from __future__ import annotations

import subprocess
import typing as t

from mercurial import error as hgerr
from mercurial import registrar

from . import _export as xp

if t.TYPE_CHECKING:
    import mercurial.interfaces.repository as hgrepo
    import mercurial.ui as hgui

cmdtable: dict[bytes, object] = {}
_command = registrar.command(cmdtable)


def _not_git() -> hgerr.StateError:
    return hgerr.StateError(
        b'Git is not enabled for this repository.',
        hint=b'The server administrator should enable the ``hggit`` extension '
             b'and run ``hg git-export`` to enable Git access.',
    )


def _maybe(flag: bytes, include: bool) -> tuple[bytes, ...]:
    return (flag,) if include else ()


@_command(
    b'git-upload-pack',
    [
        *(
            (b'', opt, False, b'flag passed to git upload-pack')
            for opt in (
                b'strict',
                b'no-strict',
                b'stateless-rpc',
                b'advertise-refs',
            )
        ),
        (b'', b'timeout', -1, b'flag passed to git upload-pack'),
    ],
    helpcategory=b'import',
    intents=(b'readonly',),
)
def _git_upload_pack(
    ui: hgui.ui,
    repo: hgrepo.IRepo,
    *,
    strict: bool,
    no_strict: bool,
    stateless_rpc: bool,
    advertise_refs: bool,
    timeout: int,
) -> int:
    """Server-side handler for ``git pull``/``git clone``."""
    if not xp.is_gitty(repo):
        raise _not_git()
    timeout_flag = (
        (b'--timeout=' + str(timeout).encode(),) if timeout != -1 else ()
    )
    upload_pack = ui.configlist(
        b'hggit-serve', b'upload-pack', default=(b'git', b'upload-pack')
    )
    return subprocess.call(
        (
            *upload_pack,
            *_maybe(b'--strict', strict),
            *_maybe(b'--no-strict', no_strict),
            *_maybe(b'--stateless-rpc', stateless_rpc),
            *_maybe(b'--advertise_refs', advertise_refs),
            *timeout_flag,
            repo.githandler.gitdir,
        ),
        close_fds=True,
    )


@_command(
    b'git-receive-pack',
    [
        (b'', b'skip-connectivity-check', False, b'passed to git receive-pack'),
    ],
    helpcategory=b'import',
)
def _git_receive_pack(
    ui: hgui.ui, repo: hgrepo.IRepo, *, skip_connectivity_check: bool
) -> int:
    """Server-side handler for ``git push``."""
    if not xp.is_gitty(repo):
        raise _not_git()
    receive_pack = ui.configlist(
        b'hggit-serve', b'receive-pack', default=(b'git', b'receive-pack')
    )
    try:
        subprocess.check_call(
            (
                *receive_pack,
                *_maybe(b'--skip-connectivity-check', skip_connectivity_check),
                repo.githandler.gitdir,
            ),
            close_fds=True,
        )
    except subprocess.CalledProcessError as cpe:
        return cpe.returncode
    xp.import_all(repo, b'git-receive-pack')
    return 0


__all__ = ('cmdtable',)