#! /usr/bin/env python
"""simple class to iterate over the lines
of a file or standard input
$Id: Utility.py,v 1.1 2004/10/10 02:53:09 nghoffma Exp $
"""

import sys

class inFile:
	def __init__( self, filename='' ):
		if filename == '':
			self.__fo = sys.stdin
		else:
			try:
				self.__fo = open( filename, 'r' )
			except IOError:
				print '\n\n*\n*%30s\n*' % 'Utility.inFile'
				print filename, "does not exist"
				return
			
	def __getitem__( self, index ):
		
		#try to read a line
		line = self.__fo.readline()
		#if nothig is left to read
		if line == "":
			#close file object
			self.__fo.close()
			#raise index error to get out of for loops
			raise IndexError
		else:
			return line
			
def niceTable(dataArray, gutter=2, columnGuide=0):
	"""Writes a table with left-justified columns separated by
	space characters. Each column is (gutter) spaces wider than the widest 
	element in the column. dataArray is a list of lists : dataArray[line][element]
	if columnGuide= a character, places strings of that char repeated over each column.
	Returns a string."""
		
	lineCount = len(dataArray)
	###figure out number of columns
	colCount = 0
	for line in dataArray:
		colCount = max([colCount, len(line)])
	
	### determine column widths
	colWidths = [0]*colCount
	for j in range(colCount):
		for i in range(lineCount):
			try:
				thisLen = len(dataArray[i][j])
			except IndexError:
				dataArray[i].append('')
				thisLen = 0
			
			colWidths[j] = max([colWidths[j], thisLen + gutter])
	
	fstr = '%%-%is'*colCount % tuple(colWidths) + '\n'
	
	outstr = ''
	
	if columnGuide:
		guideList = []
		for w in colWidths:
			guideList.append(columnGuide*(w-gutter))
		
		outstr = outstr + fstr % tuple(guideList)
	
	for line in dataArray:
		outstr = outstr + fstr % tuple(line)
		
	return outstr
	
def describe():
	"""
Utility.py

Miscellaneous utility functions.
"""
	
	print describe.__doc__

if __name__ == '__main__':
	describe()