feat: add mouse input handling to the terminal

lib/src/terminal.dart

@@ -1,6 +1,7 @@
 import 'dart:math' show max;
 
 import 'package:xterm/src/core/buffer/buffer.dart';
+import 'package:xterm/src/core/buffer/cell_offset.dart';
 import 'package:xterm/src/core/buffer/line.dart';
 import 'package:xterm/src/core/cursor.dart';
 import 'package:xterm/src/core/escape/emitter.dart';
@@ -9,6 +10,9 @@ import 'package:xterm/src/core/escape/parser.dart';
 import 'package:xterm/src/core/input/handler.dart';
 import 'package:xterm/src/core/input/keys.dart';
 import 'package:xterm/src/core/mouse/mode.dart';
+import 'package:xterm/src/core/mouse/button.dart';
+import 'package:xterm/src/core/mouse/button_state.dart';
+import 'package:xterm/src/core/mouse/handler.dart';
 import 'package:xterm/src/core/state.dart';
 import 'package:xterm/src/core/tabs.dart';
 import 'package:xterm/src/utils/ascii.dart';
@@ -44,8 +48,11 @@ class Terminal with Observable implements TerminalState, EscapeHandler {
     this.onResize,
     this.platform = TerminalTargetPlatform.unknown,
     this.inputHandler = defaultInputHandler,
+    this.mouseHandler = defaultMouseHandler,
   });
 
+  TerminalMouseHandler? mouseHandler;
+
   late final _parser = EscapeParser(this);
 
   final _emitter = const EscapeEmitter();
@@ -234,6 +241,23 @@ class Terminal with Observable implements TerminalState, EscapeHandler {
     }
   }
 
+  void mouseInput(
+    TerminalMouseButton button,
+    TerminalMouseButtonState buttonState,
+    CellOffset position,
+  ) {
+    final output = mouseHandler?.call(TerminalMouseEvent(
+      button: button,
+      buttonState: buttonState,
+      position: position,
+      state: this,
+      platform: platform,
+    ));
+    if (output != null) {
+      onOutput?.call(output);
+    }
+  }
+
   /// Resize the terminal screen. [newWidth] and [newHeight] should be greater
   /// than 0. Text reflow is currently not implemented and will be avaliable in
   /// the future.