using Invercargill;

namespace Usm {

    public class CachedPackage {

        public string state_path { get; private set; }
        public string package_path { get; private set; }
        public string package_name { get; private set; }

        public CachedPackage(string path) {
            this.state_path = path;
            this.package_path = Path.build_filename(path, "package.usmc");
            this.package_name = Path.get_basename(path);
        }

        public Manifest get_manifest() throws Error {
            return new Manifest.from_package(package_path);
        }

        public OriginInformation get_origin_information() throws Error {
            return new OriginInformation.from_file(Path.build_filename(state_path, "origin-info"));
        }

        public bool has_build_directory() {
            return File.new_for_path(build_directory_path()).query_exists();
        }

        public bool has_build_archive() {
            return File.new_for_path(build_archive_path()).query_exists();
        }

        public string create_build_directory() throws Error {
            var path = build_directory_path();
            File.new_for_path(path).make_directory();
            return path;
        }

        public string get_build_directory() throws Error {
            var path = build_directory_path();
            if(File.new_for_path(path).query_exists()) {
                return path;
            }

            var archive_path = build_archive_path();
            if(!File.new_for_path(path).query_exists()) {
                throw new StateError.NO_BUILD_ARTIFACT(@"The package \"$package_name\" has no build artifact");
            }

            var proc = new Subprocess.newv(new string[] { "tar", "-xf", archive_path, "-C", path }, SubprocessFlags.INHERIT_FDS);
            if(!proc.wait_check()) {
                throw new StateError.EXTRACTION_FAILED(@"Could not extract \"$archive_path\": tar returned non-zero exit status $(proc.get_status())");
            }
            return path;
        }

        public string get_build_archive() throws Error {
            var path = build_archive_path();
            if(File.new_for_path(path).query_exists()) {
                return path;
            }

            var dir_path = build_directory_path();
            if(!File.new_for_path(dir_path).query_exists()) {
                throw new StateError.NO_BUILD_ARTIFACT(@"The package \"$package_name\" has no build artifact");
            }

            var proc = new Subprocess.newv(new string[] { "tar", "-cJf", path, "--directory", dir_path, "." }, SubprocessFlags.INHERIT_FDS);
            if(!proc.wait_check()) {
                throw new StateError.ARCHIVAL_FAILED(@"Could not archive \"$dir_path\": tar returned non-zero exit status $(proc.get_status())");
            }
            return path;
        }

        public void update_origin_information(OriginInformation info) throws Error {
            var properties = OriginInformation.get_mapper().map_from(info);
            var json = new InvercargillJson.JsonElement.from_properties(properties);
            json.write_to_file(Path.build_filename(state_path, "origin-info"));
        }

        private string build_directory_path() {
            return Path.build_filename(state_path, "build");
        }

        private string build_archive_path() {
            return Path.build_filename(state_path, "build.tar.xz");
        }

    }

}