// Wendy Chien
// Recitation F11-12
// Project 4

// This is the code supplied in class.  

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( )
  {
    int i;
    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 (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();
    triList[0].setVertexList(vertList);
    for (i=0;i<triangles;i++) {
      triList[i].initNormal();
    }
    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, 0, vertices);
    triList[0].setVertexList(worldList);
    for (int i = 0; i < triangles; i++) {
      triList[i].setNormal(model.normalTransform(triList[i].normal));
      triList[i].Illuminate(lightList, lights, eye, cull);
    }
    
    /*
      .... clip in canonical eye coordinates ...
      */
    view.transform(worldList, canonicalList, 0, 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();
  }
  
}