#!/usr/bin/python3
# -*- coding: utf-8 -*-
# Copyright 2012 T.C. Hollingsworth <tchollingsworth@gmail.com>
# Copyright 2017 Tomas Tomecek <ttomecek@redhat.com>
# Copyright 2019 Jan Staněk <jstanek@redhat.com>
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to
# deal in the Software without restriction, including without limitation the
# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.

"""Automatic provides generator for Node.js libraries.

Metadata taken from package.json.  See `man npm-json` for details.
"""

from __future__ import print_function, with_statement

import json
import os
import sys
from itertools import chain, groupby

DEPENDENCY_TEMPLATE = "npm(%(name)s) = %(version)s"
BUNDLED_TEMPLATE = "bundled(nodejs-%(name)s) = %(version)s"
NODE_MODULES = {"node_modules", "node_modules_prod"}


class PrivatePackage(RuntimeError):
    """Private package metadata that should not be listed."""


#: Something is wrong with the ``package.json`` file
_INVALID_METADATA_FILE = (IOError, PrivatePackage, KeyError)


def format_metadata(metadata, bundled=False):
    """Format ``package.json``-like metadata into RPM dependency.

    Arguments:
        metadata (dict): Package metadata, presumably read from ``package.json``.
        bundled (bool): Should the bundled dependency format be used?

    Returns:
        str: RPM dependency (i.e. ``npm(example) = 1.0.0``)

    Raises:
        KeyError: Expected key (i.e. ``name``, ``version``) missing in metadata.
        PrivatePackage: The metadata indicate private (unlisted) package.
    """

    # Skip private packages
    if metadata.get("private", False):
        raise PrivatePackage(metadata)

    template = BUNDLED_TEMPLATE if bundled else DEPENDENCY_TEMPLATE
    return template % metadata


def generate_dependencies(module_path, module_dir_set=NODE_MODULES):
    """Generate RPM dependency for a module and all it's dependencies.

    Arguments:
        module_path (str): Path to a module directory or it's ``package.json``
        module_dir_set (set): Base names of directories to look into
            for bundled dependencies.

    Yields:
        str: RPM dependency for the module and each of it's (public) bundled dependencies.

    Raises:
        ValueError: module_path is not valid module or ``package.json`` file
    """

    # Determine paths to root module directory and package.json
    if os.path.isdir(module_path):
        root_dir = module_path
    elif os.path.basename(module_path) == "package.json":
        root_dir = os.path.dirname(module_path)
    else:  # Invalid metadata path
        raise ValueError("Invalid module path '%s'" % module_path)

    for dir_path, subdir_list, file_list in os.walk(root_dir):
        # We are only interested in directories that contain package.json
        if "package.json" not in file_list:
            continue

        # Read and format metadata
        metadata_path = os.path.join(dir_path, "package.json")
        bundled = dir_path != root_dir
        try:
            with open(metadata_path, mode="r") as metadata_file:
                metadata = json.load(metadata_file)
            yield format_metadata(metadata, bundled=bundled)
        except _INVALID_METADATA_FILE:
            pass  # Ignore

        # Only visit subdirectories in module_dir_set
        subdir_list[:] = list(module_dir_set & set(subdir_list))


if __name__ == "__main__":
    module_paths = (path.strip() for path in sys.stdin)
    provides = chain.from_iterable(generate_dependencies(m) for m in module_paths)

    # sort|uniq
    for provide, __ in groupby(sorted(provides)):
        print(provide)