"""Configuration files and utilities for mini-SWE-agent."""

import json

import os

from pathlib import Path

import yaml

builtin_config_dir = Path(__file__).parent

def get_config_path(config_spec: str | Path) -> Path:

    """Get the path to a config file."""

    config_spec = Path(config_spec)

    if config_spec.suffix != ".yaml":

        config_spec = config_spec.with_suffix(".yaml")

    candidates = [

        Path(config_spec),

        Path(os.getenv("MSWEA_CONFIG_DIR", ".")) / config_spec,

        builtin_config_dir / config_spec,

        builtin_config_dir / "extra" / config_spec,

        builtin_config_dir / "benchmarks" / config_spec,

    ]

    for candidate in candidates:

        if candidate.exists():

            return candidate

    raise FileNotFoundError(f"Could not find config file for {config_spec} (tried: {candidates})")

def _key_value_spec_to_nested_dict(config_spec: str) -> dict:

    """Interpret key-value specs from the command line.

    Example:

    "model.model_name=anthropic/claude-sonnet-4-5-20250929"   ->

    {"model": {"model_name": "anthropic/claude-sonnet-4-5-20250929"}}

    """

    key, value = config_spec.split("=", 1)

    try:

        value = json.loads(value)

    except json.JSONDecodeError:

        pass

    keys = key.split(".")

    result = {}

    current = result

    for k in keys[:-1]:

        current[k] = {}

        current = current[k]

    current[keys[-1]] = value

    return result

def get_config_from_spec(config_spec: str | Path) -> dict:

    """Get a config from a config spec."""

    if isinstance(config_spec, str) and "=" in config_spec:

        return _key_value_spec_to_nested_dict(config_spec)

    path = get_config_path(config_spec)

    return yaml.safe_load(path.read_text())

__all__ = ["builtin_config_dir", "get_config_path", "get_config_from_spec", "_key_value_spec_to_nested_dict"]