# -*- coding: utf-8 -*-
"""
    better apidoc
    ~~~~~~~~~~~~~

    Parses a directory tree looking for Python modules and packages and creates
    ReST files appropriately to create code documentation with Sphinx.  It also
    creates a modules index (named modules.<suffix>).

    This is derived from the "sphinx-apidoc" script, which is:
    Copyright 2007-2016 by the Sphinx team
    http://www.sphinx-doc.org

    It extends "sphinx-apidoc" by the --template / -t option, which allows to
    render the output ReST files based on arbitrary Jinja templates.

    :copyright: Copyright 2017 by Michael Goerz
    :license: BSD, see LICENSE for details.
"""
from __future__ import print_function

import os
import sys
import importlib
import optparse
from os import path
from six import binary_type
from fnmatch import fnmatch

from jinja2 import FileSystemLoader, TemplateNotFound
from jinja2.sandbox import SandboxedEnvironment

from sphinx.util.osutil import FileAvoidWrite, walk
#from sphinx import __display_version__
from sphinx.quickstart import EXTENSIONS
from sphinx.ext.autosummary import get_documenter
from sphinx.util.inspect import safe_getattr

# Add documenters to AutoDirective registry
from sphinx.ext.autodoc import add_documenter, \
    ModuleDocumenter, ClassDocumenter, ExceptionDocumenter, DataDocumenter, \
    FunctionDocumenter, MethodDocumenter, AttributeDocumenter, \
    InstanceAttributeDocumenter
add_documenter(ModuleDocumenter)
add_documenter(ClassDocumenter)
add_documenter(ExceptionDocumenter)
add_documenter(DataDocumenter)
add_documenter(FunctionDocumenter)
add_documenter(MethodDocumenter)
add_documenter(AttributeDocumenter)
add_documenter(InstanceAttributeDocumenter)

__version__ = '0.1.1'
__display_version__ = __version__

if False:
    # For type annotation
    from typing import Any, List, Tuple  # NOQA

# automodule options
if 'SPHINX_APIDOC_OPTIONS' in os.environ:
    OPTIONS = os.environ['SPHINX_APIDOC_OPTIONS'].split(',')
else:
    OPTIONS = [
        'members',
        'undoc-members',
        # 'inherited-members', # disabled because there's a bug in sphinx
        'show-inheritance',
    ]

INITPY = '__init__.py'
PY_SUFFIXES = set(['.py', '.pyx'])


def _warn(msg):
    # type: (unicode) -> None
    print('WARNING: ' + msg, file=sys.stderr)


def makename(package, module):
    # type: (unicode, unicode) -> unicode
    """Join package and module with a dot."""
    # Both package and module can be None/empty.
    if package:
        name = package
        if module:
            name += '.' + module
    else:
        name = module
    return name


def write_file(name, text, opts):
    # type: (unicode, unicode, Any) -> None
    """Write the output file for module/package <name>."""
    fname = path.join(opts.destdir, '%s.%s' % (name, opts.suffix))
    if opts.dryrun:
        print('Would create file %s.' % fname)
        return
    if not opts.force and path.isfile(fname):
        print('File %s already exists, skipping.' % fname)
    else:
        print('Creating file %s.' % fname)
        with FileAvoidWrite(fname) as f:
            f.write(text)


def format_heading(level, text):
    # type: (int, unicode) -> unicode
    """Create a heading of <level> [1, 2 or 3 supported]."""
    underlining = ['=', '-', '~', ][level - 1] * len(text)
    return '%s\n%s\n\n' % (text, underlining)


def format_directive(module, package=None):
    # type: (unicode, unicode) -> unicode
    """Create the automodule directive and add the options."""
    directive = '.. automodule:: %s\n' % makename(package, module)
    for option in OPTIONS:
        directive += '    :%s:\n' % option
    return directive


def create_module_file(package, module, opts):
    # type: (unicode, unicode, Any) -> None
    """Generate RST for a top-level module (i.e., not part of a package)"""
    if not opts.noheadings:
        text = format_heading(1, '%s module' % module)
    else:
        text = ''
    # text += format_heading(2, ':mod:`%s` Module' % module)
    text += format_directive(module, package)

    if opts.templates:
        template_loader = FileSystemLoader(opts.templates)
        template_env = SandboxedEnvironment(loader=template_loader)
        try:
            mod_ns = _get_mod_ns(
                name=module, fullname=module,
                includeprivate=opts.includeprivate)
            template = template_env.get_template('module.rst')
            text = template.render(**mod_ns)
        except ImportError as e:
            _warn('failed to import %r: %s' % (module, e))
    write_file(makename(package, module), text, opts)


def _get_members(
        obj, typ=None, include_imported=False, as_refs=False, in__all__=False):
    """Get (filtered) public/total members of the module or package `obj`.

    Args:
        obj: object resulting from importing a module or package
        typ: filter on members. If None, include all members. If one of
            'function', 'class', 'exception', 'data', only include members of
            the matching type
        include_imported: If True, also include members that are imports
        as_refs: If True, return ReST-formatted reference strings for all
            members, instead of just their names. In combinations with
            `include_imported` or `in__all__`, these link to the original
            location where the member is defined
        in__all__: If True, return only members that are in ``obj.__all__``

    Returns:
        lists `public` and `items`. The lists contains the public and private +
        public  members, as strings.
    """
    roles = {'function': 'func', 'module': 'mod', 'class': 'class',
             'exception': 'exc', 'data': 'data'}
    # not included, because they cannot occur at modul level:
    #   'method': 'meth', 'attribute': 'attr', 'instanceattribute': 'attr'

    def check_typ(typ, obj, value):
        """Check if obj.value is of the desired typ"""
        documenter = get_documenter(value, obj)
        if typ is None:
            return True
        if typ == getattr(documenter, 'objtype', None):
            return True
        if hasattr(documenter, 'directivetype'):
            return roles[typ] == getattr(documenter, 'directivetype')

    if typ is not None and typ not in roles:
        raise ValueError("typ must be None or one of %s"
                         % str(list(roles.keys())))
    items = []
    public = []
    all_list = getattr(obj, '__all__', [])
    for name in dir(obj):
        try:
            value = safe_getattr(obj, name)
        except AttributeError:
            continue
        if check_typ(typ, obj, value):
            if in__all__ and name not in all_list:
                continue
            if (include_imported or
                    getattr(value, '__module__', None) == obj.__name__):
                if as_refs:
                    documenter = get_documenter(value, obj)
                    role = roles.get(documenter.objtype, 'obj')
                    ref = _get_member_ref_str(name, obj=value, role=role)
                    items.append(ref)
                    if not name.startswith('_'):
                        public.append(ref)
                else:
                    items.append(name)
                    if not name.startswith('_'):
                        public.append(name)
    return public, items


def _get_member_ref_str(name, obj, role='obj'):
    """generate a ReST-formmated reference link to the given `obj` of type
    `role`, using `name` as the link text"""
    if hasattr(obj, '__name__'):
        try:
            ref = obj.__module__ + '.' + obj.__name__
        except AttributeError:
            ref = obj.__name__
        except TypeError:  # e.g. obj.__name__ is None
            ref = name
    else:
        ref = name
    return ":%s:`%s <%s>`" % (role, name, ref)


def _get_mod_ns(name, fullname, includeprivate):
    """Return the template context of module identified by `fullname` as a
    dict"""
    ns = {  # template variables
        'name': name, 'fullname': fullname, 'members': [], 'functions': [],
        'classes': [], 'exceptions': [], 'subpackages': [], 'submodules': [],
        'all_refs': [], 'members_imports': [], 'members_imports_refs': [],
        'data': []}
    p = 0
    if includeprivate:
        p = 1
    obj = importlib.import_module(fullname)
    ns['members'] = _get_members(obj)[p]
    ns['functions'] = _get_members(obj, typ='function')[p]
    ns['classes'] = _get_members(obj, typ='class')[p]
    ns['exceptions'] = _get_members(obj, typ='exception')[p]
    ns['all_refs'] = _get_members(obj, include_imported=True, in__all__=True, as_refs=True)[p]
    ns['members_imports'] = _get_members(obj, include_imported=True)[p]
    ns['members_imports_refs'] = _get_members(obj, include_imported=True, as_refs=True)[p]
    ns['data'] = _get_members(obj, typ='data')[p]
    return ns


def create_package_file(root, master_package, subroot, py_files, opts, subs, is_namespace):
    # type: (unicode, unicode, unicode, List[unicode], Any, List[unicode], bool) -> None
    """Build the text of the file and write the file."""

    use_templates = False
    if opts.templates:
        use_templates = True
        template_loader = FileSystemLoader(opts.templates)
        template_env = SandboxedEnvironment(loader=template_loader)

    fullname = makename(master_package, subroot)

    text = format_heading(
        1, ('%s package' if not is_namespace else "%s namespace") % fullname)

    if opts.modulefirst and not is_namespace:
        text += format_directive(subroot, master_package)
        text += '\n'

    # build a list of directories that are szvpackages (contain an INITPY file)
    subs = [sub for sub in subs if path.isfile(path.join(root, sub, INITPY))]
    # if there are some package directories, add a TOC for theses subpackages
    if subs:
        text += format_heading(2, 'Subpackages')
        text += '.. toctree::\n\n'
        for sub in subs:
            text += '    %s.%s\n' % (makename(master_package, subroot), sub)
        text += '\n'

    submods = [path.splitext(sub)[0] for sub in py_files
               if not shall_skip(path.join(root, sub), opts) and
               sub != INITPY]

    if use_templates:
        try:
            package_ns = _get_mod_ns(name=subroot, fullname=fullname,
                                     includeprivate=opts.includeprivate)
            package_ns['subpackages'] = subs
            package_ns['submodules'] = submods
        except ImportError as e:
            _warn('failed to import %r: %s' % (fullname, e))

    if submods:
        text += format_heading(2, 'Submodules')
        if opts.separatemodules:
            text += '.. toctree::\n\n'
            for submod in submods:
                modfile = makename(master_package, makename(subroot, submod))
                text += '   %s\n' % modfile

                # generate separate file for this module
                if not opts.noheadings:
                    filetext = format_heading(1, '%s module' % modfile)
                else:
                    filetext = ''
                filetext += format_directive(makename(subroot, submod),
                                             master_package)
                if use_templates:
                    try:
                        mod_ns = _get_mod_ns(
                            name=submod, fullname=modfile,
                            includeprivate=opts.includeprivate)
                        template = template_env.get_template('module.rst')
                        filetext = template.render(**mod_ns)
                    except ImportError as e:
                        _warn('failed to import %r: %s' % (modfile, e))
                write_file(modfile, filetext, opts)
        else:
            for submod in submods:
                modfile = makename(master_package, makename(subroot, submod))
                if not opts.noheadings:
                    text += format_heading(2, '%s module' % modfile)
                text += format_directive(makename(subroot, submod),
                                         master_package)
                text += '\n'
        text += '\n'

    if use_templates:
        template = template_env.get_template('package.rst')
        text = template.render(**package_ns)
    else:
        if not opts.modulefirst and not is_namespace:
            text += format_heading(2, 'Module contents')
            text += format_directive(subroot, master_package)

    write_file(makename(master_package, subroot), text, opts)


def create_modules_toc_file(modules, opts, name='modules'):
    # type: (List[unicode], Any, unicode) -> None
    """Create the module's index."""
    text = format_heading(1, '%s' % opts.header)
    text += '.. toctree::\n'
    text += '   :maxdepth: %s\n\n' % opts.maxdepth

    modules.sort()
    prev_module = ''  # type: unicode
    for module in modules:
        # look if the module is a subpackage and, if yes, ignore it
        if module.startswith(prev_module + '.'):
            continue
        prev_module = module
        text += '   %s\n' % module

    write_file(name, text, opts)


def shall_skip(module, opts):
    # type: (unicode, Any) -> bool
    """Check if we want to skip this module."""
    # skip if the file doesn't exist and not using implicit namespaces
    if not opts.implicit_namespaces and not path.exists(module):
        return True

    # skip it if there is nothing (or just \n or \r\n) in the file
    if path.exists(module) and path.getsize(module) <= 2:
        return True

    # skip if it has a "private" name and this is selected
    filename = path.basename(module)
    if filename != '__init__.py' and filename.startswith('_') and \
       not opts.includeprivate:
        return True
    return False


def recurse_tree(rootpath, excludes, opts):
    # type: (unicode, List[unicode], Any) -> List[unicode]
    """
    Look for every file in the directory tree and create the corresponding
    ReST files.
    """
    # check if the base directory is a package and get its name
    if INITPY in os.listdir(rootpath):
        root_package = rootpath.split(path.sep)[-1]
    else:
        # otherwise, the base is a directory with packages
        root_package = None

    toplevels = []
    followlinks = getattr(opts, 'followlinks', False)
    includeprivate = getattr(opts, 'includeprivate', False)
    implicit_namespaces = getattr(opts, 'implicit_namespaces', False)
    for root, subs, files in walk(rootpath, followlinks=followlinks):
        # document only Python module files (that aren't excluded)
        py_files = sorted(f for f in files
                          if path.splitext(f)[1] in PY_SUFFIXES and
                          not is_excluded(path.join(root, f), excludes))
        is_pkg = INITPY in py_files
        is_namespace = INITPY not in py_files and implicit_namespaces
        if is_pkg:
            py_files.remove(INITPY)
            py_files.insert(0, INITPY)
        elif root != rootpath:
            # only accept non-package at toplevel unless using implicit namespaces
            if not implicit_namespaces:
                del subs[:]
                continue
        # remove hidden ('.') and private ('_') directories, as well as
        # excluded dirs
        if includeprivate:
            exclude_prefixes = ('.',)  # type: Tuple[unicode, ...]
        else:
            exclude_prefixes = ('.', '_')
        subs[:] = sorted(sub for sub in subs if not sub.startswith(exclude_prefixes) and
                         not is_excluded(path.join(root, sub), excludes))

        if is_pkg or is_namespace:
            # we are in a package with something to document
            if subs or len(py_files) > 1 or not shall_skip(path.join(root, INITPY), opts):
                subpackage = root[len(rootpath):].lstrip(path.sep).\
                    replace(path.sep, '.')
                # if this is not a namespace or
                # a namespace and there is something there to document
                if not is_namespace or len(py_files) > 0:
                    create_package_file(root, root_package, subpackage,
                                        py_files, opts, subs, is_namespace)
                    toplevels.append(makename(root_package, subpackage))
        else:
            # if we are at the root level, we don't require it to be a package
            assert root == rootpath and root_package is None
            if opts.templates:
                sys.path.insert(0, rootpath)
            for py_file in py_files:
                if not shall_skip(path.join(rootpath, py_file), opts):
                    module = path.splitext(py_file)[0]
                    create_module_file(root_package, module, opts)
                    toplevels.append(module)
            if opts.templates:
                sys.path.pop(0)

    return toplevels


def normalize_excludes(rootpath, excludes):
    # type: (unicode, List[unicode]) -> List[unicode]
    """Normalize the excluded directory list."""
    return [path.abspath(exclude) for exclude in excludes]


def is_excluded(root, excludes):
    # type: (unicode, List[unicode]) -> bool
    """Check if the directory is in the exclude list.

    Note: by having trailing slashes, we avoid common prefix issues, like
          e.g. an exlude "foo" also accidentally excluding "foobar".
    """
    for exclude in excludes:
        if fnmatch(root, exclude):
            return True
    return False


def main(argv=sys.argv):
    # type: (List[str]) -> int
    """Parse and check the command line arguments."""
    parser = optparse.OptionParser(
        usage="""\
usage: %prog [options] -o <output_path> <module_path> [exclude_pattern, ...]

Look recursively in <module_path> for Python modules and packages and create
one reST file with automodule directives per package in the <output_path>.

The <exclude_pattern>s can be file and/or directory patterns that will be
excluded from generation.

Note: By default this script will not overwrite already created files.""")

    parser.add_option('-o', '--output-dir', action='store', dest='destdir',
                      help='Directory to place all output', default='')
    parser.add_option('-d', '--maxdepth', action='store', dest='maxdepth',
                      help='Maximum depth of submodules to show in the TOC '
                      '(default: 4)', type='int', default=4)
    parser.add_option('-f', '--force', action='store_true', dest='force',
                      help='Overwrite existing files')
    parser.add_option('-l', '--follow-links', action='store_true',
                      dest='followlinks', default=False,
                      help='Follow symbolic links. Powerful when combined '
                      'with collective.recipe.omelette.')
    parser.add_option('-n', '--dry-run', action='store_true', dest='dryrun',
                      help='Run the script without creating files')
    parser.add_option('-e', '--separate', action='store_true',
                      dest='separatemodules',
                      help='Put documentation for each module on its own page')
    parser.add_option('-P', '--private', action='store_true',
                      dest='includeprivate',
                      help='Include "_private" modules')
    parser.add_option('-T', '--no-toc', action='store_true', dest='notoc',
                      help='Don\'t create a table of contents file')
    parser.add_option('-E', '--no-headings', action='store_true',
                      dest='noheadings',
                      help='Don\'t create headings for the module/package '
                           'packages (e.g. when the docstrings already contain '
                           'them). No effect in combination with -t')
    parser.add_option('-M', '--module-first', action='store_true',
                      dest='modulefirst',
                      help='Put module documentation before submodule '
                      'documentation (no effect in combination with -t)')
    parser.add_option('--implicit-namespaces', action='store_true',
                      dest='implicit_namespaces',
                      help='Interpret module paths according to PEP-0420 '
                           'implicit namespaces specification')
    parser.add_option('-s', '--suffix', action='store', dest='suffix',
                      help='file suffix (default: rst)', default='rst')
    parser.add_option('-F', '--full', action='store_true', dest='full',
                      help='Generate a full project with sphinx-quickstart')
    parser.add_option('-a', '--append-syspath', action='store_true',
                      dest='append_syspath',
                      help='Append module_path to sys.path, used when --full is given')
    parser.add_option("-t", "--templates", action="store", type="string",
                      dest="templates", default=None,
                      help="Custom template directory (default: %default). "
                      "Must contain template files package.rst and/or "
                      "module.rst")
    parser.add_option('-H', '--doc-project', action='store', dest='header',
                      help='Project name (default: root module name)')
    parser.add_option('-A', '--doc-author', action='store', dest='author',
                      type='str',
                      help='Project author(s), used when --full is given')
    parser.add_option('-V', '--doc-version', action='store', dest='version',
                      help='Project version, used when --full is given')
    parser.add_option('-R', '--doc-release', action='store', dest='release',
                      help='Project release, used when --full is given, '
                      'defaults to --doc-version')
    parser.add_option('--version', action='store_true', dest='show_version',
                      help='Show version information and exit')
    group = parser.add_option_group('Extension options')
    for ext in EXTENSIONS:
        group.add_option('--ext-' + ext, action='store_true',
                         dest='ext_' + ext, default=False,
                         help='enable %s extension' % ext)

    (opts, args) = parser.parse_args(argv[1:])

    if opts.show_version:
        #print('Sphinx (sphinx-apidoc) %s' % __display_version__)
        print('better-apidoc %s' % __display_version__)
        return 0

    if not args:
        parser.error('A package path is required.')

    rootpath, excludes = args[0], args[1:]
    if not opts.destdir:
        parser.error('An output directory is required.')
    if opts.header is None:
        opts.header = path.abspath(rootpath).split(path.sep)[-1]
    if opts.suffix.startswith('.'):
        opts.suffix = opts.suffix[1:]
    if not path.isdir(rootpath):
        print('%s is not a directory.' % rootpath, file=sys.stderr)
        sys.exit(1)
    if not path.isdir(opts.destdir):
        if not opts.dryrun:
            os.makedirs(opts.destdir)
    rootpath = path.abspath(rootpath)
    excludes = normalize_excludes(rootpath, excludes)
    try:
        modules = recurse_tree(rootpath, excludes, opts)
    except TemplateNotFound as e:
        print('Cannot find template in %s: %s' %
              (opts.templates, e), file=sys.stderr)
        sys.exit(1)

    if opts.full:
        raise NotImplementedError("--full not supported")
        # This would only make sense if this script was integrated in Sphinx
        from sphinx import quickstart as qs
        modules.sort()
        prev_module = ''  # type: unicode
        text = ''
        for module in modules:
            if module.startswith(prev_module + '.'):
                continue
            prev_module = module
            text += '   %s\n' % module
        d = dict(
            path = opts.destdir,
            sep = False,
            dot = '_',
            project = opts.header,
            author = opts.author or 'Author',
            version = opts.version or '',
            release = opts.release or opts.version or '',
            suffix = '.' + opts.suffix,
            master = 'index',
            epub = True,
            ext_autodoc = True,
            ext_viewcode = True,
            ext_todo = True,
            makefile = True,
            batchfile = True,
            mastertocmaxdepth = opts.maxdepth,
            mastertoctree = text,
            language = 'en',
            module_path = rootpath,
            append_syspath = opts.append_syspath,
        )
        enabled_exts = {'ext_' + ext: getattr(opts, 'ext_' + ext)
                        for ext in EXTENSIONS if getattr(opts, 'ext_' + ext)}
        d.update(enabled_exts)

        if isinstance(opts.header, binary_type):
            d['project'] = d['project'].decode('utf-8')
        if isinstance(opts.author, binary_type):
            d['author'] = d['author'].decode('utf-8')
        if isinstance(opts.version, binary_type):
            d['version'] = d['version'].decode('utf-8')
        if isinstance(opts.release, binary_type):
            d['release'] = d['release'].decode('utf-8')

        if not opts.dryrun:
            qs.generate(d, silent=True, overwrite=opts.force)
    elif not opts.notoc:
        create_modules_toc_file(modules, opts)
    return 0


# So program can be started with "python -m sphinx.apidoc ..."
#if __name__ == "__main__":
    #main()
