#!/bin/sh

# Base variables
root="${HOME}/myip"
file="${root}/$(hostname -f).txt"

# Ensure root dir
mkdir -p "${root}"

# Ensure git repo
cd "${root}"
[[ -d "${root}/.git" ]] || {
  git init
  git remote add origin git@github.com:tzvetkoff/myip.git
}

# Fetch and reset to latest master
git fetch origin master
git reset --hard origin/master

# Get date
date=$(date '+%c')
# Get public ip address
new_ip=$(dig +short TXT o-o.myaddr.l.google.com @ns1.google.com | sed s/'"'//g)

# Some error checking
[[ -z "${new_ip}" ]] && exit 1

# Parse old public ip address and check for changes
if [[ -f "${file}" ]]; then
  old_ip=$(cat "${file}" | awk 'FNR == 2 { print }')

  if [[ "${new_ip}" == "${old_ip}" ]]; then
    exit 255
  fi
fi

# Create new file
> "${file}"
echo "${date}" >> "${file}"
echo "${new_ip}" >> "${file}"

# Add, commit, push
git add .
git commit -m 'Update'
git push origin master