/**
 * Class for creating a template for a simple Java program
 * 
 * @author Pat Troy: troy AT uic DOT edu
 */

// import the library with the color information
import java.awt.Color;

// Note the name of the class in the following line MUST
// match the name of the file.  This is stored in a file
// named: Template.java 
public class Lect1012c
{
  
  public static void main (String[] args) 
  {
    System.out.println("Begin Java Exection");
    System.out.println("");

    // Select two pictures
    String filename = FileChooser.pickAFile();
    System.out.println (filename);
    Picture pict1 = new Picture(filename);
    filename = FileChooser.pickAFile();
    System.out.println (filename);
    Picture pict2 = new Picture(filename);
    
    // call the method to modify the picture
    Picture anotherPicture;
    anotherPicture = modifyPicture (pict1, pict2);
    
    // display the picture
    anotherPicture.show();
    
    // Save the picture
    //String fname;
    //fname = FileChooser.pickAFile();
    //System.out.println ("File: " + filename);
    //pict1.write (fname);

    System.out.println("");
    System.out.println("End Java Exection");
  }   // end of the method main
  
  
 
  public static Picture modifyPicture (Picture pictA, Picture pictB)
  {
    // get the width and height of the picture
    int width = pictA.getWidth();
    int height = pictA.getHeight();
    //System.out.println ("Width: " + width);
    //System.out.println ("Height: " + height);
    
    // create a new Picture to store the grayScale image
    Picture pictC = new Picture (width, height);
    
    // set up a nested loop (one loop inside another) to access each pixel
    int xLoopCounter;
    int yLoopCounter;
    
    // the outer loop varies the X position (which column the pixel is in)
    for ( xLoopCounter = 0 ; xLoopCounter < width ; xLoopCounter++ )
    {
      // the inner loop varies the Y position (which row the pixel is in)
      for ( yLoopCounter = 0 ; yLoopCounter < height ; yLoopCounter++ )
      {
        // access a pixel and its colors from the first picture
        Pixel pA = pictA.getPixel (xLoopCounter, yLoopCounter); 
        int redA = pA.getRed();
        int greenA = pA.getGreen();
        int blueA = pA.getBlue();
        
        // access a pixel and its colors from the second picture
        Pixel pB = pictB.getPixel (xLoopCounter, yLoopCounter); 
        int redB = pB.getRed();
        int greenB = pB.getGreen();
        int blueB = pB.getBlue();
        
        // modify the color value as needed 
        double percentOfWidth = (1.0 * xLoopCounter) / (double)(width);  // we want float division
        int red = (int)((1.0 - percentOfWidth)*redA + percentOfWidth*redB);
        int green = (int)((1.0 - percentOfWidth)*greenA + percentOfWidth*greenB);
        int blue = (int)((1.0 - percentOfWidth)*blueA + percentOfWidth*blueB);
        
        // save the modified color values
        Pixel pC = pictC.getPixel (xLoopCounter, yLoopCounter);
        pC.setRed(red);
        pC.setGreen(green);
        pC.setBlue(blue);
      }
    }
    
    // add the code to return the newly created picture
    return pictC;
  }  // end of the method to modify the picture
  
} // end of Lect914b class