#!/bin/bash

############################
# Variables                #
############################

# User's ID
USRID=`id -un`

# Source Shamu server for copy
SOURCE_SVR=login.shamu.utsa.edu

# Destination Arc server for copy
DEST_SVR=arc.utsa.edu


############################
# Functions                #
############################

display_usage_and_exit () {
   echo -e "\nUsage: $ migrate-shamu2arc [help] home|work|both\n"
   exit
}

display_help () {
  echo -e "\nThis script is meant to help users move their data from the Shamu HPC environment"
  echo -e "to the Arc HPC environment using rsync.  The script will move either the user's "
  echo -e "home, work or both directories from Shamu to Arc.  It accepts one argument "
  echo -e "indicating which option to use."
  echo
  echo -e "If subdirectories or paths other than /home/abc123 or /work/abc123 need to be copied"
  echo -e "or other rsync options are needed, use the rsync linux utility directly."
  echo -e "See https://hpcsupport.utsa.edu/foswiki/bin/view/ARC/MigratingDataToArc"
  echo -e "for more information."

  display_usage_and_exit
}

get_final_approval () {
  echo -e "\nRsync will copy..."
  if [ $1 = "home-new" -o $1 = "work" ]
  then
    echo -e "From: ${USRID}@${SOURCE_SVR}:/$1/${USRID}"
    echo -e "To:   ${USRID}@${DEST_SVR}:/$1/${USRID}\n"
    echo -e "Note that you will be prompted for your Shamu credentials to start the copy.\n"
  else
    echo -e "From: ${USRID}@${SOURCE_SVR}:/home-new/${USRID}"
    echo -e "To:   ${USRID}@${DEST_SVR}:/home-new/${USRID}"
    echo -e "      And"
    echo -e "From: ${USRID}@${SOURCE_SVR}:/work/${USRID}"
    echo -e "To:   ${USRID}@${DEST_SVR}:/work/${USRID}\n"
    echo -e "Note that you will be prompted for your Shamu credentials twice for the copies."
    echo -e "Once for the \"home\" directory and the other for the \"work\" directory.\n"
  fi

  echo -e "Also, note that any files from Shamu that already exist on Arc will not be copied over.\n"

  read -n 1 -r -p "Enter Y|y to proceed, any other key to cancel:"
  echo

  if [[ ! $REPLY =~ ^[Yy]$ ]]
  then
    echo -e "\nCancelled per user request."
    exit 1
  fi
}

do_rsync () {
  get_final_approval $1

  if [ $1 = "home-new" ]
  then
    rsync -avtr --ignore-existing -e 'ssh -p 1209' ${USRID}@${SOURCE_SVR}:/$1/${USRID}/ /home/${USRID}/testrsync
  elif [ $1 = "work" ]
  then
    rsync -avtr --ignore-existing -e 'ssh -p 1209' ${SOURCE_PORT_OPTION} ${USRID}@${SOURCE_SVR}:/$1/${USRID}/ /$1/${USRID}
  else
    rsync -avtr --ignore-existing -e 'ssh -p 1209' ${SOURCE_PORT_OPTION} ${USRID}@${SOURCE_SVR}:/home-new/${USRID}/ /home/${USRID}
    rsync -avtr --ignore-existing -e 'ssh -p 1209' ${SOURCE_PORT_OPTION} ${USRID}@${SOURCE_SVR}:/work/${USRID}/ /work/${USRID}
  fi
}

############################
# MAIN                     #
############################

# Validate argument - there should only be one
[ $# -lt 1 -o $# -gt 2 ] && display_usage_and_exit

# Verify script is being run on Arc
RUNLOCATION=`sacctmgr -n show cluster format=cluster`
if [[ ! $RUNLOCATION =~ "arc_clust+" ]]
then
  echo -e "\nThis script is ony meant to be run on nodes in the Arc cluster.\n"
  exit 1
fi

# Process through the arguments
for arg in "$@"
do
   case $arg in
      help)
         display_help
         ;;
      home)
         # Setup to rsync home directory
         do_rsync home-new
         ;;
      work)
         # Setup to copy work directory
         do_rsync work
         ;;
      both)
         # Copy both home & work directory
         do_rsync both
         ;;
      *)
         echo -e "\nError: Received an invalid argument\n"
         display_help
         echo -e "\nExiting."
   esac
done