'''
The MIT License (MIT)

Copyright (c) 2013 noamraph

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
'''

__all__ = ['tqdm', 'trange']

import sys
import time


def format_interval(t):
    mins, s = divmod(int(t), 60)
    h, m = divmod(mins, 60)
    if h:
        return '%d:%02d:%02d' % (h, m, s)
    else:
        return '%02d:%02d' % (m, s)


def format_meter(n, total, elapsed):
    # n - number of finished iterations
    # total - total number of iterations, or None
    # elapsed - number of seconds passed since start
    if n > total:
        total = None
    
    elapsed_str = format_interval(elapsed)
    rate = '%5.2f' % (n / elapsed) if elapsed else '?'
    
    if total:
        frac = float(n) / total
        
        N_BARS = 10
        bar_length = int(frac*N_BARS)
        bar = '#'*bar_length + '-'*(N_BARS-bar_length)
        
        percentage = '%3d%%' % (frac * 100)
        
        left_str = format_interval(elapsed / n * (total-n)) if n else '?'
        
        return '|%s| %d/%d %s [elapsed: %s left: %s, %s iters/sec]' % (
            bar, n, total, percentage, elapsed_str, left_str, rate)
    
    else:
        return '%d [elapsed: %s, %s iters/sec]' % (n, elapsed_str, rate)


class StatusPrinter(object):
    def __init__(self, file):
        self.file = file
        self.last_printed_len = 0
    
    def print_status(self, s):
        self.file.write('\r'+s+' '*max(self.last_printed_len-len(s), 0))
        self.file.flush()
        self.last_printed_len = len(s)


def tqdm(iterable, desc='', total=None, leave=False, file=sys.stderr,
         mininterval=0.5, miniters=1):
    """
    Get an iterable object, and return an iterator which acts exactly like the
    iterable, but prints a progress meter and updates it every time a value is
    requested.
    'desc' can contain a short string, describing the progress, that is added
    in the beginning of the line.
    'total' can give the number of expected iterations. If not given,
    len(iterable) is used if it is defined.
    'file' can be a file-like object to output the progress message to.
    If leave is False, tqdm deletes its traces from screen after it has
    finished iterating over all elements.
    If less than mininterval seconds or miniters iterations have passed since
    the last progress meter update, it is not updated again.
    """
    if total is None:
        try:
            total = len(iterable)
        except TypeError:
            total = None
    
    prefix = desc+': ' if desc else ''
    
    sp = StatusPrinter(file)
    sp.print_status(prefix + format_meter(0, total, 0))
    
    start_t = last_print_t = time.time()
    last_print_n = 0
    n = 0
    for obj in iterable:
        yield obj
        # Now the object was created and processed, so we can print the meter.
        n += 1
        if n - last_print_n >= miniters:
            # We check the counter first, to reduce the overhead of time.time()
            cur_t = time.time()
            if cur_t - last_print_t >= mininterval:
                sp.print_status(prefix + format_meter(n, total, cur_t-start_t))
                last_print_n = n
                last_print_t = cur_t
    
    if not leave:
        sp.print_status('')
        sys.stdout.write('\r')
    else:
        if last_print_n < n:
            cur_t = time.time()
            sp.print_status(prefix + format_meter(n, total, cur_t-start_t))
        file.write('\n')


def trange(*args, **kwargs):
    """A shortcut for writing tqdm(range()) on py3 or tqdm(xrange()) on py2"""
    try:
        f = xrange
    except NameError:
        f = range
    
    return tqdm(f(*args), **kwargs)
