#!/bin/bash
# I, Ian Kelling, follow the GNU license recommendations at
# https://www.gnu.org/licenses/license-recommendations.en.html. They
# recommend that small programs, < 300 lines, be licensed under the
# Apache License 2.0. This file contains or is part of one or more small
# programs. If a small program grows beyond 300 lines, I plan to change
# to a recommended GPL license.

# Copyright 2024 Ian Kelling

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# ffs = ffmpeg stream

# todo: figure out how to record mumble
# todo: get icecast on li.b8.nz
# todo: https://superuser.com/questions/1106674/how-to-add-blank-lines-above-the-bottom-in-terminal

if ! test "$BASH_VERSION"; then echo "error: shell is not bash" >&2; exit 1; fi
shopt -s inherit_errexit 2>/dev/null ||: # ignore fail in bash < 4.4
set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" exit status: $?, PIPESTATUS: ${PIPESTATUS[*]}" >&2' ERR


# 3 mountpoints: fsf-sysops (public), fsf (default, all staff), fsf-tech (tech team)
case $1 in
  sysops|tech)
    mount_suffix=-$1
    ;;
esac

host=live.iankelling.org:8000
if [[ $(dig +short @10.2.0.1 -x 10.2.0.2 2>&1 ||:) == kd.b8.nz. ]] \
     && ip n show 10.2.0.1 | grep . &>/dev/null; then
  host=127.0.0.1:8000
fi

pass=$(sed -n 's/ *<source-password>\([^<]*\).*/\1/p' /p/c/icecast.xml)


tmpf=$(mktemp)
xrandr >$tmpf

# example xrandr output: 1280x800+0+0
primary_res=$(awk '$2 == "connected" && $3 == "primary" { print $4 }' $tmpf | sed 's/+.*//')
secondary_res=$(awk '$2 == "connected" && $3 != "primary" { print $3 }' $tmpf | sed 's/+.*//')

if [[ $secondary_res ]]; then
  # assumes secondary is on the right
  x_offset=${primary_res%%x*}
  secondary_x=${secondary_res%%x*}
  secondary_y=${secondary_res##*x}
  stream_res=$(( secondary_x / 2 ))x$(( secondary_y / 2))
else
  x_offset=0
  stream_res=$primary_res
fi


opts=(
  # nice to have: be a little less verbose
  -hide_banner
  -video_size $stream_res
  -f x11grab
  -framerate 4
  # input options come before -i
  -i :0.0+$x_offset.0
  -vf drawbox=color=black
  -vcodec libvpx
  -g 8
  -quality realtime
  -threads 2
  -error-resilient 1
  -content_type video/webm
  -f webm
  icecast://source:$pass@$host/fsf$mount_suffix.webm

)


rm -f /tmp/iank-ffmpeg
mkfifo -m 0600 /tmp/iank-ffmpeg
echo executing: ffmpeg -stdin ${opts[@]}
# ffmpeg sits and waits until we do this. dunno why. whatever.
echo >/tmp/iank-ffmpeg &
ffmpeg ${opts[@]} </tmp/iank-ffmpeg