/*

 * Copyright (c) 2007, 2013, 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.util.ArrayList;

import java.util.List;

import com.sun.tools.classfile.AccessFlags;

import com.sun.tools.classfile.Code_attribute;

import com.sun.tools.classfile.ConstantPool;

import com.sun.tools.classfile.ConstantPoolException;

import com.sun.tools.classfile.DescriptorException;

import com.sun.tools.classfile.Instruction;

import com.sun.tools.classfile.Instruction.TypeKind;

import com.sun.tools.classfile.Method;

/*

 *  Write the contents of a Code attribute.

 *

 *  <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 CodeWriter extends BasicWriter {

    public static CodeWriter instance(Context context) {

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

        if (instance == null)

            instance = new CodeWriter(context);

        return instance;

    }

    protected CodeWriter(Context context) {

        super(context);

        context.put(CodeWriter.class, this);

        attrWriter = AttributeWriter.instance(context);

        classWriter = ClassWriter.instance(context);

        constantWriter = ConstantWriter.instance(context);

        sourceWriter = SourceWriter.instance(context);

        tryBlockWriter = TryBlockWriter.instance(context);

        stackMapWriter = StackMapWriter.instance(context);

        localVariableTableWriter = LocalVariableTableWriter.instance(context);

        localVariableTypeTableWriter = LocalVariableTypeTableWriter.instance(context);

        typeAnnotationWriter = TypeAnnotationWriter.instance(context);

        options = Options.instance(context);

    }

    void write(Code_attribute attr, ConstantPool constant_pool) {

        println("Code:");

        indent(+1);

        writeVerboseHeader(attr, constant_pool);

        writeInstrs(attr);

        writeExceptionTable(attr);

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

        indent(-1);

    }

    public void writeVerboseHeader(Code_attribute attr, ConstantPool constant_pool) {

        Method method = classWriter.getMethod();

        String argCount;

        try {

            int n = method.descriptor.getParameterCount(constant_pool);

            if (!method.access_flags.is(AccessFlags.ACC_STATIC))

                ++n;  // for 'this'

            argCount = Integer.toString(n);

        } catch (ConstantPoolException e) {

            argCount = report(e);

        } catch (DescriptorException e) {

            argCount = report(e);

        }

        println("stack=" + attr.max_stack +

                ", locals=" + attr.max_locals +

                ", args_size=" + argCount);

    }

    public void writeInstrs(Code_attribute attr) {

        List<InstructionDetailWriter> detailWriters = getDetailWriters(attr);

        for (Instruction instr: attr.getInstructions()) {

            try {

                for (InstructionDetailWriter w: detailWriters)

                    w.writeDetails(instr);

                writeInstr(instr);

            } catch (ArrayIndexOutOfBoundsException e) {

                println(report("error at or after byte " + instr.getPC()));

                break;

            }

        }

        for (InstructionDetailWriter w: detailWriters)

            w.flush();

    }

    public void writeInstr(Instruction instr) {

        print(String.format("%4d: %-13s ", instr.getPC(), instr.getMnemonic()));

        // compute the number of indentations for the body of multi-line instructions

        // This is 6 (the width of "%4d: "), divided by the width of each indentation level,

        // and rounded up to the next integer.

        int indentWidth = options.indentWidth;

        int indent = (6 + indentWidth - 1) / indentWidth;

        instr.accept(instructionPrinter, indent);

        println();

    }

    // where

    Instruction.KindVisitor<Void,Integer> instructionPrinter =

            new Instruction.KindVisitor<Void,Integer>() {

        public Void visitNoOperands(Instruction instr, Integer indent) {

            return null;

        }

        public Void visitArrayType(Instruction instr, TypeKind kind, Integer indent) {

            print(" " + kind.name);

            return null;

        }

        public Void visitBranch(Instruction instr, int offset, Integer indent) {

            print((instr.getPC() + offset));

            return null;

        }

        public Void visitConstantPoolRef(Instruction instr, int index, Integer indent) {

            print("#" + index);

            tab();

            print("// ");

            printConstant(index);

            return null;

        }

        public Void visitConstantPoolRefAndValue(Instruction instr, int index, int value, Integer indent) {

            print("#" + index + ",  " + value);

            tab();

            print("// ");

            printConstant(index);

            return null;

        }

        public Void visitLocal(Instruction instr, int index, Integer indent) {

            print(index);

            return null;

        }

        public Void visitLocalAndValue(Instruction instr, int index, int value, Integer indent) {

            print(index + ", " + value);

            return null;

        }

        public Void visitLookupSwitch(Instruction instr,

                int default_, int npairs, int[] matches, int[] offsets, Integer indent) {

            int pc = instr.getPC();

            print("{ // " + npairs);

            indent(indent);

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

                print(String.format("%n%12d: %d", matches[i], (pc + offsets[i])));

            }

            print("\n     default: " + (pc + default_) + "\n}");

            indent(-indent);

            return null;

        }

        public Void visitTableSwitch(Instruction instr,

                int default_, int low, int high, int[] offsets, Integer indent) {

            int pc = instr.getPC();

            print("{ // " + low + " to " + high);

            indent(indent);

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

                print(String.format("%n%12d: %d", (low + i), (pc + offsets[i])));

            }

            print("\n     default: " + (pc + default_) + "\n}");

            indent(-indent);

            return null;

        }

        public Void visitValue(Instruction instr, int value, Integer indent) {

            print(value);

            return null;

        }

        public Void visitUnknown(Instruction instr, Integer indent) {

            return null;

        }

    };

    public void writeExceptionTable(Code_attribute attr) {

        if (attr.exception_table_length > 0) {

            println("Exception table:");

            indent(+1);

            println(" from    to  target type");

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

                Code_attribute.Exception_data handler = attr.exception_table[i];

                print(String.format(" %5d %5d %5d",

                        handler.start_pc, handler.end_pc, handler.handler_pc));

                print("   ");

                int catch_type = handler.catch_type;

                if (catch_type == 0) {

                    println("any");

                } else {

                    print("Class ");

                    println(constantWriter.stringValue(catch_type));

                }

            }

            indent(-1);

        }

    }

    private void printConstant(int index) {

        constantWriter.write(index);

    }

    private List<InstructionDetailWriter> getDetailWriters(Code_attribute attr) {

        List<InstructionDetailWriter> detailWriters = new ArrayList<>();

        if (options.details.contains(InstructionDetailWriter.Kind.SOURCE)) {

            sourceWriter.reset(classWriter.getClassFile(), attr);

            if (sourceWriter.hasSource())

                detailWriters.add(sourceWriter);

            else

                println("(Source code not available)");

        }

        if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VARS)) {

            localVariableTableWriter.reset(attr);

            detailWriters.add(localVariableTableWriter);

        }

        if (options.details.contains(InstructionDetailWriter.Kind.LOCAL_VAR_TYPES)) {

            localVariableTypeTableWriter.reset(attr);

            detailWriters.add(localVariableTypeTableWriter);

        }

        if (options.details.contains(InstructionDetailWriter.Kind.STACKMAPS)) {

            stackMapWriter.reset(attr);

            stackMapWriter.writeInitialDetails();

            detailWriters.add(stackMapWriter);

        }

        if (options.details.contains(InstructionDetailWriter.Kind.TRY_BLOCKS)) {

            tryBlockWriter.reset(attr);

            detailWriters.add(tryBlockWriter);

        }

        if (options.details.contains(InstructionDetailWriter.Kind.TYPE_ANNOS)) {

            typeAnnotationWriter.reset(attr);

            detailWriters.add(typeAnnotationWriter);

        }

        return detailWriters;

    }

    private AttributeWriter attrWriter;

    private ClassWriter classWriter;

    private ConstantWriter constantWriter;

    private LocalVariableTableWriter localVariableTableWriter;

    private LocalVariableTypeTableWriter localVariableTypeTableWriter;

    private TypeAnnotationWriter typeAnnotationWriter;

    private SourceWriter sourceWriter;

    private StackMapWriter stackMapWriter;

    private TryBlockWriter tryBlockWriter;

    private Options options;

}