import re  		#for subn
import string 	#for replace
import glob 	#for find all files of a directory
import sys 		#for sys.argv, sys.exit(0)
import os.path 	#for isdir
import os 		#for listdir

#############################################################################################
# Configuration section 

#Global switches. Set these to 1 (on) or 0 (off)
Use_command_line_parameters = 1
Use_regular_expressions = 0 # You must be aware of Python's regular expressions to use this
Verbose = 1                 # Print replaced lines in DOS box
Search_subdirectories = 1
Search_only = 0
Make_backup = 1
Backup_suffix = ".bak"

#Global variables
TempFile = "c:\\tmp\\tmp.tmp" #The temporary file
FileFilter = ["*.html"] #The type of file to modify

# Here is another example, you can add as many extensions as you like.
# All matching files will all be modified
#FileFilter = ["*.htm","*.html"]

# End configuration section
##############################################################################################

if Use_command_line_parameters:
	if len(sys.argv) <> 4: # Tests the number of command line parameters
		print "Usage: python replace.py   " #console display
		sys.exit(0) #abandon
	Directory = sys.argv[1]
	String_to_replace = sys.argv[2]
	Replacing_string = sys.argv[3]
else: # up to you to change these strings
	Directory="."
	String_to_replace = "bad"
	Replacing_string = "worse"

def replace_in(filename, str_to_replace, rep_string):
	try:
		ifh = open(filename,"r")
	except:
		print "cannot open",filename
		sys.exit(0)
	try:
		ofh = open(TempFile,"w")
	except:
		print "cannot open",TempFile
		sys.exit(0)
	nsub_total = 0
	while 1:
		line = ifh.readline()
		if not line:
			break
		else:
			if Verbose:
				if string.count(line,str_to_replace):
					print line
			if Use_regular_expressions:
				newline,nsub=re.subn(str_to_replace, rep_string, line)
				nsub_total += nsub
			else:
				newline=string.replace(line,str_to_replace, rep_string)
				if line <> newline:
					nsub_total += string.count(line, str_to_replace)
			ofh.write(newline)
	
	ifh.close()
	ofh.close()
	if Search_only == 0:
		if nsub_total:
			if Make_backup:
				copy_file(filename, filename+Backup_suffix)# Do this first!!!
			copy_file(TempFile,filename)
	print nsub_total,"replacements done in",filename
	
def copy_file(from_file, to_file):
	try:
		ifh = open(from_file,"r")
	except:
		print "Cannot open",from_file
		sys.exit(1)
	try:
		ofh = open(to_file,"w")
	except:
		print "Cannot open",to_file
		sys.exit(2)
	while 1:
		line = ifh.readline()
		if not line:
			break
		else:
			ofh.write(line)
	ifh.close()
	ofh.close()

def search_and_replace(path):
	global String_to_replace, Replacing_string,Search_subdirectories
	for pattern in FileFilter:
		for filename in glob.glob(path+'\\'+pattern):
			print "replacing in",filename
			replace_in(filename,String_to_replace,Replacing_string)
	if Search_subdirectories:
		for entry in os.listdir(path):
			if os.path.isdir(path+"\\"+entry): # if it's a directory (could have been a file)
				search_and_replace(path+"\\"+entry)
# Go!	
search_and_replace(Directory)