/*
 * DisplayListModel3D.java
 *
 * Created on February 27, 2008, 11:05 PM
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package net.java.joglutils.model.examples;

import net.java.joglutils.model.*;
import com.sun.opengl.util.texture.Texture;
import com.sun.opengl.util.texture.TextureCoords;
import com.sun.opengl.util.texture.TextureIO;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import java.util.HashMap;
import javax.imageio.ImageIO;
import javax.media.opengl.GL;
import javax.media.opengl.GLAutoDrawable;
import net.java.joglutils.model.ResourceRetriever;
import net.java.joglutils.model.geometry.Bounds;
import net.java.joglutils.model.geometry.Material;
import net.java.joglutils.model.geometry.Mesh;
import net.java.joglutils.model.geometry.Model;
import net.java.joglutils.model.geometry.Vec4;
import net.java.joglutils.model.iModel3DRenderer;

/**
 *
 * @author RodgersGB
 * 
 * modifications made by Brian Wood and Z-Knight
 */
public class DisplayListRenderer implements iModel3DRenderer {
    private static DisplayListRenderer instance = new DisplayListRenderer();
    private DisplayListCache listCache = new DisplayListCache();
    private HashMap<Integer, Texture> texture;
    private int modelBoundsList = -1;
    private int objectBoundsList = 1;
    private boolean isDebugging = true;
    
    /** Creates a new instance of DisplayListModel3D */
    public DisplayListRenderer() {
    }
    
    public static DisplayListRenderer getInstance() {
        return instance;
    }

    public void debug(boolean value) {
        this.isDebugging = value;
    }
    
    public void render(Object context, Model model)
    {
        GL gl = null;
        
        if (context instanceof GL)
            gl = (GL) context;
        
        else if (context instanceof GLAutoDrawable)
            gl = ((GLAutoDrawable) context).getGL();
        
        if (gl == null) {
            return;
        }
        
        if (model == null) {
            return;
        }
        
        int displayList = listCache.get(model);
        
        if(displayList < 0) {
            displayList = initialize(gl, model);
            if (this.isDebugging)
                System.out.println("Initialized the display list for model: " + model.getSource());
        }
        
        // save some current state variables
        boolean isTextureEnabled = gl.glIsEnabled(GL.GL_TEXTURE_2D);
        boolean isLightingEnabled = gl.glIsEnabled(GL.GL_LIGHTING);        
        boolean isMaterialEnabled = gl.glIsEnabled(GL.GL_COLOR_MATERIAL);
        
        // check texture
        if (model.isUsingTexture()) { gl.glEnable(GL.GL_TEXTURE_2D); }
        else { gl.glDisable(GL.GL_TEXTURE_2D); }
        
        // check wireframe
        if (model.isRenderingAsWireframe()) { gl.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_LINE); }
        else { gl.glPolygonMode(GL.GL_FRONT_AND_BACK, GL.GL_FILL); }
        
        // check lighting
        if (model.isUsingLighting()) { gl.glEnable(GL.GL_LIGHTING); }
        else { gl.glDisable(GL.GL_LIGHTING); }
        
        gl.glDisable(GL.GL_COLOR_MATERIAL);
        
        gl.glPushMatrix();
        
        // check for unit size model
        if (model.isUnitizeSize()) {
            float scale = 1.0f/model.getBounds().getRadius();
            gl.glScalef(scale, scale, scale);
        }
        
        if (model.isCentered()) {
            Vec4 center = model.getCenterPoint();
            gl.glTranslatef(-center.x, -center.y, -center.z);
        }
        
        if (model.isRenderModel())
            gl.glCallList(displayList);
        
        // Disabled lighting for drawing the boundary lines so they are all white (or whatever I chose)
        gl.glDisable(GL.GL_LIGHTING);
        if (model.isRenderModelBounds())
            gl.glCallList(modelBoundsList);
        if (model.isRenderObjectBounds())
            gl.glCallList(objectBoundsList);
        
        gl.glPopMatrix();

        // Reset the flags back for lighting and texture
        if (isTextureEnabled) {
            gl.glEnable(GL.GL_TEXTURE_2D);
        } else {
            gl.glDisable(GL.GL_TEXTURE_2D);
        }

        if (isLightingEnabled) {
            gl.glEnable(GL.GL_LIGHTING);
        } else {
            gl.glDisable(GL.GL_LIGHTING);
        }

        if (isMaterialEnabled) {
            gl.glEnable(GL.GL_COLOR_MATERIAL);
        } else {
            gl.glDisable(GL.GL_COLOR_MATERIAL);
        }
    }
    
    /**
     * Load the model and associated materials, etc
     * 
     * @param gl
     * @param file
     * @return
     */
    private int initialize(GL gl, Model model) 
    {
        if (this.isDebugging)
            System.out.println("Initialize Model: " + model.getSource());
        
        int numMaterials = model.getNumberOfMaterials();
        
        if (this.isDebugging && numMaterials > 0) {
            System.out.println("\n    Loading " + numMaterials + " Materials:");            
        }
        
        String file = model.getSource();
        texture = new HashMap<Integer, Texture>();
        for (int i=0; i<numMaterials; i++) {
            // TODO:DELETE THIS OLD LINE loadTexture(materials.get(i).strFile, i);
            // TODO:DELETE THIS OLD LINE materials.get(i).texureId = i;
            
            String subFileName = "";
            
            // If this is read from a jar file, then try to find the path relative to the model
            int index = file.lastIndexOf('/');
            if (index != -1) {
                subFileName = file.substring(0,index+1);
            } else {
                // Else, the file path of the model was not from a jar file, so check maybe it
                // was from a local file and get that path.
                index = file.lastIndexOf('\\');
                
                if (index != -1) {
                     subFileName = file.substring(0,index+1);
                }
            }
             
            if (model.getMaterial(i).strFile != null) {
                if (this.isDebugging)
                    System.out.print("        Material:  " + subFileName + model.getMaterial(i).strFile);                
                
                URL result;
                try {
                    result = ResourceRetriever.getResourceAsUrl(subFileName + model.getMaterial(i).strFile);
                } catch(IOException e) {
                    if (this.isDebugging)
                        System.err.println(" ... failed");
                    continue;
                }

                if (result != null && !result.getPath().endsWith("/") && !result.getPath().endsWith("\\")) {
                    loadTexture(result, i);
                    model.getMaterial(i).textureId = i;
                    if (this.isDebugging)
                        System.out.println(" ... done. Texture ID: " + i);
                } else if (this.isDebugging) {
                    System.out.println(" ... failed (no result for material)");
                }   
            }            
        }
        
        if (this.isDebugging && numMaterials > 0) {
            System.out.println("    Load Materials: Done");            
        }
        
        if (this.isDebugging)
            System.out.println("\n    Generate Lists:");
        int compiledList = listCache.generateList(model, gl, 3);
        
        if (this.isDebugging)
            System.out.println("        Model List");         
        gl.glNewList(compiledList, GL.GL_COMPILE);
            genList(gl, model);
        gl.glEndList();
        
        modelBoundsList = compiledList + 1;

        if (this.isDebugging)
            System.out.println("        Boundary List");                 
        gl.glNewList(modelBoundsList, GL.GL_COMPILE);
            genModelBoundsList(gl, model);
        gl.glEndList();
        
        objectBoundsList = compiledList + 2;
        
        if (this.isDebugging)
            System.out.println("        Object Boundary List");                         
        gl.glNewList(objectBoundsList, GL.GL_COMPILE);
            genObjectBoundsList(gl, model);
        gl.glEndList();
        
        if (this.isDebugging)
        {
            System.out.println("    Generate Lists: Done");
            System.out.println("Load Model: Done");
        }
        
        return compiledList;
    }
    
    /**
     * Load a texture given by the specified URL and assign it to the texture
     * id that is passed in.
     * 
     * @param url
     * @param id
     */
    private void loadTexture(URL url, int id) {
        if ( url != null ) {
            BufferedImage bufferedImage = null;

            try {
                bufferedImage = ImageIO.read(url);
            } catch (Exception e) {
                System.err.println(" ... FAILED loading texture with exception: "+e.getMessage());
                return;
            }
            
            texture.put(id, TextureIO.newTexture(bufferedImage, true));
        }
    }
    
    /**
     * Generate the model display list
     * 
     * @param gl
     */
    private void genList(GL gl, Model model) {
        TextureCoords coords;
        
        for (int i=0; i<model.getNumberOfMeshes(); i++) {
            Mesh tempObj = model.getMesh(i);
            
            if (tempObj.numOfFaces == 0) {
                System.err.println("Mesh: " +tempObj.name + " has no faces");
                continue;
            }
     
            if(tempObj.hasTexture && texture.get(tempObj.materialID) != null) {
                Texture t = texture.get(tempObj.materialID);
                
                // switch to texture mode and push a new matrix on the stack
                gl.glMatrixMode(GL.GL_TEXTURE);
                gl.glPushMatrix();

                // check to see if the texture needs flipping
                if (t.getMustFlipVertically()) {
                    gl.glScaled(1, -1, 1);
                    gl.glTranslated(0, -1, 0);
                }

                // switch to modelview matrix and push a new matrix on the stack
                gl.glMatrixMode(GL.GL_MODELVIEW);
                gl.glPushMatrix();

                // This is required to repeat textures...because some are not and so only
                // part of the model gets filled in....Might be a way to check if this is
                // required per object but I'm not sure...would need to research this.
                gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, GL.GL_REPEAT);
                gl.glTexParameteri(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, GL.GL_REPEAT);

                // enable, bind and get texture coordinates
                t.enable();
                t.bind();
                coords = t.getImageTexCoords();
            }
            
            for (int j=0; j<tempObj.numOfFaces; j++) {

                // If the object has a texture, then do nothing till later...else
                // apply the material property to it.
                if(tempObj.hasTexture) { 
                    // nothing

                // Has no texture but has a material instead and this material is
                // the FACES material, and not the OBJECTS material ID as being used
                // incorrectly below...by specification, the materialID is associated
                // with a FACE and not an OBJECT
                } else {
                    if (tempObj.faces[j].materialID < model.getNumberOfMaterials()) {
                        float[] rgba = new float[4];
                        
                        Material material = model.getMaterial(tempObj.faces[j].materialID);
                        gl.glMaterialfv(GL.GL_FRONT, GL.GL_DIFFUSE, material.diffuseColor.getRGBComponents(rgba), 0);
                        gl.glMaterialfv(GL.GL_FRONT, GL.GL_AMBIENT, material.ambientColor.getRGBComponents(rgba), 0);
                        gl.glMaterialfv(GL.GL_FRONT, GL.GL_SPECULAR, material.specularColor.getRGBComponents(rgba), 0);
                        gl.glMaterialf(GL.GL_FRONT, GL.GL_SHININESS, material.shininess);
                        gl.glMaterialfv(GL.GL_FRONT, GL.GL_EMISSION, material.emissive.getRGBComponents(rgba), 0);
                    }
                }

                int indexType = 0;
                int vertexIndex = 0;
                int normalIndex = 0;
                int textureIndex = 0;
                gl.glBegin(GL.GL_POLYGON);
                //TODO: the number of vertices for a face is not always 3
                for (int whichVertex=0; whichVertex<tempObj.faces[j].vertIndex.length; whichVertex++) {
                    vertexIndex = tempObj.faces[j].vertIndex[whichVertex];

                    try {
                        normalIndex = tempObj.faces[j].normalIndex[whichVertex];
                        
                        indexType = 0;
                        gl.glNormal3f(tempObj.normals[normalIndex].x, tempObj.normals[normalIndex].y, tempObj.normals[normalIndex].z);

                        if (tempObj.hasTexture) {
                            if (tempObj.texCoords != null) {  
                                textureIndex = tempObj.faces[j].coordIndex[whichVertex];
                                indexType = 1;
                                gl.glTexCoord2f(tempObj.texCoords[textureIndex].u, tempObj.texCoords[textureIndex].v);
                            }
                        }
                        indexType = 2;
                        gl.glVertex3f(tempObj.vertices[vertexIndex].x, tempObj.vertices[vertexIndex].y, tempObj.vertices[vertexIndex].z);
                    }
                    catch (Exception e) {
                        e.printStackTrace();
                        switch (indexType) {
                            case 0:
                            System.err.println("Normal index " + normalIndex + " is out of bounds");
                            break;
                            
                            case 1:
                            System.err.println("Texture index " + textureIndex + " is out of bounds");
                            break;
                            
                            case 2:
                            System.err.println("Vertex index " + vertexIndex + " is out of bounds");
                            break;
                        }
                    }
                }
                gl.glEnd();  
            }

            if (tempObj.hasTexture) {
                Texture t = texture.get(tempObj.materialID);
                if (t != null)
                    t.disable();
            
                gl.glMatrixMode(GL.GL_TEXTURE);
                gl.glPopMatrix();

                gl.glMatrixMode(GL.GL_MODELVIEW);
                gl.glPopMatrix();
            }
        }
        
        // Try this clearing of color so it won't use the previous color
        gl.glColor3f(1.0f, 1.0f, 1.0f);
    }
    
    /**
     * Render the desired object of the model (specified by an id number of 
     * the object)
     * 
     * @param gl
     * @param id
     */
    public void renderBoundsOfObject(GL gl, int id, Model model) {
        if (id >=0 && id <= model.getNumberOfMeshes()) {
            if (model.getMesh(id).bounds != null) {
                drawBounds(gl, model.getMesh(id).bounds);
            }
        }
    }
    

    /**
     * Draw the boundary of the model (the large box representing the entire 
     * model and not the object in it)
     * 
     * @param gLDrawable
     */
    private void genModelBoundsList(GLAutoDrawable gLDrawable, Model model) {
        GL gl = gLDrawable.getGL();
        drawBounds(gl, model.getBounds());
    }
    
    /**
     * Draw the boundary of the model (the large box representing the entire 
     * model and not the object in it)
     * 
     * @param gl
     */
    private void genModelBoundsList(GL gl, Model model) {
        drawBounds(gl, model.getBounds());
    }
    
    /**
     * Draw the boundaries over all of the objects of the model
     *
     * @param gLDrawable
     */
    private void genObjectBoundsList(GLAutoDrawable gLDrawable, Model model) {
        GL gl = gLDrawable.getGL();
        genObjectBoundsList(gl, model);
    }  
    
    /**
     * Draw the boundaries over all of the objects of the model
     * 
     * @param gl
     */
    private void genObjectBoundsList(GL gl, Model model) {
        for (int i=0; i<model.getNumberOfMeshes(); i++) {
            if (model.getMesh(i).bounds != null) {
                drawBounds(gl, model.getMesh(i).bounds);
            }
        }               
    }

    /** 
     * Draws the bounding box of the object using the max and min extrema 
     * points.
     *
     * @param gl
     * @param bounds
     */
    private void drawBounds(GL gl, Bounds bounds) {      
        // Front Face
        gl.glBegin(GL.GL_LINE_LOOP);
            gl.glVertex3f(bounds.min.x, bounds.min.y, bounds.min.z);
            gl.glVertex3f(bounds.max.x, bounds.min.y, bounds.min.z);
            gl.glVertex3f(bounds.max.x, bounds.max.y, bounds.min.z);
            gl.glVertex3f(bounds.min.x, bounds.max.y, bounds.min.z);
        gl.glEnd();

        // Back Face
        gl.glBegin(GL.GL_LINE_LOOP);
            gl.glVertex3f(bounds.min.x, bounds.min.y, bounds.max.z);
            gl.glVertex3f(bounds.max.x, bounds.min.y, bounds.max.z);
            gl.glVertex3f(bounds.max.x, bounds.max.y, bounds.max.z);
            gl.glVertex3f(bounds.min.x, bounds.max.y, bounds.max.z);
        gl.glEnd();            

        // Connect the corners between the front and back face.
        gl.glBegin(GL.GL_LINES);
            gl.glVertex3f(bounds.min.x, bounds.min.y, bounds.min.z);
            gl.glVertex3f(bounds.min.x, bounds.min.y, bounds.max.z);

            gl.glVertex3f(bounds.max.x, bounds.min.y, bounds.min.z);
            gl.glVertex3f(bounds.max.x, bounds.min.y, bounds.max.z);

            gl.glVertex3f(bounds.max.x, bounds.max.y, bounds.min.z);
            gl.glVertex3f(bounds.max.x, bounds.max.y, bounds.max.z);

            gl.glVertex3f(bounds.min.x, bounds.max.y, bounds.min.z);
            gl.glVertex3f(bounds.min.x, bounds.max.y, bounds.max.z);
        gl.glEnd();
    }
    
    /**
     * Convert an Unsigned byte to integer
     * 
     * @param b
     * @return
     */
    public int unsignedByteToInt(byte b) {
      return (int) b & 0xFF;
    }
  
    /**
     * Convert integer to float
     * 
     * @param i
     * @return
     */
    public float intToFloat(int i) {
        return (float) i / 255.0f;
    }
    
    public class DisplayListCache {
        private HashMap <Object, Integer>listCache;

        /** Creates a new instance of WWDisplayListCache */
        private DisplayListCache()  {
            listCache = new HashMap<Object, Integer>();
        }

        public void clear() {
            listCache.clear();
        }

        public int get(Object objID)  {
            if (listCache.containsKey(objID))
                return listCache.get(objID);
            else
                return -1;
        }

        public void remove(Object objID, GL gl, int howMany) {
            Integer list = listCache.get(objID);

            if(list != null)
                gl.glDeleteLists(list, howMany);
            
            listCache.remove(objID);
        }

        /**
         * Returns an integer identifier for an OpenGL display list based on the 
         * object being passed in.   If the object already has a display list 
         * allocated, the existing ID is returned.
         */
        public int generateList(Object objID, GL gl, int howMany) {
            Integer list = null;        

            list = listCache.get(objID);
            if(list == null){
                list  = new Integer(gl.glGenLists(howMany));
                listCache.put(objID, list);            
            }       

            return list;
        }    
    }
}