#!/usr/bin/env python2

# $Id$
# Author: David Goodger <goodger@python.org>
# Copyright: This module has been placed in the public domain.

"""
Generates .html from all the .txt files in a directory.

Ordinary .txt files are understood to be standalone reStructuredText.
Files named ``pep-*.txt`` are interpreted as reStructuredText PEPs.
"""
# Once PySource is here, build .html from .py as well.

__docformat__ = 'reStructuredText'


try:
    import locale
    locale.setlocale(locale.LC_ALL, '')
except:
    pass

import sys
import os
import os.path
import copy
from fnmatch import fnmatch
import docutils
from docutils import ApplicationError
from docutils import core, frontend, utils
from docutils.utils.error_reporting import ErrorOutput, ErrorString
from docutils.parsers import rst
from docutils.readers import standalone, pep
from docutils.writers import html5_polyglot, pep_html


usage = '%prog [options] [<directory> ...]'
description = ('Generates .html from all the reStructuredText .txt files '
               '(including PEPs) in each <directory> '
               '(default is the current directory).')


class SettingsSpec(docutils.SettingsSpec):

    """
    Runtime settings & command-line options for the front end.
    """

    prune_default = ['.hg', '.bzr', '.git', '.svn', 'CVS']

    # Can't be included in OptionParser below because we don't want to
    # override the base class.
    settings_spec = (
        'Build-HTML Options',
        None,
        (('Recursively scan subdirectories for files to process.  This is '
          'the default.',
          ['--recurse'],
          {'action': 'store_true', 'default': 1,
           'validator': frontend.validate_boolean}),
         ('Do not scan subdirectories for files to process.',
          ['--local'], {'dest': 'recurse', 'action': 'store_false'}),
         ('Do not process files in <directory> (shell globbing patterns, '
          'separated by colons).  This option may be used '
          'more than once to specify multiple directories.  Default: "%s".'
          % ':'.join(prune_default),
          ['--prune'],
          {'metavar': '<directory>', 'action': 'append',
           'validator': frontend.validate_colon_separated_string_list,
           'default': prune_default,}),
         ('Recursively ignore files matching any of the given '
          'wildcard (shell globbing) patterns (separated by colons).',
          ['--ignore'],
          {'metavar': '<patterns>', 'action': 'append',
           'default': ['.git', '.hg', '.svn'],
           'validator': frontend.validate_colon_separated_string_list}),
         ('Work silently (no progress messages).  Independent of "--quiet".',
          ['--silent'],
          {'action': 'store_true', 'validator': frontend.validate_boolean}),
         ('Do not process files, show files that would be processed.',
          ['--dry-run'],
          {'action': 'store_true', 'validator': frontend.validate_boolean}),))

    relative_path_settings = ('prune',)
    config_section = 'buildhtml application'
    config_section_dependencies = ('applications',)


class OptionParser(frontend.OptionParser):

    """
    Command-line option processing for the ``buildhtml.py`` front end.
    """

    def check_values(self, values, args):
        frontend.OptionParser.check_values(self, values, args)
        values._source = None
        return values

    def check_args(self, args):
        source = destination = None
        if args:
            self.values._directories = args
        else:
            self.values._directories = [os.getcwd()]
        return source, destination


class Struct:

    """Stores data attributes for dotted-attribute access."""

    def __init__(self, **keywordargs):
        self.__dict__.update(keywordargs)


class Builder:

    def __init__(self):
        self.publishers = {
            '': Struct(components=(pep.Reader, rst.Parser, pep_html.Writer,
                                   SettingsSpec)),
            '.txt': Struct(components=(rst.Parser, standalone.Reader,
                                       html5_polyglot.Writer, SettingsSpec),
                           reader_name='standalone',
                           writer_name='html5'),
            'PEPs': Struct(components=(rst.Parser, pep.Reader,
                                       pep_html.Writer, SettingsSpec),
                           reader_name='pep',
                           writer_name='pep_html')}
        """Publisher-specific settings.  Key '' is for the front-end script
        itself.  ``self.publishers[''].components`` must contain a superset of
        all components used by individual publishers."""

        self.setup_publishers()

    def setup_publishers(self):
        """
        Manage configurations for individual publishers.

        Each publisher (combination of parser, reader, and writer) may have
        its own configuration defaults, which must be kept separate from those
        of the other publishers.  Setting defaults are combined with the
        config file settings and command-line options by
        `self.get_settings()`.
        """
        for name, publisher in self.publishers.items():
            option_parser = OptionParser(
                components=publisher.components, read_config_files=1,
                usage=usage, description=description)
            publisher.option_parser = option_parser
            publisher.setting_defaults = option_parser.get_default_values()
            frontend.make_paths_absolute(publisher.setting_defaults.__dict__,
                                         option_parser.relative_path_settings)
            publisher.config_settings = (
                option_parser.get_standard_config_settings())
        self.settings_spec = self.publishers[''].option_parser.parse_args(
            values=frontend.Values())   # no defaults; just the cmdline opts
        self.initial_settings = self.get_settings('')

    def get_settings(self, publisher_name, directory=None):
        """
        Return a settings object, from multiple sources.

        Copy the setting defaults, overlay the startup config file settings,
        then the local config file settings, then the command-line options.
        Assumes the current directory has been set.
        """
        publisher = self.publishers[publisher_name]
        settings = frontend.Values(publisher.setting_defaults.__dict__)
        settings.update(publisher.config_settings, publisher.option_parser)
        if directory:
            local_config = publisher.option_parser.get_config_file_settings(
                os.path.join(directory, 'docutils.conf'))
            frontend.make_paths_absolute(
                local_config, publisher.option_parser.relative_path_settings,
                directory)
            settings.update(local_config, publisher.option_parser)
        settings.update(self.settings_spec.__dict__, publisher.option_parser)
        return settings

    def run(self, directory=None, recurse=1):
        recurse = recurse and self.initial_settings.recurse
        if directory:
            self.directories = [directory]
        elif self.settings_spec._directories:
            self.directories = self.settings_spec._directories
        else:
            self.directories = [os.getcwd()]
        for directory in self.directories:
            for root, dirs, files in os.walk(directory):
                # os.walk by default this recurses down the tree,
                # influence by modifying dirs.
                if not recurse:
                    del dirs[:]
                self.visit(root, files, dirs)

    def visit(self, directory, names, subdirectories):
        settings = self.get_settings('', directory)
        errout = ErrorOutput(encoding=settings.error_encoding)
        if settings.prune and (os.path.abspath(directory) in settings.prune):
            errout.write('/// ...Skipping directory (pruned): %s\n' %
                         directory)
            sys.stderr.flush()
            del subdirectories[:]
            return
        if not self.initial_settings.silent:
            errout.write('/// Processing directory: %s\n' % directory)
            sys.stderr.flush()
        # settings.ignore grows many duplicate entries as we recurse
        # if we add patterns in config files or on the command line.
        for pattern in utils.uniq(settings.ignore):
            for i in range(len(names) - 1, -1, -1):
                if fnmatch(names[i], pattern):
                    # Modify in place!
                    del names[i]
        for name in names:
            if name.endswith('.txt'):
                self.process_txt(directory, name)

    def process_txt(self, directory, name):
        if name.startswith('pep-'):
            publisher = 'PEPs'
        else:
            publisher = '.txt'
        settings = self.get_settings(publisher, directory)
        errout = ErrorOutput(encoding=settings.error_encoding)
        pub_struct = self.publishers[publisher]
        settings._source = os.path.normpath(os.path.join(directory, name))
        settings._destination = settings._source[:-4]+'.html'
        if not self.initial_settings.silent:
            errout.write('    ::: Processing: %s\n' % name)
            sys.stderr.flush()
        try:
            if not settings.dry_run:
                core.publish_file(source_path=settings._source,
                              destination_path=settings._destination,
                              reader_name=pub_struct.reader_name,
                              parser_name='restructuredtext',
                              writer_name=pub_struct.writer_name,
                              settings=settings)
        except ApplicationError:
            error = sys.exc_info()[1] # get exception in Python <2.6 and 3.x
            errout.write('        %s\n' % ErrorString(error))


if __name__ == "__main__":
    Builder().run()
