#!/usr/bin/python

import glob
import os
import sys
import md5
import stat
import mmap

MAX_CHECK_SIZE = 1073741824

class Kechikechi(object):
    def __init__(self):
        self.fileMap = {}
        self.totalReduce = 0
        self.linkedCnt = 1
        self.totalCnt = 1

    def __getFileMD5(self, filename):
        st = os.stat(filename)
        size = st[stat.ST_SIZE]
        f = open(filename, "rb")
        content = mmap.mmap(f.fileno(), size, access=mmap.ACCESS_READ)
        try:
            try:
                m = md5.md5(content)
            except IOError, e:
                print "not found %s" % filename
                raise e
        finally:
            content.close()
            f.close()

        return m

    def __getBaseFilename(self, filename, digest, st):
        key = "%s%d_%d_%d_d" % (digest.digest(),
                                st[stat.ST_MODE],
                                st[stat.ST_UID],
                                st[stat.ST_GID])
        try:
            baseFilename = self.fileMap[key]
        except KeyError, e:
            self. fileMap[key] = filename
            baseFilename = None

        return baseFilename

    def __createLink(self, base, filename, tmp):
        os.link(base, "%s.%s" % (filename, tmp))
        os.remove(filename)
        os.rename("%s.%s" % (filename, tmp), filename)

    def __makeFileMap(self, filename):
        self.totalCnt += 1
        st = os.stat(filename)
        size = st[stat.ST_SIZE]
        if size == 0: return
        if size >= MAX_CHECK_SIZE: return

        md5digest = self.__getFileMD5(filename)
        baseFilename = self.__getBaseFilename(filename, md5digest, st)
        if not baseFilename: return

        print "%d / %d: %s (%d : %d)" % (self.linkedCnt, self.totalCnt, filename, size, self.totalReduce)

        print "     ==> %s  " % (baseFilename),

        if os.path.samefile(filename, baseFilename):
            print "="
            return

        try:
            self.__createLink(baseFilename, filename, md5digest.hexdigest())
        except Exception, e:
            print "Error"
            pass
        else:
            print "OK"
            self.totalReduce += size
            self.linkedCnt += 1

    def makeMap(self, dirname):
        islink = os.path.islink
        isfile = os.path.isfile
        isdir  = os.path.isdir

        print "Directory: %s" % dirname

        files = glob.glob("%s/*" % dirname)

        for filename in files:
            if islink(filename): continue
            if isdir(filename):
                self.makeMap(filename)

            elif isfile(filename):
                self.__makeFileMap(filename)


def main():
    ic = Kechikechi()
    if os.name == "nt":
        os.link = lambda base, filename: os.system("fsutil hardlink create \"%s\" \"%s\" > nul" % (filename, base))
        os.path.samefile = lambda x, y: False

    try:
        ic.makeMap(sys.argv[1])
    except IndexError, e:
        ic.makeMap(".")

    print "Total scaned files:  %d files" % ic.totalCnt
    print "Total reduced files: %d files, %d bytes" % (ic.linkedCnt - 1, ic.totalReduce)

if __name__ == '__main__':
    main()