/*
 * 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.
 
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.
/**
 * 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) {
        indexMap = new HashMap<>();
        pcMap = new HashMap<>();
        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) {
            list = new ArrayList<>();
            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;
}