"""Example FastAPI server for llama.cpp.

To run this example:

```bash
pip install fastapi uvicorn sse-starlette pydantic-settings
export MODEL=../models/7B/...
```

Then run:
```
uvicorn llama_cpp.server.app:app --reload
```

or

```
python3 -m llama_cpp.server
```

Then visit http://localhost:8000/docs to see the interactive API docs.

"""
import os
import argparse
from typing import Literal, Union

import uvicorn

from llama_cpp.server.app import create_app, Settings

def get_non_none_base_types(annotation):
    if not hasattr(annotation, "__args__"):
        return annotation
    return [arg for arg in annotation.__args__ if arg is not type(None)][0]

def get_base_type(annotation):
    if getattr(annotation, '__origin__', None) is Literal:
        return type(annotation.__args__[0])
    elif getattr(annotation, '__origin__', None) is Union:
        non_optional_args = [arg for arg in annotation.__args__ if arg is not type(None)]
        if non_optional_args:
            return get_base_type(non_optional_args[0])
    else:
        return annotation

if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    for name, field in Settings.model_fields.items():
        description = field.description
        if field.default is not None and description is not None:
            description += f" (default: {field.default})"
        parser.add_argument(
            f"--{name}",
            dest=name,
            type=get_base_type(field.annotation) if field.annotation is not None else str,
            help=description,
        )

    args = parser.parse_args()
    settings = Settings(**{k: v for k, v in vars(args).items() if v is not None})
    app = create_app(settings=settings)

    uvicorn.run(
        app, host=os.getenv("HOST", settings.host), port=int(os.getenv("PORT", settings.port))
    )