#!/usr/bin/env python3.1
"""Shitty little script that spits out a Google chart of activity in a repo over time"""
import sys
import subprocess
import re
import collections
import itertools
import datetime
 
WHITESPACE = re.compile("[ \t\n\r]+")
 
GIT_LOG = "git log --pretty=medium --numstat --date=short --all".split(" ")
 
log = subprocess.Popen(GIT_LOG, stdout=subprocess.PIPE).stdout
 
current_insertions = 0
current_deletions = 0
 
first_date = last_date = None
 
insertions = collections.defaultdict(int)
deletions = collections.defaultdict(int)
 
for line in itertools.chain(log, [b"Date: "]):
    line = line.decode()
    
    if line.startswith("Date: "):
        date = line.partition("Date: ")[2].strip()
 
        insertions[last_date] += current_insertions
        deletions[last_date] += current_deletions
 
        current_insertions = current_deletions = 0        
 
        if first_date is None:
            first_date = date
        
        if date:
            last_date = date
 
    
    if line[0] in set("0123456789"):
        written, deleted, filename, *_ = WHITESPACE.split(line)
        current_insertions = int(written)
        current_deletions = int(deleted)
 
DAY = datetime.timedelta(days=1)
        
def date_range(start, end):
    """takes two YYYY-MM-DD dates and yields their inclusive range"""
    
    start_ymd = list(map(int, start.split("-")))
    end_ymd = list(map(int, end.split("-")))
 
    if end_ymd < start_ymd:
        start_ymd, end_ymd = end_ymd, start_ymd
    
    start_date = datetime.date(*start_ymd)
    end_date = datetime.date(*end_ymd)
 
    now = start_date
 
    while now <= end_date:
        yield(str(now))
        now += DAY
 
i_list = []
d_list = []
        
for day in date_range(first_date, last_date):
    i_list.append(insertions[day])
    d_list.append(deletions[day])
 
highest = max(map(sum, zip(i_list, d_list)))
 
i_list = [v * 100 / highest for v in i_list]
d_list = [v * 100 / highest for v in d_list]
 
width = 12 * len(d_list) + 16
 
print("http://chart.apis.google.com/chart?cht=bvs&"
      "chs={}x200&chd=t:{}|{}&chco=FF4444,44FF44&chbh=10,2,0"
      .format(width,
              ",".join(map(str, d_list)),
              ",".join(map(str, i_list))))