#!/bin/bash

################################################################################
# STATE_MACHINE.SH
# ----------------
# This script saves the last message for a certain key and compares the next
# message for the same key to not have any repeating notifications.
#
# Author: Robin Meier - robin@meier.si
################################################################################

script_dir=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )

set -o allexport
source ${script_dir}/../config/state_machine
set +o allexport

mkdir -p ${script_dir}/../storage/state_machine

# Get input from standard input or via first parameter
if [[ $# -eq 0 ]]; then
  echo "[ERROR] Not enough arguments!"
  exit 1
elif [[ $# -eq 1 ]]; then
  message=$(timeout 32 cat)
  key=$1
elif [[ $# -eq 2 ]]; then
  key=$1
  message=$2
else
  echo "[ERROR] Too many arguments!"
  exit 1
fi

# Check if key is empty
if [[ -z "${key}" ]]; then
  echo "[ERROR] key argument is missing!"
  exit 1
fi

key_file="${script_dir}/../storage/state_machine/${key}.txt"

if [[ -f $key_file && -z "${message}" ]]; then
  # Previous message present and empty message now
  OLD_message=$(cat $key_file)
  echo "✅ Resolved"
  echo "$OLD_message"
  rm $key_file
  exit 0
elif [[ -f $key_file ]]; then
  # Message and previous message present
  OLD_message=$(cat $key_file)
  # Compare contents
  if [[ "$OLD_message" == "$message" ]]; then
    # Check last notification
    if [ "$(( $(date +"%s") - $(stat -c "%Y" "$key_file") ))" -gt "$RENOTIFY_AGE_SEC" ]; then
      touch $key_file
      echo "‼️Renotify"
    else
      exit 0
    fi
  else
    echo "$message" > $key_file
    echo "⁉️Changed"
  fi
else
  if [[ -z "${message}" ]]; then
    # No message present
    exit 0
  fi

  # New message present, create key_file, continue to relaying
  echo "$message" > $key_file
  echo "❗New"
fi

# Relay message if made it until here (Quotes are important here, so lines dont get .join(' ')-ed)
echo "$message"

exit 0