from __future__ import annotations

import contextlib
import os
import sys
from typing import Generator
from typing import Sequence

from pre_commit import lang_base
from pre_commit.envcontext import envcontext
from pre_commit.envcontext import PatchesT
from pre_commit.envcontext import Var
from pre_commit.prefix import Prefix
from pre_commit.util import cmd_output

ENVIRONMENT_DIR = "lua_env"
get_default_version = lang_base.basic_get_default_version
health_check = lang_base.basic_health_check
run_hook = lang_base.basic_run_hook


def _get_lua_version() -> str:  # pragma: win32 no cover
    """Get the Lua version used in file paths."""
    _, stdout, _ = cmd_output("luarocks", "config", "--lua-ver")
    return stdout.strip()


def get_env_patch(d: str) -> PatchesT:  # pragma: win32 no cover
    version = _get_lua_version()
    so_ext = "dll" if sys.platform == "win32" else "so"
    return (
        ("PATH", (os.path.join(d, "bin"), os.pathsep, Var("PATH"))),
        (
            "LUA_PATH",
            (
                os.path.join(d, "share", "lua", version, "?.lua;"),
                os.path.join(d, "share", "lua", version, "?", "init.lua;;"),
            ),
        ),
        (
            "LUA_CPATH",
            (os.path.join(d, "lib", "lua", version, f"?.{so_ext};;"),),
        ),
    )


@contextlib.contextmanager  # pragma: win32 no cover
def in_env(prefix: Prefix, version: str) -> Generator[None, None, None]:
    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
    with envcontext(get_env_patch(envdir)):
        yield


def install_environment(
    prefix: Prefix,
    version: str,
    additional_dependencies: Sequence[str],
) -> None:  # pragma: win32 no cover
    lang_base.assert_version_default("lua", version)

    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
    with in_env(prefix, version):
        # luarocks doesn't bootstrap a tree prior to installing
        # so ensure the directory exists.
        os.makedirs(envdir, exist_ok=True)

        # Older luarocks (e.g., 2.4.2) expect the rockspec as an arg
        for rockspec in prefix.star(".rockspec"):
            make_cmd = ("luarocks", "--tree", envdir, "make", rockspec)
            lang_base.setup_cmd(prefix, make_cmd)

        # luarocks can't install multiple packages at once
        # so install them individually.
        for dependency in additional_dependencies:
            cmd = ("luarocks", "--tree", envdir, "install", dependency)
            lang_base.setup_cmd(prefix, cmd)
