main.py

# main.py
from fastapi import FastAPI, Query
from fastapi.middleware.cors import CORSMiddleware
import requests
import os

from vector_index import VectorDB

vector_db = VectorDB.load("vector_db.pkl")


# ---------------------------
# FastAPI app
# ---------------------------
app = FastAPI(title="Smart AI Backend")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# ---------------------------
# OpenRouter settings
# ---------------------------
OPENROUTER_API_KEY = os.getenv("OPENROUTER_API_KEY")

API_URL = "https://openrouter.ai/api/v1/chat/completions"

HEADERS = {
    "Authorization": f"Bearer {OPENROUTER_API_KEY}",
    "Content-Type": "application/json",
    "HTTP-Referer": "https://huggingface.co",
    "X-Title": "My Free AI App"
}

MODEL = "meta-llama/llama-3.3-70b-instruct:free"  # FREE & fast





# ---------------------------
# AI Personality (System Prompt)
# ---------------------------

SYSTEM_PROMPT = """
You are a Men's Fashion Counsellor and Style Consultant.

Your job is to help men dress better while respecting:
- their personality
- comfort
- body type
- budget
- confidence level
- Indian climate and lifestyle

Tone:
- Warm
- Friendly
- Practical
- Confidence-boosting
- Non-judgmental

Style principles:
- Prefer timeless, clean fashion over short-lived trends
- Explain WHY an outfit works
- Suggest realistic, wearable combinations
- Avoid over-complication
- Help the user feel confident, not pressured

When needed:
- Ask simple clarifying questions
- Give step-by-step guidance
"""






# ---------------------------
# Routes
# ---------------------------

@app.get("/")
def home():
    return {"message": "Backend is working"}

@app.get("/chat")
def chat(prompt: str = Query(...)):
    if not OPENROUTER_API_KEY:
        return {"error": "OPENROUTER_API_KEY not set in Hugging Face Secrets"}

    payload = {
        "model": MODEL,
        "messages": [
            {"role": "system", "content": SYSTEM_PROMPT},
            {"role": "user", "content": prompt}
        ]
    }

    try:
        response = requests.post(
            API_URL,
            headers=HEADERS,
            json=payload,
            timeout=30
        )

        if response.status_code != 200:
            return {
                "error": "OpenRouter API error",
                "status_code": response.status_code,
                "details": response.text
            }

        data = response.json()
        reply = data["choices"][0]["message"]["content"]

        return {"reply": reply}

    except Exception as e:
        return {"error": str(e)}