# -*- coding: utf-8 -*-
"""
    sphinx.ext.autosummary.generate
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Usable as a library or script to generate automatic RST source files for
    items referred to in autosummary:: directives.

    Each generated RST file contains a single auto*:: directive which
    extracts the docstring of the referred item.

    Example Makefile rule::

       generate:
               sphinx-autogen -o source/generated source/*.rst

    :copyright: Copyright 2007-2011 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

from __future__ import (absolute_import, division, print_function)

import optparse
import os
import pydoc
import re
import sys

from jinja2 import FileSystemLoader, TemplateNotFound
from jinja2.sandbox import SandboxedEnvironment
from sphinx.jinja2glue import BuiltinTemplateLoader
from sphinx.util.osutil import ensuredir
from sphinx.util.inspect import safe_getattr

from autosummary import get_documenter, import_by_name


def main(argv=sys.argv):
    usage = """%prog [OPTIONS] SOURCEFILE ..."""
    p = optparse.OptionParser(usage.strip())
    p.add_option("-o", "--output-dir", action="store", type="string",
                 dest="output_dir", default=None,
                 help="Directory to place all output in")
    p.add_option("-s", "--suffix", action="store", type="string",
                 dest="suffix", default="rst",
                 help="Default suffix for files (default: %default)")
    p.add_option("-t", "--templates", action="store", type="string",
                 dest="templates", default=None,
                 help="Custom template directory (default: %default)")
    options, args = p.parse_args(argv[1:])

    if len(args) < 1:
        p.error('no input files given')

    generate_autosummary_docs(args, options.output_dir,
                              "." + options.suffix,
                              template_dir=options.templates)


def _simple_info(msg):
    print(msg)


def _simple_warn(msg):
    print('WARNING: ' + msg, file=sys.stderr)

# -- Generating output --------------------------------------------------------


def generate_autosummary_docs(sources, output_dir=None, suffix='.rst',
                              warn=_simple_warn, info=_simple_info,
                              base_path=None, builder=None, template_dir=None):

    showed_sources = list(sorted(sources))
    if len(showed_sources) > 20:
        showed_sources = showed_sources[:10] + ['...'] + showed_sources[-10:]
    info('[autosummary] generating autosummary for: %s' %
         ', '.join(showed_sources))

    if output_dir:
        info('[autosummary] writing to %s' % output_dir)

    if base_path is not None:
        sources = [os.path.join(base_path, filename) for filename in sources]

    # create our own templating environment
    template_dirs = [os.path.join(os.path.dirname(__file__), 'templates')]
    if builder is not None:
        # allow the user to override the templates
        template_loader = BuiltinTemplateLoader()
        template_loader.init(builder, dirs=template_dirs)
    else:
        if template_dir:
            template_dirs.insert(0, template_dir)
        template_loader = FileSystemLoader(template_dirs)
    template_env = SandboxedEnvironment(loader=template_loader,
                                        extensions=["jinja2.ext.do"])

    # read
    items = find_autosummary_in_files(sources)

    # remove possible duplicates
    items = dict([(item, True) for item in items]).keys()

    # keep track of new files
    new_files = []

    # write
    for name, path, template_name in sorted(items):
        if path is None:
            # The corresponding autosummary:: directive did not have
            # a :toctree: option
            continue

        path = output_dir or os.path.abspath(path)
        ensuredir(path)

        try:
            name, obj, parent = import_by_name(name)
        except ImportError as e:
            warn('[autosummary] failed to import %r: %s' % (name, e))
            continue

        fn = os.path.join(path, name + suffix)

        # skip it if it exists
        if os.path.isfile(fn):
            continue

        new_files.append(fn)

        f = open(fn, 'w')

        try:
            doc = get_documenter(obj, parent)

            if template_name is not None:
                template = template_env.get_template(template_name)
            else:
                try:
                    template = template_env.get_template('autosummary/%s.rst'
                                                         % doc.objtype)
                except TemplateNotFound:
                    template = template_env.get_template(
                        'autosummary/base.rst')

            def get_members(obj, typ, include_public=[]):
                items = []
                for name in dir(obj):
                    try:
                        documenter = get_documenter(safe_getattr(obj, name),
                                                    obj)
                    except AttributeError:
                        continue
                    if documenter.objtype == typ:
                        items.append(name)
                # XXX: patch start!
                if typ in ('function', 'class', 'exception'):
                    items = [name for name in items
                             if getattr(obj, name).__module__ == obj.__name__]
                elif typ == 'attribute':
                    items = [name for name in items
                             if not hasattr(getattr(obj, name), '__call__')]

                public = [x for x in items
                          if not x.startswith('_') or x.endswith('__')]
                # XXX: patch end!
                return public, items

            ns = {}

            if doc.objtype == 'module':
                ns['members'] = dir(obj)
                ns['functions'], ns['all_functions'] = \
                                   get_members(obj, 'function')
                ns['classes'], ns['all_classes'] = \
                                 get_members(obj, 'class')
                ns['exceptions'], ns['all_exceptions'] = \
                                   get_members(obj, 'exception')
            elif doc.objtype == 'class':
                ns['members'] = dir(obj)
                ns['methods'], ns['all_methods'] = \
                                 get_members(obj, 'method', ['__init__'])
                ns['attributes'], ns['all_attributes'] = \
                                 get_members(obj, 'attribute')

            parts = name.split('.')
            if doc.objtype in ('method', 'attribute'):
                mod_name = '.'.join(parts[:-2])
                cls_name = parts[-2]
                obj_name = '.'.join(parts[-2:])
                ns['class'] = cls_name
            else:
                mod_name, obj_name = '.'.join(parts[:-1]), parts[-1]

            ns['fullname'] = name
            ns['module'] = mod_name
            ns['objname'] = obj_name
            ns['name'] = parts[-1]

            ns['objtype'] = doc.objtype
            ns['underline'] = len(name) * '='

            rendered = template.render(**ns)
            f.write(rendered)
        finally:
            f.close()

    # descend recursively to new files
    if new_files:
        generate_autosummary_docs(new_files, output_dir=output_dir,
                                  suffix=suffix, warn=warn, info=info,
                                  base_path=base_path, builder=builder,
                                  template_dir=template_dir)


# -- Finding documented entries in files --------------------------------------

def find_autosummary_in_files(filenames):
    """Find out what items are documented in source/*.rst.

    See `find_autosummary_in_lines`.
    """
    documented = []
    for filename in filenames:
        f = open(filename, 'r')
        lines = f.read().splitlines()
        documented.extend(find_autosummary_in_lines(lines, filename=filename))
        f.close()
    return documented


def find_autosummary_in_docstring(name, module=None, filename=None):
    """Find out what items are documented in the given object's docstring.

    See `find_autosummary_in_lines`.
    """
    try:
        real_name, obj, parent = import_by_name(name)
        lines = pydoc.getdoc(obj).splitlines()
        return find_autosummary_in_lines(lines, module=name, filename=filename)
    except AttributeError:
        pass
    except ImportError as e:
        print("Failed to import '%s': %s" % (name, e))
    return []


def find_autosummary_in_lines(lines, module=None, filename=None):
    """Find out what items appear in autosummary:: directives in the
    given lines.

    Returns a list of (name, toctree, template) where *name* is a name
    of an object and *toctree* the :toctree: path of the corresponding
    autosummary directive (relative to the root of the file name), and
    *template* the value of the :template: option. *toctree* and
    *template* ``None`` if the directive does not have the
    corresponding options set.
    """
    autosummary_re = re.compile(r'^(\s*)\.\.\s+autosummary::\s*')
    automodule_re = re.compile(
        r'^\s*\.\.\s+automodule::\s*([A-Za-z0-9_.]+)\s*$')
    module_re = re.compile(
        r'^\s*\.\.\s+(current)?module::\s*([a-zA-Z0-9_.]+)\s*$')
    autosummary_item_re = re.compile(r'^\s+(~?[_a-zA-Z][a-zA-Z0-9_.]*)\s*.*?')
    toctree_arg_re = re.compile(r'^\s+:toctree:\s*(.*?)\s*$')
    template_arg_re = re.compile(r'^\s+:template:\s*(.*?)\s*$')

    documented = []

    toctree = None
    template = None
    current_module = module
    in_autosummary = False
    base_indent = ""

    for line in lines:
        if in_autosummary:
            m = toctree_arg_re.match(line)
            if m:
                toctree = m.group(1)
                if filename:
                    toctree = os.path.join(os.path.dirname(filename),
                                           toctree)
                continue

            m = template_arg_re.match(line)
            if m:
                template = m.group(1).strip()
                continue

            if line.strip().startswith(':'):
                continue  # skip options

            m = autosummary_item_re.match(line)
            if m:
                name = m.group(1).strip()
                if name.startswith('~'):
                    name = name[1:]
                if current_module and \
                       not name.startswith(current_module + '.'):
                    name = "%s.%s" % (current_module, name)
                documented.append((name, toctree, template))
                continue

            if not line.strip() or line.startswith(base_indent + " "):
                continue

            in_autosummary = False

        m = autosummary_re.match(line)
        if m:
            in_autosummary = True
            base_indent = m.group(1)
            toctree = None
            template = None
            continue

        m = automodule_re.search(line)
        if m:
            current_module = m.group(1).strip()
            # recurse into the automodule docstring
            documented.extend(find_autosummary_in_docstring(
                current_module, filename=filename))
            continue

        m = module_re.match(line)
        if m:
            current_module = m.group(2)
            continue

    return documented


if __name__ == '__main__':
    main()
