/*
 * Copyright (C) 2013 RoboVM AB
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/gpl-2.0.html>.
 */
package org.robovm.llvm;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import org.robovm.llvm.binding.IntOut;
import org.robovm.llvm.binding.LLVM;
import org.robovm.llvm.binding.LongArray;
import org.robovm.llvm.binding.LongArrayOut;
import org.robovm.llvm.binding.MemoryBufferRefOut;
import org.robovm.llvm.binding.ObjectFileRef;
import org.robovm.llvm.binding.StringOut;
import org.robovm.llvm.binding.SymbolIteratorRef;

/**
 * 
 */
public class ObjectFile implements AutoCloseable {
    private final File file;
    private ObjectFileRef ref;

    private ObjectFile(File file, ObjectFileRef objectFileRef) {
        this.file = file;
        this.ref = objectFileRef;
    }
    
    protected final void checkDisposed() {
        if (ref == null) {
            throw new LlvmException("Already disposed");
        }
    }
    
    protected ObjectFileRef getRef() {
        checkDisposed();
        return ref;
    }
    
    public List<Symbol> getSymbols() {
        List<Symbol> result = new ArrayList<>();
        SymbolIteratorRef it = LLVM.GetSymbols(getRef());
        while (!LLVM.IsSymbolIteratorAtEnd(getRef(), it)) {
            String name = LLVM.GetSymbolName(it);
            long address = LLVM.GetSymbolAddress(it);
            long size = LLVM.GetSymbolSize(it);
            result.add(new Symbol(name, address, size));
            LLVM.MoveToNextSymbol(it);
        }
        LLVM.DisposeSymbolIterator(it);
        return result;
    }
    
    public SectionIterator getSectionIterator() {
        return new SectionIterator(this, LLVM.GetSections(getRef()));
    }

    public List<LineInfo> getLineInfos(Symbol symbol) {
        List<LineInfo> result = new ArrayList<>();
        IntOut sizeOut = new IntOut();
        LongArrayOut out = new LongArrayOut();
        LLVM.GetLineInfoForAddressRange(getRef(), symbol.getAddress(), symbol.getSize(), sizeOut, out);
        int size = sizeOut.getValue();
        if (size > 0) {
            LongArray values = out.getValue();
            for (int i = 0; i < size; i++) {
                long address = values.get(i * 2);
                long lineNumber = values.get(i * 2 + 1);
                result.add(new LineInfo(address, (int) lineNumber));
            }
            values.delete();
        }
        out.delete();
        return result;
    }
    
    public synchronized void dispose() {
        LLVM.DisposeObjectFile(getRef());
        ref = null;
    }

    @Override
    public void close() {
        dispose();
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((file == null) ? 0 : file.hashCode());
        result = prime * result + ((ref == null) ? 0 : ref.hashCode());
        return result;
    }

    @Override
    public String toString() {
        return "ObjectFile [file=" + file + "]";
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        ObjectFile other = (ObjectFile) obj;
        if (file == null) {
            if (other.file != null) {
                return false;
            }
        } else if (!file.equals(other.file)) {
            return false;
        }
        if (ref == null) {
            if (other.ref != null) {
                return false;
            }
        } else if (!ref.equals(other.ref)) {
            return false;
        }
        return true;
    }

    public static ObjectFile load(File file) {
        MemoryBufferRefOut memBufOut = new MemoryBufferRefOut();
        StringOut errorMsgOut = new StringOut();
        LLVM.CreateMemoryBufferWithContentsOfFile(file.getAbsolutePath(), memBufOut, errorMsgOut);
        if (memBufOut.getValue() == null) {
            throw new LlvmException("Failed to create memory buffer from " + file.getAbsolutePath() 
                    + (errorMsgOut.getValue() != null ? ":" + errorMsgOut.getValue() : ""));
        }
        ObjectFileRef ref = LLVM.CreateObjectFile(memBufOut.getValue());
        if (ref == null) {
            throw new LlvmException("Failed to create memory buffer from " + file.getAbsolutePath());
        }
        return new ObjectFile(file, ref);
    }
}