Fix: 多个消息段转图片后显示异常 (#6)

* 🐛 修复多个消息段转图片后显示异常的问题

* 🍻 apply suggestions from code review

marisa/extension.py

@@ -1,6 +1,6 @@
 from nonebot_plugin_htmlrender import text_to_pic
-from nonebot_plugin_alconna.uniseg import UniMessage
 from nonebot.internal.adapter import Bot, Event, Message
+from nonebot_plugin_alconna.uniseg import Text, UniMessage
 from nonebot_plugin_alconna.extension import Extension, add_global_extension
 
 from .configs import TEMPLATE_DIR, config
@@ -17,12 +17,21 @@ def id(self) -> str:
 
     async def send_wrapper(
         self, bot: Bot, event: Event, send: str | Message | UniMessage
-    ):
-        if config.basic.send_with_image:
-            return UniMessage.image(
-                raw=await text_to_pic(
-                    str(send), css_path=str(TEMPLATE_DIR / "message.css")
+    ) -> str | Message | UniMessage:
+        plain_text = (
+            send.extract_plain_text()
+            if isinstance(send, Message | UniMessage)
+            else send
+        )
+        extra_segment = send.exclude(Text) if isinstance(send, UniMessage) else send
+        if config.basic.send_with_image and plain_text:
+            return (
+                UniMessage.image(
+                    raw=await text_to_pic(
+                        plain_text, css_path=str(TEMPLATE_DIR / "message.css")
+                    )
                 )
+                + extra_segment
             )
         return send