// Copyright (c) 2014, 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:shelf/src/message.dart';
import 'package:test/test.dart';

import 'test_util.dart';

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 UnimplementedError();
  }
}

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

void main() {
  group('headers', () {
    test('message headers 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('null header value becomes default', () {
      var message = _createMessage();
      expect(message.headers, equals({'content-length': '0'}));
      expect(message.headers, containsPair('CoNtEnT-lEnGtH', '0'));
      expect(message.headers, same(_createMessage().headers));
      expect(() => message.headers['h1'] = 'value1', throwsUnsupportedError);
    });

    test('headers are immutable', () {
      var message = _createMessage(headers: {'h1': 'value1'});
      expect(() => message.headers['h1'] = 'value1', throwsUnsupportedError);
      expect(() => message.headers['h1'] = 'value2', throwsUnsupportedError);
      expect(() => message.headers['h2'] = 'value2', throwsUnsupportedError);
    });
  });

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

    test('null context value becomes empty and immutable', () {
      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);
      expect(() => message.context['key2'] = 'value', throwsUnsupportedError);
    });
  });

  group("readAsString", () {
    test("supports a null body", () {
      var request = _createMessage();
      expect(request.readAsString(), completion(equals("")));
    });

    test("supports a Stream<List<int>> body", () {
      var controller = StreamController();
      var request = _createMessage(body: controller.stream);
      expect(request.readAsString(), completion(equals("hello, world")));

      controller.add(helloBytes);
      return Future(() {
        controller
          ..add(worldBytes)
          ..close();
      });
    });

    test("defaults to UTF-8", () {
      var request = _createMessage(
          body: Stream.fromIterable([
        [195, 168]
      ]));
      expect(request.readAsString(), completion(equals("è")));
    });

    test("the content-type header overrides the default", () {
      var request = _createMessage(
          headers: {'content-type': 'text/plain; charset=iso-8859-1'},
          body: Stream.fromIterable([
            [195, 168]
          ]));
      expect(request.readAsString(), completion(equals("Ã¨")));
    });

    test("an explicit encoding overrides the content-type header", () {
      var request = _createMessage(
          headers: {'content-type': 'text/plain; charset=iso-8859-1'},
          body: Stream.fromIterable([
            [195, 168]
          ]));
      expect(request.readAsString(latin1), completion(equals("Ã¨")));
    });
  });

  group("read", () {
    test("supports a null body", () {
      var request = _createMessage();
      expect(request.read().toList(), completion(isEmpty));
    });

    test("supports a Stream<List<int>> body", () {
      var controller = StreamController();
      var request = _createMessage(body: controller.stream);
      expect(request.read().toList(),
          completion(equals([helloBytes, worldBytes])));

      controller.add(helloBytes);
      return Future(() {
        controller
          ..add(worldBytes)
          ..close();
      });
    });

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

    test("throws when calling read()/readAsString() multiple times", () {
      var request;

      request = _createMessage();
      expect(request.read().toList(), completion(isEmpty));
      expect(() => request.read(), throwsStateError);

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

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

      request = _createMessage();
      expect(request.read().toList(), completion(isEmpty));
      expect(() => request.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 request = _createMessage(body: [1, 2, 3]);
      expect(request.contentLength, 3);
    });

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

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

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

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

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

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

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

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

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

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

    test("is null without a charset parameter", () {
      expect(_createMessage(headers: {'content-type': 'text/plain'}).encoding,
          isNull);
    });

    test("is null with an unrecognized charset parameter", () {
      expect(
          _createMessage(
              headers: {'content-type': 'text/plain; charset=fblthp'}).encoding,
          isNull);
    });

    test("comes from the content-type charset parameter", () {
      expect(
          _createMessage(
                  headers: {'content-type': 'text/plain; charset=iso-8859-1'})
              .encoding,
          equals(latin1));
    });

    test("comes from the content-type charset parameter with a different case",
        () {
      expect(
          _createMessage(
                  headers: {'Content-Type': 'text/plain; charset=iso-8859-1'})
              .encoding,
          equals(latin1));
    });

    test("defaults to encoding a String as UTF-8", () {
      expect(
          _createMessage(body: "è").read().toList(),
          completion(equals([
            [195, 168]
          ])));
    });

    test("uses the explicit encoding if available", () {
      expect(
          _createMessage(body: "è", encoding: latin1).read().toList(),
          completion(equals([
            [232]
          ])));
    });

    test("adds an explicit encoding to the content-type", () {
      var request = _createMessage(
          body: "è", encoding: latin1, headers: {'content-type': 'text/plain'});
      expect(request.headers,
          containsPair('content-type', 'text/plain; charset=iso-8859-1'));
    });

    test("adds an explicit encoding to the content-type with a different case",
        () {
      var request = _createMessage(
          body: "è", encoding: latin1, headers: {'Content-Type': 'text/plain'});
      expect(request.headers,
          containsPair('Content-Type', 'text/plain; charset=iso-8859-1'));
    });

    test(
        "sets an absent content-type to application/octet-stream in order to "
        "set the charset", () {
      var request = _createMessage(body: "è", encoding: latin1);
      expect(
          request.headers,
          containsPair(
              'content-type', 'application/octet-stream; charset=iso-8859-1'));
    });

    test("overwrites an existing charset if given an explicit encoding", () {
      var request = _createMessage(
          body: "è",
          encoding: latin1,
          headers: {'content-type': 'text/plain; charset=whatever'});
      expect(request.headers,
          containsPair('content-type', 'text/plain; charset=iso-8859-1'));
    });
  });
}