/*
 * Copyright (c) 2010, 2014, Oracle and/or its affiliates.
 * All rights reserved. Use is subject to license terms.
 *
 * This file is available and licensed under the following license:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  - Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the distribution.
 *  - Neither the name of Oracle Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package eu.mihosoft.jcsg.ext.openjfx.importers.obj;

import static eu.mihosoft.jcsg.ext.openjfx.importers.obj.ObjImporter.log;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.scene.image.Image;
import javafx.scene.paint.Color;
import javafx.scene.paint.Material;
import javafx.scene.paint.PhongMaterial;


/** Reader for OBJ file MTL material files. */
public class MtlReader {

    private String baseUrl;

    public MtlReader(String filename, String parentUrl) {
        baseUrl = parentUrl.substring(0,parentUrl.lastIndexOf('/')+1);
        String fileUrl = baseUrl + filename;
        try {
            URL mtlUrl = new URL(fileUrl);
            log("Reading material from filename = " + mtlUrl);
            read(mtlUrl.openStream());
        } catch (FileNotFoundException ex) {
            System.err.println("No material file found for obj. ["+fileUrl+"]");
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
    
    public MtlReader(InputStream stream) {

        try {
            log("Reading material from stream");
            read(stream);
        } catch (FileNotFoundException ex) {
            System.err.println("No material file found for obj. [stream]");
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }

    private Map<String, Material> materials = new HashMap<>();
    private PhongMaterial material = new PhongMaterial();
    private boolean modified = false;

    private void read(InputStream inputStream) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
        String line;
        String name = "default";
        while ((line = br.readLine()) != null) {
            try {
                if (line.isEmpty() || line.startsWith("#")) {
                    // comments and empty lines are ignored
                } else if (line.startsWith("newmtl ")) {
                    addMaterial(name);
                    name = line.substring("newmtl ".length());
                } else if (line.startsWith("Kd ")) {
                    material.setDiffuseColor(readColor(line.substring(3)));
                    modified = true;
                } else if (line.startsWith("Ks ")) {
                    material.setSpecularColor(readColor(line.substring(3)));
                    modified = true;
                } else if (line.startsWith("Ns ")) {
                    material.setSpecularPower(Double.parseDouble(line.substring(3)));
                    modified = true;
                } else if (line.startsWith("map_Kd ")) {
                    material.setDiffuseColor(Color.WHITE);
                    material.setDiffuseMap(loadImage(line.substring("map_Kd ".length())));
//                    material.setSelfIlluminationMap(loadImage(line.substring("map_Kd ".length())));
//                    material.setSpecularColor(Color.WHITE);
                    modified = true;
                    //            } else if (line.startsWith("illum ")) {
                    //                int illumNo = Integer.parseInt(line.substring("illum ".length()));
                    /*
                        0	 Color on and Ambient off 
                        1	 Color on and Ambient on 
                        2	 Highlight on 
                        3	 Reflection on and Ray trace on 
                        4	 Transparency: Glass on 
                             Reflection: Ray trace on 
                        5	 Reflection: Fresnel on and Ray trace on 
                        6	 Transparency: Refraction on 
                             Reflection: Fresnel off and Ray trace on 
                        7	 Transparency: Refraction on 
                             Reflection: Fresnel on and Ray trace on 
                        8	 Reflection on and Ray trace off 
                        9	 Transparency: Glass on 
                             Reflection: Ray trace off 
                        10	 Casts shadows onto invisible surfaces 
                     */
                } else {
                    log("material line ignored for " + name + ": " + line);
                }
            } catch (Exception ex) {
                Logger.getLogger(MtlReader.class.getName()).log(Level.SEVERE, "Failed to parse line:" + line, ex);
            }
        }
        addMaterial(name);
    }

    private void addMaterial(String name) {
        if (modified) {
            if (!materials.containsKey(name)) {
                materials.put(name, material);
            } else {
                log("This material is already added. Ignoring " + name);
            }
            material = new PhongMaterial(Color.WHITE);
        }
    }

    private Color readColor(String line) {
        String[] split = line.trim().split(" +");
        float red = Float.parseFloat(split[0]);
        float green = Float.parseFloat(split[1]);
        float blue = Float.parseFloat(split[2]);
        return Color.color(red, green, blue);
    }

    private Image loadImage(String filename) {
        filename = baseUrl + filename;
        log("Loading image from " + filename);
        Image image = new Image(filename);
        return new Image(filename);
    }

    public Map<String, Material> getMaterials() {
        return Collections.unmodifiableMap(materials);
    }
}
