Gather details from installed distributions. Print distribution name,
    version, location, and installed files. Installed files requires a
    pip generated 'installed-files.txt' in the distributions '.egg-info'
    directory.

def search_packages_info(query):
    """
    Gather details from installed distributions. Print distribution name,
    version, location, and installed files. Installed files requires a
    pip generated 'installed-files.txt' in the distributions '.egg-info'
    directory.
    """
    installed = {}
    for p in pkg_resources.working_set:
        installed[canonicalize_name(p.project_name)] = p

    query_names = [canonicalize_name(name) for name in query]

    for dist in [installed[pkg] for pkg in query_names if pkg in installed]:
        package = {
            'name': dist.project_name,
            'version': dist.version,
            'location': dist.location,
            'requires': [dep.project_name for dep in dist.requires()],
        }
        file_list = None
        metadata = None
        if isinstance(dist, pkg_resources.DistInfoDistribution):
            # RECORDs should be part of .dist-info metadatas
            if dist.has_metadata('RECORD'):
                lines = dist.get_metadata_lines('RECORD')
                paths = [l.split(',')[0] for l in lines]
                paths = [os.path.join(dist.location, p) for p in paths]
                file_list = [os.path.relpath(p, dist.location) for p in paths]

            if dist.has_metadata('METADATA'):
                metadata = dist.get_metadata('METADATA')
        else:
            # Otherwise use pip's log for .egg-info's
            if dist.has_metadata('installed-files.txt'):
                paths = dist.get_metadata_lines('installed-files.txt')
                paths = [os.path.join(dist.egg_info, p) for p in paths]
                file_list = [os.path.relpath(p, dist.location) for p in paths]

            if dist.has_metadata('PKG-INFO'):
                metadata = dist.get_metadata('PKG-INFO')

        if dist.has_metadata('entry_points.txt'):
            entry_points = dist.get_metadata_lines('entry_points.txt')
            package['entry_points'] = entry_points

        if dist.has_metadata('INSTALLER'):
            for line in dist.get_metadata_lines('INSTALLER'):
                if line.strip():
                    package['installer'] = line.strip()
                    break

        # @todo: Should pkg_resources.Distribution have a
        # `get_pkg_info` method?
        feed_parser = FeedParser()
        feed_parser.feed(metadata)
        pkg_info_dict = feed_parser.close()
        for key in ('metadata-version', 'summary',
                    'home-page', 'author', 'author-email', 'license'):
            package[key] = pkg_info_dict.get(key)

        # It looks like FeedParser cannot deal with repeated headers
        classifiers = []
        for line in metadata.splitlines():
            if line.startswith('Classifier: '):
                classifiers.append(line[len('Classifier: '):])
        package['classifiers'] = classifiers

        if file_list:
            package['files'] = sorted(file_list)
        yield package