#!/usr/bin/env python3
"""The project folder is mounted by the session, not by the image.

    python3 tests/test_vm_share_mount.py

WHY

The share is one virtiofs tag. The image built by the autoinstall carries
an fstab line for it; an image installed by hand does not, and the
failure that produces is the worst shape there is - the machine boots,
the agent runs its commands, files are written, the host commits an empty
directory, and the Gitea repository is simply empty. No error anywhere.

So the session mounts it over the guest channel every time, and these
cases cover the three things that has to get right: do nothing when there
is no share, do nothing on Windows (where the mount is WinFsp's job and
there is no command to run from here), and fail LOUDLY rather than carry
on when the mount does not take.
"""

import os
import sys

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "vm", "vmd"))

import session as S  # noqa: E402

FAILS: list[str] = []


def check(label: str, condition: bool, detail: str = "") -> None:
    if condition:
        print(f"ok    {label}")
    else:
        FAILS.append(f"{label}: {detail}")
        print(f"FAIL  {label}\n      {detail}")


class FakeGuest:
    def __init__(self, result):
        self.result = result
        self.scripts: list[str] = []

    def __enter__(self):
        return self

    def __exit__(self, *_exc):
        return False

    def shell(self, script, timeout_s=0):
        self.scripts.append(script)
        return self.result


class FakeSession:
    def __init__(self, os_name="ubuntu", share="/Pool/vmprojects/p", result=None):
        self.os_name = os_name
        self.share = share
        self._guest = FakeGuest(result or {"exit_code": 0, "stdout": "", "stderr": ""})

    def guest(self, timeout=0):
        return self._guest


# --- nothing to mount ---------------------------------------------------
s = FakeSession(share=None)
S._mount_share(s)
check("no share: nothing is run in the guest", s._guest.scripts == [],
      f"ran {s._guest.scripts}")

# --- Windows ------------------------------------------------------------
s = FakeSession(os_name="windows")
S._mount_share(s)
check("windows: no linux mount command is sent", s._guest.scripts == [],
      f"ran {s._guest.scripts}")

# --- the normal case ----------------------------------------------------
s = FakeSession()
S._mount_share(s)
script = s._guest.scripts[0] if s._guest.scripts else ""
check("ubuntu: the share is mounted", "mount -t virtiofs project /mnt/project" in script,
      f"script was: {script!r}")
check("and the mountpoint is created first", "mkdir -p /mnt/project" in script, script)
# Idempotence is not a nicety here: an image that DOES carry the fstab
# line is already mounted, and a second mount over the top would hide it.
check("and an existing mount is left alone", "mountpoint -q /mnt/project ||" in script, script)
check("and the result is checked rather than assumed",
      script.strip().endswith("mountpoint -q /mnt/project"), script)

# --- the failure that must not be silent --------------------------------
s = FakeSession(result={"exit_code": 32, "stdout": "",
                        "stderr": "unknown filesystem type 'virtiofs'"})
try:
    S._mount_share(s)
    check("a failed mount stops the session", False, "it carried on regardless")
except S.SessionError as exc:
    text = str(exc)
    check("a failed mount stops the session", True)
    check("and says what would have been lost",
          "would be kept" in text or "nothing written" in text, text)
    check("and quotes what the guest actually said", "virtiofs" in text, text)

print()
if FAILS:
    print(f"FAILED {len(FAILS)}")
    raise SystemExit(1)
print("the project folder is mounted by the session, and loudly if not")