# -*- coding: utf-8 -*-
#
# Copyright (C) 2007 Edgewall Software
# All rights reserved.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at http://babel.edgewall.org/wiki/License.
#
# This software consists of voluntary contributions made by many
# individuals. For the exact contribution history, see the revision
# history and logs, available at http://babel.edgewall.org/log/.

"""Frontends for the message extraction functionality."""

from distutils import log
from distutils.cmd import Command
from distutils.errors import DistutilsOptionError
from optparse import OptionParser
import os
import re
import sys

from babel import __version__ as VERSION
from babel.catalog.extract import extract_from_dir, DEFAULT_KEYWORDS, \
                                  DEFAULT_MAPPING
from babel.catalog.pofile import write_po

__all__ = ['extract_messages', 'main']
__docformat__ = 'restructuredtext en'


class extract_messages(Command):
    """Message extraction command for use in ``setup.py`` scripts.
    
    If correctly installed, this command is available to Setuptools-using
    setup scripts automatically. For projects using plain old ``distutils``,
    the command needs to be registered explicitly in ``setup.py``::
    
        from babel.catalog.frontend import extract_messages
    
        setup(
            ...
            cmdclass = {'extract_messages': extract_messages}
        )
    
    :see: `Integrating new distutils commands <http://docs.python.org/dist/node32.html>`_
    :see: `setuptools <http://peak.telecommunity.com/DevCenter/setuptools>`_
    """

    description = 'extract localizable strings from the project code'
    user_options = [
        ('charset=', None,
         'charset to use in the output file'),
        ('keywords=', 'k',
         'space-separated list of keywords to look for in addition to the '
         'defaults'),
        ('no-default-keywords', None,
         'do not include the default keywords'),
        ('mapping-file=', 'F',
         'path to the mapping configuration file'),
        ('no-location', None,
         'do not include location comments with filename and line number'),
        ('omit-header', None,
         'do not include msgid "" entry in header'),
        ('output-file=', 'o',
         'name of the output file'),
        ('width=', 'w',
         'set output line width (default 76)'),
        ('no-wrap', None,
         'do not break long message lines, longer than the output line width, '
         'into several lines')
    ]
    boolean_options = [
        'no-default-keywords', 'no-location', 'omit-header', 'no-wrap'
    ]

    def initialize_options(self):
        self.charset = 'utf-8'
        self.keywords = self._keywords = DEFAULT_KEYWORDS.copy()
        self.no_default_keywords = False
        self.mapping_file = None
        self.no_location = False
        self.omit_header = False
        self.output_file = None
        self.width = 76
        self.no_wrap = False

    def finalize_options(self):
        if self.no_default_keywords and not self.keywords:
            raise DistutilsOptionError('you must specify new keywords if you '
                                       'disable the default ones')
        if self.no_default_keywords:
            self._keywords = {}
        if isinstance(self.keywords, basestring):
            self._keywords.update(parse_keywords(self.keywords.split()))
        self.keywords = self._keywords

        if self.no_wrap and self.width:
            raise DistutilsOptionError("'--no-wrap' and '--width' are mutually"
                                       "exclusive")
        if self.no_wrap:
            self.width = None
        else:
            self.width = int(self.width)

    def run(self):
        if self.mapping_file:
            fileobj = open(self.mapping_file, 'U')
            try:
                method_map, options_map = parse_mapping(fileobj)
            finally:
                fileobj.close()
        else:
            method_map = DEFAULT_MAPPING
            options_map = {}

        outfile = open(self.output_file, 'w')
        try:
            def callback(filename, options):
                optstr = ''
                if options:
                    optstr = ' (%s)' % ', '.join(['%s="%s"' % (k, v) for k, v
                                                  in options.items()])
                log.info('extracting messages from %s%s' % (filename, optstr))

            messages = []
            extracted = extract_from_dir(method_map=method_map,
                                         options_map=options_map,
                                         keywords=self.keywords,
                                         callback=callback)
            for filename, lineno, funcname, message in extracted:
                filepath = os.path.normpath(filename)
                messages.append((filepath, lineno, funcname, message, None))

            log.info('writing PO file to %s' % self.output_file)
            write_po(outfile, messages, project=self.distribution.get_name(),
                     version=self.distribution.get_version(), width=self.width,
                     charset=self.charset, no_location=self.no_location,
                     omit_header=self.omit_header)
        finally:
            outfile.close()

def main(argv=sys.argv):
    """Command-line interface.
    
    This function provides a simple command-line interface to the message
    extraction and PO file generation functionality.
    
    :param argv: list of arguments passed on the command-line
    """
    parser = OptionParser(usage='%prog [options] dirname1 <dirname2> ...',
                          version='%%prog %s' % VERSION)
    parser.add_option('--charset', dest='charset', default='utf-8',
                      help='charset to use in the output')
    parser.add_option('-k', '--keyword', dest='keywords',
                      default=[], action='append',
                      help='keywords to look for in addition to the defaults. '
                           'You can specify multiple -k flags on the command '
                           'line.')
    parser.add_option('--no-default-keywords', dest='no_default_keywords',
                      action='store_true', default=False,
                      help="do not include the default keywords")
    parser.add_option('--mapping', '-F', dest='mapping_file',
                      help='path to the extraction mapping file')
    parser.add_option('--no-location', dest='no_location', default=False,
                      action='store_true',
                      help='do not include location comments with filename and '
                           'line number')
    parser.add_option('--omit-header', dest='omit_header', default=False,
                      action='store_true',
                      help='do not include msgid "" entry in header')
    parser.add_option('-o', '--output', dest='output',
                      help='path to the output POT file')
    parser.add_option('-w', '--width', dest='width', type='int',
                      help="set output line width (default 76)")
    parser.add_option('--no-wrap', dest='no_wrap', default=False,
                      action = 'store_true', help='do not break long message '
                      'lines, longer than the output line width, into several '
                      'lines')
    options, args = parser.parse_args(argv[1:])
    if not args:
        parser.error('incorrect number of arguments')

    if options.output not in (None, '-'):
        outfile = open(options.output, 'w')
    else:
        outfile = sys.stdout

    keywords = DEFAULT_KEYWORDS.copy()
    if options.no_default_keywords:
        if not options.keywords:
            parser.error('you must specify new keywords if you disable the '
                         'default ones')
        keywords = {}
    if options.keywords:
        keywords.update(parse_keywords(options.keywords))

    if options.mapping_file:
        fileobj = open(options.mapping_file, 'U')
        try:
            method_map, options_map = parse_mapping(fileobj)
        finally:
            fileobj.close()
    else:
        method_map = DEFAULT_MAPPING
        options_map = {}

    if options.width and options.no_wrap:
        parser.error("'--no-wrap' and '--width' are mutually exclusive.")
    elif not options.width and not options.no_wrap:
        options.width = 76
    elif not options.width and options.no_wrap:
        options.width = 0

    try:
        messages = []
        for dirname in args:
            if not os.path.isdir(dirname):
                parser.error('%r is not a directory' % dirname)
            extracted = extract_from_dir(dirname, method_map, options_map,
                                         keywords)
            for filename, lineno, funcname, message in extracted:
                filepath = os.path.normpath(os.path.join(dirname, filename))
                messages.append((filepath, lineno, funcname, message, None))
        write_po(outfile, messages, width=options.width,
                 charset=options.charset, no_location=options.no_location,
                 omit_header=options.omit_header)
    finally:
        if options.output:
            outfile.close()

def parse_mapping(fileobj):
    """Parse an extraction method mapping from a file-like object.
    
    >>> from StringIO import StringIO
    >>> buf = StringIO('''
    ... # Python source files
    ... python: foobar/**.py
    ... 
    ... # Genshi templates
    ... genshi: foobar/**/templates/**.html
    ...     include_attrs = 
    ... genshi: foobar/**/templates/**.txt
    ...     template_class = genshi.template.text.TextTemplate
    ...     encoding = latin-1
    ... ''')
    
    >>> method_map, options_map = parse_mapping(buf)
    
    >>> method_map['foobar/**.py']
    'python'
    >>> options_map['foobar/**.py']
    {}
    >>> method_map['foobar/**/templates/**.html']
    'genshi'
    >>> options_map['foobar/**/templates/**.html']['include_attrs']
    ''
    >>> method_map['foobar/**/templates/**.txt']
    'genshi'
    >>> options_map['foobar/**/templates/**.txt']['template_class']
    'genshi.template.text.TextTemplate'
    >>> options_map['foobar/**/templates/**.txt']['encoding']
    'latin-1'
    
    :param fileobj: a readable file-like object containing the configuration
                    text to parse
    :return: a `(method_map, options_map)` tuple
    :rtype: `tuple`
    :see: `extract_from_directory`
    """
    method_map = {}
    options_map = {}

    method = None
    for line in fileobj.readlines():
        if line.startswith('#'): # comment
            continue
        match = re.match('(\w+): (.+)', line)
        if match:
            method, pattern = match.group(1, 2)
            method_map[pattern] = method
            options_map[pattern] = {}
        elif method:
            match = re.match('\s+(\w+)\s*=\s*(.*)', line)
            if match:
                option, value = match.group(1, 2)
                options_map[pattern][option] = value.strip()

    return (method_map, options_map)

def parse_keywords(strings=[]):
    """Parse keywords specifications from the given list of strings.
    
    >>> kw = parse_keywords(['_', 'dgettext:2', 'dngettext:2,3'])
    >>> for keyword, indices in sorted(kw.items()):
    ...     print (keyword, indices)
    ('_', None)
    ('dgettext', (2,))
    ('dngettext', (2, 3))
    """
    keywords = {}
    for string in strings:
        if ':' in string:
            funcname, indices = string.split(':')
        else:
            funcname, indices = string, None
        if funcname not in keywords:
            if indices:
                indices = tuple([(int(x)) for x in indices.split(',')])
            keywords[funcname] = indices
    return keywords

if __name__ == '__main__':
    main()