package com.osmand;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Point;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.awt.image.RenderedImage;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.net.URLConnection;
import java.net.UnknownHostException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Stack;

import javax.imageio.IIOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.osmand.DataExtraction.ExitListener;
import com.osmand.data.DataTileManager;
import com.osmand.osm.LatLon;
import com.osmand.osm.MapUtils;

public class MapPanel extends JPanel {
	
	private static final long serialVersionUID = 1L;
	
	private static final Log log = LogFactory.getLog(MapPanel.class);


	public static void main(String[] args) throws IOException {
		JFrame frame = new JFrame("Tree of choose");
	    try {
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		} catch (Exception e) {
			e.printStackTrace();
		}
		
		
	    frame.addWindowListener(new ExitListener());
	    Container content = frame.getContentPane();
	    
	    MapPanel panel = new MapPanel(new File(DefaultLauncherConstants.pathToDirWithTiles));
	    
	    content.add(panel, BorderLayout.CENTER);
	    
	    frame.setSize(512, 512);
	    frame.setVisible(true);

	}

	// name of source map 
	private String map = "Mapnik";
	
	// tile size of map 
	private final int tileSize = 256;
		
	// file name with tiles
	private final File fileWithTiles;

	// special points to draw
	private DataTileManager<LatLon> points;
	
	// zoom levle
	private int zoom = 15;
	
	// degree measurements (-180, 180)
	// долгота
	private double longitude = 27.56;
	// широта
	// degree measurements (90, -90)
	private double latitude = 53.9;
	
	private List<IMapLocationListener> listeners = new ArrayList<IMapLocationListener>();
	
	// cached data to draw image
	private Image[][] images;
	private int xStartingImage = 0;
	private int yStartingImage = 0;
	private List<Point> pointsToDraw = new ArrayList<Point>();
	
	private AsyncLoadTileThread autoThread = new AsyncLoadTileThread();
	Map<String, Image> cache = new HashMap<String, Image>();
	
	
	
	public MapPanel(File fileWithTiles) {
		this.fileWithTiles = fileWithTiles;
		autoThread.start();
		initUI();
	}

	
	public double getXTile(){
		return MapUtils.getTileNumberX(zoom, longitude);
	}
	
	public double getYTile(){
		return MapUtils.getTileNumberY(zoom, latitude);
	}
	

	@Override
	protected void paintComponent(Graphics g) {
		
		if (images != null) {
			for (int i = 0; i < images.length; i++) {
				for (int j = 0; j < images[i].length; j++) {
					if(images[i][j] == null){
					    int div = 4;
					    int tileDiv = tileSize / div;
					    for(int k1 = 0; k1 < div; k1++){
					    	for(int k2 = 0; k2 < div; k2++){
					    		if ((k1 + k2) % 2 == 0) {
									g.setColor(Color.gray);
								} else {
									g.setColor(Color.white);
								}
					    		g.fillRect(i * tileSize+xStartingImage + k1*tileDiv,
					    				j * tileSize + yStartingImage + k2*tileDiv, tileDiv, tileDiv);
						    	
						    }
					    }
					} else {
						g.drawImage(images[i][j], i * tileSize+xStartingImage, j * tileSize + yStartingImage, this);
					}
				}
			}
		}
		g.setColor(Color.black);
		// draw user points
		for(Point p : pointsToDraw){
			g.drawOval(p.x, p.y, 3, 3);
			g.fillOval(p.x, p.y, 3, 3);
		}
	
		String s = MessageFormat.format("Lat : {0}, lon : {1}, zoom : {2}",latitude, longitude, zoom);
		g.drawString(s, 5, 20);
		
		
		g.fillOval(getWidth()/2 - 2, getHeight()/2 -2, 4, 4);
		g.drawOval(getWidth()/2 - 2, getHeight()/2 -2, 4, 4);
		g.drawOval(getWidth()/2 - 5, getHeight()/2 -5, 10, 10);
	}
	
	public String getFile(int zoom, int x, int y){
		return map +"/"+zoom+"/"+(x) +"/"+y+".png";
	}
	
	 
	public Image getImageFor(int x, int y) throws IOException{
		String file = getFile(zoom, x, y);
		if(!cache.containsKey(file)){
//			ZipEntry en = fileWithTiles.getEntry(file);
			File en = new File(fileWithTiles, file);
			if(cache.size() > 1000){
				ArrayList<String> list = new ArrayList<String>(cache.keySet());
				for(int i=0; i<list.size(); i+=2){
					cache.remove(list.get(i));
				}
			}
//			if(en != null){
			if(en.exists()){
//				cache.put(file, ImageIO.read(fileWithTiles.getInputStream(en)));
				long time = System.currentTimeMillis();
				cache.put(file, ImageIO.read(en));
				System.out.println("Loaded " + (System.currentTimeMillis() - time));
			} else {
				autoThread.requestTileToLoad(zoom, x, y);
			}
		}
		
		return cache.get(file);
	}
	
	public void loadImage(int zoom, int x, int y){
		try {
			Image img = null;
			File en = new File(fileWithTiles, getFile(zoom, x, y));
			URL url = new URL("http://tile.openstreetmap.org/" + zoom + "/" + x + "/" + y + ".png");
			en.getParentFile().mkdirs();
			try {
				ImageIO.setUseCache(true);
				javax.imageio.ImageIO.setCacheDirectory(en.getParentFile());
			} catch (Exception e) {
				log.warn("cannot set ImageIO cache-directory to " + en.getParent(), e);
			}
			try {
				URLConnection connection = url.openConnection();
				connection.setRequestProperty("User-Agent", "osmand TilePainter/0.1");
				img = javax.imageio.ImageIO.read(connection.getInputStream());
			} catch (UnknownHostException e) {
				log.info("UnknownHostException, cannot download tile " + url.toExternalForm());
			} catch (IIOException e) {
				if (e.getCause() != null && e.getCause() instanceof UnknownHostException) {
					log.info("UnknownHostException, cannot download tile " + url.toExternalForm(), e);
				} else {
					log.warn("cannot download tile " + url.toExternalForm(), e);
				}
			}
			cache.put(getFile(zoom, x, y), img);
			if (img != null) {
				try {
					ImageIO.write((RenderedImage) img, "png", en);
				} catch (IOException e) {
					log.warn("cannot save img to " + en.getAbsolutePath(), e);
				}
			}
		} catch (IOException e) {
			log.warn("cannot download pre-rendered tile [" + e.getClass().getSimpleName() + "]", e);
		}
	}
	
	
	public class AsyncLoadTileThread extends Thread {
		Stack<TileIndex> tilesToLoad = new Stack<TileIndex>();
		private class TileIndex {
			int zoom;
			int x;
			int y;
		}
		
		public AsyncLoadTileThread() {
			super("AsyncLoadingTiles");
		}
		
		@Override
		public void run() {
			try {
				while (true) {
					synchronized (this) {
						wait();
					}
					while (!tilesToLoad.isEmpty()) {
						TileIndex p = tilesToLoad.pop();
						if (cache.get(getFile(p.zoom, p.x, p.y)) == null) {
							loadImage(p.zoom, p.x, p.y);
							// TODO dead cycle (causes cancelAllPreviousTile)
							prepareImage();
						}
					}
				}
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
		
		public void cancelAllPreviousTile(){
			tilesToLoad.clear();
		}
		
		public void requestTileToLoad(int zoom, int x, int y){
			synchronized (this) {
				TileIndex ind = new TileIndex();
				ind.zoom = zoom;
				ind.x = x;
				ind.y = y;
				tilesToLoad.add(ind);
				notify();
			}
			
		}
		
	}
	
	
	
	// TODO async loading images (show busy cursor while it is loaded)
	public void prepareImage(){
		try {
			
			if (images != null) {
				for (int i = 0; i < images.length; i++) {
					for (int j = 0; j < images[i].length; j++) {
						// dispose 
					}
				}
			}
			
			double xTileLeft = getXTile() - getSize().width / (2d * tileSize);
			double xTileRight = getXTile() + getSize().width / (2d * tileSize);
			double yTileUp = getYTile() - getSize().height / (2d * tileSize);
			double yTileDown = getYTile() + getSize().height / (2d * tileSize);
		    
			xStartingImage = -(int) ((xTileLeft - Math.floor(xTileLeft)) * tileSize);
			yStartingImage = -(int) ((yTileUp - Math.floor(yTileUp)) * tileSize);

			autoThread.cancelAllPreviousTile();
			int tileXCount = ((int) xTileRight - (int) xTileLeft + 1);
			int tileYCount = ((int) yTileDown - (int) yTileUp + 1);
			images = new BufferedImage[tileXCount][tileYCount];
			for (int i = 0; i < images.length; i++) {
				for (int j = 0; j < images[i].length; j++) {
					images[i][j] = getImageFor((int) xTileLeft + i, (int) yTileUp + j);
				}
			}
			
			if (points != null) {
				double latDown = MapUtils.getLatitudeFromTile(zoom, yTileDown);
				double longDown = MapUtils.getLongitudeFromTile(zoom, xTileRight);
				double latUp = MapUtils.getLatitudeFromTile(zoom, yTileUp);
				double longUp = MapUtils.getLongitudeFromTile(zoom, xTileLeft);
				List<LatLon> objects = points.getObjects(latUp, longUp, latDown, longDown);
				pointsToDraw.clear();
				for (LatLon n : objects) {
					int pixX = MapUtils.getPixelShiftX(zoom, n.getLongitude(), this.longitude, tileSize) + getWidth() / 2;
					int pixY = MapUtils.getPixelShiftY(zoom, n.getLatitude(), this.latitude, tileSize) + getHeight() / 2;
					if (pixX >= 0 && pixY >= 0) {
						pointsToDraw.add(new Point(pixX, pixY));
					}
				}
			}
			
			repaint();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	
	
	private void initUI() {
		setFocusable(true);
		addComponentListener(new ComponentAdapter(){
			public void componentResized(ComponentEvent e) {
				prepareImage();
			}
		});
		MapMouseAdapter mouse = new MapMouseAdapter();
		addMouseListener(mouse);
		addMouseMotionListener(mouse);
	}
	
	
	public void setZoom(int zoom){
		this.zoom = zoom;
		prepareImage();
	}

	public void setLatLon(double latitude, double longitude){
		this.latitude = latitude;
		this.longitude = longitude;
		prepareImage();
		fireMapLocationListeners();
	}
	
	public double getLatitude() {
		return latitude;
	}
	
	public double getLongitude() {
		return longitude;
	}
	
	public int getZoom() {
		return zoom;
	}
	
	public String getMap(){
		return map;
	}
	
	public void setMapName(String map){
		this.map = map;
		prepareImage();
	}
	
	public void addMapLocationListener(IMapLocationListener l){
		listeners.add(l);
	}
	
	public void removeMapLocationListener(IMapLocationListener l){
		listeners.remove(l);
	}
	
	protected void fireMapLocationListeners(){
		for(IMapLocationListener l : listeners){
			l.locationChanged(latitude, longitude, null);
		}
	}
	
	
	@Override
	protected void processKeyEvent(KeyEvent e) {
		boolean processed = false;
		if (e.getID() == KeyEvent.KEY_RELEASED) {
			if (e.getKeyCode() == 37) {
				// LEFT button
				longitude = MapUtils.getLongitudeFromTile(zoom, getXTile()-0.5); 
				processed = true;
			} else if (e.getKeyCode() == 39) {
				// RIGHT button
				longitude = MapUtils.getLongitudeFromTile(zoom, getXTile()+0.5);
				processed = true;
			} else if (e.getKeyCode() == 38) {
				// UP button
				latitude = MapUtils.getLatitudeFromTile(zoom, getYTile()-0.5);
				processed = true;
			} else if (e.getKeyCode() == 40) {
				// DOWN button
				latitude = MapUtils.getLatitudeFromTile(zoom, getYTile()+0.5);
				processed = true;
			}
		}
		if(e.getID() == KeyEvent.KEY_TYPED){
			if(e.getKeyChar() == '+'){
				if(zoom < 18){
					zoom ++;
					processed = true;
				}
			} else if(e.getKeyChar() == '-'){
				if(zoom > 1){
					zoom --;
					processed = true;
				}
			}
		}
		
		if(processed){
			e.consume();
			prepareImage();
			fireMapLocationListeners();
		}
		super.processKeyEvent(e);
	}
	
	public DataTileManager<LatLon> getPoints() {
		return points;
	}
	
	public void setPoints(DataTileManager<LatLon> points) {
		this.points = points;
	}
	
	public class MapMouseAdapter extends MouseAdapter {
		private Point startDragging = null;
		
		@Override
		public void mouseClicked(MouseEvent e) {
			if(e.getButton() == MouseEvent.BUTTON1){
				requestFocus();
			}
		}
		
		public void dragTo(Point p){
			double dx = (startDragging.x - (double)p.x)/tileSize; 
			double dy = (startDragging.y - (double)p.y)/tileSize;
			double lat = MapUtils.getLatitudeFromTile(zoom, getYTile() + dy);
			double lon = MapUtils.getLongitudeFromTile(zoom, getXTile() + dx);
			setLatLon(lat, lon);
		}
		
		@Override
		public void mouseDragged(MouseEvent e) {
			if(startDragging != null){
				if(Math.abs(e.getPoint().x - startDragging.x) +  Math.abs(e.getPoint().y - startDragging.y) >= 8){
					dragTo(e.getPoint());
					startDragging = e.getPoint();
				}
			}
		}
		
		@Override
		public void mousePressed(MouseEvent e) {
			if(e.getButton() == MouseEvent.BUTTON3){
				if(startDragging == null){
					startDragging  = e.getPoint();
				}
			}
		}
		@Override
		public void mouseReleased(MouseEvent e) {
			if(e.getButton() == MouseEvent.BUTTON3){
				if(startDragging != null){
					dragTo(e.getPoint());
					fireMapLocationListeners();
					startDragging = null;
				}
			}
			super.mouseReleased(e);
		}

	}

}