import os
os.environ["TRANSFORMERS_CACHE"] = "/tmp/hf-cache"
os.environ["HF_HOME"] = "/tmp/hf-home"

from fastapi import FastAPI, Request
from transformers import AutoModelForSequenceClassification, AutoTokenizer, AutoConfig
from scipy.special import softmax
import numpy as np

app = FastAPI()

MODEL = "cardiffnlp/twitter-roberta-base-sentiment-latest"

tokenizer = AutoTokenizer.from_pretrained(MODEL)
config = AutoConfig.from_pretrained(MODEL)
model = AutoModelForSequenceClassification.from_pretrained(MODEL)

def preprocess(text):
    tokens = []
    for t in text.split():
        if t.startswith("@") and len(t) > 1:
            t = "@user"
        elif t.startswith("http"):
            t = "http"
        tokens.append(t)
    return " ".join(tokens)

@app.post("/analyze")
async def analyze(request: Request):
    data = await request.json()
    text = preprocess(data.get("text", ""))
    encoded_input = tokenizer(text, return_tensors='pt')
    output = model(**encoded_input)
    scores = output[0][0].detach().numpy()
    scores = softmax(scores)
    result = [
        {"label": config.id2label[i], "score": round(float(scores[i]), 4)}
        for i in scores.argsort()[::-1]
    ]
    return {"result": result}