import base64
import logging
from typing import List, Optional
from fastapi import Depends, FastAPI, File, Form, HTTPException, UploadFile, status
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from pydantic import AnyHttpUrl, BaseModel, UrlConstraints
from contextlib import asynccontextmanager

from config import get_settings
import uvicorn
from utils.audio_utils import AudioUtils
from utils.caption_utils import ImageCaptioning
from utils.image_utils import UrlTest
from utils.topic_generation import TopicGenerator

# Setup logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Pydantic models for request/response
class TopicResponse(BaseModel):
    topics: List[str]
    caption: Optional[str]

class AudioResponse(BaseModel):
    audio_base64: str

class TranscriptionResponse(BaseModel):
    audio_transcription: str

# Context manager for startup and shutdown events
@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup
    app.state.topic_generator = TopicGenerator()
    app.state.img_caption = ImageCaptioning()
    app.state.audio_utils = AudioUtils()
    app.state.url_utils = UrlTest()
    logger.info("Application startup complete")
    yield
    # Shutdown
    logger.info("Application shutdown")

app = FastAPI(
    title="Rediones API",
    lifespan=lifespan,
)

# CORS
@app.on_event("startup")
async def startup_event():
    settings = get_settings()
    if settings.ALLOWED_ORIGINS:
        app.add_middleware(
            CORSMiddleware,
            allow_origins=settings.ALLOWED_ORIGINS,
            allow_credentials=True,
            allow_methods=["*"],
            allow_headers=["*"],
        )

@app.get("/")
async def root():
    return {"message": "Welcome To Rediones API"}

@app.get("/health")
async def health():
    return {"status": "OK"}

@app.post("/topicgen", response_model=TopicResponse)
async def generate_topic(
    img: UploadFile = File(None),
    text: Optional[str] = Form(None),
    img_url: Optional[AnyHttpUrl] = Form(None)
):
    try:
        if img_url and img:
            raise HTTPException(
                status_code=status.HTTP_400_BAD_REQUEST,
                detail="Only one of image_url or img can be accepted"
            )
        
        if text and not (img or img_url):
            generated_topics = app.state.topic_generator.generate_topics(text)
            return TopicResponse(topics=generated_topics, caption=None)

        if img or img_url:
            img_file_object = None
            if img:
                if not img.filename.lower().endswith((".jpg", ".png", ".jpeg")):
                    raise HTTPException(
                        status_code=status.HTTP_400_BAD_REQUEST,
                        detail="Image file must be ended with .jpg, .png, .jpeg"
                    )
                img_file_object = img.file
            elif img_url:
                img_file_object = app.state.url_utils.load_image(img_url)

            capt = app.state.img_caption.combo_model(img_file_object, text)
            return TopicResponse(topics=capt.topics, caption=capt.caption)

        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Enter text or image. Image URL and image file are mutually exclusive."
        )
    except Exception as e:
        logger.error(f"Error in generate_topic: {str(e)}")
        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="An unexpected error occurred")

@app.post("/audioverse", response_model=AudioResponse)
async def generate_audio(text: str):
    try:
        audio_bytes = app.state.audio_utils.speak(text)
        audio_base64 = base64.b64encode(audio_bytes).decode("utf-8")
        return AudioResponse(audio_base64=audio_base64)
    except Exception as e:
        logger.error(f"Error in generate_audio: {str(e)}")
        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="An unexpected error occurred")

@app.post("/transcribe", response_model=TranscriptionResponse)
async def transcribe_audio(
    audio: UploadFile = File(..., description="Audio file to be transcribed.")
):
    try:
        audio_transcribe = app.state.audio_utils.improved_transcribe(0.8, audio_file=audio.file)
        return TranscriptionResponse(audio_transcription=audio_transcribe)
    except Exception as e:
        logger.error(f"Error in transcribe_audio: {str(e)}")
        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="An unexpected error occurred")

if __name__ == "__main__":
    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)