deploy: credits.py

credits.py

@@ -0,0 +1,37 @@
+from fastapi import HTTPException
+from db import supabase
+from datetime import datetime, timezone
+
+PLAN_CREDITS = {"free": 100, "hobby": 5_000, "team": 25_000,
+                "business": 100_000, "enterprise": 999_999_999}
+
+async def check_and_deduct_credits(user_id: str, cost: int) -> int:
+    res  = (supabase.table("users")
+            .select("credits_remaining,plan,credits_reset_at")
+            .eq("id", user_id).single().execute())
+    user = res.data
+    if not user: raise HTTPException(404, "User not found")
+
+    if user["plan"] == "free":
+        reset = datetime.fromisoformat(user["credits_reset_at"])
+        now   = datetime.now(timezone.utc)
+        if now > reset:
+            supabase.table("users").update({
+                "credits_remaining": PLAN_CREDITS["free"],
+                "credits_reset_at": now.replace(hour=0,minute=0,second=0).isoformat()
+            }).eq("id", user_id).execute()
+            user["credits_remaining"] = PLAN_CREDITS["free"]
+
+    if user["credits_remaining"] < cost:
+        raise HTTPException(429, {
+            "error": "Out of credits", "plan": user["plan"],
+            "credits_remaining": user["credits_remaining"],
+            "upgrade_url": "https://nurricai.com/pricing"})
+
+    new_bal = user["credits_remaining"] - cost
+    supabase.table("users").update({"credits_remaining": new_bal}).eq("id", user_id).execute()
+    supabase.table("usage_logs").insert({
+        "user_id": user_id, "credits_used": cost,
+        "timestamp": datetime.now(timezone.utc).isoformat()
+    }).execute()
+    return new_bal