#!/bin/bash
# WL_PRESENT_DMENU="tofi"
usage() {
  echo "usage: wl-present [options] <command> [argument]"
  echo
  echo "start wl-mirror and control the mirrored output and region in a convenient way"
  echo
  echo "commands:"
  echo "  help                        show this help"
  echo "  mirror [output] [options]   start wl-mirror on output [output] (default asks via slurp)"
  echo "  set-output [output]         set the recorded output (default asks via slurp)"
  echo "  set-region [region]         set the recorded region (default asks via slurp)"
  echo "  unset-region                unset the recorded region"
  echo "  set-scaling [scale]         set the scaling mode (default asks via rofi)"
  echo "  freeze                      freeze the screen"
  echo "  unfreeze                    resume the screen capture after freeze"
  echo "  toggle-freeze               toggle freeze state of screen capture"
  echo "  fullscreen                  fullscreen the wl-mirror window"
  echo "  unfullscreen                unfullscreen the wl-mirror window"
  echo "  fullscreen-output [output]  set fullscreen target output, implies fullscreen (default asks via slurp)"
  echo "  no-fullscreen-output        unset fullscreen target output, implies unfullscreen"
  echo "  custom [options]            send custom options to wl-mirror (default asks via rofi)"
  echo
  echo "options:"
  echo "  -n, --name                  use an alternative pipe name (default is wl-present)"
  echo "                              this allows multiple instances of wl-present to run"
  echo "                              at the same time."
  echo "dependencies:"
  echo "  wl-mirror, bash, slurp, pipectl (optional), and either wofi, wmenu, rofi, fuzzel, or dmenu"
  echo
  echo "environment variables":
  echo "  WL_PRESENT_DMENU            overrides the used dmenu implementation"
  echo "  WL_PRESENT_PIPECTL          overrides the used pipectl implementation"
  echo "  WL_PRESENT_SLURP            overrides the used slurp implementation"
  echo "  WL_PRESENT_PIPE_NAME        overrides the default pipe name (default is wl-present)"
  exit 0
}

if [[ -n "$WL_PRESENT_DMENU" ]]; then
  DMENU="$WL_PRESENT_DMENU"
elif type -p wofi >/dev/null; then
  DMENU="wofi -d"
elif type -p wmenu >/dev/null; then
  DMENU=wmenu
elif type -p fuzzel >/dev/null; then
  DMENU="fuzzel -d"
elif type -p rofi >/dev/null; then
  DMENU="rofi -dmenu"
else
  DMENU=dmenu
fi

if [[ -n "$WL_PRESENT_PIPECTL" ]]; then
  PIPECTL="$WL_PRESENT_PIPECTL"
elif type -p pipectl >/dev/null; then
  PIPECTL=pipectl
else
  PIPECTL=pipectl-shim
fi

if [[ -n "$WL_PRESENT_SLURP" ]]; then
  SLURP="$WL_PRESENT_SLURP"
else
  SLURP=slurp
fi

if [[ -n "$WL_PRESENT_PIPE_NAME" ]]; then
  PRESENT_PIPE_NAME="$WL_PRESENT_PIPE_NAME"
else
  PRESENT_PIPE_NAME=wl-present
fi

pipectl-shim() {
  PIPEPATH="${XDG_RUNTIME_DIR:-"${TMPDIR:-/tmp}"}"
  PIPENAME="pipectl.$(id -u).pipe"
  MODE=
  FORCE=0

  while [[ $# -gt 0 && "${1:0:1}" == "-" ]]; do
    opt="$1"
    shift
    case "$opt" in
    -n | --name)
      arg="$1"
      shift
      PIPENAME="pipectl.$(id -u).$arg.pipe"
      ;;
    -i | --in) MODE=in ;;
    -o | --out) MODE=out ;;
    -f | --force) FORCE=1 ;;
    --) break ;;
    esac
  done

  PIPE="$PIPEPATH/$PIPENAME"

  case "$MODE" in
  "in") if [[ ! -p "$PIPE" ]]; then
    echo "error: could not open pipe at '$PIPE': No such file or directory" >&2
    return 1
  else
    cat >"$PIPE"
  fi ;;
  "out") if [[ "$FORCE" -eq 0 && -p "$PIPE" ]]; then
    echo "error: cannot create pipe at '$PIPE': File exists" >&2
    return 1
  else
    [[ "$FORCE" -eq 1 ]] && rm -f "$PIPE"
    mkfifo "$PIPE"
    (
      tail -f "$PIPE" &
      echo >"$PIPE"
      wait
    )
    rm -f "$PIPE"
  fi ;;
  esac
}

slurp-output() {
  $SLURP -or -f '%o' 2>/dev/null
}

slurp-region() {
  $SLURP 2>/dev/null
}

slurp-output-or-region() {
  $SLURP -o -f '%o|%x,%y %wx%h' 2>/dev/null
}

mirror() {
  if [[ "$#" -eq 0 || "$1" =~ ^- ]]; then
    OUTPUT_REGION=$(ask-output-or-region)
    IFS='|' read -r OUTPUT REGION <<<"$OUTPUT_REGION"

    mirror "$OUTPUT" -r "$REGION" "$@"
    return
  fi

  OUTPUT="$1"
  shift

  $PIPECTL -n "$PRESENT_PIPE_NAME" -o | wl-mirror -S "$@" "$OUTPUT"
}

mirror-cmd() {
  $PIPECTL -n "$PRESENT_PIPE_NAME" -i <<<"$1"
}

set-output() {
  mirror-cmd "$1"
}

set-region() {
  mirror-cmd "-r '$1'"
}

set-scaling() {
  mirror-cmd "-s $1"
}

set-fullscreen-output() {
  mirror-cmd "--fullscreen-output $1"
}

ask-output() {
  slurp-output
  [[ $? -ne 0 ]] && exit 1
}

ask-region() {
  slurp-region
  [[ $? -ne 0 ]] && exit 1
}

ask-output-or-region() {
  slurp-output-or-region
  [[ $? -ne 0 ]] && exit 1
}

ask-scaling() {
  (
    echo fit
    echo cover
    echo exact
    echo linear
    echo nearest
  ) | $DMENU -p "wl-present scaling"
  [[ $? -ne 0 ]] && exit 1
}

ask-custom() {
  cat <<EOF | $DMENU -p "wl-present custom"
--verbose
--no-verbose
--show-cursor
--no-show-cursor
--invert-colors
--no-invert-colors
--freeze
--unfreeze
--toggle-freeze
--fullscreen
--no-fullscreen
--fullscreen-output
--no-fullscreen-output
--scaling fit
--scaling cover
--scaling exact
--scaling linear
--scaling nearest
--backend
--transform
--region
--no-region
EOF
  [[ $? -ne 0 ]] && exit 1
}

while [[ $# -gt 0 && "${1:0:1}" == "-" ]]; do
  opt="$1"
  shift
  case "$opt" in
  -n | --name)
    arg="$1"
    shift
    PRESENT_PIPE_NAME="$arg"
    ;;
  -h | --help) usage ;;
  --) break ;;
  esac
done

if [[ $# -eq 0 ]]; then
  usage
fi

case "$1" in
help) usage ;;
mirror)
  shift
  mirror "$@"
  ;;
set-output) set-output "${2:-$(ask-output)}" ;;
set-region) set-region "${2:-$(ask-region)}" ;;
unset-region | no-region) mirror-cmd --no-region ;;
set-scaling) set-scaling "${2:-$(ask-scaling)}" ;;
freeze) mirror-cmd --freeze ;;
unfreeze) mirror-cmd --unfreeze ;;
toggle-freeze) mirror-cmd --toggle-freeze ;;
fullscreen) mirror-cmd --fullscreen ;;
unfullscreen | no-fullscreen) mirror-cmd --no-fullscreen ;;
fullscreen-output) set-fullscreen-output "${2:-$(ask-output)}" ;;
no-fullscreen-output) mirror-cmd --no-fullscreen-output ;;
custom) mirror-cmd "${2:-$(ask-custom)}" ;;
*) usage ;;
esac