package ch.epfl.alpano.dem;

import static java.lang.Math.toRadians;

import java.awt.image.BufferedImage;
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;

import javax.imageio.ImageIO;

import ch.epfl.alpano.GeoPoint;

final class DrawElevationProfile {
  final static File HGT_FILE = new File("HGT"+File.separatorChar+"N46E006.hgt");
  final static double MAX_ELEVATION = 1_500;
  final static int LENGTH = 111_000;
  final static double AZIMUTH = toRadians(27.97);
  final static double LONGITUDE = toRadians(6.15432);
  final static double LATITUDE = toRadians(46.20562);
  final static int WIDTH = 800, HEIGHT = 100;

  public static void main(String[] as) throws Exception {
    DiscreteElevationModel dDEM =
      new HgtDiscreteElevationModel(HGT_FILE);
    ContinuousElevationModel cDEM =
      new ContinuousElevationModel(dDEM);
    GeoPoint o =
      new GeoPoint(LONGITUDE, LATITUDE);
    ElevationProfile p1 =
      new ElevationProfile(cDEM, o, AZIMUTH, (int)(LENGTH/3));
    GeoPoint gP1 = p1.positionAt((int)LENGTH/3);
    ElevationProfile p2 = 
            new ElevationProfile(cDEM, p1.positionAt((int)LENGTH/3), AZIMUTH+toRadians(6.0),2*((int)LENGTH/3));
    GeoPoint gP2 = p2.positionAt(2*((int)LENGTH/3));
    
    
    ElevationProfile p3 = new ElevationProfile (cDEM,p2.positionAt(2*((int)LENGTH/3)), AZIMUTH, LENGTH);
    
    
    ArrayList<GeoPoint> trekkingSpots = new ArrayList<GeoPoint>(Arrays.asList(o,gP1,gP2));
    ArrayList<ElevationProfile> profiles= new ArrayList<ElevationProfile>();
    for (int index = 0; index < trekkingSpots.size()-1; index++){
        GeoPoint current= trekkingSpots.get(index);
        GeoPoint next = trekkingSpots.get(index+1);
        ElevationProfile evP= new ElevationProfile(cDEM, current,current.azimuthTo(next), current.distanceTo(next));
        profiles.add(evP);
    }
    
    CompositElevationProfile p = new CompositElevationProfile(profiles);
    
    int BLACK = 0x00_00_00, WHITE = 0xFF_FF_FF;

    BufferedImage i =
      new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
    for (int x = 0; x < WIDTH; ++x) {
      double pX = x * (double) LENGTH / (WIDTH - 1);
      double pY = p.elevationAt(pX);
      int yL = (int)((pY / MAX_ELEVATION) * (HEIGHT - 1));
      for (int y = 0; y < HEIGHT; ++y) {
        int color = y < yL ? BLACK : WHITE;
        i.setRGB(x, HEIGHT - 1 - y, color);
      }
    }
    dDEM.close();

    ImageIO.write(i, "png", new File("tests/ch/epfl/alpano/dem/profile.png"));
  }
  
}