#!/usr/bin/env python3

#

# generates Provides: bundled(npm(...)) = ... lines for each declared dependency and devDependency of package.json

#

import os

import sys

import json

import yaml

from packaging import version

def scan_package_json(package_dir):

    for root, dirs, files in os.walk(package_dir, topdown=True):

        dirs[:] = [d for d in dirs if d not in ["node_modules", "vendor"]]

        if "package.json" in files:

            yield os.path.join(root, "package.json")

def read_declared_pkgs(package_json_path):

    with open(package_json_path) as f:

        package_json = json.load(f)

        return list(package_json.get("dependencies", {}).keys()) + list(

            package_json.get("devDependencies", {}).keys()

        )

def read_installed_pkgs(yarn_lock_path):

    with open(yarn_lock_path) as f:

        lockfile = yaml.safe_load(f)

        for pkg_decl, meta in lockfile.items():

            for pkg in pkg_decl.split(", "):

                if ":" not in pkg:

                    continue

                pkg_name = pkg[: pkg.index("@", 1)]

                pkg_version = meta["version"]

                yield (pkg_name, pkg_version)

def list_provides(declared_pkgs, installed_pkgs):

    for declared_pkg in declared_pkgs:

        # there can be multiple versions installed of one package (transitive dependencies)

        # but rpm doesn't support Provides: with a single package and multiple versions

        # so let's declare the oldest version here

        versions = [

            version.parse(pkg_version)

            for pkg_name, pkg_version in installed_pkgs

            if pkg_name == declared_pkg

        ]

        if not versions:

            print(f"warning: {declared_pkg} missing in yarn.lock", file=sys.stderr)

            continue

        oldest_version = sorted(versions)[0]

        yield f"Provides: bundled(npm({declared_pkg})) = {oldest_version}"

if __name__ == "__main__":

    if len(sys.argv) != 2:

        print(f"usage: {sys.argv[0]} package-X.Y.Z/", file=sys.stdout)

        sys.exit(1)

    package_dir = sys.argv[1]

    declared_pkgs = set()

    for package_json_path in scan_package_json(package_dir):

        declared_pkgs.update(read_declared_pkgs(package_json_path))

    installed_pkgs = list(read_installed_pkgs(f"{package_dir}/yarn.lock"))

    provides = list_provides(declared_pkgs, installed_pkgs)

    for provide in sorted(provides):

        print(provide)