package pt.ist.fenixframework.plugins.luceneIndexing;

import java.util.ArrayList;
import java.util.List;

import pt.ist.fenixframework.plugins.luceneIndexing.domain.DomainIndexFile;
import pt.utl.ist.fenix.tools.util.ByteArray;

public class RAMIndex implements IndexFile {

    static final int BUFFER_SIZE = 1024;

    private List<ByteArray> buffers;
    private long length;
    private long lastModified = System.currentTimeMillis();
    private DomainIndexFile domainIndexFile;
    private String name;

    public RAMIndex() {
        this.buffers = new ArrayList<ByteArray>();
    }

    public RAMIndex(DomainIndexFile domainIndexFile) {
        this();
        this.domainIndexFile = domainIndexFile;
        this.name = domainIndexFile.getName();
        this.length = domainIndexFile.getLength();
        Long lastModified2 = domainIndexFile.getLastModified();
        this.lastModified = lastModified2 != null ? lastModified2 : System.currentTimeMillis();
        this.buffers = this.domainIndexFile.split(BUFFER_SIZE);
    }

    private void dumpBuffersToDomainIndex() {
        byte[] totalArray = new byte[BUFFER_SIZE * buffers.size()];
        int offset = 0;
        for (ByteArray array : buffers) {
            byte[] bytes = array.getBytes();
            if (bytes.length > BUFFER_SIZE) {
                System.out.println("buffer length is greater than buffer size...WTF!");
            }
            System.arraycopy(bytes, 0, totalArray, offset, Math.min(bytes.length, BUFFER_SIZE));
            offset += BUFFER_SIZE;
        }
        this.domainIndexFile.setIndexContent(totalArray);
    }

    @Override
    public synchronized Long getLength() {
        return length;
    }

    public synchronized void setLength(long length) {
        this.length = length;
    }

    @Override
    public synchronized Long getLastModified() {
        return lastModified;
    }

    public synchronized void setLastModified(long lastModified) {
        this.lastModified = lastModified;
    }

    public final synchronized ByteArray addBuffer(int size) {
        ByteArray buffer = new ByteArray(new byte[size]);
        buffers.add(buffer);
        return buffer;
    }

    final synchronized ByteArray getBuffer(int index) {
        return buffers.get(index);
    }

    final synchronized int numBuffers() {
        return buffers.size();
    }

    @Override
    public String getName() {
        return name;
    }

    @Override
    public void setName(String name) {
        this.name = name;
    }

    @Override
    public void setLastModified(Long time) {
        this.lastModified = time;
    }

    @Override
    public void setLength(Long length) {
        this.length = length;
    }

    @Override
    public RAMIndex getNonPersistentIndex() {
        return this;
    }

    @Override
    public DomainIndexFile getPersistentIndex() {
        return this.domainIndexFile;
    }

    @Override
    public boolean isPersisted() {
        return false;
    }

    public void persist() {
        dumpBuffersToDomainIndex();
        this.domainIndexFile.setName(getName());
        this.domainIndexFile.setLastModified(getLastModified());
        this.domainIndexFile.setLength(getLength());
    }
}