from fastapi import FastAPI, Query
from pydantic import BaseModel
import cloudscraper
from bs4 import BeautifulSoup
from transformers import pipeline
import torch
import re
import os

os.environ["HF_HOME"] = "/home/user/huggingface"
os.environ["TRANSFORMERS_CACHE"] = "/home/user/huggingface"

app = FastAPI()

class ThreadResponse(BaseModel):
    question: str
    replies: list[str]

def clean_text(text: str) -> str:
    text = text.strip()
    text = re.sub(r"\b\d+\s*likes?,?\s*\d*\s*replies?$", "", text, flags=re.IGNORECASE).strip()
    return text

@app.get("/scrape", response_model=ThreadResponse)
def scrape(url: str = Query(...)):
    scraper = cloudscraper.create_scraper()
    response = scraper.get(url)

    if response.status_code == 200:
        soup = BeautifulSoup(response.content, 'html.parser')
        comment_containers = soup.find_all('div', class_='post__content')

        if comment_containers:
            question = clean_text(comment_containers[0].get_text(strip=True, separator="\n"))
            replies = [clean_text(comment.get_text(strip=True, separator="\n")) for comment in comment_containers[1:]]
            return ThreadResponse(question=question, replies=replies)
    return ThreadResponse(question="", replies=[])

MODEL_NAME = "google/flan-t5-small"

# Load the pipeline once at startup with device auto-mapping
text_generator = pipeline(
    "text2text-generation",
    model=MODEL_NAME,
    device=0 if torch.cuda.is_available() else -1,
    max_new_tokens=512,
    temperature=0.5
)

class PromptRequest(BaseModel):
    prompt: str

@app.post("/generate")
async def generate_text(request: PromptRequest):
    # Use the pipeline to generate text directly
    output = text_generator(request.prompt)[0]['generated_text']

    # Extract reasoning and content parts if thinking tags are present
    if "</think>" in output:
        reasoning_content = output.split("</think>")[0].strip()
        content = output.split("</think>")[1].strip().rstrip("</s>")
    else:
        reasoning_content = ""
        content = output.strip().rstrip("</s>")

    return {
        "reasoning_content": reasoning_content,
        "generated_text": content
    }