#!/usr/bin/python

import os, sys

localdir = "/var/lib/pacman/local"

directories = os.listdir(localdir)

def sortbyvalue(dict):
	""" Return a list of (key, value) pairs, sorted by value. """
	_swap2 = lambda (x,y): (y,x)
	mdict = map(_swap2, dict.items())
	mdict.sort()
	mdict = map(_swap2, mdict)
	return mdict

def numfmt(value):
  v = str(float(value)) + '0000'
  i = v.index('.')
  if i < 4:
    return v[:5]
  else:
    return v[:i+2]

def getHumanSize(bytes):
	filesize =  int(bytes)
	if filesize >= 1000*1024*1024:
		filefrmt = "%s GB" % numfmt(filesize/1024.0/1024/1024)
	elif filesize >= 1000*1024:
		filefrmt = "%s MB" % numfmt(filesize/1024.0/1024)
	elif filesize >= 1000:
		filefrmt = "%s KB" % numfmt(filesize/1024.0)
	elif filesize == 0:
		filefrmt = "%i B" % filesize
	return filefrmt

def getpackagesize(dir, currentdir):
	
	description = "/".join([currentdir, "desc"])
	if not os.path.exists(description):
		return
	fd = file(description, 'r')
	lines = fd.read().split('\n')
	fd.close()
	sizeline = size = None
	pos = 0
	for line in lines:
		if sizeline != None and sizeline == pos:
			size = eval(line)
			break
		if "%SIZE%" in line:
			sizeline = pos + 1
		pos +=1
	if size is not None:
		PackageSizesDict[dir] = size
		
if __name__ == '__main__':
	reverse = alpha = False
	if len(sys.argv) > 1:
		for arg in sys.argv[1:]:
			if arg in ("--reverse", "-r"):
				 reverse = True
			if arg in ("--alpha", "-a"):
				 alpha = True
	PackageSizesDict = {}
	for dir in directories:
		currentdir = "/".join([localdir, dir])
		if not os.path.isdir(currentdir):
			continue
		getpackagesize(dir, currentdir)
	if not alpha:	
		PackageSizesListOfTuples = sortbyvalue(PackageSizesDict)
	else:
		PackageSizesListOfTuples = [(key,value) for key,value in PackageSizesDict.keys()]
	if reverse:
		PackageSizesListOfTuples.reverse()
	totalsize = 0
	for thing in PackageSizesListOfTuples:
		package, size = thing
		human = getHumanSize(size)
		string = "%s%s%s%s%s" % (human.rjust(10), " ", package, (45 - len(package)) * " ",  "%i bytes".rjust(20-len(str(size))) % size)
		totalsize += size
		print string
	human = getHumanSize(totalsize)
	print "-"*80
	label = "Total size of packages"
	string = "%s%s%s%s%s" % (human, (10 - len(human)) * " ", label, (45 - len(label)) * " ",  "%i bytes".rjust(20-len(str(totalsize))) % totalsize)
	print string