import sys
import os
from Tkinter import *
import tkFileDialog
import subprocess
import platform

def setPixel(image, pos, color):
	r,g,b = [color]*3
	x,y = pos
	image.put("#%02x%02x%02x" % (r,g,b), (x, y))


def manualLoadFile(filename):
	global fileOpen
	global img
	f = open(filename, 'r')
	data1 = f.readlines()
	# remove comments, newlines, and blank lines
	data = [x[:-1] for x in data1 if (x[0] != '#' and x != '\n')]

	if data[0] != "P2":
		print "Error: Incorrect Magic Number"
		return
	size = data[1].split()
	maxVal = int(data[2])

	# remove the magic number, size, maxVal from data array
	del data[0]
	del data[0]
	del data[0]

	img = PhotoImage(width = int(size[0]), height = int(size[1]))

	num = 0
	curPos = [0,0]
	for i in data:
		line = i.split()
		for j in line:
			setPixel(img, curPos, int(float(j) / float(maxVal) * 255))
			num += 1
			curPos[0] += 1
			if curPos[0] >= int(size[0]):
				curPos[0] = 0
				curPos[1] += 1
	imageLabel.configure(image = img)
	imageLabel.image = img
	fileOpen = True
	return True


def loadFile(filename):
	global fileOpen
	global img
	try:			# to load as a binary pgm file
		img = PhotoImage(file=filename)
		imageLabel.configure(image = img)
		imageLabel.image = img
		fileOpen = True

	except Exception, e:
		# try to load it with our function for ascii pgm file!
		if manualLoadFile(filename):
			pass 	#  all good
		else:
			print "Cannot Open File"

	imageLabel.pack(fill=BOTH,expand=1)


def newWindow(filename):
	subprocess.Popen(["python", sys.argv[0], filename], stdout=subprocess.PIPE, stdin=subprocess.PIPE, stderr=subprocess.PIPE)


def pickFiles():
	global fileOpen
	filename = tkFileDialog.askopenfilename(multiple=1)
	if filename == "":
		return
	if os.name == 'nt':
		if platform.release() == 'XP': #If windows, handle files differently #THIS IS WINDOWS XP
			filename = filename[1:-1] # Strip the begining and end brackets
			filename = filename.split("} {") #split it into an array

		if platform.release() == '7' or platform.release() == 'Vista': #If windows, handle files differently #THIS IS WINDOWS 7 (AND PROBABLY VISTA)
	                if filename.count("{") != 0:
	                	filename = filename[1:-1] # Strip the begining and end brackets
	                	filename = filename.split("} {") #split it into an array
	                else:
	                        filename = [filename]
	print filename
	if not fileOpen:
		loadFile(filename[0])
		for i in filename[1:]:
			newWindow(i)
	else:
		for i in filename:
			newWindow(i)


# main routine starts here after our functions are defined

root = Tk()
root.wm_title("DisplayPGM")

location = sys.argv[0]

f = Canvas(root, width = 500, height = 500)
f.pack()
imageLabel = Label(f)

img = None
fileOpen = False

menubar = Menu(root,tearoff= 0)
m = Menu(menubar)
menubar.add_cascade(label="File", menu=m)
m.add_command(label="Open", command = pickFiles)
m.add_command(label="Exit", command = root.quit)
root.config(menu = menubar)

if len(sys.argv) > 1:
	loadFile(sys.argv[1])

root.mainloop()