# Print a man page from the help texts.


import argparse
import sys
import datetime


__all__ = ['get_parser']


# We could substitute the "" in .TH with the fedpkg version if we knew it
man_header = """\
.\" man page for fedpkg
.TH fedpkg 1 "%(today)s" "" "fedora\-packager"
.SH "NAME"
fedpkg \- Fedora Packaging utility
.SH "SYNOPSIS"
.B "fedpkg"
[
.I global_options
]
.I "command"
[
.I command_options
]
[
.I command_arguments
]
.br
.B "fedpkg"
.B "help"
.br
.B "fedpkg"
.I "command"
.B "\-\-help"
.SH "DESCRIPTION"
.B "fedpkg"
is a script to interact with the Fedora Packaging system.
"""

man_footer = """\
.SH "SEE ALSO"
.UR "https://fedorahosted.org/fedora\-packager/"
.BR "https://fedorahosted.org/fedora\-packager/"
"""

class ManFormatter(object):

    def __init__(self, man):
        self.man = man

    def write(self, data):
        #print "MF:", repr(data)
        for line in data.split('\n'):
            #print 'MFL:', line
            self.man.write('  %s\n' % line)


def usage_clean(s):
    if s.startswith('usage: '):
        return s.replace('usage: ', '', 1)
    else:
        return s


def man_constants():
    """Global constants for man file templates"""
    today = datetime.date.today()
    today_manstr = today.strftime('%Y\-%m\-%d')
    return {'today': today_manstr}


def fedpkg_command(args):
    man_file = args.outfile

    # Not nice, but redirects any print statement output to stderr
    sys.stdout = sys.stderr

    mf = ManFormatter(man_file)

    subparsers = args.subparsers

    #print dir(subparsers)
    # subparsers.print_help()

    choices = subparsers.choices
    k = choices.keys()
    k.sort()

    man_file.write(man_header % man_constants())

    man_file.write('.SH "COMMAND OVERVIEW"\n')

    help_texts = {}
    for pa in subparsers._choices_actions:
        help_texts[pa.dest] = getattr(pa, 'help', None)

    for command in k:
        parser = choices[command]
        if not parser.add_help:
            continue
        usage = parser.format_usage()
        usage = usage_clean(usage)
        usage = ''.join(usage.split('\n'))
        usage = ' '.join(usage.split())
        if help_texts[command]:
            man_file.write('.TP\n.B "%s"\n%s\n' % (usage, help_texts[command]))
        else:
            man_file.write('.TP\n.B "%s"\n' % (usage))

    man_file.write('.SH "COMMAND REFERENCE"\n')
    for command in k:
        parser = choices[command]
        if not parser.add_help:
            continue

        #print
        #print "####", command, "####"
        man_file.write('.SS "%s"\n' % parser.prog)

        help = help_texts[command]
        if help and not parser.description:
            if not help.endswith('.'): help = "%s." % help
            parser.description = help
        #print parser
        formatter = parser.formatter_class(parser.prog)
        h = parser.format_help()
        mf.write(h)

    man_file.write(man_footer)


def add_parser(subparsers):

    descr = """\
Generate a basic fedpkg(1) man page from the command line argument
help text and descriptions.
"""

    sp = subparsers.add_parser('man-page',
                               help = 'Generate a fedpkg(1) man page',
                               description = descr)
    sp.add_argument('-o', '--output',
                    dest='outfile', nargs='?',
                    type=argparse.FileType('w'), default=sys.stdout,
                    help="File to write the man page to. Default is stdout.")
    sp.set_defaults(command = fedpkg_command)
    return sp