#!/usr/bin/env bash

#*******************************************************************************
#
# Bare Conductive Pi Cap Audio Mapper
# -----------------------------------
#
# map-audio-to-picap - outputs audio via the Pi Cap audio socket
#
# Written by Stefan Dzisiewski-Smith.
#
# This work is licensed under a Creative Commons Attribution-ShareAlike 3.0
# Unported License (CC BY-SA 3.0) http://creativecommons.org/licenses/by-sa/3.0/
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
#
#*******************************************************************************

# halt on any error
set -e

CONFIG_DTOVERLAY_COMMENT="# remap audio to Pi Cap socket"
CONFIG_DTOVERLAY_LINE="dtoverlay=pwm-2chan,pin=12,pin2=13,func=4,func2=4"
CONFIG_FILE_PATH="/boot/config.txt"

THIS_SCRIPT_NAME=$(basename "$0")

if [ "$EUID" -ne 0 ]; then
	echo -e "This utility needs to be run as root to work. Try running: \n  sudo $THIS_SCRIPT_NAME"
 	exit 1
fi

# if the config line already exists (but prepended with "#") in /boot/config.txt, remove the "#"
sudo sed -i -e "s/#$CONFIG_DTOVERLAY_LINE/$CONFIG_DTOVERLAY_LINE/g" "$CONFIG_FILE_PATH"

# if we still can't find the config line (probably because we didn't find it first time around) append two newlines, a comment, the config lines and another newline (phew!)
sudo sed -i -e "\|$CONFIG_DTOVERLAY_LINE|h; \${x;s|$CONFIG_DTOVERLAY_LINE||;{g;t};a\\" -i -e "\n\n$CONFIG_DTOVERLAY_COMMENT\n$CONFIG_DTOVERLAY_LINE" -i -e "}" "$CONFIG_FILE_PATH"

if [ -z "$DONT_REBOOT" ]; then
	read -r -p $'PCM audio has been mapped to the Pi Cap headphone socket. \nFor this change to take effect, we need to reboot.\n\nDo you want to do this now? [y/n]\n'
	case $REPLY in
	    [yY][eE][sS]|[yY]) 
	        sync ; sudo reboot now
	        ;;
	    *)
	        ;;
	esac
fi

exit 0
