#!/usr/bin/env bash
# focus-send - Trivial Focus testing tool
# Copyright (C) 2018-2022  Keyboard.io, Inc.
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation, version 3.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with
# this program. If not, see <http://www.gnu.org/licenses/>.

set -e

OS=$(uname -s)

# igncr absorbs CR from Focus CRLF line endings
# -echo is needed because raw doesn't turn it off on Linux
STTY_ARGS="9600 raw igncr -echo"

case ${OS} in
    Linux)
        DEVICE="${DEVICE:-/dev/ttyACM0}"
        ;;
    Darwin)
        # bash on macOS has a bug that randomly drops serial input
        if [ -n "$BASH_VERSION" ] && [ -x /bin/dash ]; then
            # Prevent loop in case someone exported it
            export -n BASH_VERSION
            exec /bin/dash "$0" "$@"
        fi
        DEVICE="${DEVICE:-/dev/cu.usbmodemCkbio01E}"
        ;;
    *)
        echo "Error Unknown OS : ${OS}" >&2
        exit 1
        ;;
esac

# Redirect prior to running stty, because macOS sometimes resets termios
# state upon last close of a terminal device.
exec < "${DEVICE}"
# shellcheck disable=SC2086 # intentional word splitting
stty $STTY_ARGS

read_reply () {
    while read -r line; do
        if [ "${line}" = "." ]; then
            break
        fi
        echo "${line}"
    done
}

# Flush any invalid commands out of input buffer.
# This could happen after a failed upload.
echo ' ' > "${DEVICE}"
read_reply > /dev/null
echo "$@" >"${DEVICE}"
read_reply