import "dart:convert";
import "dart:io";
import "package:cli_tools/config.dart";
import "package:http/http.dart" as http;
import "package:lasuite_docs_proxy/models/settings.dart";
import "package:shelf/shelf.dart";
import "package:shelf/shelf_io.dart";
import "package:shelf_router/shelf_router.dart";

void main(List<String> argsRaw) async {
  final parser = ConfigParser()
    ..addOption("socket", abbr: "s", mandatory: true)
    ..addOption("authUri", abbr: "a", mandatory: true)
    ..addOption("minioUri", abbr: "m", mandatory: true);

  final args = parser.parse(argsRaw);
  final settings = Settings.fromJson(<String, dynamic>{
    for (final opt in args.options) opt: args.option(opt),
  });

  final handler = const Pipeline()
      .addMiddleware(logRequests())
      .addHandler(
        (Router()..get("/media/<path|.*>", (
              Request request,
              String path,
            ) async {
              final authResponse = await http.get(
                settings.authUri,
                headers: {
                  ...request.headers,
                  'x-original-url': request.requestedUri.toString(),
                },
              );

              if (authResponse.statusCode != 200) {
                return Response(
                  authResponse.statusCode,
                  body: json.encode({
                    "error":
                        "An error occurred when calling `authUri`: ${authResponse.body}.",
                  }),
                  headers: {HttpHeaders.contentTypeHeader: "application/json"},
                );
              }

              final authHeaders = {
                for (final header in [
                  'authorization',
                  'x-amz-date',
                  'x-amz-content-sha256',
                ])
                  if (authResponse.headers[header] case final value?)
                    header: value,
              };

              final minioUrl = settings.minioUri.replace(
                path: "/lasuite-docs/$path",
                query: request.url.query,
              );

              final minioResponse = await http.get(
                minioUrl,
                headers: {...authHeaders},
              );

              return Response(
                minioResponse.statusCode,
                body: minioResponse.bodyBytes,
                headers: {
                  ...minioResponse.headers,
                  'content-security-policy': "default-src 'none'",
                },
              );
            }))
            .call,
      );

  final server = HttpServer.listenOn(
    await ServerSocket.bind(
      InternetAddress(settings.socket, type: InternetAddressType.unix),
      0,
    ),
  );

  serveRequests(server, handler);
  print("Proxy listening at ${server.address.address}");
}