#!/bin/sh
MESSAGE=$1
BASE_DIR=$2
PR_DIR=$3
shift 3

# this assumes we're running from the repository root
AVR_SIZE=$(echo .dependencies/avr-gcc-*/bin/avr-size)
test -x "$AVR_SIZE" || exit 2

avr_size()
{
    "$AVR_SIZE" --mcu=atmega2560 -C "$@"
}

avr_flash()
{
    avr_size "$@" | sed -ne 's/^Program: *\([0-9]\+\).*/\1/p'
}

avr_ram()
{
    avr_size "$@" | sed -ne 's/^Data: *\([0-9]\+\).*/\1/p'
}

cat <<EOF > "$MESSAGE"
| ΔFlash (bytes) | ΔSRAM (bytes) |
| -------------- | ------------- |
EOF

base_bin=$(echo ${BASE_DIR}/firmware)
base_flash=$(avr_flash "$base_bin")
base_ram=$(avr_ram "$base_bin")

pr_bin=$(echo ${PR_DIR}/firmware)
pr_flash=$(avr_flash "$pr_bin")
pr_ram=$(avr_ram "$pr_bin")

flash_d=$(($pr_flash - $base_flash))
ram_d=$(($pr_ram - $base_ram))

echo "| $flash_d | $ram_d |" >> "$MESSAGE"