import java.applet.*;
import java.awt.*;
import java.io.*;
import java.net.*;
import Vertex3D;
import Point3D;
import Triangle;
import Matrix3D;
import Light;
import Surface;
import ZRaster;

public class Pipeline extends Applet {
  final static int CHUNKSIZE = 100;
  ZRaster raster;
  Image screen;
  Vertex3D vertList[];
  Vertex3D worldList[];
  Vertex3D canonicalList[];
  int vertices;
  Triangle triList[];
  int triangles;
  Matrix3D view;
  Matrix3D model;
  Matrix3D project;
  boolean cull = true;

  Light lightList[];
  int lights;
  Surface surfaceList[];
  int surfaces;

  Point3D eye, lookat, up;
  Point3D initEye, initLookat;
  float fov;

  public void init( )
    {
      raster = new ZRaster(size().width, size().height);

      // initialize viewing parameters to default
      // values in case they are not defined by the
      // input file
      eye = new Point3D(0, 0, -10);
      lookat = new Point3D(0, 0, 0);
      up = new Point3D(0, 1, 0);
      fov = 30;

      vertList = new Vertex3D[CHUNKSIZE];
      vertices = 0;
      triList = new Triangle[CHUNKSIZE];
      triangles = 0;
      lightList = new Light[CHUNKSIZE];
      lights = 0;
      surfaceList = new Surface[CHUNKSIZE];
      surfaces = 0;

      String filename = getParameter("datafile");
      showStatus("Reading "+filename);
      InputStream is = null;
      try {
	is = new URL(getDocumentBase(), filename).openStream();
	ReadInput(is);
	is.close();
      } catch (IOException e) {
	showStatus("Error reading "+filename);
      }
        
      if (getParameter("cull") != null)
	if (getParameter("cull").equals("false"))
	  cull = false;
            
      canonicalList = new Vertex3D[vertList.length];
      worldList = new Vertex3D[vertList.length];
      for (int i = 0; i < vertices; i++) {
	canonicalList[i] = new Vertex3D();
	worldList[i] = new Vertex3D();
      }
      initEye = new Point3D(eye);
      initLookat = new Point3D(lookat);
        
      project = new Matrix3D(raster);
      view = new Matrix3D();
      float t = (float) Math.sin(Math.PI*(fov/2)/180);
      float s = (t*size().height)/size().width;
      view.perspective(-t, t, -s, s, -1, -200);
      view.lookAt(eye.x, eye.y, eye.z, lookat.x, lookat.y, lookat.z, up.x, up.y, up.z);
      model = new Matrix3D();
      DrawObject();
    }

  private double getNumber(StreamTokenizer st) throws IOException
    {
      if (st.nextToken() != StreamTokenizer.TT_NUMBER) {
	System.err.println("ERROR: line "+st.lineno()+": expected number");
	throw new IOException(st.toString());
      }
      return st.nval;
    }

  private void growList()
    {
      Triangle newList[] = new Triangle[triList.length+CHUNKSIZE];
      System.arraycopy(triList, 0, newList, 0, triList.length);
      triList = newList;
    }

  public void ReadInput(InputStream is) throws IOException
    {
      StreamTokenizer st = new StreamTokenizer(is);
      st.commentChar('#');
    scan: while (true) {
      switch (st.nextToken()) {
      default:
	break scan;
      case StreamTokenizer.TT_WORD:
	if (st.sval.equals("v")) {
	  float x = (float) getNumber(st);
	  float y = (float) getNumber(st);
	  float z = (float) getNumber(st);
	  if (vertices == vertList.length) {
	    Vertex3D newList[] = new Vertex3D[vertList.length+CHUNKSIZE];
	    System.arraycopy(vertList, 0, newList, 0, vertList.length);
	    vertList = newList;
	  }
	  vertList[vertices++] = new Vertex3D(x, y, z);
	} else if (st.sval.equals("f")) {
	  int faceTris = 0;
	  int v0 = (int) getNumber(st);
	  int v1 = (int) getNumber(st);
	  while (st.nextToken() == StreamTokenizer.TT_NUMBER) {
	    st.pushBack();
	    int v2 = (int) getNumber(st);
	    if (v2 == v0) continue;
	    if (triangles == triList.length) growList();
	    triList[triangles] = new Triangle(v0, v1, v2);
	    if (surfaces == 0) {
	      surfaceList[surfaces] = new Surface(0.5f, 0.5f, 0.5f, 1.0f, 1.0f, 1.0f, 5.0f);
	      surfaces += 1;
	    }
	    triList[triangles].setSurface(surfaceList[surfaces-1]);
	    v1 = v2;
	    faceTris += 1;
	    triangles += 1;
	  }
	  st.pushBack();
	} else if (st.sval.equals("eye")) {
	  eye.x = (float) getNumber(st);
	  eye.y = (float) getNumber(st);
	  eye.z = (float) getNumber(st);
	} else if (st.sval.equals("look")) {
	  lookat.x = (float) getNumber(st);
	  lookat.y = (float) getNumber(st);
	  lookat.z = (float) getNumber(st);
	} else if (st.sval.equals("up")) {
	  up.x = (float) getNumber(st);
	  up.y = (float) getNumber(st);
	  up.z = (float) getNumber(st);
	} else if (st.sval.equals("fov")) {
	  fov = (float) getNumber(st);
	} else if (st.sval.equals("la")) {             // ambient light source
	  float r = (float) getNumber(st);
	  float g = (float) getNumber(st);
	  float b = (float) getNumber(st);
	  lightList[lights] = new Light(Light.AMBIENT, 0, 0, 0, r, g, b);
	  lights += 1;
	} else if (st.sval.equals("ld")) {             // directional light source
	  float r = (float) getNumber(st);
	  float g = (float) getNumber(st);
	  float b = (float) getNumber(st);
	  float x = (float) getNumber(st);
	  float y = (float) getNumber(st);
	  float z = (float) getNumber(st);
	  lightList[lights] = new Light(Light.DIRECTIONAL, x, y, z, r, g, b);
	  lights += 1;
	} else if (st.sval.equals("lp")) {             // point light source
	  float r = (float) getNumber(st);
	  float g = (float) getNumber(st);
	  float b = (float) getNumber(st);
	  float x = (float) getNumber(st);
	  float y = (float) getNumber(st);
	  float z = (float) getNumber(st);
	  lightList[lights] = new Light(Light.POINT, x, y, z, r, g, b);
	  lights += 1;
	} else if (st.sval.equals("surf")) {
	  float r = (float) getNumber(st);
	  float g = (float) getNumber(st);
	  float b = (float) getNumber(st);
	  float ka = (float) getNumber(st);
	  float kd = (float) getNumber(st);
	  float ks = (float) getNumber(st);
	  float ns = (float) getNumber(st);
	  surfaceList[surfaces] = new Surface(r, g, b, ka, kd, ks, ns);
	  surfaces += 1;
	} else {
	  System.err.println("ERROR: line "+st.lineno()+": unexpected token :"+st.sval);
	  break scan;
	}
	break;
      }
      if (triangles % 100 == 0) showStatus("triangles = "+triangles);
    }
      is.close();
      if (st.ttype != StreamTokenizer.TT_EOF) {
	throw new IOException(st.toString());
      }
    }

  public void paint(Graphics g)
    {
      g.drawImage(screen, 0, 0, this);
    }

  public void update(Graphics g)
    {
      paint(g);
    }

  int oldx, oldy;

  public boolean mouseDown(Event e, int x, int y)
    {
      if (e.metaDown()) {
	System.out.println("Reset view matrix");
	eye.copy(initEye);
	lookat.copy(initLookat);
	view.loadIdentity();
	float t = (float) Math.sin(Math.PI*(fov/2)/180);
	float s = (t*size().height)/size().width;
	view.perspective(-t, t, -s, s, -1, -200);
	view.lookAt(eye.x, eye.y, eye.z, lookat.x, lookat.y, lookat.z, up.x, up.y, up.z);
	DrawObject();
      }
      oldx = x;
      oldy = y;
      return true;
    }

  public boolean mouseDrag(Event e, int x, int y)
    {
      if (e.metaDown()) {
	System.out.println("Resetting view matrix");
      } else {
	float ax = lookat.x - eye.x;
	float ay = lookat.y - eye.y;
	float az = lookat.z - eye.z;
	float t = (float) (getSize().width / (2*Math.tan(((fov * Math.PI)/180)/2)));
	Matrix3D r = new Matrix3D( );
	t = (float) (Math.atan((double)(x - oldx)/t));
	r.rotate(up.x, up.y, up.z, t);
	eye.x = eye.x + ax*(oldy - y)/size().height;
	eye.y = eye.y + ay*(oldy - y)/size().height;
	eye.z = eye.z + az*(oldy - y)/size().height;
	lookat.x = r.get(0,0)*ax + r.get(1,0)*ay + r.get(2,0)*az;
	lookat.y = r.get(0,1)*ax + r.get(1,1)*ay + r.get(2,1)*az;
	lookat.z = r.get(0,2)*ax + r.get(1,2)*ay + r.get(2,2)*az;
	lookat.x += eye.x;
	lookat.y += eye.y;
	lookat.z += eye.z;
	t = (float) Math.sin(Math.PI*(fov/2)/180);
	float s = (t*size().height)/size().width;
	view.loadIdentity();
	view.perspective(-t, t, -s, s, -1, -200);
	view.lookAt(eye.x, eye.y, eye.z, lookat.x, lookat.y, lookat.z, up.x, up.y, up.z);
	oldx = x;
	oldy = y;
	DrawObject();
      }
      return true;
    }

  void DrawObject()
    {
      long time = System.currentTimeMillis();
      showStatus("Drawing "+triangles+" triangles ...");
        
      /*
	... cull and illuminate in world space ...
      */
      model.transform(vertList, worldList, vertices);
      triList[0].setVertexList(worldList);
      for (int i = 0; i < triangles; i++) {
	triList[i].Illuminate(lightList, lights, eye, cull);
      }
        
      /*
	.... clip in canonical eye coordinates ...
      */
      view.transform(worldList, canonicalList, vertices);
      triList[0].setVertexList(canonicalList);
      raster.fill(Color.white);
      raster.resetz();
      for (int i = 0; i < triangles; i++) {
	// check if trivially rejected
	if (triList[i].isVisible()) {
	  triList[i].ClipAndDraw(raster, project);
	}
      }
      time = System.currentTimeMillis() - time;
      showStatus("Time = "+time+" ms");
      screen = raster.toImage( );
      repaint();
    }

}