"""Shared configuration loader for bootstrap and CI."""

import re
from pathlib import Path
from typing import NamedTuple

import tomllib


class BuildConfig(NamedTuple):
    """Build configuration extracted from pyproject.toml."""

    alfred_version: str
    python_version: str
    python_version_short: str
    runner: str
    image_name: str
    service_name: str
    librechat_version: str
    rag_version: str


def extract_python_version(version_string: str) -> tuple[str, str]:
    """
    Extract Python version from poetry dependency string.
    Examples:
        "==3.14.2" -> ("3.14.2", "3.14")
        "^3.14.2" -> ("3.14.2", "3.14")
        "~3.14.2" -> ("3.14.2", "3.14")
        "3.14.2" -> ("3.14.2", "3.14")
    """
    clean_version = re.sub(r"^[=^~><]+", "", version_string.strip())
    parts = clean_version.split(".")

    if len(parts) >= 2:
        full_version = clean_version
        short_version = f"{parts[0]}.{parts[1]}"
        return full_version, short_version
    else:
        raise ValueError(f"Invalid Python version format: {version_string}")


def load_build_config(base_dir: Path | None = None) -> BuildConfig:
    """Load build configuration from pyproject.toml."""
    if base_dir is None:
        base_dir = Path(__file__).resolve().parent.parent

    toml_path = base_dir / "pyproject.toml"
    if not toml_path.exists():
        raise FileNotFoundError(f"pyproject.toml not found: {toml_path}")

    with open(toml_path, "rb") as f:
        data = tomllib.load(f)
        settings_keys = data["tool"]["alfred"]["settings"]
        dependencies = data["tool"]["poetry"]["dependencies"]
        alfred_version = data["tool"]["poetry"]["version"]

    python_version_full, python_version_short = extract_python_version(
        dependencies["python"]
    )

    return BuildConfig(
        alfred_version=alfred_version,
        python_version=python_version_full,
        python_version_short=python_version_short,
        runner=settings_keys["runner"],
        image_name=settings_keys["image_name"],
        service_name=settings_keys["service_name"],
        librechat_version=settings_keys["librechat_version"],
        rag_version=settings_keys["rag_version"],
    )


def write_env_make(config: BuildConfig, base_dir: Path | None = None) -> None:
    """Write .env.make file for Makefile."""
    if base_dir is None:
        base_dir = Path(__file__).resolve().parent.parent

    env_make_path = base_dir / ".env.make"
    with open(env_make_path, "w", encoding="utf-8") as f:
        f.write("# Auto-generated from pyproject.toml\n")
        f.write(f"export ALFRED_VERSION={config.alfred_version}\n")
        f.write(f"export PYTHON_VERSION={config.python_version}\n")
        f.write(f"export PYTHON_VERSION_SHORT={config.python_version_short}\n")
        f.write(f"export RUNNER={config.runner}\n")
        f.write(f"export IMAGE_NAME={config.image_name}\n")
        f.write(f"export SERVICE_NAME={config.service_name}\n")
        f.write(f"export LIBRECHAT_VERSION={config.librechat_version}\n")
        f.write(f"export RAG_VERSION={config.rag_version}\n")