#Charles Power
#Consulted Dylan Ray, UNC Chapel Hill Mathematics

from cImage import *
import sys, traceback

def flag(w, h):
    newimg = EmptyImage(w, h)

    for row in range(h):
        #for each row in (h) height
        for column in range(w):
            #for each column in row
            if column < w/3:
                #if pixel is in 1/3 make red
                red = 255
                green = 0
                blue = 0
            elif column < (w/3 + w/3):
                #if pixel is in 2/3 make white
                red = 255
                green = 255
                blue = 255
            else:
                #if pixel is in 3/3 make blue
                red= 0
                green = 0
                blue = 255


            p = Pixel(red, green, blue)
            newimg.setPixel(column,row,p)

    return newimg

def flip_horizontal(img):
    """Flip the specified image left to right and return the modified image"""
    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
        #iterate through each pixel in row
        for x in range(w):
            #gets current pixel in row
            p = img.getPixel(x,y)
            newimg.setPixel((w-1) - x, y, p)

    return newimg

def sepia_tone(img):
    """Apply the sepia tone transformation to the specified image, and return the modified image"""
    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
    #iterate through each pixel in image
        for  x in range(w):
            #iterate through each pixel in row
            p = img.getPixel(x,y)
            # gets the current pixel's red intensity
            r = p.getRed()
            g = p.getGreen()
            b = p.getBlue()
            #apply formula to get new pixel
            newR = int(r * 0.393 + g * 0.769 + b * 0.189)
            newG = int(r * 0.349 + g * 0.686 + b * 0.168)
            newB = int(r * 0.272 + g * 0.534 + b * 0.131)

            if newR  > 255:
                newR = 255
            if newG  > 255:
                newG = 255
            if newB  > 255:
                newB = 255

            newpixel = Pixel(newR, newG, newB)
            newimg.setPixel(x,y,newpixel)

    return newimg

def convert_to_gray_scale(img):
    """Apply the gray scale transformation to the specified image, and return the modified image"""
    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
    #iterate through each pixel in image
        for  x in range(w):
            #iterate through each pixel in row
            p = img.getPixel(x,y)
            # gets the current pixel's red intensity
            r = p.getRed()
            g = p.getGreen()
            b = p.getBlue()
            #apply formula to get new pixel
            newR = int(r * 0.21 + g * 0.71 + b * 0.07)
            newG = int(r * 0.21 + g * 0.71 + b * 0.07)
            newB = int(r * 0.21 + g * 0.71 + b * 0.07)

            if newR  > 255:
                newR = 255
            if newG  > 255:
                newG = 255
            if newB  > 255:
                newB = 255

            newpixel = Pixel(newR, newG, newB)
            newimg.setPixel(x,y,newpixel)

    return newimg

def flip_vertical(img):
    """Flip the specified image upside down and return the modified image"""
    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
        #iterate through each pixel in row
        for x in range(w):
            #gets current pixel in row
            p = img.getPixel(x,y)
            newimg.setPixel(x, (h-1) - y, p)

    return newimg

def rotate_right_90(img):
    """Rotate the specified image 90 degrees to the right and return the modified image"""
    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(h,w)

    for y in range(h):
        #iterate through each pixel in row
        for x in range(w):
            #gets current pixel in row
            p = img.getPixel(x,y)
            newimg.setPixel(y, x, p)
    return flip_horizontal(newimg)


#construct a new image that
#is a copy of img in which
#each pixel retains all the red
#and loses the green and blue components.
#the function returns the modified image
def red_filter(img):
    """Apply the red filter transformation to the specified image, and return the modified image"""

    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
        for  x in range(w):
           p = img.getPixel(x,y)


           newpixel = Pixel(p.getRed(),0,0)

           newimg.setPixel(x,y,newpixel)

    return newimg

#construct a new image that
#is a copy of img in which
#each pixel's red, green, and blue
#components are replaced with their complement with respect to 255
#the function returns the modified image
def negative(img):
    """Apply the negative transformation to the specified image, and return the modified image"""

    w = img.getWidth()
    h = img.getHeight()

    newimg = EmptyImage(w,h)

    for y in range(h):
        for  x in range(w):
           p = img.getPixel(x,y)


           newpixel = Pixel(255-p.getRed(),255-p.getGreen(),255 - p.getBlue())

           newimg.setPixel(x,y,newpixel)

    return newimg

##DO NOT MODIFY THE FUNCTIONS BELOW
##THEY ARE USED FOR TESTING YOUR FUNCTIONS
##AND DISPLAYING IMAGES

#display the specified image in a window
def display_image(img, t):
    """Display the specified image in a window"""
    win = ImageWin(title = t, width = img.getWidth(), height = img.getHeight())
    img.draw(win)

#don't modify this function
def test_one(transform, filename):
    transformName = str(transform).split()[1]
    print("Starting "+ transformName)

    try:
        #create an image corresponding to the specified file
        img = Image(filename)

        #apply the specified transformation to the image
        img = transform(img)

        #show the transformed image
        display_image(img, transformName)
    except:
        print("\t"+transformName + ":Error")

#don't modify this function
#I will use it to test all your functions
def test_all():
    transforms = [flip_horizontal, sepia_tone, convert_to_gray_scale, flip_vertical, rotate_right_90]
    for t in transforms:
        test_one(t, "penguins.gif")
#test_all()