#! /bin/bash
set -ex

# add stuff we want to config.txt
config="mnt/boot/config.txt"
add_file="$(mktemp)"
trap 'rm -f "$add_file"' EXIT

cat >"$add_file" <<'END'
dtparam=spi=on
# we can adjust these values as needed
dtparam=cooling_fan=on,fan_temp0=62000,fan_temp0_hyst=8000,fan_temp0_speed=80,fan_temp1=70000,fan_temp1_hyst=5000,fan_temp1_speed=100,fan_temp2=76000,fan_temp2_hyst=4000,fan_temp2_speed=170,fan_temp3=80000,fan_temp3_hyst=3000,fan_temp3_speed=250
# enable i2s for audio
dtparam=i2s=on
# use an external antenna instead of the pcb antenna on the CM
dtparam=ant2
# load our audio driver
dtoverlay=toesaudio
# enable gpio12 which we use to reset the audio codec
gpio=12=op,dh
# enable serial over usb in gadget/peripheral mode
dtoverlay=dwc2,dr_mode=peripheral
END

if ! sudo grep -qx 'dtparam=spi=on' "$config"; then
	echo "missing dtparam=spi=on in $config" >&2
	exit 1
fi

sudo awk -v add_file="$add_file" '
	$0 == "dtparam=spi=on" && !done {
		while ((getline line < add_file) > 0) {
			print line
		}
		close(add_file)
		done = 1
		next
	}
	{ print }
' "$config" | sudo tee "$config.tmp" >/dev/null
sudo mv "$config.tmp" "$config"

# we don't need fancy graphics. we don't have a screen.
printf '\ngpu_mem=16\n' | sudo tee -a "$config" >/dev/null