Merge pull request #21 from damassi/feat/add-model-selection

feat: add model selection slash command

Author: damassi

CLAUDE.md

@@ -8,6 +8,7 @@
 - Run commands should be prefixed with `uv`: `uv run ...`
 - Use `asyncio` features, if such is needed
 - Prefer early returns
+- Private methods always go below public methods
 - Absolutely no useless comments! Every class and method does not need to be documented (unless it is legitimetly complex or "lib-ish")
 - Imports belong at the top of files, not inside functions (unless needed to avoid circular imports)
 

src/agent_chat_cli/components/chat_history.py

@@ -13,8 +13,8 @@
 
 class ChatHistory(Container):
     def add_message(self, message: Message) -> None:
-        widget = self._create_message(message)
-        self.mount(widget)
+        message_item = self._create_message(message)
+        self.mount(message_item)
 
     def _create_message(
         self, message: Message

src/agent_chat_cli/components/model_selection_menu.py

@@ -0,0 +1,51 @@
+from typing import TYPE_CHECKING
+
+from textual.widget import Widget
+from textual.app import ComposeResult
+from textual.containers import VerticalScroll
+from textual.widgets import OptionList
+from textual.widgets.option_list import Option
+
+if TYPE_CHECKING:
+    from agent_chat_cli.core.actions import Actions
+
+MODELS = [
+    {"id": "sonnet", "label": "Sonnet"},
+    {"id": "haiku", "label": "Haiku"},
+    {"id": "opus", "label": "Opus"},
+]
+
+
+class ModelSelectionMenu(Widget):
+    def __init__(self, actions: Actions) -> None:
+        super().__init__()
+        self.actions = actions
+
+    def compose(self) -> ComposeResult:
+        yield OptionList(*[Option(model["label"], id=model["id"]) for model in MODELS])
+
+    def show(self) -> None:
+        self.add_class("visible")
+
+        scroll_containers = self.app.query(VerticalScroll)
+        if scroll_containers:
+            scroll_containers.first().scroll_end(animate=False)
+
+        option_list = self.query_one(OptionList)
+        option_list.highlighted = 0
+        option_list.focus()
+
+    def hide(self) -> None:
+        self.remove_class("visible")
+
+    @property
+    def is_visible(self) -> bool:
+        return self.has_class("visible")
+
+    async def on_option_list_option_selected(
+        self, event: OptionList.OptionSelected
+    ) -> None:
+        self.hide()
+
+        if event.option_id:
+            await self.actions.change_model(event.option_id)

src/agent_chat_cli/components/slash_command_menu.py

@@ -11,6 +11,7 @@
 COMMANDS = [
     {"id": "new", "label": "/new   - Start new conversation"},
     {"id": "clear", "label": "/clear - Clear chat history"},
+    {"id": "model", "label": "/model - Change model"},
     {"id": "save", "label": "/save  - Save conversation to markdown"},
     {"id": "exit", "label": "/exit  - Exit"},
 ]
@@ -84,5 +85,7 @@ async def on_option_list_option_selected(
                 await self.actions.clear()
             case "new":
                 await self.actions.new()
+            case "model":
+                self.actions.show_model_menu()
             case "save":
                 await self.actions.save()

src/agent_chat_cli/components/user_input.py

@@ -7,6 +7,7 @@
 from agent_chat_cli.components.caret import Caret
 from agent_chat_cli.components.flex import Flex
 from agent_chat_cli.components.slash_command_menu import SlashCommandMenu
+from agent_chat_cli.components.model_selection_menu import ModelSelectionMenu
 from agent_chat_cli.core.actions import Actions
 from agent_chat_cli.utils.enums import Key
 
@@ -35,6 +36,7 @@ def compose(self) -> ComposeResult:
         yield SlashCommandMenu(
             actions=self.actions, on_filter_change=self._on_filter_change
         )
+        yield ModelSelectionMenu(actions=self.actions)
 
     def _on_filter_change(self, char: str) -> None:
         text_area = self.query_one(TextArea)
@@ -51,13 +53,15 @@ def on_descendant_blur(self, event: DescendantBlur) -> None:
         if not self.display:
             return
 
-        menu = self.query_one(SlashCommandMenu)
+        menu = self._get_visible_menu()
 
-        if isinstance(event.widget, TextArea) and not menu.is_visible:
+        if isinstance(event.widget, TextArea) and not menu:
             event.widget.focus(scroll_visible=False)
-        elif isinstance(event.widget, OptionList) and menu.is_visible:
-            menu.hide()
-            self.query_one(TextArea).focus(scroll_visible=False)
+        elif isinstance(event.widget, OptionList) and menu:
+            menu_option_list = menu.query_one(OptionList)
+            if event.widget == menu_option_list:
+                menu.hide()
+                self.query_one(TextArea).focus(scroll_visible=False)
 
     def on_text_area_changed(self, event: TextArea.Changed) -> None:
         menu = self.query_one(SlashCommandMenu)
@@ -68,10 +72,10 @@ def on_text_area_changed(self, event: TextArea.Changed) -> None:
             menu.show()
 
     async def on_key(self, event) -> None:
-        menu = self.query_one(SlashCommandMenu)
+        menu = self._get_visible_menu()
 
-        if menu.is_visible:
-            self._close_menu(event)
+        if menu:
+            self._close_menu(event, menu)
             return
 
         if event.key == "up":
@@ -92,9 +96,7 @@ def _insert_newline(self, event) -> None:
         input_widget = self.query_one(TextArea)
         input_widget.insert("\n")
 
-    def _close_menu(self, event) -> None:
-        menu = self.query_one(SlashCommandMenu)
-
+    def _close_menu(self, event, menu: SlashCommandMenu | ModelSelectionMenu) -> None:
         if event.key == Key.ESCAPE.value:
             event.stop()
             event.prevent_default()
@@ -104,7 +106,10 @@ def _close_menu(self, event) -> None:
             input_widget.focus()
             return
 
-        if event.key in (Key.BACKSPACE.value, Key.DELETE.value):
+        if isinstance(menu, SlashCommandMenu) and event.key in (
+            Key.BACKSPACE.value,
+            Key.DELETE.value,
+        ):
             if menu.filter_text:
                 menu.filter_text = menu.filter_text[:-1]
                 menu._refresh_options()
@@ -147,10 +152,21 @@ async def _navigate_history(self, event, direction: int) -> None:
         input_widget.text = self.message_history[self.history_index]
         input_widget.move_cursor_relative(rows=999, columns=999)
 
+    def _get_visible_menu(self) -> SlashCommandMenu | ModelSelectionMenu | None:
+        slash_menu = self.query_one(SlashCommandMenu)
+        if slash_menu.is_visible:
+            return slash_menu
+
+        model_menu = self.query_one(ModelSelectionMenu)
+        if model_menu.is_visible:
+            return model_menu
+
+        return None
+
     async def action_submit(self) -> None:
-        menu = self.query_one(SlashCommandMenu)
+        menu = self._get_visible_menu()
 
-        if menu.is_visible:
+        if menu:
             option_list = menu.query_one(OptionList)
             option_list.action_select()
             input_widget = self.query_one(TextArea)

src/agent_chat_cli/core/actions.py

@@ -4,6 +4,7 @@
 from agent_chat_cli.components.messages import RoleType
 from agent_chat_cli.components.chat_history import ChatHistory
 from agent_chat_cli.components.tool_permission_prompt import ToolPermissionPrompt
+from agent_chat_cli.components.model_selection_menu import ModelSelectionMenu
 from agent_chat_cli.utils.logger import log_json
 from agent_chat_cli.utils.save_conversation import save_conversation
 
@@ -72,5 +73,13 @@ async def save(self) -> None:
             f"Conversation saved to {file_path}", thinking=False
         )
 
+    def show_model_menu(self) -> None:
+        model_menu = self.app.query_one(ModelSelectionMenu)
+        model_menu.show()
+
+    async def change_model(self, model: str) -> None:
+        await self.app.agent_loop.change_model(model)
+        await self.post_system_message(f"Switched to {model}", thinking=False)
+
     async def _query(self, user_input: str) -> None:
         await self.app.agent_loop.query_queue.put(user_input)

src/agent_chat_cli/core/agent_loop.py

@@ -24,7 +24,12 @@
     get_available_servers,
     get_sdk_config,
 )
-from agent_chat_cli.utils.enums import AppEventType, ContentType, ControlCommand
+from agent_chat_cli.utils.enums import (
+    AppEventType,
+    ContentType,
+    ControlCommand,
+    ModelChangeCommand,
+)
 from agent_chat_cli.utils.logger import log_json
 from agent_chat_cli.utils.mcp_server_status import MCPServerStatus
 
@@ -51,36 +56,33 @@ def __init__(
 
         self.client: ClaudeSDKClient
 
-        self.query_queue: asyncio.Queue[str | ControlCommand] = asyncio.Queue()
+        self.query_queue: asyncio.Queue[str | ControlCommand | ModelChangeCommand] = (
+            asyncio.Queue()
+        )
         self.permission_response_queue: asyncio.Queue[str] = asyncio.Queue()
         self.permission_lock = asyncio.Lock()
 
         self._running = False
 
     async def start(self) -> None:
-        mcp_servers = {
-            name: config.model_dump() for name, config in self.available_servers.items()
-        }
-
-        await self._initialize_client(mcp_servers=mcp_servers)
+        await self._initialize_client()
 
         self._running = True
 
         while self._running:
             user_input = await self.query_queue.get()
 
+            if isinstance(user_input, ModelChangeCommand):
+                self.config.model = user_input.model
+                await self.client.disconnect()
+                await self._initialize_client()
+                continue
+
             if isinstance(user_input, ControlCommand):
                 if user_input == ControlCommand.NEW_CONVERSATION:
                     await self.client.disconnect()
-
                     self.session_id = None
-
-                    mcp_servers = {
-                        name: config.model_dump()
-                        for name, config in self.available_servers.items()
-                    }
-
-                    await self._initialize_client(mcp_servers=mcp_servers)
+                    await self._initialize_client()
                 continue
 
             self.app.ui_state.set_interrupting(False)
@@ -97,7 +99,17 @@ async def start(self) -> None:
                 AppEvent(type=AppEventType.RESULT, data=None)
             )
 
-    async def _initialize_client(self, mcp_servers: dict) -> None:
+    async def change_model(self, model: str) -> None:
+        await self.query_queue.put(
+            ModelChangeCommand(ControlCommand.CHANGE_MODEL, model)
+        )
+
+    async def _initialize_client(self, mcp_servers: dict | None = None) -> None:
+        if mcp_servers is None:
+            mcp_servers = {
+                name: config.model_dump()
+                for name, config in self.available_servers.items()
+            }
         sdk_config = get_sdk_config(self.config)
 
         sdk_config["mcp_servers"] = mcp_servers

src/agent_chat_cli/core/styles.tcss

@@ -108,17 +108,17 @@ TextArea .text-area--cursor {
     padding-left: 2;
 }
 
-SlashCommandMenu {
+SlashCommandMenu, ModelSelectionMenu {
     height: auto;
     max-height: 10;
     display: none;
 }
 
-SlashCommandMenu.visible {
+SlashCommandMenu.visible, ModelSelectionMenu.visible {
     display: block;
 }
 
-SlashCommandMenu OptionList {
+SlashCommandMenu OptionList, ModelSelectionMenu OptionList {
     height: auto;
     max-height: 10;
     border: solid $primary;

src/agent_chat_cli/utils/enums.py

@@ -1,4 +1,5 @@
 from enum import Enum
+from typing import NamedTuple
 
 
 class AppEventType(Enum):
@@ -20,10 +21,16 @@ class ContentType(Enum):
 
 class ControlCommand(Enum):
     NEW_CONVERSATION = "new_conversation"
+    CHANGE_MODEL = "change_model"
     EXIT = "exit"
     CLEAR = "clear"
 
 
+class ModelChangeCommand(NamedTuple):
+    command: ControlCommand
+    model: str
+
+
 class Key(Enum):
     ENTER = "enter"
     ESCAPE = "escape"