#!/usr/bin/env python2

"""

Consistent formatting of rst section titles

"""

import re

import subprocess

spaces = [

    (0, 1), # we assume this is a over-and-underlined header

    (2, 1),

    (1, 1),

    (1, 0),

    (1, 0),

    ]

# match on a header line underlined with one of the valid characters

headermatch = re.compile(r'''\n*(.+)\n([][!"#$%&'()*+,./:;<=>?@\\^_`{|}~-])\2{2,}\n+''', flags=re.MULTILINE)

def main():

    for fn in subprocess.check_output(['hg', 'loc', 'set:**.rst+kallithea/i18n/how_to']).splitlines():

        print 'processing %s:' % fn

        s = file(fn).read()

        # find levels and their styles

        lastpos = 0

        styles = []

        for markup in headermatch.findall(s):

            style = markup[1]

            if style in styles:

                stylepos = styles.index(style)

                if stylepos > lastpos + 1:

                    print 'bad style %r with level %s - was at %s' % (style, stylepos, lastpos)

            else:

                stylepos = len(styles)

                if stylepos > lastpos + 1:

                    print 'bad new style %r - expected %r' % (style, styles[lastpos + 1])

                else:

                    styles.append(style)

            lastpos = stylepos

        # remove superfluous spacing (may however be restored by header spacing)

        s = re.sub(r'''(\n\n)\n*''', r'\1', s, flags=re.MULTILINE)

        # rewrite header markup with correct style, length and spacing

        def subf(m):

            title, style = m.groups()

            level = styles.index(style)

            before, after = spaces[level]

            return '\n' * (before + 1) + title + '\n' + style * len(title) + '\n' * (after + 1)

        s = headermatch.sub(subf, s)

        # remove superfluous spacing when headers are adjacent

        s = re.sub(r'''(\n.+\n([][!"#$%&'()*+,./:;<=>?@\\^_`{|}~-])\2{2,}\n\n\n)\n*''', r'\1', s, flags=re.MULTILINE)

        # fix trailing space and spacing before link sections

        s = s.strip() + '\n'

        s = re.sub(r'''\n+((?:\.\. _[^\n]*\n)+)$''', r'\n\n\n\1', s)

        file(fn, 'w').write(s)

        print subprocess.check_output(['hg', 'diff', fn])

        print

if __name__ == '__main__':

    main()