#!/bin/bash

PLATFORMDIR=/home/drupal/core

usage() {
  cat <<EOT
Usage: `basename $0` servername oldplatform newplatform

Migrate drupal site servername from oldplatform to newplatform.

EXAMPLE

 `basename $0` www.mysite.com drupal-6.15 drupal-6.16

EOT
}

if [ $# -ne 3 ] ; then
  usage
  exit 1
fi

servername=$1
currentplatform=$2
newplatform=$3

platform_dir() {
  echo "$PLATFORMDIR/$1"
}

platform_exists() {
  platform=$1

  if [ -d "`platform_dir $platform`" ] ; then
    return 0
  else
    return 1
  fi
}

site_dir() {
  echo "`platform_dir $2`/sites/$1"
}

site_exists() {
  site=$1
  platform=$2

  if [ -z "$platform" ] || [ -z "$site" ] ; then
    echo "Argument error: site_exists '$platform' '$site'" >&2
    return 1
  fi

  dir=`site_dir $site $platform`

  if [ -d "$dir" ] && [ ! -L "$dir" ] ; then
    return 0
  else
    return 1
  fi
}

findlinks() {
  site=$1
  platform=$2

  find `platform_dir $platform`/sites -maxdepth 1 -lname "$site/" -or -lname "$site"
}

if ! platform_exists $currentplatform ; then
  echo "Platform '$currentplatform' does not exist"
  exit 1
fi
if ! platform_exists $newplatform ; then
  echo "Platform '$newplatform' does not exist"
  exit 1
fi
if [ "$currentplatform" == "$newplatform" ] ; then
  echo "$currentplatform and $newplatform are the same platform!"
  exit 1
fi

if ! site_exists $servername $currentplatform ; then
  echo "$site does not exist under $platform/sites, or is not a directory"
  exit 1
fi

# Check for any symlinks to the current dir
links=`findlinks $servername $currentplatform`



# Everything checked out, do the work

set -e

pushd `platform_dir $newplatform`/sites

# Create symlinks first
for link in $links ; do
  sudo cp -va $link .
done

# Move the directory, and symlink from the old location
sudo mv -v `site_dir $servername $currentplatform` . && ln -v -s `site_dir $servername $newplatform` `site_dir $servername $currentplatform`

pushd `site_dir $servername $newplatform` && drush updatedb

popd
popd