#!/bin/bash

CORE="6.x"
BASE_URL="http://updates.drupal.org/release-history"
TARGET_BASE=/home/drupal/contrib
CORE_BASE=/home/drupal/core
UPDATE_XML_CONF=/etc/egscripts/update-xml.conf

# Mode of operation
LIST=0
READ=0
FIND=0
MISSING=0
CONTRIBLIST=0
DOWNLOAD=0
VERSIONLIST=0
AUTODOWNLOAD=0

usage() {
  cat <<EOT

Usage: `basename $0` [ OPTIONS ] module [ version ] | -r

Create a symlink to a Drupal module in the server wide module directory from
the current directory.

If no specific version is specified, the recommended version for this core
release will be symlinked.

OPTIONS

  -b dir  - Specify target base directory. (default: $TARGET_BASE)
  -c core - Specify the required core compatability. (default: $CORE)
  -d      - Download the specified module to the target base directory.
  -f      - Find links to a module, effectively listing all sites which use
            the named module.  If no version is specified, all versions are 
            listed.
  -h      - Show this help.
  -l      - List available versions for module in the target base directory.
  -L      - List available versions for module at drupal.org or the update
            source specified by -x or -X.
  -m      - Fix missing.  Looks for broken symlinks in the current directory
            and downloads the missing versions to the target directory.
  -r      - Read modules from stdin.  One module per line, with the version
            number as an optional second parameter on each line.  If -d was
            specified, the modules will be downloaded to the target base 
            directory.  Otherwise, they will be symlinked in the current
            directory.
  -v      - List versions of all modules in current directory in a format
            suitable for -r mode.
  -x url  - Specify the XML feed URL to check for updates. (default: $BASE_URL)
  -X repo - Specify a known XML feed URL by short name, see $UPDATE_XML_CONF

EOT
}

# Returns the base URL for the updates XML feed.  If an argument is passed,
# will look for an info file in the given directory and see if it has an
# overridden update URL.  This is used by the feature server.
#
# Otherwise just returns the default.
get_base_url() {
  module=$1
  if [ -n "$module" ] && [ -f "$module/$module.info" ] ; then
    override=`awk -F'"' '/^project status url/{print $2}' $module/$module.info`
    if [ -n "$override" ] ; then
      echo $override
    else
      echo $BASE_URL
    fi
  else
    echo $BASE_URL
  fi
}

symlink_module() {
  module=$1
  version=$2
  base_url=`get_base_url $module`

  if [ -z "$version" ] ; then
    # No specific version given, so just get recommended
    recommended=`xmlstarlet sel --net --text --template --match "/project/recommended_major" --value-of . --nl $base_url/$module/$CORE`

    if [ -z "$recommended" ] ; then
      echo "Can't find recommened major version for $module"
      return
    fi

    # This will grab the version string of the first release for the recommended
    # major version number
    version=`xmlstarlet sel --net --text --template --match "/project/releases/release[version_major='$recommended'][position()=1]/version" --value-of . --nl $base_url/$module/$CORE`

    if [ -z "$recommended" ] ; then
      echo "Can't find recommened version for $module major version $recommended"
      return
    fi
  fi

  target_dir=$TARGET_BASE/$module/$version
  if [ ! -d $target_dir ] ; then
    if [ $AUTODOWNLOAD -eq 1 ] ; then
      get_module $module $version
    else
      echo "$target_dir not present." 
      while read -n1 -p "Do you want to fetch $module-$version? (y/n)" answer ; do
        case $answer in
          y) echo ; get_module $module $version; break ;;
          n) echo ; return ;;
        esac
      done
    fi
  fi

  if [ -e "$module" ] ; then
    if [ ! -L "$module" ] ; then
      echo "$module exists and is not a symlink ... skipping"
      return
    else
      link=`readlink $module`
      if [ "$link" == "$target_dir" ] ; then
        echo "$module already links to $target_dir ... skipping"
        return
      else
        echo "$module currently links to $link"
        while read -n1 -p "Do you want to change it to $module-$version? (y/n)" answer ; do
          case $answer in
            y) echo ; rm -v $module ; break ;;
            n) echo ; return ;;
          esac
        done
      fi
    fi
  fi

  ln -vs $target_dir $module
}

get_module() {
  module=$1
  version=$2
  base_url=`get_base_url $module`

  if [ -z "$version" ] ; then
    # No specific version given, so just get recommended
    recommended=`xmlstarlet sel --net --text --template --match "/project/recommended_major" --value-of . --nl $base_url/$module/$CORE`

    if [ -z "$recommended" ] ; then
      echo "Can't find recommened major version for $module"
      return
    fi

    # This will grab the version string of the first release for the recommended
    # major version number
    version=`xmlstarlet sel --net --text --template --match "/project/releases/release[version_major='$recommended'][position()=1]/version" --value-of . --nl $base_url/$module/$CORE`

    if [ -z "$recommended" ] ; then
      echo "Can't find recommened version for $module major version $recommended"
      return
    fi
  fi

  target_dir=$TARGET_BASE/$module/$version
  if [ -d $target_dir ] ; then
    echo "$target_dir already present ... skipping"
    return
  fi
  url=`xmlstarlet sel --net --text --template --match "/project/releases/release[version='$version']/download_link" --value-of . --nl $base_url/$module/$CORE`
  if [ -z "$url" ] ; then
    echo "Unable to determine download URL for $module version $version"
    return
  fi
  mkdir -vp $target_dir
  echo "Downloading $module ($version) to $target_dir"
  wget --quiet -O - $url | tar -z -x -f - -C $target_dir --strip 1
}

find_update_xml_url() {
  awk -v shortname="$1" '{if($1 == shortname){print $2;exit}}' $UPDATE_XML_CONF
}


while getopts "c:b:x:X:fdlLrhvm" OPT ; do
  case $OPT in
    c)  CORE=$OPTARG ;;
    b)  TARGET_BASE=$OPTARG ;;
    x)  BASE_URL=$OPTARG ;;
    X)  BASE_URL=`find_update_xml_url $OPTARG` ;;
    l)  LIST=1 ;;
    L)  CONTRIBLIST=1 ;;
    m)  MISSING=1 ; AUTODOWNLOAD=1 ;;
    r)  READ=1 ; AUTODOWNLOAD=1 ;;
    f)  FIND=1 ;;
    d)  DOWNLOAD=1 ;;
    v)  VERSIONLIST=1 ;;
    h)  usage ; exit 0 ;;
    *)  usage ; exit 1 ;;
  esac
done

shift $(($OPTIND - 1))

if [ $READ -eq 0 ] && [ $VERSIONLIST -eq 0 ] ; then
  if [ $# -lt 1 ] && [ $READ -eq 0 ] && [ $MISSING -eq 0 ] ; then
    usage
    exit 1
  fi
fi

module=$1
version=$2

if [ $(($LIST + $READ + $FIND + $CONTRIBLIST + $VERSIONLIST + $MISSING)) -gt 1 ] ; then
  echo "Incompatible options used"
  usage
  exit 1
fi

if [ $LIST -eq 1 ] ; then
  if [ -d "$TARGET_BASE/$module" ] ; then
    echo "Available versions of $module for core $CORE:"
    ls $TARGET_BASE/$module
    exit 0
  else
    echo "$module not present in $TARGET_BASE"
    exit 1
  fi
elif [ $CONTRIBLIST -eq 1 ] ; then
  echo "Available releases of $module for core $CORE:"
  xmlstarlet sel --net --text --template --match '/project/releases/release/version' --value-of . --nl $BASE_URL/$module/$CORE
  exit 0
elif [ $READ -eq 1 ] ; then
  if [ $DOWNLOAD -eq 1 ] ; then
    while read module version ; do
      get_module $module $version
    done
  else
    while read module version ; do
      symlink_module $module $version
    done
  fi
  exit 0
elif [ $FIND -eq 1 ] ; then
  if [ -z "$version" ] ; then
    versions=`ls $TARGET_BASE/$module | xargs -n 1 basename`
  else
    versions=$version
  fi
  for version in $versions ; do
    find $CORE_BASE -lname $TARGET_BASE/$module/$version
  done
  exit 0
elif [ $DOWNLOAD -eq 1 ] ; then
  get_module $module $version
elif [ $VERSIONLIST -eq 1 ] ; then
  for module in * ; do
    if [ ! -d $module ] ; then
      echo "$module is not a directory ... skipping" >&2
      continue
    fi

    infofile="$module/$module.info"
    if [ ! -f "$infofile" ] ; then
      infofile=`find $module/ -name '*.info' | head -n 1`
      if [ -z "$infofile" ] || [ ! -f "$infofile" ] ; then
        echo "Can't find a .info file for '$module'" >&2
        continue
      fi
    fi
    echo -n $module
    awk -F= '/^version/{version=$2}END{print version}' $infofile | sed -e 's/"//g'
  done
elif [ $MISSING -eq 1 ] ; then
  for module in * ; do
    if [ ! -L $module ] ; then
      continue
    fi
    target=`readlink $module`
    if [ ! -d "$target" ] ; then
      version=`basename $target`
      dirname=`dirname $target`
      module=`basename $dirname`
      if [ -z "$module" ] || [ -z "$version" ] ; then
        echo "Can't determine module info from symlink $target" >&2
        continue
      fi
      get_module $module $version
    fi
  done
else
  symlink_module $module $version
fi