// Pure-Dart tests for the run aggregate. No widgets, no bindings, no channel —
// this is the part that has to be correct regardless of what draws it.

import 'package:flutter_test/flutter_test.dart';
import 'package:iperf3gui/domain/models/iperf3_event.dart';
import 'package:iperf3gui/domain/models/iperf3_session.dart';

void main() {
  Iperf3Interval sample(double start, double bits,
          {int bytes = 1000, int? retransmits, bool omitted = false}) =>
      Iperf3Interval(
        start: start,
        end: start + 1,
        bytes: bytes,
        bitsPerSecond: bits,
        retransmits: retransmits,
        omitted: omitted,
      );

  group('Iperf3Session', () {
    test('starts empty', () {
      final session = Iperf3Session();
      expect(session.isEmpty, isTrue);
      expect(session.sampleCount, isZero);
      expect(session.intervals, isEmpty);
      expect(session.start, isNull);
      expect(session.summary, isNull);
      expect(session.errors, isEmpty);
      expect(session.stopped, isFalse);
      expect(session.hasError, isFalse);
    });

    test('statistics are null before any sample', () {
      final session = Iperf3Session();
      expect(session.latestBitsPerSecond, isNull);
      expect(session.meanBitsPerSecond, isNull);
      expect(session.peakBitsPerSecond, isNull);
      expect(session.totalRetransmits, isNull);
    });

    test('records start, intervals and summary', () {
      final session = Iperf3Session()
        ..add(const Iperf3Start(targetHost: 'host', targetPort: 5201))
        ..add(sample(0, 100))
        ..add(const Iperf3End(
          sent: Iperf3Total(seconds: 1, bytes: 10, bitsPerSecond: 80),
        ));
      expect(session.isEmpty, isFalse);
      expect(session.start!.targetHost, equals('host'));
      expect(session.sampleCount, equals(1));
      expect(session.summary!.sent!.bitsPerSecond, equals(80));
    });

    test('excludes omitted warm-up intervals from the series', () {
      final session = Iperf3Session()
        ..add(sample(0, 10, omitted: true))
        ..add(sample(1, 100))
        ..add(sample(2, 200));
      expect(session.sampleCount, equals(2));
      expect(session.meanBitsPerSecond, equals(150),
          reason: 'the omitted 10 would have pulled the mean to ~103');
    });

    test('computes mean, peak and latest over the samples', () {
      final session = Iperf3Session()
        ..add(sample(0, 100))
        ..add(sample(1, 400))
        ..add(sample(2, 250));
      expect(session.latestBitsPerSecond, equals(250));
      expect(session.peakBitsPerSecond, equals(400));
      expect(session.meanBitsPerSecond, equals(250));
    });

    test('sums sampled bytes', () {
      final session = Iperf3Session()
        ..add(sample(0, 1, bytes: 1500))
        ..add(sample(1, 1, bytes: 2500));
      expect(session.sampledBytes, equals(4000));
    });

    test('sums retransmits when reported', () {
      final session = Iperf3Session()
        ..add(sample(0, 1, retransmits: 2))
        ..add(sample(1, 1, retransmits: 5));
      expect(session.totalRetransmits, equals(7));
    });

    test('retransmits stay null when never reported, not zero', () {
      // UDP reports no retransmit counts; "not measured" must not read as 0.
      final session = Iperf3Session()
        ..add(sample(0, 1))
        ..add(sample(1, 1));
      expect(session.totalRetransmits, isNull);
    });

    test('collects errors in order and flags them', () {
      final session = Iperf3Session()
        ..add(const Iperf3Error('first'))
        ..add(const Iperf3Error('second'));
      expect(session.hasError, isTrue);
      expect(session.errors, equals(['first', 'second']));
      expect(session.isEmpty, isFalse);
    });

    test('records a stop', () {
      final session = Iperf3Session()..add(const Iperf3Stopped());
      expect(session.stopped, isTrue);
    });

    test('ignores log lines', () {
      final session = Iperf3Session()..add(const Iperf3LogLine('noise'));
      expect(session.isEmpty, isTrue);
    });

    test('clear returns it to the empty state', () {
      final session = Iperf3Session()
        ..add(const Iperf3Start(targetHost: 'host'))
        ..add(sample(0, 100))
        ..add(const Iperf3Error('boom'))
        ..add(const Iperf3Stopped())
        ..add(const Iperf3End())
        ..clear();
      expect(session.isEmpty, isTrue);
      expect(session.stopped, isFalse);
      expect(session.hasError, isFalse);
      expect(session.peakBitsPerSecond, isNull);
    });

    test('exposed collections are unmodifiable', () {
      final session = Iperf3Session()..add(sample(0, 1));
      expect(() => session.intervals.add(sample(1, 1)), throwsUnsupportedError);
      expect(() => session.errors.add('x'), throwsUnsupportedError);
    });
  });
}