import argparse
import asyncio
import sys

from .client import GeminiClient
from .models import list_models
from .types import GeminiOptions


def parse_args():
    p = argparse.ArgumentParser(prog="gemini", description="Query Gemini via CLI")
    p.add_argument("prompt", nargs="?", help="Prompt to send (reads stdin if omitted)")
    p.add_argument("-m", "--model", default="gemini-2.5-pro", help="Model name")
    p.add_argument("-c", "--credentials", default=None, help="Path to oauth_creds.json")
    p.add_argument("--no-stream", action="store_true", help="Non-streaming mode")
    p.add_argument(
        "--thinking",
        type=int,
        default=None,
        metavar="BUDGET",
        help="Enable thinking mode with given token budget",
    )
    p.add_argument("--list-models", action="store_true", help="List available models and exit")
    return p.parse_args()


async def run(args):
    prompt = args.prompt or sys.stdin.read().strip()
    if not prompt:
        print("Error: no prompt provided", file=sys.stderr)
        sys.exit(1)

    opts = GeminiOptions(
        model=args.model,
        thinking_budget=args.thinking,
    )

    async with GeminiClient(options=opts, credentials_path=args.credentials) as client:
        if args.no_stream:
            response = await client.send_message(prompt)
            print(response.text)
        else:
            async for chunk in client.send_message_stream(prompt):
                if chunk.text_delta:
                    print(chunk.text_delta, end="", flush=True)
            print()


def main():
    args = parse_args()
    if args.list_models:
        for m in list_models():
            tag = " [default]" if m.is_default else " [preview]" if m.is_preview else ""
            print(f"{m.name}{tag}")
        return
    asyncio.run(run(args))


if __name__ == "__main__":
    main()