#!/usr/bin/env python
# [http://mail.python.org/pipermail/python-list/2004-March/210555.html]
from Tkinter import *
import os, sys

class Meter(Frame):
    '''A simple progress bar widget.'''
    def __init__(self, master, fillcolor='cyan', text='',
            value=0.0, **kw):
        self.width=350
        self.height=20
        Frame.__init__(self, master, bg='lightpink', width=self.width,
                height=self.height)
        self.configure(**kw)
        
        self._c = Canvas(self, bg=self['bg'],
                        width=self['width'], height=self['height'],
                        highlightthickness=0, relief='flat', bd=0)
        self._c.pack(fill='x', expand=1)
        self._r = self._c.create_rectangle(0, 0, 0, int(self['height']),
                        fill=fillcolor, width=0)
        self._t = self._c.create_text(int(self['width'])/2,
                        int(self['height'])/2, text='')
        
        self.set(value, text)
        self.pack()

    def set(self, value=0.0, text=None):
        if value < 0.0:
            value = 0.0
        elif value > 1.0:
            value = 1.0
        if text == None:
            text = ''
        text = text + str(int(round(100 * value))) + '%'

        try:
            self._c.coords(self._r, 0, 0, int(self['width']) * value,
                    int(self['height']))
            self._c.itemconfigure(self._t, text=text)
            self.master.update()
        except TclError:
            pass

# Default behavior: parse progress from pipe viewer
# [http://www.ivarch.com/programs/pv.shtml]
if __name__=="__main__":
    baseText=''
    if len(sys.argv) > 1:
        baseText = sys.argv[1]+': '

    value = 0.0
    buf=""
    p = Meter(master=Tk())
    currText = baseText
    p.set (value=value, text=currText)
    while 1:
        char = sys.stdin.read(1)
        if char == '':
            break

        buf = buf + char
        if buf[-15:-12] == 'ETA':
            buf = ""
        elif buf[-3:] == '/s]':
            currText = baseText + buf + ': '
        elif buf[-1] == '%':
            value=float(buf[-3:-1])/100

        p.set (value=value, text=currText)