#!/usr/bin/env python

from PIL import Image, ImageOps
import wave, math, array, argparse, sys, timeit

def parser():
    parser = argparse.ArgumentParser()

    # Specified command options and its helps message

    parser.add_argument ("INPUT_FILE", help="Name of the image to be converted.")
    parser.add_argument ("-r", "--rotate", help="Rotate image 90 degrees.", action='store_true')
    parser.add_argument ("-i", "--invert", help="Invert image colors.", action='store_true')
    parser.add_argument ("-o", "--output", help="Name of the output wav file. Default value: out.wav).")
    parser.add_argument ("-b", "--bottom", help="Bottom frequency range. Default value: 200.", type=int)
    parser.add_argument ("-t", "--top", help="Top frequency range. Default value: 20000.", type=int)
    parser.add_argument ("-p", "--pixels", help="Pixels per second. Default value: 30.", type=int)
    parser.add_argument ("-s", "--sampling", help="Sample rate. Default value: 44100.", type=int)

    # Create "arguments" object based on user input
    arguments = parser.parse_args()

    # Default values

    min_freq    = 200
    max_freq    = 20000
    sample_rate = 44100
    pixels      = 30
    output      = "out.wav"
    rotate      = False
    invert      = False

    # Check arguments values
    if arguments.output:
        output = arguments.output
    if arguments.bottom:
        min_freq = arguments.bottom
    if arguments.top:
        max_freq = arguments.top
    if arguments.pixels:
        pixels = arguments.pixels
    if arguments.sampling:
        sample_rate = arguments.sampling
    if arguments.rotate:
        rotate = True
    if arguments.invert:
        invert = True

    print ("------------------------------------ Simple Image To Sound Script ------------------------------------\n")
    print ('Input file: %s.' % arguments.INPUT_FILE)
    print ('Frequency range: %d - %d.' % (min_freq, max_freq))
    print ('Pixels per second: %d.' % pixels)
    print ('Sampling rate: %d.' % sample_rate)
    print ('Rotate Image: %s.' % ('Yes' if rotate else 'No'))

    return (arguments.INPUT_FILE, output, min_freq, max_freq, pixels, sample_rate, rotate, invert)

def convert (INPUT_FILE, output, min_freq, max_freq, pixels, sample_rate, rotate, invert):
    image = Image.open (INPUT_FILE).convert ('L')

    # rotate image if requested
    if rotate:
        image = image.rotate (90)

    # invert image if requested
    if invert:
        image = ImageOps.invert (image)

    output = wave.open (output, 'w')
    output.setparams ((1, 2, sample_rate, 0, 'NONE', 'not compressed'))

    freq_range = max_freq - min_freq
    interval = freq_range / image.size[1]

    samples = sample_rate // pixels
    data = array.array ('h')

    # Converting process start
    time_start = timeit.default_timer()

    for x in range (image.size[0]):
        row = []
        for y in range (image.size[1]):
            yinv = image.size[1] - y - 1
            amplitude = image.getpixel ((x,y))
            if (amplitude > 0):
                row.append (gen_wave (yinv * interval + min_freq, amplitude, samples, sample_rate))

        for i in range(samples):
            for j in row:
                try:
                    data[i + x * samples] += j[i]
                except (IndexError):
                    data.insert (i + x * samples, j[i])
                except (OverflowError):
                    if j[i] > 0:
                      data[i + x * samples] = 32767
                    else:
                      data[i + x * samples] = -32768

        sys.stdout.write ("Conversion progress: %d%%   \r" % (float(x) / image.size[0] * 100))
        sys.stdout.flush()

    output.writeframes (data.tobytes())
    output.close()

    # Converting process end
    time_end = timeit.default_timer()

    print ("Conversion progress: 100%")
    print ("Success. Completed in %d seconds." % int(time_end - time_start))

def gen_wave (frequency, amplitude, samples, sample_rate):
    cycles = samples * frequency / sample_rate
    wave = []
    for i in range(samples):
        x = math.sin (float (cycles) * 2 * math.pi * i / float (samples)) * float (amplitude)
        wave.append (int (math.floor (x)))
    return wave

if __name__ == '__main__':
    input_choice = parser()
    convert (*input_choice)