#!/usr/bin/env bats
# tests/lifecycle/bats/use-quadlet-backends-install.bats
#
# Validates the post-condition of Phase 3.2's `use_quadlet_backends`
# install path. When the orchestrator routed at least one backend
# install through `install_via_quadlet`, this suite asserts that the
# resulting state has the four properties the Phase 3 design promises:
#
#   1. A `.container` unit file exists in ~/.config/containers/systemd/
#      and is well-formed (required sections + directives).
#   2. The corresponding `.service` is active under `systemctl --user`.
#   3. The container is in `podman ps` (running).
#   4. The container's cgroup is under `user.slice/...`, NOT under
#      `archipelago.service` — proving FM3 (cgroup cascade SIGKILL on
#      archipelago restart) is structurally fixed for that container.
#
# Auto-skips if no Quadlet-managed backend exists yet — so it runs as a
# no-op on nodes where `use_quadlet_backends` is still false (today's
# default), and turns into a hard regression gate as soon as anyone
# flips the flag and reinstalls.
#
# Run on a node with rootless podman + systemd-user (every alpha-fleet
# box). No env vars required for the read-only checks. The cleanup
# section at the bottom is gated by ARCHY_ALLOW_DESTRUCTIVE=1.

quadlet_dir() {
  echo "${XDG_CONFIG_HOME:-$HOME/.config}/containers/systemd"
}

# List Quadlet `.container` units that correspond to backend containers
# (i.e., NOT companions like archy-*-ui, which already shipped via Quadlet
# in v1.7.41 and have their own coverage in companion-survives-archipelago-
# restart.bats). Echoes one container name per line; empty if none found.
backend_quadlet_units() {
  local d
  d="$(quadlet_dir)"
  [[ -d "$d" ]] || return 0
  # Strip the .container extension; filter out archy-*-ui companions.
  for f in "$d"/*.container; do
    [[ -e "$f" ]] || continue
    local name
    name="$(basename "$f" .container)"
    [[ "$name" =~ ^archy-.*-ui$ ]] && continue
    echo "$name"
  done
}

# Read the cgroup path of a running container's main process. For
# rootless podman the conmon-run target lands the container's pid1 in
# the cgroup that owns its supervising .service.
container_cgroup_path() {
  local name="$1"
  local pid
  pid="$(podman inspect --format '{{.State.Pid}}' "$name" 2>/dev/null)"
  [[ -n "$pid" && "$pid" != "0" ]] || return 1
  # cgroup v2 line: "0::/path/to/cgroup"
  awk -F: '$1=="0"{print $3}' "/proc/$pid/cgroup" 2>/dev/null
}

# Per-test gate. Each @test calls this so the suite is a clean no-op on
# nodes where use_quadlet_backends is still false (today's default) —
# bats doesn't propagate setup-level skip semantics across @test blocks.
require_quadlet_backends() {
  local count
  count="$(backend_quadlet_units | wc -l)"
  (( count > 0 )) || skip "no backend .container units in $(quadlet_dir) — use_quadlet_backends not enabled or no backends installed"
}

@test "Quadlet unit dir exists or is plausibly creatable" {
  local d
  d="$(quadlet_dir)"
  # Either it already exists, or its parent does (so quadlet can mkdir it).
  [[ -d "$d" ]] || [[ -d "$(dirname "$d")" ]] \
    || skip "no XDG_CONFIG_HOME and no \$HOME/.config — not a desktop-style host"
}

@test "each backend Quadlet unit has the required sections + directives" {
  require_quadlet_backends
  local d
  d="$(quadlet_dir)"
  while read -r name; do
    [[ -z "$name" ]] && continue
    local body
    body="$(<"$d/$name.container")"
    # [Container] section + Image=
    [[ "$body" == *"[Container]"* ]]   || fail "$name: missing [Container] section"
    [[ "$body" == *"Image="*       ]]  || fail "$name: missing Image= directive"
    # [Service] section with the Phase 3.2 backend invariant: Restart=on-failure.
    # Companions use Restart=always; backends use on-failure so an operator-issued
    # `systemctl stop` actually stays stopped.
    [[ "$body" == *"[Service]"*       ]] || fail "$name: missing [Service] section"
    [[ "$body" == *"Restart=on-failure"* ]] \
      || fail "$name: backend unit must use Restart=on-failure (got companion-style Restart=always)"
    # [Install] section so `systemctl --user enable` is well-defined.
    [[ "$body" == *"[Install]"* ]]  || fail "$name: missing [Install] section"
    [[ "$body" == *"WantedBy="*  ]] || fail "$name: missing WantedBy= in [Install]"
  done < <(backend_quadlet_units)
}

@test "Phase 3.4: any unit emitting HealthCmd= also emits Notify=healthy" {
  require_quadlet_backends
  local d
  d="$(quadlet_dir)"
  while read -r name; do
    [[ -z "$name" ]] && continue
    local body
    body="$(<"$d/$name.container")"
    if [[ "$body" == *"HealthCmd="* ]]; then
      [[ "$body" == *"Notify=healthy"* ]] \
        || fail "$name: HealthCmd= present but Notify=healthy missing — systemctl start won't gate on health"
    fi
  done < <(backend_quadlet_units)
}

@test "every backend Quadlet unit's .service is active in systemctl --user" {
  require_quadlet_backends
  while read -r name; do
    [[ -z "$name" ]] && continue
    run systemctl --user is-active "$name.service"
    [[ "$status" -eq 0 ]] || fail "$name.service is '$output' — expected 'active'"
  done < <(backend_quadlet_units)
}

@test "every backend Quadlet unit has a running podman container" {
  require_quadlet_backends
  while read -r name; do
    [[ -z "$name" ]] && continue
    run sh -c "podman inspect --format '{{.State.Running}}' '$name'"
    [[ "$status" -eq 0 ]] || fail "$name not present in podman"
    [[ "$output" == "true" ]] || fail "$name container exists but not running (state=$output)"
  done < <(backend_quadlet_units)
}

@test "FM3 fix: backend cgroup is under user.slice, not archipelago.service" {
  require_quadlet_backends
  # The whole point of Phase 3 — verify the kernel-level invariant.
  while read -r name; do
    [[ -z "$name" ]] && continue
    local cg
    cg="$(container_cgroup_path "$name")" || skip "$name has no readable PID; container may have crashed mid-test"
    [[ -n "$cg" ]] || fail "$name: empty cgroup path"
    # Acceptable: anything under user.slice (rootless podman lands here when
    # quadlet-managed). Forbidden: anything under archipelago.service's tree.
    [[ "$cg" == *"user.slice"* ]] \
      || fail "$name: cgroup '$cg' is not under user.slice — FM3 cascade still possible"
    [[ "$cg" != *"archipelago.service"* ]] \
      || fail "$name: cgroup '$cg' is under archipelago.service — Phase 3 promise broken"
  done < <(backend_quadlet_units)
}