#!/bin/bash

# PURPOSE
# This is not a nightly script. You use it to regenerate the model-collections
# if Greenstone has changed fundamentally, such as what HASH OIDs get assigned
# to documents or something that changes the contents of the index and 
# archives folders. This has happened now with the commits 
# http://trac.greenstone.org/changeset/28022 and 
# http://trac.greenstone.org/changeset/28021
# These commits generate new stable HASH OIDs for the existing documents.


# USAGE
# Put this file in the toplevel of the Greenstone 2 binary/compiled SVN installation
# that you want to generate the model collections with.
# You can provide a list of collection names or none, in which case all the collections
# are processed.

# Pass in --svnupdate to copy across the contents of archives and index in the
# rebuilt collection, overwriting their equivalents in the svn model collection,
# but not removing any extraneous HASH folders already present.

# Pass in --svndelete to remove what's in archives and index from svn and replace
# the contents of archives and index with the matching contents from the rebuild 
# collection. Useful for when the HASH directory naming has changed and everything
# in archives and index has to be wiped out and moved back in from the rebuilt col.

# If neither is passed in, then the collections are rebuilt but the svn model-collect
# is not updated and the repository is not updated.

# This program leaves you to do the final commit on the (svn) model-collect folder!

# Examples of usage:
# ./gen-model-colls.sh
# ./gen-model-colls.sh --svndelete
# ./gen-model-colls.sh --svnupdate Tudor-Basic Tudor-Enhanced

# The first just rebuilds all the collections in a new folder called collect and stops there
# The second rebuilds all the collections and then removes all contents of the archives and the
# index folders from the svn checked-out model-collect and removes them from svn. Then it copies 
# across all the contents of the rebuilt archives and index into model-collect and svn adds them.
# The third example checks out all the model-collections again, but rebuilds only the 3 collections 
# specified in the new collect folder. Then it copies across the contents of the archives and index
# folders of those 3 collections into their model-collect equivalents.

# You then still have to do the final svn commit on the model-collect folder.

# Also valid examples:
# ./gen-model-colls.sh Tudor-Basic Tudor-Enhanced
# ./gen-model-colls.sh --svndelete Tudor-Basic Tudor-Enhanced
# ./gen-model-colls.sh --svnupdate

# PSEUDOCODE
# This script:
# Checks out the model-collections folder from SVN 
# Makes a copy
# In the copy: gets rid of their .svn folders, and builds each collection in turn, moving building to index once done
# If --svndelete was passed in: svn removes model-collect/archives/* and model-collect/index/*, copies over index/* 
# and archives/* from collect into model-collect and svn adds model-collect/archives/* and model-collect/index/*
# If --svnupdate was passed in: copies collect/archives/* into model-collect/archives/*, and copies collect/index/*
# into model-collect/index/*, overwriting files that already existed but have now been updated upon rebuild. However, 
# --svnupdate will leave untouched any files and folders unique to model-collect.

# svn update/delete a single collection
function update_single_collection () {
    collection=$1
    mode=$2

    #escape the filename (in case of space)
    collection=`echo $collection | sed 's@ @\\\ @g'`
    
    #get just the basename
    collection=`basename $collection`

    if [ ! -e model-collect/$collection ]; then
	echo "$collection does not exist in model-collect, commit separately"
	return;
    fi

    # diff the svn model and rebuilt model collections
    diff_result=`diff -rq model-collect/$collection collect/$collection | grep -v ".svn"`
#    echo "Diff result for collection $collection: $diff_result"

    # if no differences in the current collection, then we're done
    if [ "x$diff_result" == "x" ]; then
	echo "No differences in collection $collection"
	return;
    fi

    # check that none of the lines mention files outside the archives or index folders
    # http://en.gibney.org/tell_the_bash_to_split_by_newline_charac
    # http://forums.gentoo.org/viewtopic-p-3130541.html

    # http://wi-fizzle.com/article/276
    # http://stackoverflow.com/questions/918886/how-do-i-split-a-string-on-a-delimiter-in-bash
    # http://www.linuxquestions.org/questions/programming-9/split-a-string-on-newlines-bash-313206/
    # http://unix.stackexchange.com/questions/39473/command-substitution-splitting-on-newline-but-not-space

    # store backup of Internal Field Separator value, then set IFS to newline for splitting on newline

    IFS_BAK=$IFS
#    IFS='\n' # splits on all whitespace
IFS='
'
    # in the lines returned from the diff, test for archives or newline
    # http://stackoverflow.com/questions/229551/string-contains-in-bash
    for line in `diff -rq model-collect/$collection collect/$collection | grep -v ".svn"`; do
	# echo "LINE: $line"	
	if [[ "$line" != *archives* && "$line" != *index* ]]; then
	    # the file that is different is neither in index nor in archives, send this diffline to the report
	    echo $line >> report.txt
	fi
    done
 
    IFS=$IFS_BAK
    IFS_BAK=

    # Now svn remove what's unique to model-collect and svn add what's been rebuilt in index and archives
    # see # http://stackoverflow.com/questions/7502261/delete-folder-content-and-remove-from-version-control
 
    if [ "$mode" == "svndelete" ]; then
	svn rm model-collect/$collection/archives/*
	svn rm model-collect/$collection/index/*
    fi

    # copy across the contents of the rebuilt model-collection's index and archives to the svn model-collect
    cp -r collect/$collection/archives/* model-collect/$collection/archives/.
    cp -r collect/$collection/index/* model-collect/$collection/index/.

    if [ "$mode" == "svndelete" ]; then
	svn add model-collect/$collection/archives/*
	svn add model-collect/$collection/index/*
    fi

    # To undo the changes made by svndelete, run the following manually
    # svn revert --depth infinity <model-collect/$collection/archives/*
    # svn revert --depth infinity <model-collect/$collection/archives/*
    # then remove both the local archives and index, and do an svn up to get original checkout back

    # if etc/collect.cfg is different, copy it across too?


}

# re-build a single collection in "collect" which is a copy of model-collect
function single_collection () {
    collection=$1    

    #escape the filename (in case of space)
    collection=`echo $collection | sed 's@ @\\\ @g'`
    
    #get just the basename
    collection=`basename $collection`
    
    import.pl -removeold $collection
    buildcol.pl -removeold $collection
    rm -rf collect/$collection/index
    mv collect/$collection/building collect/$collection/index
    
    echo
    echo "*********************"
    echo "Done processing $collection"
    echo "*********************"
    echo
}

# unused
# re-build all collections in "collect" which is a copy of model-collect
function all_collections() {

    #for each collection, import, build, move building to index
    for collection in collect/*; do
	single_collection $collection;
	#update_single_collection $collection;
    done
}

# http://stackoverflow.com/questions/16483119/example-of-how-to-use-getopt-in-bash
function usage() { 
# usage() { echo "Usage: $0 [-s <45|90>] [-p <string>]" 1>&2; exit 1; }

    echo "*******************************************"
    echo "Usage: $0 [--svnupdate|--svndelete] [col1, col2, col3,...]"; 
    echo "If no collections are provided, all collections will be processed.";
    echo "If neither svnupdate nor svndelete are provided, svnupdate is assumed.";
    echo "*******************************************"
    exit 1; 
}


# The program starts here

# process optional command line arguments
# http://blog.onetechnical.com/2012/07/16/bash-getopt-versus-getopts/
# Execute getopt
ARGS=$(getopt -o ud -l "svnupdate,svndelete" -n "$0" -- "$@");

#Bad arguments
if [ $? -ne 0 ];then
    usage
    exit 1
fi

eval set -- "$ARGS";

# mode can be svndelete or svnupdate
mode=

# -n: http://tldp.org/LDP/abs/html/testconstructs.html
while true; do
  case "$1" in
    -d|--svndelete)
      shift;
      if [ "x$mode" == "xsvnupdate" ]; then
	  echo
	  echo "Can't use both svndelete and svnupdate"
	  usage
	  exit 1
      else
	  mode=svndelete
      fi
      ;;
    -u|--svnupdate)
      shift;
      if [ "x$mode" == "xsvndelete" ]; then
	  echo
	  echo "Can't use both svndelete and svnupdate"
	  usage
	  exit 1
      else
	  mode=svnupdate
      fi
      ;;
    --)
      shift;
      break;
      ;;
  esac
done

# If no mode provided (svndelete|svnupdate) as cmd line arg, then don't modify
# the svn model-collect folder. We leave it at rebuilding its copy in collect

#http://www.cyberciti.biz/faq/linux-unix-sleep-bash-scripting/
#if [ "x$mode" == "x" ]; then
#    echo
#    echo "***Mode svndelete or svnupdate not provided. Defaulting to svnupdate... 3s to change to your mind"
#    echo
#    sleep 3s
#    mode=svnupdate
#fi

# the remaining arguments to the script are assumed to be collections

# debugging
#for collection in "$@"; do
#    collection=collect/$collection
#    echo "Collection: $collection"
#done

# finished processing arguments


# report will contain the output of the diff for
if [ -f report.txt ]; then
    rm report.txt
fi

# Need pdfbox for the PDFBox tutorial
if [ ! -e ext/pdf-box ]; then
    cd ext
    if [ ! -e ext/pdf-box-java.tar.gz ]; then
	wget http://trac.greenstone.org/export/head/gs2-extensions/pdf-box/trunk/pdf-box-java.tar.gz
	tar -xvzf pdf-box-java.tar.gz
    fi
    cd ..
fi


if test -e model-collect; then   
    svn up model-collect
else
    svn co http://svn.greenstone.org/other-projects/nightly-tasks/diffcol/trunk/model-collect
fi

# move the existing collect folder out of the way
if [ -e collect ] && [ ! -e collect_orig ] ; then
    mv collect collect_orig
fi

# make a copy of the model-collect named as the new collect 
# and remove the copy's .svn folders
if [ -e collect_orig ]; then
    if [ -e collect ]; then
	rm -rf collect
    fi
    cp -r model-collect collect
fi

#cd collect
#find . -name ".svn" -type d -exec rm -rf {} \;
#cd ..
find collect -name ".svn" -type d -exec rm -rf {} \; #2>&1 > /dev/null


# Set up the Greenstone environment for building
source setup.bash

# parse arguments
# http://stackoverflow.com/questions/12711786/bash-convert-command-line-arguments-into-array
# http://stackoverflow.com/questions/255898/how-to-iterate-over-arguments-in-bash-script

if [ "$1" == "" ]; then
	# all_collections	
    #for each collection, import, build, move building to index
    for collection in collect/*; do
	single_collection $collection;
	if [ "x$mode" != "x" ]; then
	    update_single_collection $collection $mode;
	fi
    done
else
    # Command-line args are a list of collections, 
    # process each command-line arg, after confirming such a collection exists

    for collection in "$@"; do
	collection=collect/$collection
	if test -e $collection; then   
	    single_collection $collection;
	    if [ "x$mode" != "x" ]; then
		update_single_collection $collection $mode;
	    fi
	else
	    echo "Can't find collection $collection. Skipping."
	fi
    done
fi


echo
echo "*****************************************"
# if we were svn updating/deleting collections, then mode was set
# if in that case a report was generated with additional differences, point the user to it
if [ -f report.txt ] && [ "x$mode" != "x" ]; then
    echo "Some files outside of archives and index folders were different. See report.txt"
    echo
fi

echo "The original collect directory has been left renamed as collect_orig"
echo
if [ "x$mode" == "x" ]; then
    echo "The model-collect folder has not been altered. Changes have only been made to collect"
else
    echo "You still need to run svn status and svn commit on the model-collect folder"
fi
echo "*****************************************"
echo