// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:async';
import 'dart:convert';

import 'package:test/test.dart';

import 'package:http/src/message.dart';

/// A non-ASCII string.
final _nonAscii = "föøbãr";

/// The UTF-8 encoding of [_nonAscii].
final _utf8Bytes = utf8.encode(_nonAscii);

/// The Latin-1 encoding of [_nonAscii].
final _latin1Bytes = latin1.encode(_nonAscii);

/// The ASCII bytes in the string "hello,".
final _helloBytes = ascii.encode("hello,");

/// The ASCII bytes in the string " world".
final _worldBytes = ascii.encode(" world");

class _TestMessage extends Message {
  _TestMessage(Map<String, String> headers, Map<String, Object> context, body,
      Encoding encoding)
      : super(body, headers: headers, context: context, encoding: encoding);

  Message change(
      {Map<String, String> headers, Map<String, Object> context, body}) {
    throw new UnimplementedError();
  }
}

Message _createMessage(
        {Map<String, String> headers,
        Map<String, Object> context,
        body,
        Encoding encoding}) =>
    new _TestMessage(headers, context, body, encoding);

void main() {
  group('headers', () {
    test('are case insensitive', () {
      var message = _createMessage(headers: {'foo': 'bar'});

      expect(message.headers, containsPair('foo', 'bar'));
      expect(message.headers, containsPair('Foo', 'bar'));
      expect(message.headers, containsPair('FOO', 'bar'));
    });

    test('default to a constant map', () {
      var message = _createMessage();
      expect(message.headers, hasLength(1));
      expect(message.headers.containsKey('content-length'), isTrue);
      expect(message.headers, same(_createMessage().headers));
      expect(() => message.headers['h1'] = 'value1', throwsUnsupportedError);
    });

    test('are immutable', () {
      var message = _createMessage(headers: {'h1': 'value'});
      expect(() => message.headers['h1'] = 'value', throwsUnsupportedError);
    });
  });

  group('context', () {
    test('is accessible', () {
      var message = _createMessage(context: {'foo': 'bar'});
      expect(message.context, containsPair('foo', 'bar'));
    });

    test('defaults to an empty immutable map', () {
      var message = _createMessage();
      expect(message.context, isEmpty);
      expect(() => message.context['key'] = 'value', throwsUnsupportedError);
    });

    test('is immutable', () {
      var message = _createMessage(context: {'key': 'value'});
      expect(() => message.context['key'] = 'value', throwsUnsupportedError);
    });
  });

  group("readAsString()", () {
    test("returns an empty string for an empty body", () {
      var message = _createMessage();
      expect(message.readAsString(), completion(isEmpty));
    });

    test("collects a streamed body", () async {
      var controller = new StreamController();
      var message = _createMessage(body: controller.stream);
      expect(message.readAsString(), completion(equals("hello, world")));

      controller.add(_helloBytes);
      await pumpEventQueue();
      controller.add(_worldBytes);
      controller.close();
    });

    test("defaults to decoding the message as UTF-8", () {
      var message = _createMessage(body: _utf8Bytes);
      expect(message.readAsString(), completion(equals(_nonAscii)));
    });
  });

  group("readAsBytes()", () {
    test("returns an empty list for an empty body", () {
      var message = _createMessage();
      expect(message.readAsBytes(), completion(isEmpty));
    });

    test("collects a streamed body", () async {
      var controller = new StreamController();
      var message = _createMessage(body: controller.stream);
      expect(message.readAsBytes(),
          completion(equals([]..addAll(_helloBytes)..addAll(_worldBytes))));

      controller.add(_helloBytes);
      await pumpEventQueue();
      controller.add(_worldBytes);
      controller.close();
    });
  });

  group("read()", () {
    test("returns an empty stream for an empty body", () {
      var message = _createMessage();
      expect(message.read().toList(), completion(isEmpty));
    });

    test("returns a streamed body", () async {
      var controller = new StreamController();
      var message = _createMessage(body: controller.stream);
      expect(message.read().toList(),
          completion(equals([_helloBytes, _worldBytes])));

      controller.add(_helloBytes);
      await pumpEventQueue();
      controller.add(_worldBytes);
      controller.close();
    });

    test("returns a List<int> body", () {
      var message = _createMessage(body: _helloBytes);
      expect(message.read().toList(), completion(equals([_helloBytes])));
    });

    test("throws when calling read()/readAsString() multiple times", () {
      var message = _createMessage();
      expect(message.read().toList(), completion(isEmpty));
      expect(() => message.read(), throwsStateError);

      message = _createMessage();
      expect(message.readAsString(), completion(isEmpty));
      expect(() => message.readAsString(), throwsStateError);

      message = _createMessage();
      expect(message.readAsString(), completion(isEmpty));
      expect(() => message.read(), throwsStateError);

      message = _createMessage();
      expect(message.read().toList(), completion(isEmpty));
      expect(() => message.readAsString(), throwsStateError);
    });
  });

  group("content-length", () {
    test("is 0 with a default body and without a content-length header", () {
      var request = _createMessage();
      expect(request.contentLength, 0);
    });

    test("comes from a byte body", () {
      var message = _createMessage(body: [1, 2, 3]);
      expect(message.contentLength, 3);
      expect(message.isEmpty, isFalse);
    });

    test("comes from a string body", () {
      var message = _createMessage(body: 'foobar');
      expect(message.contentLength, 6);
      expect(message.isEmpty, isFalse);
    });

    test("is set based on byte length for a string body", () {
      var message = _createMessage(body: 'fööbär');
      expect(message.contentLength, 9);
      expect(message.isEmpty, isFalse);

      message = _createMessage(body: 'fööbär', encoding: latin1);
      expect(message.contentLength, 6);
      expect(message.isEmpty, isFalse);
    });

    test("is null for a stream body", () {
      var message = _createMessage(body: const Stream.empty());
      expect(message.contentLength, isNull);
    });

    test("uses the content-length header for a stream body", () {
      var message = _createMessage(
          body: const Stream.empty(), headers: {'content-length': '42'});
      expect(message.contentLength, 42);
      expect(message.isEmpty, isFalse);
    });

    test("real body length takes precedence over content-length header", () {
      var message =
          _createMessage(body: [1, 2, 3], headers: {'content-length': '42'});
      expect(message.contentLength, 3);
      expect(message.isEmpty, isFalse);
    });

    test("is null for a chunked transfer encoding", () {
      var message = _createMessage(
          body: "1\r\na0\r\n\r\n", headers: {'transfer-encoding': 'chunked'});
      expect(message.contentLength, isNull);
    });

    test("is null for a non-identity transfer encoding", () {
      var message = _createMessage(
          body: "1\r\na0\r\n\r\n", headers: {'transfer-encoding': 'custom'});
      expect(message.contentLength, isNull);
    });

    test("is set for identity transfer encoding", () {
      var message = _createMessage(
          body: "1\r\na0\r\n\r\n", headers: {'transfer-encoding': 'identity'});
      expect(message.contentLength, equals(9));
      expect(message.isEmpty, isFalse);
    });
  });

  group("mimeType", () {
    test("is null without a content-type header", () {
      expect(_createMessage().mimeType, isNull);
    });

    test("comes from the content-type header", () {
      expect(_createMessage(headers: {'content-type': 'text/plain'}).mimeType,
          equals('text/plain'));
    });

    test("doesn't include parameters", () {
      expect(
          _createMessage(
                  headers: {'content-type': 'text/plain; foo=bar; bar=baz'})
              .mimeType,
          equals('text/plain'));
    });
  });

  group('encoding', () {
    group('is null and content-type header is unchanged with', () {
      group('no content-type header and', () {
        test('no body', () {
          var message = _createMessage();
          expect(message.encoding, isNull);
          expect(message.headers, isNot(contains('content-type')));
        });

        test('a plain ASCII body', () {
          var message = _createMessage(body: "foo");
          expect(message.encoding, isNull);
          expect(message.headers, isNot(contains('content-type')));
        });

        test('body bytes', () {
          var message = _createMessage(body: _utf8Bytes);
          expect(message.encoding, isNull);
          expect(message.headers, isNot(contains('content-type')));
        });
      });

      group('an unknown content-type header and', () {
        test('no body', () {
          var message = _createMessage(headers: {
            'Content-Type': 'text/plain; charset=not-a-real-charset'
          });
          expect(message.encoding, isNull);
          expect(
              message.headers,
              containsPair(
                  'content-type', 'text/plain; charset=not-a-real-charset'));
        });

        test('a plain ASCII body', () {
          var message = _createMessage(body: "foo", headers: {
            'Content-Type': 'text/plain; charset=not-a-real-charset'
          });
          expect(message.encoding, isNull);
          expect(
              message.headers,
              containsPair(
                  'content-type', 'text/plain; charset=not-a-real-charset'));
        });

        test('body bytes', () {
          var message = _createMessage(body: _utf8Bytes, headers: {
            'Content-Type': 'text/plain; charset=not-a-real-charset'
          });
          expect(message.encoding, isNull);
          expect(
              message.headers,
              containsPair(
                  'content-type', 'text/plain; charset=not-a-real-charset'));
          expect(message.readAsString(), completion(equals(_nonAscii)));
        });
      });
    });

    group('defaults to UTF-8 with a non-ASCII body and', () {
      test('no content-type header', () {
        var message = _createMessage(body: _nonAscii);
        expect(message.encoding, equals(utf8));
        expect(
            message.headers,
            containsPair(
                'content-type', 'application/octet-stream; charset=utf-8'));
        expect(message.readAsBytes(), completion(equals(_utf8Bytes)));
      });

      test('a content-type header', () {
        var message = _createMessage(
            body: _nonAscii,
            headers: {'Content-Type': 'text/plain; charset=iso-8859-1'});
        expect(message.encoding, equals(utf8));
        expect(message.headers,
            containsPair('content-type', 'text/plain; charset=utf-8'));
        expect(message.readAsBytes(), completion(equals(_utf8Bytes)));
      });
    });

    group('uses the encoding parameter with', () {
      group('no content-type header and', () {
        test('no body', () {
          var message = _createMessage(encoding: latin1);
          expect(message.encoding, equals(latin1));
          expect(
              message.headers,
              containsPair('content-type',
                  'application/octet-stream; charset=iso-8859-1'));
        });

        test('a plain ASCII body', () {
          var message = _createMessage(body: "foo", encoding: latin1);
          expect(message.encoding, equals(latin1));
          expect(
              message.headers,
              containsPair('content-type',
                  'application/octet-stream; charset=iso-8859-1'));
        });

        test('a non-ASCII body', () {
          var message = _createMessage(body: _nonAscii, encoding: latin1);
          expect(message.encoding, equals(latin1));
          expect(
              message.headers,
              containsPair('content-type',
                  'application/octet-stream; charset=iso-8859-1'));
          expect(message.readAsBytes(), completion(equals(_latin1Bytes)));
        });

        test('body bytes', () {
          var message = _createMessage(encoding: latin1, body: _latin1Bytes);
          expect(message.encoding, equals(latin1));
          expect(
              message.headers,
              containsPair('content-type',
                  'application/octet-stream; charset=iso-8859-1'));
          expect(message.readAsString(), completion(equals(_nonAscii)));
        });
      });

      test('a content-type header without a charset', () {
        var message = _createMessage(
            encoding: latin1, headers: {'Content-Type': 'text/plain'});
        expect(message.headers,
            containsPair('content-type', 'text/plain; charset=iso-8859-1'));
      });

      group('a content-type header and', () {
        test('no body', () {
          var message = _createMessage(
              encoding: latin1,
              headers: {'Content-Type': 'text/plain; charset=utf-8'});
          expect(message.encoding, equals(latin1));
          expect(message.headers,
              containsPair('content-type', 'text/plain; charset=iso-8859-1'));
        });

        test('a plain ASCII body', () {
          var message = _createMessage(
              body: "foo",
              encoding: latin1,
              headers: {'Content-Type': 'text/plain; charset=utf-8'});
          expect(message.encoding, equals(latin1));
          expect(message.headers,
              containsPair('content-type', 'text/plain; charset=iso-8859-1'));
        });

        test('a non-ASCII body', () {
          var message = _createMessage(
              body: _nonAscii,
              encoding: latin1,
              headers: {'Content-Type': 'text/plain; charset=utf-8'});
          expect(message.encoding, equals(latin1));
          expect(message.headers,
              containsPair('content-type', 'text/plain; charset=iso-8859-1'));
          expect(message.readAsBytes(), completion(equals(_latin1Bytes)));
        });

        test('body bytes', () {
          var message = _createMessage(
              encoding: latin1,
              body: _latin1Bytes,
              headers: {'Content-Type': 'text/plain; charset=utf-8'});
          expect(message.encoding, equals(latin1));
          expect(message.headers,
              containsPair('content-type', 'text/plain; charset=iso-8859-1'));
          expect(message.readAsString(), completion(equals(_nonAscii)));
        });
      });
    });

    group('uses the content-type header with', () {
      test('no body', () {
        var message = _createMessage(
            headers: {'Content-Type': 'text/plain; charset=iso-8859-1'});
        expect(message.encoding.name, equals(latin1.name));
        expect(message.headers,
            containsPair('content-type', 'text/plain; charset=iso-8859-1'));
      });

      test('a plain ASCII body', () {
        var message = _createMessage(
            body: "foo",
            headers: {'Content-Type': 'text/plain; charset=iso-8859-1'});
        expect(message.encoding.name, equals(latin1.name));
        expect(message.headers,
            containsPair('content-type', 'text/plain; charset=iso-8859-1'));
      });

      test('body bytes', () {
        var message = _createMessage(
            body: _latin1Bytes,
            headers: {'Content-Type': 'text/plain; charset=iso-8859-1'});
        expect(message.encoding.name, equals(latin1.name));
        expect(message.headers,
            containsPair('content-type', 'text/plain; charset=iso-8859-1'));
        expect(message.readAsString(), completion(equals(_nonAscii)));
      });
    });
  });
}