# churn.py - create a graph of revisions count grouped by template
#
# Copyright 2006 Josef "Jeff" Sipek <jeffpc@josefsipek.net>
# Copyright 2008 Alexander Solovyov <piranha@piranha.org.ua>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
'''command to show certain statistics about revision history'''

from mercurial.i18n import _
from mercurial import patch, cmdutil, util, templater
import sys
import time, datetime

def maketemplater(ui, repo, tmpl):
    tmpl = templater.parsestring(tmpl, quoted=False)
    try:
        t = cmdutil.changeset_templater(ui, repo, False, None, None, False)
    except SyntaxError, inst:
        raise util.Abort(inst.args[0])
    t.use_template(tmpl)
    return t

def changedlines(ui, repo, ctx1, ctx2, fns):
    lines = 0
    fmatch = cmdutil.match(repo, pats=fns)
    diff = ''.join(patch.diff(repo, ctx1.node(), ctx2.node(), fmatch))
    for l in diff.split('\n'):
        if (l.startswith("+") and not l.startswith("+++ ") or
            l.startswith("-") and not l.startswith("--- ")):
            lines += 1
    return lines

def countrate(ui, repo, amap, *pats, **opts):
    """Calculate stats"""
    if opts.get('dateformat'):
        def getkey(ctx):
            t, tz = ctx.date()
            date = datetime.datetime(*time.gmtime(float(t) - tz)[:6])
            return date.strftime(opts['dateformat'])
    else:
        tmpl = opts.get('template', '{author|email}')
        tmpl = maketemplater(ui, repo, tmpl)
        def getkey(ctx):
            ui.pushbuffer()
            tmpl.show(ctx)
            return ui.popbuffer()

    count = pct = 0
    rate = {}
    df = False
    if opts.get('date'):
        df = util.matchdate(opts['date'])

    get = util.cachefunc(lambda r: repo[r].changeset())
    changeiter, matchfn = cmdutil.walkchangerevs(ui, repo, pats, get, opts)
    for st, rev, fns in changeiter:
        if not st == 'add':
            continue
        if df and not df(get(rev)[2][0]): # doesn't match date format
            continue

        ctx = repo[rev]
        key = getkey(ctx)
        key = amap.get(key, key) # alias remap
        if opts.get('changesets'):
            rate[key] = rate.get(key, 0) + 1
        else:
            parents = ctx.parents()
            if len(parents) > 1:
                ui.note(_('Revision %d is a merge, ignoring...\n') % (rev,))
                continue

            ctx1 = parents[0]
            lines = changedlines(ui, repo, ctx1, ctx, fns)
            rate[key] = rate.get(key, 0) + lines

        if opts.get('progress'):
            count += 1
            newpct = int(100.0 * count / max(len(repo), 1))
            if pct < newpct:
                pct = newpct
                ui.write("\r" + _("generating stats: %d%%") % pct)
                sys.stdout.flush()

    if opts.get('progress'):
        ui.write("\r")
        sys.stdout.flush()

    return rate


def churn(ui, repo, *pats, **opts):
    '''graph count of revisions grouped by template

    Will graph count of changed lines or revisions grouped by template
    or alternatively by date, if dateformat is used. In this case it
    will override template.

    By default statistics are counted for number of changed lines.

    Examples:

      # display count of changed lines for every committer
      hg churn -t '{author|email}'

      # display daily activity graph
      hg churn -f '%H' -s -c

      # display activity of developers by month
      hg churn -f '%Y-%m' -s -c

      # display count of lines changed in every year
      hg churn -f '%Y' -s

    The map file format used to specify aliases is fairly simple:

    <alias email> <actual email>'''
    def pad(s, l):
        return (s + " " * l)[:l]

    amap = {}
    aliases = opts.get('aliases')
    if aliases:
        for l in open(aliases, "r"):
            l = l.strip()
            alias, actual = l.split()
            amap[alias] = actual

    rate = countrate(ui, repo, amap, *pats, **opts).items()
    if not rate:
        return

    sortfn = ((not opts.get('sort')) and (lambda a, b: cmp(b[1], a[1])) or None)
    rate.sort(sortfn)

    maxcount = float(max([v for k, v in rate]))
    maxname = max([len(k) for k, v in rate])

    ttywidth = util.termwidth()
    ui.debug(_("assuming %i character terminal\n") % ttywidth)
    width = ttywidth - maxname - 2 - 6 - 2 - 2

    for date, count in rate:
        print "%s %6d %s" % (pad(date, maxname), count,
                             "*" * int(count * width / maxcount))


cmdtable = {
    "churn":
        (churn,
         [('r', 'rev', [], _('count rate for the specified revision or range')),
          ('d', 'date', '', _('count rate for revisions matching date spec')),
          ('t', 'template', '{author|email}', _('template to group changesets')),
          ('f', 'dateformat', '',
              _('strftime-compatible format for grouping by date')),
          ('c', 'changesets', False, _('count rate by number of changesets')),
          ('s', 'sort', False, _('sort by key (default: sort by count)')),
          ('', 'aliases', '', _('file with email aliases')),
          ('', 'progress', None, _('show progress'))],
         _("hg churn [-d DATE] [-r REV] [--aliases FILE] [--progress] [FILE]")),
}