from fastapi import FastAPI
from fastapi.responses import HTMLResponse
from pydantic import BaseModel
import joblib
import re

app = FastAPI(title="Hinglish Semantic Reaction Bot")

clf = None

class PredictRequest(BaseModel):
    text: str

class PredictResponse(BaseModel):
    emoji: str

def preprocess(text):
    text = text.lower()
    text = re.sub(r'[^a-z\s]', '', text)
    return text

@app.on_event("startup")
async def load_classifier():
    global clf
    print("Loading trained TF-IDF classifier...")
    clf = joblib.load("classifier.joblib")
    print("Startup complete. Classifier is ready.")

@app.get("/", response_class=HTMLResponse)
async def serve_ui():
    with open("index.html", "r") as f:
        html_content = f.read()
    return HTMLResponse(content=html_content)

@app.post("/api/predict", response_model=PredictResponse)
async def predict_emoji(request: PredictRequest):
    if not request.text.strip():
        return PredictResponse(emoji="🤔")

    cleaned_text = preprocess(request.text)
    predicted_emoji = clf.predict([cleaned_text])[0]
    return PredictResponse(emoji=predicted_emoji)