/// Coverage closeouts for `lib/src/terminal/src/core/escape/parser.dart`
/// (CUF/CUB/CPL with explicit param, insertLines with param, DEC mouse
/// mode 1001) and `lib/src/terminal/src/ui/render.dart` (the _onScroll
/// listener body, driven via a test ViewportOffset that exposes
/// notifyListeners).
library;

import 'package:clide/src/terminal/src/core/mouse/mode.dart';
import 'package:clide/src/terminal/src/terminal.dart';
import 'package:clide/src/terminal/src/terminal_view.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';

/// Minimal ViewportOffset that exposes `notifyListeners` so we can fire
/// it from a test. The real ScrollPositionWithSingleContext is hidden
/// inside Scrollable; this stand-in lets us drive the offset setter
/// path on RenderTerminal directly.
class _TestViewportOffset extends ViewportOffset {
  @override
  double get pixels => 0;
  @override
  bool get hasPixels => true;
  @override
  bool applyViewportDimension(double viewportDimension) => true;
  @override
  bool applyContentDimensions(double minScrollExtent, double maxScrollExtent) => true;
  @override
  void correctBy(double correction) {}
  @override
  void jumpTo(double pixels) {}
  @override
  Future<void> animateTo(double to, {required Duration duration, required Curve curve}) async {}
  @override
  ScrollDirection get userScrollDirection => ScrollDirection.idle;
  @override
  bool get allowImplicitScrolling => false;

  void fire() => notifyListeners();
}

Widget _host(Widget child) => Directionality(
  textDirection: TextDirection.ltr,
  child: MediaQuery(
    data: const MediaQueryData(),
    child: Center(child: SizedBox(width: 400, height: 200, child: child)),
  ),
);

void main() {
  group('EscapeParser — explicit-param CSI cursor moves', () {
    test('CUF (ESC [ Ps C) reads params[0] and normalises 0 → 1', () {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      t.write('A');
      // Cursor at (1,0). Move forward 3 cells, write 'B'.
      t.write('\x1b[3C');
      t.write('B');
      expect(t.buffer.cursorX, greaterThanOrEqualTo(4));
      // Param of 0 normalises to 1.
      t.write('\x1b[0C');
      t.write('C');
      expect(t.buffer.cursorX, greaterThanOrEqualTo(5));
    });

    test('CUB (ESC [ Ps D) reads params[0] and normalises 0 → 1', () {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      t.write('ABCDEFG');
      // Now at column 7. Step back 3.
      t.write('\x1b[3D');
      // Then 0-normalised step back 1.
      t.write('\x1b[0D');
      expect(t.buffer.cursorX, lessThan(7));
    });

    test('CPL (ESC [ Ps F) reads params[0] and normalises 0 → 1', () {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      t.write('line1\r\nline2\r\nline3');
      // Cursor on row 2. Go up 2 lines.
      t.write('\x1b[2F');
      // Then 0-normalised up 1.
      t.write('\x1b[0F');
      // Just verify the cursor moved upward — exact row is implementation
      // detail, but it shouldn't still be at row 2.
      expect(t.buffer.cursorY, lessThan(2));
    });

    test('insertLines (ESC [ Ps L) reads params[0]', () {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      t.write('row0\r\nrow1\r\nrow2');
      // Move cursor to home and insert 2 blank lines — just verifies the
      // path runs without throwing.
      t.write('\x1b[H\x1b[2L');
    });

    test('DEC private mode 1001 routes to MouseMode.upDownScroll', () {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      // Enable mode 1001.
      t.write('\x1b[?1001h');
      expect(t.mouseMode, MouseMode.upDownScroll);
      // Disable returns to none.
      t.write('\x1b[?1001l');
      expect(t.mouseMode, MouseMode.none);
    });
  });

  group('RenderTerminal — _onScroll listener', () {
    testWidgets('viewport-offset notifyListeners fires _onScroll without throwing', (tester) async {
      final t = Terminal(maxLines: 100, onOutput: (_) {});
      await tester.pumpWidget(_host(TerminalView(t)));
      await tester.pump();
      final r = tester.state<TerminalViewState>(find.byType(TerminalView)).renderTerminal;
      // Swap in a viewport offset we can fire on. The offset setter
      // attaches _onScroll as a listener.
      final off = _TestViewportOffset();
      r.offset = off;
      // Force a layout so attach() has wired up listeners.
      await tester.pump();
      // Drive the listener — runs the body of _onScroll (markNeedsLayout
      // + _notifyEditableRect).
      off.fire();
      await tester.pump();
    });
  });
}