from fastapi import FastAPI, Request, Body, HTTPException, Depends
from fastapi.security import APIKeyHeader
from typing import Optional
from huggingface_hub import InferenceClient
import random

API_URL = "https://api-inference.huggingface.co/models/"
API_KEY = "abcd12345"  # Replace with your actual API key

client = InferenceClient("mistralai/Mistral-7B-Instruct-v0.1")
app = FastAPI()

security = APIKeyHeader(name="api_key", auto_error=False)

def get_api_key(api_key: Optional[str] = Depends(security)):
    if api_key is None or api_key != API_KEY:
        raise HTTPException(status_code=401, detail="Unauthorized access")
    return api_key

def format_prompt(message, history):
    prompt = "<s>"
    for user_prompt, bot_response in history:
        prompt += f"[INST] {user_prompt} [/INST]"
        prompt += f" {bot_response}</s> "
    prompt += f"[INST] {message} [/INST]"
    return prompt

@app.post("/api/v1/generate_text")
def generate_text(
    request: Request,
    body: dict = Body(...),
    api_key: str = Depends(get_api_key)
):
    prompt = body.get("prompt", "")
    sys_prompt = body.get("sysPrompt", "")
    temperature = body.get("temperature", 0.5)
    top_p = body.get("top_p", 0.95)
    repetition_penalty = body.get("repetition_penalty", 1.0)

    history = []  # You might need to handle this based on your actual usage
    formatted_prompt = format_prompt(prompt, history)

    stream = client.text_generation(
        formatted_prompt,
        temperature=temperature,
        max_new_tokens=512,
        top_p=top_p,
        repetition_penalty=repetition_penalty,
        do_sample=True,
        seed=random.randint(0, 10**7),
        stream=False,
        details=False,
        return_full_text=False
    )

    return stream