# app.py
from __future__ import annotations
import os
from typing import Optional

from app.gradio_app import build_demo
from models.tts_router import cleanup_old_audio
from utils.config import get_settings

import huggingface_hub


def ensure_model() -> str:
    """
    Ensure a local GGUF exists:
      - Reads settings from .env via pydantic (get_settings()).
      - If the file at LLAMACPP_MODEL_PATH doesn't exist, download from HF_MODEL_REPO/HF_MODEL_FILE.
      - HF_MODEL_FILE is optional; if missing, we use basename(LLAMACPP_MODEL_PATH).
      - The file is saved exactly at LLAMACPP_MODEL_PATH (e.g., models/<file>.gguf).
    """
    s = get_settings()  # <- loads .env
    model_path: Optional[str] = getattr(s, "LLAMACPP_MODEL_PATH", None) or os.getenv("LLAMACPP_MODEL_PATH")
    repo_id: Optional[str]   = getattr(s, "HF_MODEL_REPO", None)        or os.getenv("HF_MODEL_REPO")
    file_name: Optional[str] = getattr(s, "HF_MODEL_FILE", None)        or os.getenv("HF_MODEL_FILE")

    if not model_path or not repo_id:
        raise RuntimeError(
            "Missing config: set LLAMACPP_MODEL_PATH and HF_MODEL_REPO in .env "
            "(optionally HF_MODEL_FILE)."
        )

    # Where/what to download
    if not file_name:
        file_name = os.path.basename(model_path)

    # Already present?
    if os.path.exists(model_path):
        print(f"[MODEL] Found existing model at {model_path}")
        return model_path

    # Make sure models/ exists
    os.makedirs(os.path.dirname(model_path), exist_ok=True)

    print(f"[MODEL] Downloading {file_name} from {repo_id} → {model_path}")
    # Download into a temp cache, then copy/symlink into our desired path
    local_cached = huggingface_hub.hf_hub_download(
        repo_id=repo_id,
        filename=file_name,
        local_dir=os.path.dirname(model_path),      # ensure it lands under models/
        local_dir_use_symlinks=False
    )

    # hf_hub_download already placed it in local_dir; ensure final path matches model_path
    if os.path.abspath(local_cached) != os.path.abspath(model_path):
        # If HF wrote it to a different name/path, copy/rename
        import shutil
        shutil.move(local_cached, model_path)

    print(f"[MODEL] Ready at {model_path}")
    return model_path


def main():
    # Clean old TTS files
    cleanup_old_audio(keep_latest=None)
    # Ensure the local model is present (downloads if missing)
    ensure_model()

    demo = build_demo()
    # On HF Spaces, share=True is fine; server host/port are managed by Spaces
    demo.launch(share=True)


if __name__ == "__main__":
    main()