import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'package:http_server/http_server.dart';
import 'package:mime/mime.dart';
import 'body_parse_result.dart';
import 'chunk.dart';
import 'file_upload_info.dart';
import 'map_from_uri.dart';

/// Grabs data from an incoming request.
///
/// Supports URL-encoded and JSON, as well as multipart/* forms.
/// On a file upload request, only fields with the name **'file'** are processed
/// as files. Anything else is put in the body. You can change the upload file name
/// via the *fileUploadName* parameter. :)
Future<BodyParseResult> parseBody(HttpRequest request) async {
  var result = new BodyParseResult();

  if (request.headers.contentType != null) {
    if (request.headers.contentType.primaryType == 'multipart' &&
        request.headers.contentType.parameters.containsKey('boundary')) {
      var parts = request
          .transform(new MimeMultipartTransformer(
              request.headers.contentType.parameters['boundary']))
          .map((part) =>
              HttpMultipartFormData.parse(part, defaultEncoding: UTF8));

      await for (HttpMultipartFormData part in parts) {
        if (part.isBinary || part.contentDisposition.parameters.containsKey("filename")) {
          BytesBuilder builder = await part.fold(new BytesBuilder(), (BytesBuilder b,  d) => b..add(d is! String ? d : d.codeUnits));
          var upload = new FileUploadInfo(
              mimeType: part.contentType.mimeType,
              name: part.contentDisposition.parameters['name'],
              filename: part.contentDisposition.parameters['filename'] ?? 'file',
              data: builder.takeBytes());
          result.files.add(upload);
        } else if (part.isText) {
          var text = await part.join();
          buildMapFromUri(result.body, '${part.contentDisposition.parameters["name"]}=$text');
        }  else {
          print("Found something else : ${part.contentDisposition}");
        }
      }
    } else if (request.headers.contentType.mimeType ==
        ContentType.JSON.mimeType) {
      result.body
          .addAll(JSON.decode(await request.transform(UTF8.decoder).join()));
    } else if (request.headers.contentType.mimeType ==
        'application/x-www-form-urlencoded') {
      String body = await request.transform(UTF8.decoder).join();
      buildMapFromUri(result.body, body);
    }
  } else if (request.uri.hasQuery) {
    buildMapFromUri(result.query, request.uri.query);
  }

  return result;
}