"""
Print status dots

  Revision History
  ----------------

  Version 1.0 -- December 28, 1998, Andrew Sterian (asterian@umich.edu)
     * Initial release
"""

import sys

_enable=1
_count=0
_dots=0
_total=0
_fid = None

def Enable(onoff):
  "Set boolean state of dot display"
  global _enable
  _enable = onoff

def InitDots(N, fid=None, NumDots=80):
  "Initialize dot display for N iterations of something"
  global _dots
  global _count
  global _enable
  global _total
  global _fid

  if not _enable: return

  _fid = fid
  if not _fid: _fid=sys.stdout

  if N >= 1:
    _dots = (N-1)/NumDots+1
    _total = (N-1)/_dots
    _fid.write('*' * _total)
    _fid.flush()
  else:
    _dots = 0
    _total = 0
  _count = _dots

def Dot():
  "Count down one iteration"
  global _dots
  global _count
  global _enable
  global _total
  global _fid

  if not _enable: return
  if _total <= 0: return

  _count = _count - 1
  if _count <= 0:
    _fid.write('\b \b')
    _fid.flush()
    _count = _dots
    _total = _total - 1

def Clear():
  "Erase all remaining dots"
  global _dots
  global _count
  global _total
  global _enable

  if not _enable: return

  if _total > 0: 
    _fid.write('\b \b' * _total)
    _fid.flush()
  _total = _dots = _count = 0

if __name__ == "__main__":
  import time

  print 'Testing dots...'
  InitDots(1000)
  for i in range(1000):
    time.sleep(0.001)
    Dot()

  print 'Testing clear function...'
  InitDots(1000)
  for i in range(500):
    time.sleep(0.001)
    Dot()
  Clear()

  print 'Testing alternate stream and dot count...'
  InitDots(1000, sys.stderr, 40)
  for i in range(1000):
    time.sleep(0.001)
    Dot()