#!/usr/bin/python
# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
# vi: set ft=python sts=4 ts=4 sw=4 et:
#
# Create a figure with the NeuroDebian repo subscription stats from the apache logs
# Requires out put of
#  zgrep "GET /lists/[-a-z\.]\+ HTTP" neuro.debian.net-*access.log* | sed -e 's,[^:]*:\([0-9\.]\+\).*\[\(.*\):.*:.*:.*/lists/\(.*\) HTTP.*,\2;\3;\1,' -e 's,/, ,g'
# either from a file or on stdin. Needs output filename as the only argument

import fileinput
import sys
from datetime import datetime
import numpy as np
import matplotlib
matplotlib.use('Agg')
import pylab as pl
from matplotlib.dates import date2num, num2date
from matplotlib.dates import YearLocator, MonthLocator, DateFormatter
from matplotlib.font_manager import FontProperties
from ConfigParser import SafeConfigParser
from math import ceil

dt = [('ip', '|S16'),
      ('loc', '|S3'),
      ('suite', '|S20'),
      ('date', float)]


def make_figure(data, ymax=None):
    fig = pl.figure(figsize=(14,3))
    distros = ('Debian', 'Ubuntu')
    # Sorting is actually seems to be not needed on Python 2.7
    # which probably returns release codenames in the order as
    # in the config file which is already correct
    # But since our server is still on previous stable release
    # let's sort for now explicitly
    # 9999 for 'nd' == 'sid'
    sorting_ids = dict([(x[0], len(x[1])>2 and float(x[1][2:]) or 9999)
                        for x in cfg.items('release backport ids')])
    for idistro, distro in enumerate(distros):
        ax = fig.add_subplot(1, len(distros), idistro+1)
        suites = [code for code in cfg.options('release codenames')
                  if cfg.get('release codenames', code).count(distro)]
        # sort suites according to backport ids
        # and in reverse order so the freshiest is on top
        suites = sorted(suites,
                        cmp=lambda x,y: cmp(sorting_ids[x], sorting_ids[y]),
                        reverse=True)
        plot_datehist(ax, data, 10, suites, title=distro, ymax=ymax)
    fig.autofmt_xdate()
    return fig


def plot_datehist(ax, data, bins, suites, title=None, ymax=None):
    colors=['#ff0088', '#20435C', '#45902C', '#E08720']
    linestyle=['-', '--']
    global_x_max = None
    global_x_min = None
    global_y_max = None
    for i, suite in enumerate(suites):
        dates = data['date'][data['suite'] == suite]
        # history in days
        history_length = dates.max() - dates.min()
        # make approx monthly bins, smaller bins yield spiky curves
        # needs new=True to work with oldish numpy
        (hist, bin_edges) = np.histogram(dates, np.ceil(history_length/30.))
        if False:
            # debug output ;-)
            print dates.min(), num2date(dates.min()), dates.max(), \
                  num2date(dates.max()), history_length
            print bin_edges
        if len(bin_edges) < 2:
            # protect against single data point entries by ignoring them
            # wouldn't be able to draw a line anyway ;-)
            continue
        width = bin_edges[1] - bin_edges[0]
        # think lines
        y = hist / width
        global_y_max = max(max(y), global_y_max)
        ax.plot(bin_edges[:-1]+(width/2), y,
                label=suite, color=colors[i%4], linestyle=linestyle[i//4], lw=2)
        # transparent curve shading
        ax.fill_between(bin_edges[:-1]+(width/2), 0, hist / width, alpha=0.2,
                        label=suite, color=colors[i%4])
        # figure out axis limits to avoid whitespace in plots
        x_max = bin_edges[-2] + width/2
        x_min = bin_edges[0] + width/2

        global_x_max = max(x_max, global_x_max)
        if global_x_min is None or x_min < global_x_min:
            global_x_min = x_min

    ax.set_xlim(global_x_min, global_x_max)
    ax.set_ylabel('New subscriptions [1/day]')
    if title:
        ax.set_title(title)
    if not ymax:
        # Always leave significant 5% for improvement ;-)
        ymax = global_y_max * 1.05
    ax.set_ylim(0, ymax)

    # set x-ticks in date
    # see: http://matplotlib.sourceforge.net/examples/api/date_demo.html
    ax.xaxis.set_major_locator(YearLocator())
    ax.xaxis.set_major_formatter(DateFormatter('\n\n%Y'))
    ax.xaxis.set_minor_locator(MonthLocator(interval=2))
    ax.xaxis.set_minor_formatter(DateFormatter('%b'))
    # format the coords message box
    ax.format_xdata = DateFormatter('%Y-%m-%d')
    ax.grid(True)
    # pukes with old matplotlib
    #font = FontProperties()
    #font.set_size = 8
    pl.legend(loc='upper left', #prop=font,
              labelspacing=.2, borderaxespad=.2,
              handletextpad=.2, borderpad=.2)


if __name__ == '__main__':
    if not len(sys.argv) > 1:
        print 'Need output filename.'
        sys.exit(1)
    cfg_path="/home/neurodebian/neurodebian.git/neurodebian.cfg"
    #cfg_path="../neurodebian.cfg"
    cfg = SafeConfigParser()
    cfg.read(cfg_path)
    data = []
    for line in fileinput.FileInput(sys.argv[2:], openhook=fileinput.hook_compressed):
        date, list_, ip = line.split(';')
        try:
            suite, loc = list_.split('.')
        except ValueError:
            suite = list_
            loc = ''
        date = datetime.strptime(date, "%d %b %Y")
        data.append((ip.strip(), loc, suite, date2num(date)))
    data = np.array(data, dtype=dt)
    make_figure(data).savefig(sys.argv[1], bbox_inches='tight', dpi=60)