kde-caffeine/contents/scripts/caffeine.sh

#!/usr/bin/env bash
#
# enne2-caffeine — backend del widget Caffeine per KDE Plasma 6
#
# Blocca lo spegnimento/blocco dello schermo e la sospensione automatica usando
# systemd-inhibit (logind). PowerDevil/PolicyAgent onora le inibizioni logind:
#   what=sleep -> InterruptSession (niente sospensione automatica)
#   what=idle  -> ChangeScreenSettings (niente dim/spegnimento schermo, niente blocco)
# L'inibizione vive in unità systemd utente, quindi sopravvive al riavvio di
# plasmashell e si rilascia da sola alla fine della sessione.
#
# Uso:
#   caffeine.sh status
#   caffeine.sh on <screen|sleep> [minuti]
#   caffeine.sh switch <screen|sleep>          # cambia modalità mantenendo il timer
#   caffeine.sh off [notify]
#   caffeine.sh toggle <screen|sleep> [minuti]
#   caffeine.sh ensure-units <cartella-con-i-.service>
#
# SPDX-License-Identifier: MIT

set -uo pipefail

UNIT_SCREEN="enne2-caffeine-screen.service"
UNIT_SLEEP="enne2-caffeine-sleep.service"
STATE_DIR="${XDG_STATE_HOME:-$HOME/.local/state}/enne2-caffeine"
DEADLINE_FILE="$STATE_DIR/deadline"
USER_UNIT_DIR="${XDG_CONFIG_HOME:-$HOME/.config}/systemd/user"

SYSTEMCTL="$(command -v systemctl 2>/dev/null || true)"

fail() {
    echo "error=$1"
    exit 1
}

# systemd utente disponibile e interrogabile?
systemd_ok() {
    [ -n "$SYSTEMCTL" ] || return 1
    case "$("$SYSTEMCTL" --user is-active "$UNIT_SCREEN" 2>/dev/null)" in
        active|inactive|failed|activating|deactivating|unknown) return 0 ;;
        *) return 1 ;;
    esac
}

unit_state() {
    "$SYSTEMCTL" --user is-active "$1" 2>/dev/null
}

active_unit() {
    if [ "$(unit_state "$UNIT_SCREEN")" = "active" ]; then
        printf '%s\n' "$UNIT_SCREEN"
    elif [ "$(unit_state "$UNIT_SLEEP")" = "active" ]; then
        printf '%s\n' "$UNIT_SLEEP"
    fi
}

only_digits() {
    case "${1:-}" in
        ''|*[!0-9]*) printf '0\n' ;;
        *) printf '%s\n' "$1" ;;
    esac
}

cmd_ensure_units() {
    local src="${1:-}"
    [ -n "$src" ] && [ -d "$src" ] || fail "unit-source-missing"
    systemd_ok || fail "systemd-user-unavailable"
    mkdir -p "$USER_UNIT_DIR" || fail "cannot-create-unit-dir"
    local changed=0 f target
    for f in "$src"/*.service; do
        [ -e "$f" ] || continue
        target="$USER_UNIT_DIR/$(basename "$f")"
        if ! cmp -s "$f" "$target"; then
            cp -f "$f" "$target" || fail "cannot-copy-unit"
            changed=1
        fi
    done
    if [ "$changed" = 1 ]; then
        "$SYSTEMCTL" --user daemon-reload >/dev/null 2>&1
    fi
    echo "ok=1"
}

cmd_status() {
    mkdir -p "$STATE_DIR" 2>/dev/null
    if ! systemd_ok; then
        echo "backend=unsupported"
        echo "state=off"
        echo "mode=none"
        return 0
    fi
    echo "backend=systemd"

    local unit
    unit="$(active_unit)"
    case "$unit" in
        "$UNIT_SCREEN") echo "state=on"; echo "mode=screen" ;;
        "$UNIT_SLEEP")  echo "state=on"; echo "mode=sleep" ;;
        *)              echo "state=off"; echo "mode=none" ;;
    esac

    if [ -n "$unit" ] && [ -f "$DEADLINE_FILE" ]; then
        local d
        d="$(only_digits "$(cat "$DEADLINE_FILE" 2>/dev/null)")"
        if [ "$d" -gt 0 ]; then
            echo "deadline=$d"
        else
            rm -f "$DEADLINE_FILE"
        fi
    fi
}

apply_mode() {
    systemd_ok || fail "systemd-user-unavailable"
    "$SYSTEMCTL" --user stop "$UNIT_SCREEN" "$UNIT_SLEEP" >/dev/null 2>&1
    if [ "${1:-screen}" = "sleep" ]; then
        "$SYSTEMCTL" --user start "$UNIT_SLEEP" >/dev/null 2>&1 || fail "start-failed"
    else
        "$SYSTEMCTL" --user start "$UNIT_SCREEN" >/dev/null 2>&1 || fail "start-failed"
    fi
}

cmd_on() {
    local mode="${1:-screen}"
    local minutes
    minutes="$(only_digits "${2:-0}")"
    mkdir -p "$STATE_DIR" 2>/dev/null
    apply_mode "$mode" || return 1
    if [ "$minutes" -gt 0 ]; then
        echo "$(( $(date +%s) + minutes * 60 ))" > "$DEADLINE_FILE"
    else
        rm -f "$DEADLINE_FILE"
    fi
    echo "ok=1"
    cmd_status
}

cmd_switch() {
    apply_mode "${1:-screen}" || return 1
    echo "ok=1"
    cmd_status
}

cmd_off() {
    local notify="${1:-}"
    if systemd_ok; then
        "$SYSTEMCTL" --user stop "$UNIT_SCREEN" "$UNIT_SLEEP" >/dev/null 2>&1
    fi
    rm -f "$DEADLINE_FILE"
    if [ "$notify" = "notify" ] && command -v notify-send >/dev/null 2>&1; then
        notify-send -a "Caffeine" -i preferences-system-power-management \
            "Caffeine disattivato" \
            "Il timer è scaduto: schermo e sospensione tornano alla gestione automatica." || true
    fi
    echo "ok=1"
}

cmd_toggle() {
    local mode="${1:-screen}"
    local minutes
    minutes="$(only_digits "${2:-0}")"
    if systemd_ok && [ -n "$(active_unit)" ]; then
        cmd_off
    else
        cmd_on "$mode" "$minutes"
    fi
}

case "${1:-status}" in
    status)       cmd_status ;;
    on|start)     cmd_on "${2:-screen}" "${3:-0}" ;;
    switch)       cmd_switch "${2:-screen}" ;;
    off|stop)     cmd_off "${2:-}" ;;
    toggle)       cmd_toggle "${2:-screen}" "${3:-0}" ;;
    ensure-units) cmd_ensure_units "${2:-}" ;;
    version)      echo "name=enne2-caffeine"; echo "version=1.0" ;;
    *)            fail "unknown-command" ;;
esac