from __future__ import annotations

from dataclasses import dataclass, field
from pathlib import Path


@dataclass
class CommandSpec:
    command: list[str]
    cwd: Path
    description: str = ""
    env: dict[str, str] = field(default_factory=dict)
    stdin_text: str | None = None


TaskFactory = callable


def conda_python(env_name: str, script: Path, *args: object) -> list[str]:
    return ["conda", "run", "-n", env_name, "python", str(script), *[str(a) for a in args]]


def python(script: Path, *args: object) -> list[str]:
    return ["python", str(script), *[str(a) for a in args]]


def bash(script: Path, *args: object) -> list[str]:
    return ["bash", str(script), *[str(a) for a in args]]


def option(params: dict, name: str, default=None):
    value = params.get(name, default)
    return value


def required(params: dict, name: str):
    if name not in params or params[name] in (None, ""):
        raise ValueError(f"missing required parameter: {name}")
    return params[name]


def append_flag(args: list[str], flag: str, value):
    if value not in (None, ""):
        args.extend([flag, str(value)])