1 files changed, 126 insertions, 0 deletions
diff --git a/lights-out.in b/lights-out.in
new file mode 100644
index 0000000..144d7bd
--- /dev/null
+++ b/lights-out.in
@@ -0,0 +1,126 @@
+#!/bin/bash
+
+display_help() {
+  >&2 printf 'lights-out version #VERSION#\n'
+  >&2 printf '\n'
+  >&2 printf 'usage:\n'
+  >&2 printf '  lights-out get $input: display inverted pin state of $input\n'
+  >&2 printf '  lights-out help: display this help and exit\n'
+  >&2 printf '  lights-out init: init gpio\n'
+  >&2 printf '  lights-out name: print the name of the server\n'
+  >&2 printf '  lights-out push $output $time: simulate push on $output for $time seconds\n'
+  >&2 printf '  lights-out turn on: turn on machine if not yet running\n'
+}
+
+check_argument_count() {
+  local count="$1"
+  shift
+  if [ $# -ne "${count}" ]; then
+    >&2 printf 'wrong number of arguments: "%s" expects %s argument' "$1" "${count}"
+    if [ "${count}" -ne 1 ]; then
+      printf 's'
+    fi
+    printf ', but %s were given\n\n' "$#"
+    display_help
+    exit 1
+  fi
+}
+
+if [ $# -lt 1 ]; then
+  display_help
+  exit 1
+fi
+
+if [ ! -r '#ETCDIR#/lights-out.conf' ]; then
+  >&2 printf 'cannot read config file "#ETCDIR#/lights-out.conf"\n'
+  exit 1
+fi
+
+if ! command -v gpio >/dev/null 2>&1; then
+  >&2 printf 'cannot find command "gpio" - is it installed?\n'
+  exit
+fi
+
+unset inputs
+unset outputs
+declare -A inputs
+declare -A outputs
+
+. '#ETCDIR#/lights-out.conf'
+
+if [ -z "${inputs['power']}" ]; then
+  >&2 printf 'invalid config "#ETCDIR#/lights-out.conf": no power input defined.\n'
+  exit 1
+fi
+
+if [ -z "${outputs['power']}" ]; then
+  >&2 printf 'invalid config "#ETCDIR#/lights-out.conf": no power output defined.\n'
+  exit 1
+fi
+
+if [ -z "${server}" ]; then
+  >&2 printf 'invalid config "#ETCDIR#/lights-out.conf": no server name defined.\n'
+  exit 1
+fi
+
+case "$1" in
+  'get')
+    check_argument_count 2 "$@"
+    if [ -z "${inputs["$2"]}" ]; then
+      >&2 printf 'unknown input "%s"\n\n' "$2"
+      display_help
+      exit 1
+    fi
+    value=$(
+      gpio read "${inputs["$2"]}"
+    ) || exit $?
+    echo $((1-value))
+  ;;
+  'help')
+    display_help
+  ;;
+  'init')
+    check_argument_count 1 "$@"
+    for input in "${inputs[@]}"; do
+      gpio mode "${input}" in || exit $?
+      gpio mode "${input}" up || exit $?
+    done
+    for output in "${outputs[@]}"; do
+      gpio write "${output}" 0 || exit $?
+      gpio mode "${output}" out || exit $?
+    done
+  ;;
+  'name')
+    printf '%s\n' "${server}"
+  ;;
+  'push')
+    check_argument_count 3 "$@"
+    if [ -z "${outputs["$2"]}" ]; then
+      >&2 printf 'unknown output "%s"\n\n' "$2"
+      display_help
+      exit 1
+    fi
+    gpio write "${outputs["$2"]}" 1 || exit $?
+    sleep "$3"
+    gpio write "${outputs["$2"]}" 0 || exit $?
+  ;;
+  'turn')
+    if [ $# -ne 3 ] \
+    || [ "x$3" != 'xon' ]; then
+      >&2 printf 'unknown command "%s"\n\n' "$*"
+      display_help
+      exit 1
+    fi
+    value=$(
+      "$0" get power
+    ) || exit $?
+    if [ "${value}" -eq 0 ]; then
+      "$0" push power 0.1 || exit $?
+    fi
+  ;;
+  *)
+    >&2 printf 'unknown command "%s"\n\n' "$1"
+    display_help
+    exit 1
+  ;;
+esac