refactor: restructure to core/ + ui/ with multi-threaded backend

ui/widgets/input_box.py

@@ -0,0 +1,50 @@
+"""输入框组件"""
+
+from textual.containers import Container
+from textual.widgets import Input
+from textual.message import Message
+
+
+class InputBox(Container):
+    """输入框组件"""
+
+    class SendMessage(Message):
+        """发送消息事件"""
+        def __init__(self, content: str) -> None:
+            self.content = content
+            super().__init__()
+
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+        self._history: list[str] = []
+        self._history_index: int = -1
+
+    def compose(self):
+        """构建输入框"""
+        yield Input(
+            placeholder="输入消息... (Enter发送)",
+            id="input-textarea"
+        )
+
+    def on_mount(self) -> None:
+        """组件挂载时"""
+        # 设置焦点
+        input_widget = self.query_one(Input)
+        input_widget.focus()
+
+    def on_input_submitted(self, event: Input.Submitted) -> None:
+        """处理输入提交事件"""
+        content = event.value.strip()
+        if content:
+            # 保存到历史
+            self._history.append(content)
+            self._history_index = len(self._history)
+            # 发送消息
+            self.post_message(self.SendMessage(content))
+            # 清空输入框
+            event.input.value = ""
+
+    def focus(self) -> None:
+        """聚焦输入框"""
+        input_widget = self.query_one(Input)
+        input_widget.focus()