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();

	// Average all the vector normals
	for (int i = 0; i < vertices; i++) {
	  vertList[i].averageNormals();
        }

        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);
	    float nx = (vertList[v1].z - vertList[v0].z) * (vertList[v2].y - vertList[v1].y)
	      - (vertList[v1].y - vertList[v0].y) * (vertList[v2].z - vertList[v1].z);
	    float ny = (vertList[v1].x - vertList[v0].x) * (vertList[v2].z - vertList[v1].z)
	      - (vertList[v1].z - vertList[v0].z) * (vertList[v2].x - vertList[v1].x);
	    float nz = (vertList[v1].y - vertList[v0].y) * (vertList[v2].x - vertList[v1].x)
	      - (vertList[v1].x - vertList[v0].x) * (vertList[v2].y - vertList[v1].y);
	    if (faceTris == 0) {
	      // the normal could be computed here instead if all
	      // facets are planar... I'll just play it safe
	      vertList[v0].addNormal(nx, ny, nz);
	      vertList[v1].addNormal(nx, ny, nz);
	    }
	    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]);
	    vertList[v2].addNormal(nx, ny, nz);
	    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();
    }

}