#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import os
import sys
from subprocess import call
import fnmatch

def compresspic(filepath,boolpng):  
  oldsize = os.stat(filepath).st_size
  if boolpng:
    call("convert " +filepath+" -strip Compressed_tempfile", shell=True) 
  else:
    call("convert " +filepath+" -sampling-factor 4:2:0 -strip -quality 75 -interlace JPEG -colorspace sRGB Compressed_tempfile", shell=True)  
  
  tempfilepath = os.path.join(os.getcwd(),"Compressed_tempfile")
  newsize = os.stat(tempfilepath).st_size    
  compresssize = oldsize - newsize
  
  if (compresssize > 0):
    os.remove(filepath)
    os.rename(tempfilepath,filepath)
    print ("{0} file compressed from {1} to {2} ".format(filepath,oldsize,newsize))
    with open('comressed.txt','a') as f:
      f.write("%s\n" % filepath)
  else:
    os.remove(tempfilepath)
    print ("{0} file already compressed, no need to compress again.)".format(filepath))
    compresssize = 0
    with open('comressed.txt','a') as f:
      f.write("%s\n" % filepath)
  return compresssize
    
#finds present working dir
pwd = os.getcwd()
images =["*.jpg", "*.jpeg", "*.png"]
tot = 0
num = 0
aleadycompressed = [aleadycompressed.rstrip('\n') for aleadycompressed in open('comressed.txt','w+')]
for path, subdirs, files in os.walk(pwd):
  for extensions in images:
    for filename in fnmatch.filter(files, extensions):
      filepath = os.path.join(path, filename)
      if not filepath in aleadycompressed:
        num += 1
        if (extensions =="*.png"):
          boolpng = True
        else:
          boolpng = False
        tot += compresspic(filepath,boolpng)
print ("Total Compression: %d files, compressed %d bytes" % (num, tot))   
print ("Average Compression: %d bytes" % (float(tot)/num))