#!/bin/bash
# Magento Module Manager
# Version 0.9 (Oct 2, 2009)

# System Requirements:
# - bash
# - web server must follow symlinks
# - The following utilities must be locatable in your $PATH
#     svn, grep (POSIX), find, ln, sed, cp, basename, dirname

script=${0##*/}
usage="
----------------------
Magento Module Manager
----------------------
Usage: $script <module> <action> [svn args]
Supported global actions (no module specified):
  init           initialize the current directory as the modman root (no module name)
  update-all     update all modules that are currently checked out

Supported actions: (all svn commands support additional arguments)
  checkout       checkout a new modman compatible module
  export         export a modman compatible module (does real copy instead of symlinks)
  update [...]   update module
  add <svn_path> <real_path>   add a file/dir to the .modman file and working copy
  delete <svn_path>   remove a file/dir from the .modman file and working copy
  status         show status of entire module
  diff [...]     run svn diff on module
  commit [...]   commit changes to module
  info           show the module's working copy path and run svn info on working copy
  list           list the definitions in the .modman file

The repository should contain a file called \".modman\" which defines which files
go where relative to the directory where modman was initialized.

If additional arguments are given to commands such as commit, paths
should be relative to the svn root.

---- Start example .modman file ----
# Comments are supported, begin a line with a hash
code                   app/code/local/My/Module/
design                 app/design/frontend/default/default/mymodule/
locale/My_Module.xml   app/locale/en_US/My_Module.xml
My_Module.xml          app/etc/modules/My_Module.xml
---- End example .modman file ----

Author:
Colin Mollenhour
http://colin.mollenhour.com/
colin@mollenhour.com
"

# bash implementation of realpath / readlink -f
# arg1 - filename
realpath()
{
	fname=${1%/} # strips trailing '/'
	while [ -L "$fname" ]; do
	 oldfname="$fname"
	 fname="$(command ls -l $fname)"
	 fname="${fname#*> }"
	 if [ "$fname" = . ] ; then
	 fname="$(dirname $oldfname)"
	 elif echo $fname | grep -vq '^/' - ; then
	 fname="$(dirname $oldfname)/$fname"
	 fi
	done
	pushd $(dirname $fname) > /dev/null
	fname=$(pwd -P)/$(basename $fname)
	popd > /dev/null
	echo $fname
}


# Handle "init" command, simply create .modman directory
if [ "$1" = "init" ]; then
  mkdir .modman && echo "Initialized Module Manager at `pwd`"
  exit 0
fi

# Find the .modman directory and store parent path in $root
_pwd=$(realpath `pwd`)

rel=''
mm_not_found="Module Manager directory not found.\nRun \"$script init\" in the web root of the Magento installation with which you would like to use Module Manager."
root=$_pwd
while ! [ -d $root/.modman ]; do
  if [ "$root" = "/" ]; then echo -e $mm_not_found && exit 1; fi
  rel=${root##*/}/$rel
  cd .. || (echo -e "ERROR: Could not traverse up from $root\n$mm_not_found" && exit 1)
  root=`pwd`
done

mm_dir=$root/.modman      # path to .modman

# Handle "update-all" command
if [ "$1" = "update-all" ]; then
  if [ -n "$2" ]; then echo "Too many arguments to update-all command"; exit 1; fi
  for module in `ls $mm_dir`; do
    $0 $module update || exit 1
  done
  echo "Successfully updated all modules."
  exit 0
fi

module=$1; shift          # module name
wc_dir=$mm_dir/$module    # working copy directory for module
wc_desc=$wc_dir/.modman   # path to modman structure descriptor file

action=$1; shift          # svn command to be used

if [ -z "$module" ]; then
  echo -e "Not enough arguments (no module specified)\n$usage" && exit 1
fi
if [ -z "$action" ]; then
  echo -e "Not enough arguments (no action specified)\n$usage" && exit 1
fi

if [ "$1" == "--force" ]; then
  FORCE="1"; shift
else
  FORCE="0"
fi

cd $_pwd; #restore old root

require_wc ()
{
  if ! [ -d $wc_dir ]; then
    echo "ERROR: The '$module' module has not been checked out."; exit 1
  fi
  if ! [ -r $wc_desc ]; then
    echo "ERROR: The '$module' module does not contain a .modman module description file."; exit 1
  fi
  return 0
}

create_links ()
{
  grep -v '^#' $wc_desc | \
  while read svn real; do
    src=$wc_dir/$svn
    dest=$root/${real%/}
    # Handle aliases that do not exist
    if ! [ -e $src ]; then
      if [ -L $dest ]; then
        rm $dest && echo "Removed bad link to $real"
      fi
      echo "WARNING: Alias described in .modman does not exist in working copy: $svn"
      continue
    fi

    # Handle cases where files already exist at the destination
    if [ -e $dest ] && ! [ -L $dest ]; then
      if [ "$FORCE" == "0" ]; then
        echo -e "CONFLICT: $real already exists and is not a link.\nRun with --force to force removal of existing files."
        return 1
      else
        rm -rf $dest
      fi
    fi

    # Create links if they do not already exist
    if ! [ -e $dest ]; then
      mkdir -p ${dest%/*}
      if ln -s $src $dest
      then
        echo "Created link for new module directive: $svn $real"
      else
        echo -e "Unable to create softlink for rule: $svn $real"
        return 1
      fi
    fi
  done
  # remove dead symlinks
  find -L $root -type l -delete
  return 0
}

copy_over ()
{
  grep -v '^#' $wc_desc | \
  while read svn real; do
    cp -r $wc_dir/$svn $root/${real%/} || return 1
  done
  return 0
}

case "$action" in

  status)
    require_wc
    cd $wc_dir
    svn status $@
    ;;

  diff)
    require_wc
    cd $wc_dir
    svn diff $@
    ;;

  info)
    require_wc
    cd $wc_dir
    echo "$wc_dir"
    svn info $@
    ;;

  commit)
    require_wc
    cd $wc_dir
    sed --in-place -e '/^$/d' $wc_desc
    svn commit $@
    ;;

  update)
    require_wc
    cd $wc_dir
    cp .modman .modman-old
    svn update $@ || (echo "failed to update working copy"; rm .modman-old; exit 1)

    #remove any links that were removed from .modman file
    grep -F -vxf .modman .modman-old | grep -v '^#' | \
    while read svn real; do
      if [ -L $root/$real ]; then
        rm $root/${real%/}
      fi
    done
    rm .modman-old

    create_links && echo "Update of module $module complete."
    ;;

  add)
    require_wc
    svn=$1; shift
    real=$1; shift
    if [ -z $svn ]; then echo -e "Not enough arguments to \"add\".\n$usage"; exit 1; fi
    if [ -z $real ] || ! [ -e $root/$real ]; then echo "Real path not specified or not found ($real)"; exit 1; fi
    cd $wc_dir
    if [ "`dirname $svn`" -ne "." ]; then mkdir -p `dirname $svn`; fi
    mv $root/$real $wc_dir/$svn || (echo "Could not move $root/$real to $wc_dir/$svn, make sure the files are closed."; exit 1)
    if
      svn add --parents $@ $svn &&
      cat "$svn $real" >> $wc_desc &&
      ln -s $wc_dir/$svn $root/${real%/}
    then
      echo "Scheduled add of $real under svn alias $svn"
      create_links
    else
      echo "An error occurred while trying to add $real under svn alias $svn"
    fi
    ;;

  delete)
    require_wc
    cd $wc_dir
    svn=$1; shift
    if [ -z $svn ]; then echo -e "You must specify an alias to delete.\n$usage"; exit 1; fi
    if [ `grep -c "'^$svn '" < $wc_desc` != "1" ]; then
      echo "Alias rule not found for '$svn'"; exit 1
    fi
    if
      svn delete $@ &&
      sed --in-place -e "'\\#^$svn #d'" $wc_desc
    then
      echo "Scheduled delete of svn alias $svn"
    else
      echo "An error occurred while trying to remove svn alias $svn"
    fi
    ;;

  checkout)
    cd $mm_dir
    if [ -d $wc_dir ]; then
      echo "A module by that name has already been checked out"; exit 1
    fi
    if
      svn checkout $@ $module &&
      require_wc &&
      create_links
    then
      echo "Checkout of module $module complete"
    else
      if [ -d $wc_dir ]; then rm -rf $wc_dir; fi
      echo "Error checking out $module, operation cancelled."
    fi
    ;;

  list)
    require_wc
    echo "--Module Manager alias definitions for $module module:"
    cat $wc_desc
    ;;

  export)
    cd $mm_dir
    if [ -d $wc_dir ]; then
      echo "You cannot export a module that has already been checked out"; exit 1
    fi
    if
      svn export $@ $module &&
      require_wc &&
      copy_over
    then
      echo "Exported $module to $root"
    else
      if [ -d $wc_dir ]; then rm -rf $wc_dir; fi
      echo "Failed to export module to $root"
    fi
    ;;

  *)
    echo -e "$usage\nInvalid action: $action\n";
    exit;

esac