import logging
import os
from fastapi import FastAPI, HTTPException
from fastapi.responses import FileResponse,RedirectResponse
import boto3
from pydantic import BaseModel
from src.state import VideoGenerationState
from src.nodes.consultation.consultation_pipeline import ConsultationPipelineNode

app = FastAPI(
    title="Consultation Video API",
    version="1.0.0"
)
logger = logging.getLogger(__name__)
LATEST_CONSULTATION_VIDEOS: dict[str, str] = {}
S3_BUCKET = "tech-learn-state"
s3_client = boto3.client("s3")

class ConsultationRequest(BaseModel):
    user_id: str


@app.get("/")
def health():
    return {
        "status": "healthy",
        "service": "consultation-api"
    }


@app.post("/consultation-video")
def generate_consultation(req: ConsultationRequest):

    try:

        state = VideoGenerationState(
            session_id=req.user_id,
            topic="Consultation",
            target_language="english",
            tts_gender="female",
            optional_params={
                "script_type": "consultation"
            }
        )

        node = ConsultationPipelineNode()

        result = node.generate_consultation_video(state)

        video_value = result.slide_video_path
        local_video_path = None
        if isinstance(video_value, dict):
            local_video_path = video_value.get("english")
            if local_video_path is None and video_value:
                local_video_path = next(iter(video_value.values()))
        elif isinstance(video_value, str):
            local_video_path = video_value

        if local_video_path and os.path.exists(local_video_path):
            LATEST_CONSULTATION_VIDEOS[req.user_id] = local_video_path

        return {
            "status": result.status,
            "user_id": req.user_id,
            "video_url": result.slide_video_path,
            "download_url": f"/consultation-video/download/{req.user_id}" if local_video_path else None,
            "error": result.error
        }

    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=str(e)
        )


@app.get("/consultation-video/download/{user_id}")
def download_consultation_video(user_id: str):

    s3_key = (
        f"video_states/{user_id}/"
        f"consultation/english/consultation_video.mp4"
    )

    # Try S3 first (source of truth)
    try:
        s3_client.head_object(
            Bucket=S3_BUCKET,
            Key=s3_key
        )

        presigned_url = s3_client.generate_presigned_url(
            "get_object",
            Params={
                "Bucket": S3_BUCKET,
                "Key": s3_key
            },
            ExpiresIn=3600
        )

        logger.info(
            f"[DOWNLOAD] Serving consultation video from S3 | "
            f"user_id={user_id} | key={s3_key}"
        )

        return RedirectResponse(
            url=presigned_url,
            status_code=302
        )

    except Exception as e:
        logger.warning(
            f"[DOWNLOAD] S3 lookup failed | "
            f"user_id={user_id} | key={s3_key} | error={str(e)}"
        )

    # Fallback to local file
    video_path = LATEST_CONSULTATION_VIDEOS.get(user_id)

    if video_path and os.path.exists(video_path):

        logger.info(
            f"[DOWNLOAD] Serving consultation video from local cache | "
            f"user_id={user_id} | path={video_path}"
        )

        return FileResponse(
            path=video_path,
            media_type="video/mp4",
            filename=f"{user_id}_consultation_video.mp4"
        )

    logger.error(
        f"[DOWNLOAD] Consultation video not found anywhere | "
        f"user_id={user_id}"
    )

    raise HTTPException(
        status_code=404,
        detail=(
            f"No consultation video found for user_id '{user_id}'. "
            f"Video was not found in S3 and no local copy exists. "
            f"Generate the consultation video first."
        )
    )