#!/usr/bin/env bash

# What closing the lid does.
#
# One sentence: closing the lid should suspend, unless there is an external
# monitor, in which case the machine is docked and should keep working.
#
# The mechanism is a logind `handle-lid-switch` inhibitor held while an
# external display is connected, rather than a lid watcher of Panama's own.
# That choice is the thing most worth pinning, because the obvious alternative
# fails in the dangerous direction: a drop-in setting HandleLidSwitch=ignore
# plus a watcher that dies leaves a laptop whose lid does nothing at all, being
# carried out of a building. An inhibitor that dies gives back logind's
# default, which is merely an annoying suspend at a desk.
#
# So this asserts, in order of how much it would cost to get wrong:
#
#   1. No logind drop-in is shipped. Panama never takes the lid over.
#   2. A machine with no reason for an inhibitor holds none: a desktop, and an
#      undocked laptop that should suspend normally.
#   3. A docked laptop holds one, and it is the right kind.
#   4. Locking on the way down is not this code's job -- hypridle's
#      before_sleep_cmd already does it -- and must not be quietly duplicated.
#   5. Opening the lid restores the panel as it was CONFIGURED, not as a
#      four-key approximation of it. `open` used to emit a rule carrying
#      output/mode/position/scale and nothing else, and a Hyprland monitor rule
#      replaces the previous rule for that output whole -- so a docked laptop
#      whose internal panel had been set to 10-bit, wide gamut, rotated, or
#      placed at a particular position lost every one of those the first time
#      the lid was closed and reopened. Silently, and only on a machine with a
#      lid, which is the combination that keeps a bug alive.
#
# Driven with stubbed predicates, and for (5) a stubbed `hyprctl` that records
# the rule instead of applying it. The end-to-end behavior of a real lid needs a
# machine with a lid; see the header of the helper.

set -uo pipefail

repo_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
helper="$repo_dir/config/dot/quickshell/scripts/panama-lid"
service="$repo_dir/config/dot/quickshell/services/LidPolicy.qml"
shell_qml="$repo_dir/config/dot/quickshell/shell.qml"
hypridle="$repo_dir/config/dot/hypr/hypridle.conf"

findings=()
note() { findings+=("$1"); }

[[ -x "$helper" ]] || { printf 'lid contract: %s is not executable\n' "$helper" >&2; exit 1; }

work="$(mktemp -d)"
trap 'rm -rf "$work"' EXIT
calls="$work/calls"
fake="$work/fake"
mkdir -p "$fake/bin"

# ── 1. Panama never takes the lid over ───────────────────────────────────────

# Specifically the LID. Other keys may be configured there -- the power-key
# drop-in is deliberate policy with a compositor bind behind it -- but a
# HandleLidSwitch line would replace the inhibitor design this file protects.
if compgen -G "$repo_dir/config/copy/etc/systemd/logind.conf.d/*" >/dev/null 2>&1 \
    && sed 's/#.*//' "$repo_dir"/config/copy/etc/systemd/logind.conf.d/* | grep -q 'HandleLidSwitch'; then
    note 'a logind drop-in sets HandleLidSwitch; the inhibitor approach exists so the lid is never left doing nothing'
fi
# Comments are stripped first: these files explain at length what they
# deliberately do NOT do, and prose naming HandleLidSwitch or lock-session is
# documentation rather than behavior.
uncommented() { grep -rhv '^[[:space:]]*#' "$@" 2>/dev/null; }

uncommented "$repo_dir/config" | grep -q 'HandleLidSwitch' \
    && note 'something sets HandleLidSwitch, which takes the lid away from logind'

# ── The stubs ────────────────────────────────────────────────────────────────

# panama-hw answers whatever this fixture says. $1 laptop, $2 external monitor,
# as exit codes: 0 yes, 1 no.
stub_hw() {
    cat >"$fake/bin/panama-hw" <<STUB
#!/usr/bin/env bash
case "\$1" in
    laptop)           exit $1 ;;
    external-monitor) exit $2 ;;
    lid-closed)       exit 1 ;;
    clamshell)        exit 1 ;;
    *)                exit 1 ;;
esac
STUB
    chmod +x "$fake/bin/panama-hw"
}

# systemd-inhibit records how it was called instead of holding anything.
cat >"$fake/systemd-inhibit" <<STUB
#!/usr/bin/env bash
printf '%s\n' "\$*" >>"$calls"
STUB
chmod +x "$fake/systemd-inhibit"

guard() {
    : >"$calls"
    PATH="$fake:$PATH" PANAMA_PATH="$fake" "$helper" guard >/dev/null 2>&1
}

# ── 2. Machines that should hold nothing ─────────────────────────────────────

stub_hw 1 0   # a desktop: not a laptop, external monitor present
guard || note 'the guard failed on a desktop instead of exiting cleanly'
[[ -s "$calls" ]] && note 'a desktop held a lid inhibitor, which it has no lid to inhibit'

stub_hw 0 1   # a laptop with no external display: must suspend normally
guard || note 'the guard failed on an undocked laptop instead of exiting cleanly'
[[ -s "$calls" ]] \
    && note 'an undocked laptop held a lid inhibitor, so closing it in a bag would not suspend'

# ── 3. A docked laptop holds the right one ───────────────────────────────────

stub_hw 0 0   # a laptop with an external display
guard
[[ -s "$calls" ]] || note 'a docked laptop held no inhibitor, so closing the lid would suspend mid-work'
recorded="$(cat "$calls" 2>/dev/null)"
grep -q -- '--what=handle-lid-switch' <<<"$recorded" \
    || note 'the inhibitor is not a handle-lid-switch inhibitor, so logind would still act on the lid'
grep -q -- '--mode=block' <<<"$recorded" \
    || note 'the inhibitor is a delay rather than a block, so logind would suspend anyway after its timeout'
grep -q -- '--who=panama-lid' <<<"$recorded" \
    || note 'the inhibitor does not identify itself, so systemd-inhibit --list cannot explain who is holding it'
grep -q -- '--why=' <<<"$recorded" \
    || note 'the inhibitor states no reason'

# ── 4. Locking on the way down stays hypridle's job ──────────────────────────

grep -q 'before_sleep_cmd' "$hypridle" \
    || note 'the shipped hypridle config no longer locks before sleep, which is what makes a lid-close suspend a locked one'
uncommented "$helper" | grep -q 'loginctl lock-session\|hyprlock' \
    && note 'the lid helper locks the session itself, duplicating what hypridle already does on every sleep'

# ── 5. Opening the lid restores the whole configured record ──────────────────
#
# Everything below runs against a stubbed `hyprctl`, so nothing here reaches the
# compositor: the stub answers the monitor query from a fixture and writes the
# rule it was asked to apply into a file. `eval` is what the helper uses (a
# runtime rule, gone at the next reload) rather than `keyword`, which would
# persist -- so even a real run of this would be recoverable; it still does not
# happen.

if command -v jq >/dev/null 2>&1; then
    emitted="$work/emitted"
    config_home="$work/config"
    mkdir -p "$config_home/panama"

    cat >"$fake/hyprctl" <<STUB
#!/usr/bin/env bash
# The monitor query: one internal panel and one external display.
if [[ "\$1" == "-j" ]]; then
    printf '%s\n' '[{"name":"eDP-1"},{"name":"DP-2"}]'
    exit 0
fi
printf '%s\n' "\$*" >>"$emitted"
STUB
    chmod +x "$fake/hyprctl"

    # `open` with whatever this fixture stores for the internal panel.
    open_with() {
        : >"$emitted"
        printf '%s' "$1" >"$config_home/panama/settings.json"
        PATH="$fake:$PATH" PANAMA_PATH="$fake" XDG_CONFIG_HOME="$config_home" \
            "$helper" open >/dev/null 2>&1
        cat "$emitted" 2>/dev/null
    }

    carries() {
        grep -Fq "$2" <<<"$1" \
            || note "opening the lid emitted no $3 (rule was: $(tr -d '\n' <<<"$1"))"
    }

    # A fully described panel. Every one of these fields is something the
    # Displays page can write and the old four-key rule threw away.
    full='{"displays":{"eDP-1":{"mode":"2880x1800@120","scale":2,"transform":1,
        "x":1920,"y":0,"primary":false,"vrrMode":1,"colorProfile":"wide",
        "bitdepth":10,"sdrBrightness":1.2,"sdrSaturation":0.9}}}'
    rule="$(open_with "$full")"

    [[ -n "$rule" ]] || note 'opening the lid on a laptop emitted no monitor rule at all'
    carries "$rule" 'hl.monitor'          'monitor rule'
    carries "$rule" 'eDP-1'               'output name'
    carries "$rule" '2880x1800@120'       'stored mode'
    # Position comes from the stored coordinates. "auto" here would move the
    # panel out from under the arrangement the user dragged.
    carries "$rule" '1920x0'              'position from the stored x and y'
    carries "$rule" 'scale = 2'           'stored scale'
    carries "$rule" 'transform = 1'       'stored rotation'
    carries "$rule" 'vrr = 1'             'stored variable refresh rate'
    carries "$rule" 'bitdepth = 10'       'stored bit depth'
    carries "$rule" 'cm = "wide"'         'stored colour profile'
    carries "$rule" 'sdrbrightness = 1.2' 'stored SDR brightness'
    carries "$rule" 'sdrsaturation = 0.9' 'stored SDR saturation'

    # jq prints an absent key as the string "null", which reaches a rule as a
    # value the compositor will reject or, worse, accept.
    grep -q 'null' <<<"$rule" \
        && note 'the emitted rule contains a null, so an unset field was written out rather than left off'

    # ── Invalid values drop one at a time, and geometry survives ─────────────
    #
    # The two failure directions monitors.lua chose, and the reason they
    # differ: an unreadable colour costs a shade, so it drops on its own and
    # the arrangement stands. Geometry is the opposite -- guessing half of it
    # can strand an output where no cursor reaches -- so a bad one refuses the
    # whole record and the panel comes back on its preferred mode.
    broken='{"displays":{"eDP-1":{"mode":"2880x1800@120","scale":2,"transform":1,
        "x":1920,"y":0,"primary":false,"vrrMode":7,"colorProfile":"chartreuse",
        "bitdepth":12,"sdrBrightness":9,"sdrSaturation":"a lot"}}}'
    rule="$(open_with "$broken")"

    carries "$rule" '2880x1800@120' 'mode, which is valid and must survive a bad colour profile'
    carries "$rule" '1920x0'        'position, which is valid and must survive a bad colour profile'
    carries "$rule" 'scale = 2'     'scale, which is valid and must survive a bad colour profile'
    carries "$rule" 'transform = 1' 'rotation, which is valid and must survive a bad colour profile'
    for bad in 'vrr = 7' 'chartreuse' 'bitdepth = 12' 'sdrbrightness = 9' 'a lot'; do
        grep -Fq "$bad" <<<"$rule" \
            && note "an out-of-range value reached the compositor: $bad"
    done

    # Bad geometry takes the record down with it, back to the panel's own
    # preferred mode -- never a partially honoured rule.
    for field in '"transform":9' '"scale":7' '"mode":"enormous"'; do
        rule="$(open_with "{\"displays\":{\"eDP-1\":{\"mode\":\"2880x1800@120\",
            \"scale\":2,\"transform\":1,${field}}}}")"
        carries "$rule" 'mode = "preferred"' "a fallback to the preferred mode for a record with $field"
        grep -Fq '2880x1800@120' <<<"$rule" \
            && note "a record with $field was half-honoured: its mode was applied anyway"
    done

    # ── No stored position means automatic placement ─────────────────────────
    legacy='{"displays":{"eDP-1":{"mode":"2880x1800@120","scale":2,"transform":0}}}'
    rule="$(open_with "$legacy")"
    carries "$rule" 'position = "auto"' 'automatic position for a record with no stored coordinates'
    carries "$rule" '2880x1800@120'     'mode from a record predating the layout fields'
    grep -Fq 'x0' <<<"$rule" \
        && note 'a record with no stored coordinates produced a position anyway'

    # A half-written position is refused the way monitors.lua refuses it:
    # guessing the other half can strand an output where nothing can reach it.
    half='{"displays":{"eDP-1":{"mode":"2880x1800@120","scale":2,"transform":0,"x":1920}}}'
    rule="$(open_with "$half")"
    carries "$rule" 'position = "auto"' 'automatic position for a half-written record'

    # ── Nothing stored at all falls back to the panel's own preference ───────
    rule="$(open_with '{}')"
    carries "$rule" 'mode = "preferred"' 'preferred mode when nothing is stored'
    carries "$rule" 'position = "auto"'  'automatic position when nothing is stored'
    carries "$rule" 'scale = "auto"'     'automatic scale when nothing is stored'

    # ── It stays a runtime rule ──────────────────────────────────────────────
    # `hyprctl keyword` would write the approximation into the compositor's
    # live configuration, where a reload would not undo it.
    uncommented "$helper" | grep -q 'hyprctl keyword' \
        && note 'the lid helper applies monitor rules with keyword rather than eval, so a wrong rule would outlive a reload'
fi

# ── The service that drives it ───────────────────────────────────────────────

[[ -r "$service" ]] || note 'LidPolicy.qml is missing, so nothing notices a display being connected'
grep -q 'eDP|LVDS|DSI' "$service" \
    || note 'the service does not distinguish the built-in panel from an external display'
grep -q 'Connections { target: LidPolicy }' "$shell_qml" \
    || note 'nothing keeps LidPolicy alive, so it would only start when some page happened to reference it'

# Status is machine-readable, for the Power page and panama-doctor.
stub_hw 0 0
status="$(PATH="$fake:$PATH" PANAMA_PATH="$fake" "$helper" status 2>/dev/null)"
if command -v jq >/dev/null 2>&1; then
    jq -e . >/dev/null 2>&1 <<<"$status" || note 'status does not emit valid JSON'
    for key in laptop lidClosed externalMonitor clamshell inhibited; do
        jq -e "has(\"$key\")" >/dev/null 2>&1 <<<"$status" || note "status omits $key"
    done
fi

if (( ${#findings[@]} > 0 )); then
    printf 'lid contract: %d finding(s)\n' "${#findings[@]}" >&2
    printf '  - %s\n' "${findings[@]}" >&2
    exit 1
fi

printf 'lid contract: PASS\n'