package org.freeplane.main.application;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;

import org.freeplane.core.util.FreeplaneVersion;
import org.freeplane.core.util.LogUtils;

/**
 * Handles communication with update webservice.
 * @author robert ladstaetter
 */
class HttpVersionClient {
	private static URL getUrl(final String versionUrl) {
		try {
			return new URL(versionUrl);
		}
		catch (final MalformedURLException e) {
			return null;
		}
	}

	private String history;
	private FreeplaneVersion remoteVersion;
	private boolean successful;

	public HttpVersionClient(final String versionUrl, final FreeplaneVersion currentVersion) {
		this(HttpVersionClient.getUrl(versionUrl), currentVersion);
	}

	public HttpVersionClient(final URL url, final FreeplaneVersion currentVersion) {
		remoteVersion = null;
		history = "";
		successful = false;
		BufferedReader in = null;
		try {
			in = new BufferedReader(new InputStreamReader(url.openConnection().getInputStream()));
			String line = in.readLine();
			while (line != null && !line.startsWith("=====")) {
				line = in.readLine();
			}
			while (line != null && line.startsWith("=====")) {
				line = in.readLine();
			}
			if (line == null) {
				return;
			}
			remoteVersion = FreeplaneVersion.getVersion(line);
			successful = true;
			if (remoteVersion.compareTo(currentVersion) <= 0) {
				return;
			}
			final StringBuilder historyBuffer = new StringBuilder();
			historyBuffer.append(line);
			historyBuffer.append('\n');
			for (line = in.readLine(); line != null; line = in.readLine()) {
				try {
					final FreeplaneVersion version = FreeplaneVersion.getVersion(line);
					if (version.compareTo(currentVersion) <= 0) {
						break;
					}
				}
				catch (final IllegalArgumentException e) {
				}
				historyBuffer.append(line);
				historyBuffer.append('\n');
			}
			history = historyBuffer.toString();
		}
		catch (final NullPointerException e) {
			return;
		}
		catch (final IOException e) {
			LogUtils.warn("Could not read update url - check your internet connection.");
			return;
		}
		catch (final IllegalArgumentException e) {
			LogUtils.warn("Could not read version.");
			return;
		}
		finally {
			if (in != null) {
				try {
					in.close();
				}
				catch (final IOException e) {
					LogUtils.warn("Couldn't close buffered reader.");
					return;
				}
			}
		}
	}

	public String getHistory() {
		return history;
	}

	public FreeplaneVersion getRemoteVersion() {
		return remoteVersion;
	}

	public boolean isSuccessful() {
		return successful;
	}
}