From be3481a7079076d144ac31679e0c2f6fcd7d2bdd Mon Sep 17 00:00:00 2001
From: Ekaropolus <git@hadox.org>
Date: Wed, 17 Sep 2025 14:48:20 -0600
Subject: [PATCH] API for lagchain r1

---
 polisplexity/urls.py       |  1 +
 pxy_langchain/api/urls.py  |  7 ++++
 pxy_langchain/api/views.py | 85 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 93 insertions(+)
 create mode 100644 pxy_langchain/api/urls.py
 create mode 100644 pxy_langchain/api/views.py

diff --git a/polisplexity/urls.py b/polisplexity/urls.py
index 65f47ec..f365ffd 100644
--- a/polisplexity/urls.py
+++ b/polisplexity/urls.py
@@ -46,6 +46,7 @@ urlpatterns = [
     path("share/", include("pxy_dashboard.share_urls")),  # ← NEW
 
     path("api/", include("pxy_bots.api.urls")),
+    path("api/langchain/", include("pxy_langchain.api.urls")),
 
 
 
diff --git a/pxy_langchain/api/urls.py b/pxy_langchain/api/urls.py
new file mode 100644
index 0000000..63a418a
--- /dev/null
+++ b/pxy_langchain/api/urls.py
@@ -0,0 +1,7 @@
+# pxy_langchain/api/urls.py
+from django.urls import path
+from .views import chat
+
+urlpatterns = [
+    path("chat", chat, name="langchain_chat_api"),
+]
diff --git a/pxy_langchain/api/views.py b/pxy_langchain/api/views.py
new file mode 100644
index 0000000..f6d8afb
--- /dev/null
+++ b/pxy_langchain/api/views.py
@@ -0,0 +1,85 @@
+# pxy_langchain/api/views.py
+import json
+import logging
+from typing import Optional
+
+from django.http import JsonResponse, HttpResponse
+from django.views.decorators.csrf import csrf_exempt
+
+from pxy_langchain.models import AIAssistant
+from pxy_langchain.services import LangchainAIService
+
+# We read the bot->assistant mapping from pxy_bots, so bots can decide which assistant to use.
+from pxy_bots.models import TelegramBot
+
+logger = logging.getLogger(__name__)
+
+
+def _get_assistant_for_req(req: dict) -> Optional[AIAssistant]:
+    """
+    Resolve which AIAssistant to use:
+      1) Try via TelegramBot (req['bot']['username'] matches TelegramBot.name or .username).
+      2) Fallback: optional req['context']['assistant_name'].
+    """
+    bot_username = (((req.get("bot") or {}).get("username")) or "").strip()
+    if bot_username:
+        # Try Bot.name first (that’s how your req.v1 is built), then .username
+        bot = (TelegramBot.objects.filter(name=bot_username).first() or
+               TelegramBot.objects.filter(username=bot_username).first())
+        if bot and bot.assistant_id:
+            return bot.assistant
+
+    # Fallback: explicit assistant name (optional)
+    ctx = req.get("context") or {}
+    assistant_name = (ctx.get("assistant_name") or "").strip()
+    if assistant_name:
+        return AIAssistant.objects.filter(name=assistant_name).first()
+
+    return None
+
+
+@csrf_exempt
+def chat(request):
+    """
+    POST /api/langchain/chat
+    Body: req.v1 (canonical envelope produced by pxy_bots)
+    Returns: render.v1 (text message with the LLM answer)
+    """
+    if request.method != "POST":
+        return HttpResponse(status=405)
+
+    try:
+        env = json.loads(request.body.decode("utf-8") or "{}")
+    except Exception:
+        return JsonResponse({"ok": False, "error": "invalid_json"}, status=400)
+
+    assistant = _get_assistant_for_req(env)
+    if not assistant:
+        return JsonResponse({"ok": False, "error": "assistant_not_found"}, status=400)
+
+    # Pull user text (or caption) from req.v1
+    inp = env.get("input") or {}
+    user_text = (inp.get("text") or inp.get("caption") or "").strip()
+
+    # If nothing to say, keep it explicit
+    if not user_text:
+        return JsonResponse({
+            "schema_version": "render.v1",
+            "messages": [{"type": "text", "text": "No text received."}]
+        })
+
+    try:
+        svc = LangchainAIService(assistant)
+        answer = svc.generate_response(user_text)  # synchronous call
+    except Exception as e:
+        logger.exception("langchain.chat.error")
+        return JsonResponse({"ok": False, "error": f"llm_error:{e.__class__.__name__}"}, status=500)
+
+    # Minimal render.v1
+    spec = {
+        "schema_version": "render.v1",
+        "messages": [
+            {"type": "text", "text": str(answer)}
+        ]
+    }
+    return JsonResponse(spec)