package tim.prune.function.srtm;

import java.io.File;
import java.io.FileReader;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.HttpURLConnection;
import java.util.HashMap;

import tim.prune.GpsPrune;
import tim.prune.I18nManager;

public class SrtmViewfinderSource extends SrtmSource {
	/** URL prefix for all tiles */
	private static final String URL_PREFIX = "http://viewfinderpanoramas.org/";
	private HashMap<SrtmTile, String> _tile_lookup = null;

	public SrtmViewfinderSource()
	{
	}

	public String getNameKey()
	{
		return "function.downloadsrtm." + getName();
	}

	public String getName()
	{
		return "SRTM_Viewfinder";
	}

	protected String getSourceExtension()
	{
		return ".zip";
	}

	/**
	 * Read the dat file and get the contents
	 * @return byte array containing file contents
	 */
	private void populateLookup()
		throws SrtmSourceException
	{
		BufferedReader in = null;
		try
		{
			// in = SrtmViewfinderSource.class.getResourceAsStream("viewfinder/tiles.db");
			_tile_lookup = new HashMap<SrtmTile, String>();
			in = new BufferedReader(new InputStreamReader(SrtmViewfinderSource.class.getResourceAsStream("/tim/prune/function/srtm/viewfinder/tiles.dat")));
			String line;
			while ((line = in.readLine()) != null)
			{
				String[] parts = line.split(" ");
				SrtmTile tile = new SrtmTile(Integer.parseInt(parts[0]), Integer.parseInt(parts[1]));
				_tile_lookup.put(tile, parts[2]);
			}
		}
		catch (Exception e) {
			throw new SrtmSourceException("Exception trying to read tiles.db: " + e);
		}
		finally
		{
			try {
				in.close();
			}
			catch (Exception e) {} // ignore
		}
	}

	/**
	 * Get the Url for the given tile
	 * @param inTile Tile to get
	 * @return URL
	 */
	private URL buildUrl(SrtmTile inTile)
		throws SrtmSourceException
	{
		if (_tile_lookup == null)
		{
			populateLookup();
		}
		System.out.println(_tile_lookup.get(inTile));
		String path = _tile_lookup.get(inTile);
		if (path == null)
		{
			int key = inTile.hashCode();
			System.out.println("inTile hashcode " + key);
			for (HashMap.Entry<SrtmTile, String> e : _tile_lookup.entrySet())
			{
				if (e.getKey().getLatitude() == 51)
				{
					System.out.println(e.getKey().getTileName() + " - " + e.getKey().hashCode() + " -> " + e.getValue());
				}
			}
			throw new SrtmSourceException("tile not in database "+inTile.getTileName());
		}
		try
		{
			return new URL(URL_PREFIX + path + getSourceExtension());
		}
		catch (MalformedURLException e)
		{
			e.printStackTrace();
			throw new SrtmSourceException(e.getMessage());
		}
	}

	public boolean isReadyToUse()
	{
		return true;
	}

	public boolean downloadTile(SrtmTile inTile)
		throws SrtmSourceException
	{
		int redirects = 5;
		URL tileUrl = buildUrl(inTile);
		File outputFile = getCacheFileName(inTile);
		System.out.println("Download: Need to download: " + tileUrl);

		try
		{
			HttpURLConnection conn = (HttpURLConnection) tileUrl.openConnection();

			// Define streams
			FileOutputStream outStream = null;
			InputStream inStream = null;

			conn.setRequestProperty("User-Agent", "GpsPrune v" + GpsPrune.VERSION_NUMBER);

			int status = conn.getResponseCode();
			if (status == 200)
			{
				inStream = conn.getInputStream();
			}
			else if (status == 404)
			{
				throw new SrtmSourceException("Tile not found: "+conn.getURL());
			}
			else
			{
				throw new SrtmSourceException("Invalid response from server: " +status+conn.getContent());
			}

			outStream = new FileOutputStream(outputFile);

			int c;
			while ((c = inStream.read()) != -1)
			{
				outStream.write(c);
			}
			// Make sure streams are closed
			try {inStream.close();} catch (Exception e) {}
			try {outStream.close();} catch (Exception e) {}
			return true;
		}
		catch (IOException e)
		{
			throw new SrtmSourceException("Error while downloading tile "+inTile.getTileName()+": "+e.getMessage());
		}
	}

	public int getRowSize(SrtmTile inTile)
	{
		return 1201;
	}
}