# app.py
from app.gradio_app import build_demo
from models.tts_router import cleanup_old_audio

import os
import huggingface_hub

# ----------------------------
# Model bootstrap (unchanged)
# ----------------------------
def ensure_model():
    model_path = os.getenv("LLAMACPP_MODEL_PATH")
    repo_id    = os.getenv("HF_MODEL_REPO")
    file_name  = os.getenv("HF_MODEL_FILE") or (os.path.basename(model_path) if model_path else None)

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

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

    os.makedirs(os.path.dirname(model_path), exist_ok=True)
    print(f"[MODEL] Downloading {file_name} from {repo_id} …")
    local_path = huggingface_hub.hf_hub_download(
        repo_id=repo_id,
        filename=file_name,
        local_dir=os.path.dirname(model_path),
        local_dir_use_symlinks=False,
    )
    print(f"[MODEL] Saved at {local_path}")
    return local_path


# ----------------------------------------
# TTS bootstrap: prefer piper, safe fallback
# ----------------------------------------
def ensure_tts_engine():
    """
    If TTS_ENGINE == 'piper' but we cannot find a working binary,
    automatically fall back to 'pyttsx3' so the Space still speaks.
    """
    engine = os.getenv("TTS_ENGINE", "pyttsx3").strip().lower()
    if engine != "piper":
        print(f"[TTS] Using engine: {engine}")
        return

    # Check for an executable piper binary
    piper_bin = os.getenv("PIPER_BIN", "piper")
    piper_model = os.getenv("PIPER_MODEL")  # should be set if you want piper
    def _is_exec(path):
        return os.path.isfile(path) and os.access(path, os.X_OK)

    found = False
    if os.path.isabs(piper_bin) and _is_exec(piper_bin):
        found = True
    else:
        # try PATH
        from shutil import which
        if which(piper_bin) is not None:
            found = True

    if not found or not piper_model or not os.path.exists(piper_model):
        # Fall back
        msg = []
        if not found:
            msg.append(f"piper binary '{piper_bin}' not found")
        if not piper_model:
            msg.append("PIPER_MODEL not set")
        elif not os.path.exists(piper_model):
            msg.append(f"PIPER_MODEL not found on disk: {piper_model}")
        print("[TTS] Piper not available -> falling back to pyttsx3. (" + "; ".join(msg) + ")")
        os.environ["TTS_ENGINE"] = "pyttsx3"
    else:
        print(f"[TTS] Using Piper: bin={piper_bin}, model={piper_model}")


def main():
    # Clean up old TTS files on boot
    cleanup_old_audio(keep_latest=None)

    # Download model if needed
    ensure_model()

    # Make TTS robust on Spaces
    ensure_tts_engine()

    demo = build_demo()
    # Let HF handle host/port; expose a public link
    demo.launch(share=True)


if __name__ == "__main__":
    main()