# -*- coding: utf-8 -*-
"""
    sphinx.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>).

    :copyright: Copyright 2007-2011 by the Sphinx team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""
import os
import sys
import optparse
from os import path

# automodule options
OPTIONS = [
    'members',
    'undoc-members',
    # 'inherited-members', # disabled because there's a bug in sphinx
    'show-inheritance',
]

INITPY = '__init__.py'

def makename(package, module):
    """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):
    """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
        f = open(fname, 'w')
        try:
            f.write(text)
        finally:
            f.close()

def format_heading(level, text):
    """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):
    """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):
    """Build the text of the file and write the file."""
    text = format_heading(1, '%s Module' % module)
    #text += format_heading(2, ':mod:`%s` Module' % module)
    text += format_directive(module, package)
    write_file(makename(package, module), text, opts)

def create_package_file(root, master_package, subroot, py_files, opts, subs):
    """Build the text of the file and write the file."""
    package = path.split(root)[-1]
    text = format_heading(1, '%s Package' % package)
    # add each module in the package
    for py_file in py_files:
        if shall_skip(path.join(root, py_file)):
            continue
        is_package = py_file == INITPY
        py_file = path.splitext(py_file)[0]
        py_path = makename(subroot, py_file)
        if is_package:
            heading = ':mod:`%s` Package' % package
        else:
            heading = ':mod:`%s` Module' % py_file
        text += format_heading(2, heading)
        text += format_directive(is_package and subroot or py_path,
                                 master_package)
        text += '\n'

    # build a list of directories that are packages (they 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'

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

def create_modules_toc_file(master_package, modules, opts, name='modules'):
    """
    Create the module's index.
    """
    text = format_heading(1, '%s Modules' % opts.header)
    text += '.. toctree::\n'
    text += '   :maxdepth: %s\n\n' % opts.maxdepth

    modules.sort()
    prev_module = ''
    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):
    """
    Check if we want to skip this module.
    """
    # skip it, if there is nothing (or just \n or \r\n) in the file
    return path.getsize(module) < 3

def recurse_tree(rootpath, excludes, opts):
    """
    Look for every file in the directory tree and create the corresponding
    ReST files.
    """
    # check if the base directory is a package and get is name
    if INITPY in os.listdir(rootpath):
        package_name = path.abspath(rootpath).split(path.sep)[-1]
    else:
        package_name = None

    toc = []
    tree = os.walk(rootpath, False)
    for root, subs, files in tree:
        # keep only the Python script files
        py_files =  sorted([f for f in files if path.splitext(f)[1] == '.py'])
        if INITPY in py_files:
            py_files.remove(INITPY)
            py_files.insert(0, INITPY)
        # remove hidden ('.') and private ('_') directories
        subs = sorted([sub for sub in subs if sub[0] not in ['.', '_']])
        # check if there are valid files to process
        # TODO: could add check for windows hidden files
        if "/." in root or "/_" in root \
               or not py_files \
               or is_excluded(root, excludes):
            continue
        if INITPY in py_files:
            # we are in package ...
            if (# ... with subpackage(s)
                subs
                or
                # ... with some module(s)
                len(py_files) > 1
                or
                # ... with a not-to-be-skipped INITPY file
                not shall_skip(path.join(root, INITPY))
               ):
                subroot = root[len(rootpath):].lstrip(path.sep).\
                          replace(path.sep, '.')
                create_package_file(root, package_name, subroot,
                                    py_files, opts, subs)
                toc.append(makename(package_name, subroot))
        elif root == rootpath:
            # if we are at the root level, we don't require it to be a package
            for py_file in py_files:
                if not shall_skip(path.join(rootpath, py_file)):
                    module = path.splitext(py_file)[0]
                    create_module_file(package_name, module, opts)
                    toc.append(makename(package_name, module))

    # create the module's index
    if not opts.notoc:
        create_modules_toc_file(package_name, toc, opts)

def normalize_excludes(rootpath, excludes):
    """
    Normalize the excluded directory list:
    * must be either an absolute path or start with rootpath,
    * otherwise it is joined with rootpath
    * with trailing slash
    """
    sep = path.sep
    f_excludes = []
    for exclude in excludes:
        if not path.isabs(exclude) and not exclude.startswith(rootpath):
            exclude = path.join(rootpath, exclude)
        if not exclude.endswith(sep):
            exclude += sep
        f_excludes.append(exclude)
    return f_excludes

def is_excluded(root, excludes):
    """
    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".
    """
    sep = path.sep
    if not root.endswith(sep):
        root += sep
    for exclude in excludes:
        if root.startswith(exclude):
            return True
    return False

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

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

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 all the files')
    parser.add_option('-n', '--dry-run', action='store_true', dest='dryrun',
                      help='Run the script without creating the files')
    parser.add_option('-T', '--no-toc', action='store_true', dest='notoc',
                      help='Don\'t create the table of contents file')
    parser.add_option('-H', '--doc-header', action='store', dest='header',
                      help='Documentation Header (default: Project)',
                      default='Project')
    parser.add_option('-s', '--suffix', action='store', dest='suffix',
                      help='file suffix (default: rst)', default='rst')

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

    if not args:
        parser.error('A package path is required.')
    if not opts.destdir:
        parser.error('An output directory is required.')
    rootpath, excludes = args[0], args[1:]
    if not path.isdir(rootpath):
        print >>sys.stderr, '%s is not a directory.' % rootpath
        sys.exit(1)
    if not path.isdir(opts.destdir):
        print '%s is not a valid output directory.' % opts.destdir
        sys.exit(1)
    excludes = normalize_excludes(rootpath, excludes)
    recurse_tree(rootpath, excludes, opts)