from __future__ import annotations

import json
import os
from typing import Any, Dict

from .registry import ToolRegistry


def _s3_client():
    try:
        import boto3  # type: ignore
    except Exception as e:
        return None, f"boto3 not available: {e}"
    try:
        s3 = boto3.client(
            "s3",
            endpoint_url=os.getenv("AWS_ENDPOINT_URL"),
            region_name=os.getenv("AWS_DEFAULT_REGION", "us-east-1"),
        )
        return s3, None
    except Exception as e:
        return None, str(e)


def t_s3_list(args: Dict[str, Any]) -> str:
    bucket = args.get("bucket")
    prefix = args.get("prefix", "")
    s3, err = _s3_client()
    if err:
        return json.dumps({"error": err})
    if not bucket:
        return json.dumps({"error": "bucket required"})
    try:
        resp = s3.list_objects_v2(Bucket=bucket, Prefix=prefix)  # type: ignore
        items = [o["Key"] for o in resp.get("Contents", [])]
        return json.dumps({"items": items})
    except Exception as e:
        return json.dumps({"error": str(e)})


def register_tools(reg: ToolRegistry) -> None:
    reg.register(
        name="s3_list",
        description="List objects from S3/R2 compatible storage.",
        parameters={"type": "object", "properties": {"bucket": {"type": "string"}, "prefix": {"type": "string"}}, "required": ["bucket"]},
        handler=t_s3_list,
    )