package buzzerproxy;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInput;
import java.io.ObjectInputStream;
import java.io.ObjectOutput;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.concurrent.Semaphore;

public class Serialization {

	private File cacheFile;

	private Semaphore semaphore = new Semaphore(1);

	/**
	 * @param filename
	 * @throws IOException
	 */
	public Serialization(String filename) throws IOException {
		if (filename == null)
			filename = "cache.ser.db";

		cacheFile = new File(filename);
		if (!cacheFile.exists()) {
			cacheFile.createNewFile();
		}
	}

	/**
	 * @param filename
	 * @param r
	 */
	public synchronized void writeCache(
			HashMap<String, ArrayList<ResultContainer>> c) {

		try {
			// Block
			semaphore.acquire();

			try {
				// use buffering
				OutputStream file = new FileOutputStream(cacheFile);
				OutputStream buffer = new BufferedOutputStream(file);
				ObjectOutput output = new ObjectOutputStream(buffer);
				try {
					output.writeObject(c);
				} finally {
					output.close();
				}
			} catch (IOException ex) {
				// Logger.getLogger(Serialization.class.getName()).log(
				// Level.SEVERE, "CacheWrite Performance Failed", ex);
			}

			// FREE
			semaphore.release();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * @param filename
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public synchronized HashMap<String, ArrayList<ResultContainer>> readCache() {

		HashMap<String, ArrayList<ResultContainer>> c = null;

		try {
			// Block
			semaphore.acquire();

			try {
				// use buffering
				InputStream file = new FileInputStream(cacheFile);
				InputStream buffer = new BufferedInputStream(file);
				ObjectInput input = new ObjectInputStream(buffer);
				try {
					// deserialize the List
					c = (HashMap<String, ArrayList<ResultContainer>>) input
							.readObject();
					// display its data
				} finally {
					input.close();
				}
			} catch (ClassNotFoundException ex) {
				// Logger.getLogger(Serialization.class.getName()).log(Level.SEVERE,
				// "CacheRead Performance Failed", ex);
			} catch (IOException ex) {
				// Logger.getLogger(Serialization.class.getName()).log(Level.SEVERE,
				// "CacheRead IO Error", ex);
			}

			// FREE
			semaphore.release();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return c;

	} // public HashMap<String, ArrayList<CacheItem>> readCache(String
		// filename) {
} // static class Serialization {