"""custom-html — BACKUP overlay (Phase 1d, DG4): seed a known state, back it up (assert artifact),
then mutate so the RESTORE overlay (test_restore.py) can prove the backed-up state returns. Runs on
the shared deployment; the marker it leaves ("mutated") persists for the restore tier.

Reads the marker via `exec_in_app` (the file in the volume), NOT http: backup/restore preserve the
VOLUME, and reading it directly is immune to the serving/container-routing race right after
backup-bot-two cycles the app container (HTTP briefly served empty). Serving is proven separately by
the install/upgrade tiers' assert_serving."""

import os
import sys

sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "runner"))
from harness import generic, lifecycle  # noqa: E402

MARKER_PATH = "/usr/share/nginx/html/ci-marker.txt"


def _marker(domain: str) -> str:
    return lifecycle.exec_in_app(domain, ["cat", MARKER_PATH]).strip()


def test_backup_captures_state(live_app, meta):
    domain = live_app
    # 1) establish a known original state, then back it up (reuse the generic op: backup + assert a
    #    snapshot artifact was produced)
    lifecycle.exec_in_app(domain, ["sh", "-c", f"echo original > {MARKER_PATH}"])
    assert _marker(domain) == "original"
    snap = generic.do_backup(domain)
    assert snap, "backup produced no snapshot artifact"

    # 2) mutate state so a successful restore is observable (diverge from the backup)
    lifecycle.exec_in_app(domain, ["sh", "-c", f"echo mutated > {MARKER_PATH}"])
    assert _marker(domain) == "mutated"