#!/bin/bash

############ funcs

function __dru_rm_from_both_core_dirs {
  echo 
  rm -dr drupal-$site_drv/$1 drupal-$latest_drv/$1 && echo "OK: Done a : rm -dr drupal-$site_drv/$1 drupal-$latest_drv/$1"

}

function __dru_cp_from_site_dir_to_both_core_dirs {
echo
  for dest in drupal-$site_drv drupal-$latest_drv
  do
    for src in "$@"
    do

if [[ -e "$site_dir/$src" ]] # -e checks for both files and dirs
then cp -pr "$site_dir/$src" "$dest/" && echo "OK: Done a: cp -pr '$site_dir/$src' '$dest/'"
fi

    done
  done
echo "
OK: So, now the current core is ready for diffing and the latest core is almost ready to go live."
}

############# Requirements

# This script requires that you have drush/link to drush in your $PATH
if [[ -z `which drush` ]]
then echo "drush not found in PATH! Exiting..."; exit 2
fi




########### determine versions


# Drupal version from CHANGELOG.txt of the site we update
if [[ -f CHANGELOG.txt ]]
then site_drv=`cat CHANGELOG.txt  | grep "^Drupal" | sed 's/\,.*$//' | sed 's/Drupal\ //' | head -1`
fi

site_dir=`pwd`

if [[ -z $site_drv ]] # can be empty (-z) either because CHANGELOG.txt missing or corrupt
then echo "Unable to get Drupal site version. Maybe you are not in its root dir?. Exiting..."; exit 1;
fi
echo "OK: Your site's current Drupal core version:       |$site_drv|. (determined via CHANGELOG.txt)"


latest_drv=`drush info drupal | grep "drupal" | head -1 | awk '{print $2}'`
echo "OK: The latest Drupal core version is:             |$latest_drv|. (determined via 'drush info drupal')"
#exit






############### download orig and new


drupal_updates_dir="/tmp/drupal_updates"
echo "OK: Removing $drupal_updates_dir  - to start fresh there."
rm -fdr $drupal_updates_dir && echo "OK: Removed. Creating it again and going there."
mkdir   $drupal_updates_dir
cd      $drupal_updates_dir

echo "
OK: All the time we are working from $drupal_updates_dir.
"

#pwd

# We have 3 dirs in this show - current site, drupal core with the same version and latest drupal core

echo "
OK: Your site is at                           : $site_dir
OK: Drupal core with the same version is at   : ./drupal-$site_drv
OK: Drupal core with the LATEST version is at : ./drupal-$latest_drv
OK: the working directory (a.k.a. '.') is     : `pwd`
"

#################### if proj=core auto-resolve the sites diff, as well as the backup and cache dirs


# remove /sites dir from both dirs
drush dl drupal-$latest_drv #|| echo "ERR 33"; exit
drush dl drupal-$site_drv   #|| echo "Error 34"; exit
__dru_rm_from_both_core_dirs    sites  && echo "OK: removed sites from untouched core versions cause we will put our live site's 'sites' dir there"
__dru_cp_from_site_dir_to_both_core_dirs   sites backup cache



################## now do an interactive diff reolution - some things deleted, others copied , others left alone = hacks left to reside in the new version
######## the last diff should be NULL = dirs match exactly


diff_command="diff -qr $site_dir drupal-$site_drv"
diff_output=`$diff_command`

echo "
diff command:
$diff_command

diff output:
$diff_output
"