();

                }

                return sb;

            }

            private void append(StringBuilder sb, Type t) {

                t.accept(this, sb);

            }

            private void append(StringBuilder sb, String prefix, List<? extends Type> list, String suffix) {

                sb.append(prefix);

                String sep = "";

                for (Type t: list) {

                    sb.append(sep);

                    append(sb, t);

                    sep = ", ";

                }

                sb.append(suffix);

            }

            private void appendIfNotEmpty(StringBuilder sb, String prefix, List<? extends Type> list, String suffix) {

                if (!isEmpty(list))

                    append(sb, prefix, list, suffix);

            }

            private boolean isEmpty(List<? extends Type> list) {

                return (list == null || list.isEmpty());

            }

        }

    protected void writeFields() {

        for (Field f: classFile.fields) {

            writeField(f);

        }

    }

    protected void writeField(Field f) {

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

            return;

        AccessFlags flags = f.access_flags;

        writeModifiers(flags.getFieldModifiers());

        Signature_attribute sigAttr = getSignature(f.attributes);

        if (sigAttr == null)

            print(getJavaFieldType(f.descriptor));

        else {

            try {

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

                print(getJavaName(t.toString()));

            } catch (ConstantPoolException e) {

                // report error?

                // fall back on non-generic descriptor

                print(getJavaFieldType(f.descriptor));

            }

        }

        print(" ");

        print(getFieldName(f));

        if (options.showConstants) {

            Attribute a = f.attributes.get(Attribute.ConstantValue);

            if (a instanceof ConstantValue_attribute) {

                print(" = ");

                ConstantValue_attribute cv = (ConstantValue_attribute) a;

                print(getConstantValue(f.descriptor, cv.constantvalue_index));

            }

        }

        print(";");

        println();

        indent(+1);

        boolean showBlank = false;

        if (options.showDescriptors)

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

        if (options.verbose)

            writeList("flags: ", flags.getFieldFlags(), "\n");

        if (options.showAllAttrs) {

            for (Attribute attr: f.attributes)

                attrWriter.write(f, attr, constant_pool);

            showBlank = true;

        }

        indent(-1);

        if (showBlank || options.showDisassembled || options.showLineAndLocalVariableTables)

            println();

    }

    protected void writeMethods() {

        for (Method m: classFile.methods)

            writeMethod(m);

        setPendingNewline(false);

    }

    protected void writeMethod(Method m) {

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

            return;

        method = m;

        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.isEmpty())

                    methodExceptions = null;

            } catch (ConstantPoolException e) {

                // report error?

                // fall back on standard descriptor

                methodType = null;

                methodExceptions = null;

            }

        }

        writeModifiers(flags.getMethodModifiers());

        if (methodType != null) {

            print(new JavaTypePrinter(false).printTypeArgs(methodType.typeParamTypes));

        }

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

            print(getJavaName(classFile));

            print(getJavaParameterTypes(d, flags));

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

            print("{}");

        } else {

            print(getJavaReturnType(d));

            print(" ");

            print(getName(m));

            print(getJavaParameterTypes(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;

                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");

            }

        }

        println(";");

        indent(+1);

        if (options.showDescriptors) {

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

        }

        if (options.verbose) {

            writeList("flags: ", flags.getMethodFlags(), "\n");

        }

        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");

        }