/*

 * Copyright (c) 2009, 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 com.sun.tools.classfile.Code_attribute;

import com.sun.tools.classfile.Code_attribute.Exception_data;

import com.sun.tools.classfile.Instruction;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.ListIterator;

import java.util.Map;

/**

 * Annotate instructions with details about try blocks.

 *

 *  <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 TryBlockWriter extends InstructionDetailWriter {

    public enum NoteKind {

        START("try") {

            public boolean match(Exception_data entry, int pc) {

                return (pc == entry.start_pc);

            }

        },

        END("end try") {

            public boolean match(Exception_data entry, int pc) {

                return (pc == entry.end_pc);

            }

        },

        HANDLER("catch") {

            public boolean match(Exception_data entry, int pc) {

                return (pc == entry.handler_pc);

            }

        };

        NoteKind(String text) {

            this.text = text;

        }

        public abstract boolean match(Exception_data entry, int pc);

        public final String text;

    static TryBlockWriter instance(Context context) {

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

        if (instance == null)

            instance = new TryBlockWriter(context);

        return instance;

    }

    protected TryBlockWriter(Context context) {

        super(context);

        context.put(TryBlockWriter.class, this);

        constantWriter = ConstantWriter.instance(context);

    }

    public void reset(Code_attribute attr) {

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

            Exception_data entry = attr.exception_table[i];

            indexMap.put(entry, i);

            put(entry.start_pc, entry);

            put(entry.end_pc, entry);

            put(entry.handler_pc, entry);

        }

    }

    public void writeDetails(Instruction instr) {

        writeTrys(instr, NoteKind.END);

        writeTrys(instr, NoteKind.START);

        writeTrys(instr, NoteKind.HANDLER);

    }

    public void writeTrys(Instruction instr, NoteKind kind) {

        String indent = space(2); // get from Options?

        int pc = instr.getPC();

        List<Exception_data> entries = pcMap.get(pc);

        if (entries != null) {

            for (ListIterator<Exception_data> iter =

                    entries.listIterator(kind == NoteKind.END ? entries.size() : 0);

                    kind == NoteKind.END ? iter.hasPrevious() : iter.hasNext() ; ) {

                Exception_data entry =

                        kind == NoteKind.END ? iter.previous() : iter.next();

                if (kind.match(entry, pc)) {

                    print(indent);

                    print(kind.text);

                    print("[");

                    print(indexMap.get(entry));

                    print("] ");

                    if (entry.catch_type == 0)

                        print("finally");

                    else {

                        print("#" + entry.catch_type);

                        print(" // ");

                        constantWriter.write(entry.catch_type);

                    }

                    println();

                }

            }

        }

    }

    private void put(int pc, Exception_data entry) {

        List<Exception_data> list = pcMap.get(pc);

        if (list == null) {

            pcMap.put(pc, list);

        }

        if (!list.contains(entry))

            list.add(entry);

    }

    private Map<Integer, List<Exception_data>> pcMap;

    private Map<Exception_data, Integer> indexMap;

    private ConstantWriter constantWriter;

}