#!@PMODULES_HOME@/bin/bash

# we have to unset CDPATH, otherwise 'cd' prints the directoy!
unset CDPATH

# used for some output only
declare -r  CMD=$(basename "$0")

declare -r  mydir=$(cd $(dirname "$0") && pwd)
declare -r  prefix=$(dirname "${mydir}")
declare -r  bindir="${prefix}/bin"
declare -r  libdir="${prefix}/lib"
declare -r  libexecdir="${prefix}/libexec"

source "${libdir}/libpmodules.bash"

PATH="${bindir}:${PATH}"

_exit () {
	std::die 1 "Interrupted..."
}

_err () {
	std::info "Oops: got an error in function '${FUNCNAME[1]}', line ${BASH_LINENO[0]}"
	std::die 1 "Aborting ..."
}

trap '_exit' INT TERM
trap '_err' ERR


# make sure that everything is used from this version
declare PMODULES_VERSION='@PMODULES_VERSION@'

print_version() {
	echo "
Pmodules @PMODULES_VERSION@ using Tcl Environment Modules @MODULES_VERSION@
Copyright GNU GPL v2
" 1>&2
}

usage() {
	local -r prog=$(basename $0)
	print_version
	echo "
Usage: ${prog} [ switches ] [ subcommand ] [subcommand-args ]

Switches:
        --dry-run     do nothing
        --force       force overwrite

Available SubCommands and Args:
        init [--src=<src>] [--user=<user>] <dst>
                Initialize a new minimal Pmodule environment.

        install <module> [--with=<dep>...]
                Install matching modules

        sync [--delete] [--dst=<dst>] <src>
                Synchronize modules.
"
}

declare force='no'
declare dry_run='no'
declare DRY=''
declare subcommand=''
declare sargs=()

subcommand_help_init() {
	echo "
init [--src=<src>] [--user=<user>] [--version=<version>] <dst>
                Initialize a new minimal Pmodule environment in directory
                <dst>. The <user> parameter must only be present if
                 ${prog} is executed as root.
" 1>&2
}

subcommand_help_install() {
	echo "
install <module>... [--with=<dep>...] [--release=<release>...] [--src=<src>]
                Install matching modules
" 1>&2
}

subcommand_help_sync() {
	echo "
sync [--delete] [--dst=<dst>] <src>
                Synchronize environment modules and configuration files
                from Pmodule environment <src> to Pmodule environment <dst>
                (default: currently active Pmodule environment).
                Not yet implemented:
                If --delete is given, unmarked modules present in <dst>
                will be deleted.
" 1>&2
}

subcommand_help() {
	if [[ $# == 0 ]]; then
	        usage
	elif typeset -F subcommand_help_$1 > /dev/null 2>&1 ; then
	        # help for sub-command
		subcommand_help_$1
	else
		usage
	fi
}

#
# Derive the relative module installation path
# from the relative modulefile path
#
# $1: relative module file path
#
get_module_prefix() {
	local -a comp=( ${1//\// } )    # split rel.path into components
	local path="${comp[0]}"		# result path
	local -i i
	for ((i=1; i<${#comp[@]}-1; i+=2)); do
		path+="/${comp[$((-i-1))]}/${comp[$((-i))]}"
	done
	echo "${path}"
}

#
# Derive the relative module release file path
# from the relative module file path
#
# $1: relative module file path
#
get_releasefile_name() {
	echo "$(dirname "$1")/.release-$(basename "$1")"
}

#
# Sync a module from one Pmodules environment to another:
# - sync module installation
# - sync modulefile
# - sync release file
#
# Note:
#   We do not take care of files in $PMODULES_ROOT/$PMODULES_TEMPLATES_DIR. If
#   the modulefile is a sym-link it is expected that the target exists.
#
# $1: relative modulefile path (something like: Tools/gnuplot/5.0.0)
# $2: source prefix of Pmodule environment
# $3: target prefix of Pmodule environment
#
sync_module() {
	local -r rel_modulefile=$1
	local -r src_prefix=$2
	local -r target_prefix=$3

	local -r rel_module_prefix=$( get_module_prefix "${rel_modulefile}" )
	local -r rel_releasefile=$( get_releasefile_name "${rel_modulefile}" )

	# install/update module
	if [[ ! -d "${target_prefix}/${rel_module_prefix}" ]] || [[ "${force}" == 'yes' ]]; then
		$DRY mkdir -p "${target_prefix}/${rel_module_prefix}" || return $?
		$DRY rsync --links --perms --recursive --delete \
		      "${src_prefix}/${rel_module_prefix}/" \
		      "${target_prefix}/${rel_module_prefix}/" 2>/dev/null || return $?
	fi
	local -r src_modulefile="${src_prefix}/${rel_modulefile}"
	local -r src_releasefile="${src_prefix}/${rel_releasefile}"
	local -r target_modulefile="${target_prefix}/${rel_modulefile}"
	local -r target_releasefile="${target_prefix}/${rel_releasefile}"

	# create target directory for module- and release-file
	if [[ -e "${src_modulefile}" ]] || [[ -e "${src_releasefile}" ]]; then
	        local dir=$( dirname "${target_modulefile}" )
		$DRY mkdir -p "${dir}" || return $?
	fi

	# copy modulefile
	if [[ -e "${src_modulefile}" ]]; then
	        $DRY rsync --links --perms --recursive \
		     "${src_modulefile}" "${target_modulefile}" 2>/dev/null || return $?
	fi

	# copy release-file
	if [[ -e "${src_releasefile}" ]]; then
	        $DRY rsync --links --perms --recursive \
		     "${src_releasefile}" "${target_releasefile}" 2>/dev/null|| return $?
	fi
}

#
# Sync the Pmodules configuration and templates
#
# $1: source prefix of Pmodule environment
# $2: target prefix of Pmodule environment
#
sync_config() {
	src="$1/${PMODULES_CONFIG_DIR}/"
	dst="$2/${PMODULES_CONFIG_DIR}/"
	$DRY rsync --recursive --links --perms --delete \
		"${src}" "${dst}" 2>/dev/null || return $?
	sed -i.bak "s/PMODULES_VERSION=\(.*\)/PMODULES_VERSION=${PMODULES_VERSION}/" "${dst}/environment.bash"
	echo

	src="$1/${PMODULES_TEMPLATES_DIR}/"
	dst="$2/${PMODULES_TEMPLATES_DIR}/"
	$DRY rsync --recursive --links --perms --delete --exclude="${src}/.git*" \
		"${src}" "${dst}" 2>/dev/null || return $?
	echo
}

#
# Delete a module
#
# $1: relative modulefile path
# $2: target prefix of Pmodule environment
#
delete_module() {
        echo "Not implemented yet!"
}

subcommand_init() {
	local src=''
	local target_prefixes=()
	local user=''
	local opts=''
	opts=$(pmodules::get_options -o h -l src: -l user: -l help -l version: -- "$@")
	if [[ $? != 0 ]]; then
		subcommand_help_init
		exit 1
	fi
	eval set --  "${opts}"
	while (($# > 0)); do
		case $1 in
			--src )
				src=$2
				shift
				;;
			--user )
				user=$2
				shift
				;;
			--version )
				PMODULES_VERSION=$2
				shift
				;;
			-- )
				:
				;;
			-* | -h | --help )
				echo "$1: illegal option" 1>&2
				subcommand_help_init
				exit 1
				;;
			* )
				target_prefixes+=( "$1" )
				;;
		esac
		shift
	done
	(( ${#target_prefixes[@]} != 0 )) || \
		std::die 1 "Error: no target directory specified!"

	# if source directory is not passed as argument, derive it from script name
	if [[ -z "${src}" ]]; then
	    src=$(cd "${bindir}/../../../.." && pwd) 
	fi
	[[ -d "${src}" ]] || \
		std::die 1 "Error: ${src}: source directory does not exist!"
	[[ -r "${src}/config/profile.bash" ]] || \
		std::die 1 "Error: ${src}: shell profile does not exist or is not readable!"
	source "${src}/config/profile.bash"

	local -i euid=$(id -u)
	if (( euid == 0 )); then
	        [[ -n "${user}" ]] || \
		    std::die 1 "Error: --user parameter is required!"
		id -u "${user}" > /dev/null 2>&1 || \
		    std::die 1 "Error: Unable to retrieve user id of user '${user}'"
	else
		[[ -z "${user}" ]] || \
		    std::die 1 "Error: --user option is only allowed if running as root!"
	fi

	pmodules::check_env || \
		std::die 1 "Giving up..."

	echo "
Attempting to create a minimal module environment from the
environment at '${PMODULES_ROOT}'
"

	init_pmodules_environment() {
		local -r src_prefix="${PMODULES_ROOT}"
		local -r target_prefix=$1
		local src=''
		local dst=''
		echo "Initializing target directory '${target_prefix}' ..."
		echo
		if [[ -d "${target_prefix}" ]]  && [[ ${force} == no ]]; then
			echo "Warning: ${target_prefix} already exists."
			std::get_YN_answer "Do you really want to re-run the initialization? (y/N) " || \
			        std::die 1 "Abort ..."
		fi
		force='yes'
		echo "Creating target directory '${target_prefix}'..."
		$DRY mkdir -p "${target_prefix}" || \
		        std::die 1 "Error: make directory failed!"
		echo

		echo "Syncing configuration ..."
		sync_config "${PMODULES_ROOT}" \
		            "${target_prefix}" || \
		        std::die 1 "Error: configuration synchronization failed!"

		echo "Syncing Pmodules ${PMODULES_VERSION} from '${src_prefix}' to '${target_prefix}'..."
		sync_module "Tools/Pmodules/${PMODULES_VERSION}" \
			    "${src_prefix}" \
			    "${target_prefix}" || \
		        std::die 1 "Error: sync Pmodules failed!"
		mkdir -p "${target_prefix}/Tools/${PMODULES_MODULEFILES_DIR}"
		echo

		dst="${target_prefix}/${PMODULES_CONFIG_DIR}/environment.bash"
		echo "Adding installation source '${src_prefix}' to '${dst}'..."
		sed -i.bak '/PMODULES_INSTALL_SOURCE/d' "${dst}"
		echo "declare -x PMODULES_INSTALL_SOURCE=\"${src_prefix}\"" >> "${dst}"
		echo

		if [[ -n "${user}" ]]; then
	                echo "Changing user of new module environment to '${user}'..."
                        $DRY chown -R "${user}" "${target_prefix}" || \
			        std::die 1 "Error: changing owner failed!"
                        echo
		fi
		echo "New minimal module environment created at '${target_prefix}'."
		echo "To use this environment, execute"
		echo "   sudo ln -fs ${target_prefix} /opt/psi"
		echo "   source /opt/psi/${PMODULES_CONFIG_DIR}/profile.bash"
	}

	umask 022
	for target_prefix in "${target_prefixes[@]}"; do
		init_pmodules_environment "${target_prefix}"
	done

}

declare -a Groups=()
declare -A HierarchyDepths

get_groups () {
	local -r root="$1"
	{
		cd "${root}" 
		# for some unknown reason [A-Z]* doesn't work on (some?) SL6 systems
		for f in [ABCDEFGHIJKLMNOPQRSTUVWXYZ]*; do
			[[  -d ${f}/${PMODULES_MODULEFILES_DIR} ]] || continue
			Groups+=( $f )
		done
	};
}

#
# $1: root of modulefile hierarchy
get_hierarchy_depth () {
	local -r root="$1"
	local -a modulefiles_dir
	std::split_fname modulefiles_dir "${PMODULES_MODULEFILES_DIR}"
	local -ir off=$(( ${#modulefiles_dir[@]} + 3 ))
	{
		cd "${root}"
		local group
		for group in "${Groups[@]}"; do
			local  fname=$(find "${group}/${PMODULES_MODULEFILES_DIR}" \
					    -depth \( -type f -o -type l \) -print -quit)
			[[ -n ${fname} ]] || continue
			#local -a tmp2=( ${fname//\// } )
			local -a tmp
			std::split_fname tmp "${fname}"
			(( HierarchyDepths[$group]=${#tmp[@]}-off ))
		done
	};
}

subcommand_install() {
	local	    opts=''
	local -a    with=()
	local -a    releases=()
	local -a    module_pattern=()
	local	    src_prefix="${PMODULES_INSTALL_SOURCE}"
	local -r    target_prefix="${PMODULES_ROOT}"
	local	    modulefile=''
	local -A    modules_to_install
	local -A    dependencies_to_install
	local -A    map_to_family
	local -a    initial_modulepath=()

	#
	# Resolve dependencies to given module
	#
	# $1: modulefile relativ to src prefix. Something like:
	#     MPI/modulefiles/gcc/4.9.2/openmpi/1.8.4/hdf5/1.8.14
	#
	# Notes:
	#   The variables
	#	initial_modulepath
	#	modules_to_install
	#	map_to_family
	#   from the calling function are used!
	#
	resolve_dependencies_of_module () {
	 	local -r modulefile=$1
		local -a modulepath=( "${initial_modulepath[@]}" )

		# compute filename with dependencies of given module
		local -i i=0 n=0
		std::split_fname items n "${modulefile}"
		local fname_dependencies="${src_prefix}/${items[0]}"
		for (( i = n-2; i >= 2; i-=2 )); do
			fname_dependencies+="/${items[$i]}/${items[i+1]}"
		done
		fname_dependencies+='/.dependencies'
		[[ -r ${fname_dependencies} ]] || return 0

		# loop over all dependecies
		local dep
		while read dep; do
			# skip empty lines
			# :FIXME: skip comments?!
			[[ -z ${dep} ]] && continue

			# search for module with current modulepath and remember
			local modulename=$(find "${modulepath[@]}" -path "*/${dep}" 2>/dev/null | head -n 1 )
			[[ -n ${modulename} ]] || \
			        std::die 3 "Oops: required module '${dep}' not found!"
			modulename=${modulename/${src_prefix}\/}
			dependencies_to_install[${modulename}]='.'
			resolve_dependencies_of_module "${modulename}"
			# append new node in hierarchy to modulepath
			if [[ -n ${map_to_family[${dep}]} ]]; then
				local path="${src_prefix}/${map_to_family[${dep}]}/${PMODULES_MODULEFILES_DIR}/"
				path+="${modulename/*\/${PMODULES_MODULEFILES_DIR}\/}"
				modulepath+=( "${path}" )
			fi
		done < "${fname_dependencies}"
	}

	print_modules_to_install() {
		local modulefile
		std::info "The following modules will be installed/updated:"
		for modulefile in "${!modules_to_install[@]}"; do
			if [[ -e "${target_prefix}/${modulefile}" ]]; then
				std::info "    Updating: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
			else
				std::info "    Installing: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
			fi
		done 2>&1 | sort
		if (( ${#dependencies_to_install[@]} > 0 )); then
			std::info "\nThe following dependencies will be installed/updated:"
			for modulefile in "${!dependencies_to_install[@]}"; do
				if [[ -e "${target_prefix}/${modulefile}" ]]; then
					std::info "    Updating: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
				else
					std::info "    Installing: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
				fi
			done 2>&1 | sort
		fi
		std::info ""
		std::get_YN_answer "Do you want to continue? [n] " || \
			std::die 1 "Aborting..."
		std::info ""
	}
	
	opts=$(pmodules::get_options -o hf -l dry-run -l force -l with: -l release: -l help -l src: -- "$@")
	if [[ $? != 0 ]]; then
		subcommand_help_install
		exit 1
	fi
	eval set --  "${opts}"
	while (($# > 0)); do
		case $1 in
			--dry-run )
				DRY='echo'
				;;
			--force | -f )
				force='yes'
				;;
			--release )
				releases+=( "$2" )
				shift
				;;
			--src )
				src_prefix="$2"
				shift
				;;
			--with )
				with+=( "$2" )
				shift
				;;
			-- )
				:
				;;
			-h | --help )
				subcommand_help_install
				exit 1
				;;
			-* )
				echo "$1: illegal option" 1>&2
				subcommand_help_init
				exit 1
				;;
			* )
				module_pattern+=( "$1" )
				;;
		esac
		shift
	done

	[[ -n ${src_prefix} ]] \
		|| std::die 3 "Oops: no installation source given."
	[[ -d ${src_prefix} ]] \
		|| std::die 3 "Oops: '${src_prefix}' is not a valid installation source."

	# scan available groups and their depth
	get_groups "${src_prefix}"
	get_hierarchy_depth "${src_prefix}"

	# set initial modulepath
	local group
	for  group in "${!HierarchyDepths[@]}"; do
		if (( ${HierarchyDepths[${group}]} == 0 )); then
			initial_modulepath+=( "${src_prefix}/${group}/${PMODULES_MODULEFILES_DIR}" )
		fi
	done

	#
	# create a mapping from module name to their family.
	# Examples:
	#     gcc/5.2.0 -> Compiler
	#     openmpi/1.8.4 -> MPI
	local    _fname=''	
	while read _fname; do
		local _family="${_fname%/${PMODULES_MODULEFILES_DIR}/*}"
		local -a items
		std::split_fname items "${_fname#*/${PMODULES_MODULEFILES_DIR}/}"
		local -i n=${#items[*]}
		# We are only interested in families adding something to
		# the modulepath. 
		if (( n >= 4 )); then
			local _key=$( IFS='/'; echo "${items[*]:$n-4:2}" )
			map_to_family[$_key]=${_family}
		fi
	done < <({ cd "${src_prefix}" && \
				 find */"${PMODULES_MODULEFILES_DIR}" \
				      \( -type l -o -type f \) \! -name ".*"; } 2>/dev/null )

	#
	# search for to be installed modules and their dependencies
	#
	local -i n=0
	while read modulefile; do
		resolve_dependencies_of_module "${modulefile}"
		modules_to_install["${modulefile}"]+='.'
		let n+=1
	done < <(${PMODULES_HOME}/bin/modulecmd bash search \
				 "${module_pattern[@]}" \
				 "${with[@]/#/--with=}" \
				 "${releases[@]/#/--release=}" \
				 --no-header --print-modulefiles \
				 --src="${src_prefix}"  2>&1 1>/dev/null)
	(( n == 0 )) && \
		std::die 0 "No matching modules found ..."
	print_modules_to_install

	# install ...
	for modulefile in "${!modules_to_install[@]}" "${!dependencies_to_install[@]}"; do
		if [[ -e "${target_prefix}/${modulefile}" ]]; then
			std::info "    Updating: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
		else
			std::info "    Installing: ${modulefile/\/${PMODULES_MODULEFILES_DIR}\//: }"
		fi
		sync_module "${modulefile}" \
			    "${src_prefix}" \
			    "${target_prefix}"
	done
	std::info "\nDone!\n"
}

#
# delete specified module(s)
#
subcommand_delete() {
	:
}

#
# remove modules which have been removed in our source
#
subcommand_cleanup() {
	:
}

subcommand_sync() {
	local delete=false
	local opts=''
	local dst_prefix=''
	local src_prefix=''

	opts=$(pmodules::get_options -o h -l dst: -l delete -l help -- "$@")
	if [[ $? != 0 ]]; then
		subcommand_help_sync
		exit 1
	fi
	eval set --  "${opts}"
	while (($# > 0)); do
		case $1 in
			--dst )
				dst_prefix="$2"
				shift
				;;
			--delete )
				delete=true
				;;
			-- )
				:
				;;
			-* | -h | --help )
				echo "$1: illegal option" 1>&2
				subcommand_help_init
				exit 1
				;;
			* )
				[[ -n "${src_prefix}" ]] && \
				        std::die 1 "Error: Only one source is allowed!"
				src_prefix="$1"
				;;
		esac
		shift
	done
	unset -v opts

	if [[ -z "${dst_prefix}" ]]; then
		dst_prefix="${PMODULES_ROOT}"
	fi
	(
		PMODULES_ROOT="${dst_prefix}" pmodules::check_env || \
		        std::die 1 "Error: invalid destination modules environment!"
	) || std::die 1 "Giving up..."
	
	: ${src_prefix:=${PMODULES_INSTALL_SOURCE}} 
	if [[ -z "${src_prefix}" ]]; then
            std::die 1 "Error: no source module environment was specified!"
        fi
	(
		PMODULES_ROOT="${src_prefix}" pmodules::check_env || \
		    std::die 1 "Error: invalid source modules environment!"
	) || std::die 1 "Giving up..."
	[[ "$( cd "$src_prefix"; pwd -P )" == "$( cd "$dst_prefix"; pwd -P )" ]] && \
	    std::die 1 "Error: source and destination are equal!"
	local modbin=${PMODULES_HOME#"${PMODULES_ROOT}/"}/bin/modulecmd.tcl
	local file_type_src=$( file -b "${src_prefix}/${modbin}" 2>&1 || echo err1 )
	local file_type_dst=$( file -b "${dst_prefix}/${modbin}" 2>&1 || echo err2 )
	[[ "${file_type_src}" == "${file_type_dst}" ]] || \
	    std::die 1 "Error: The file signatures in the source and destination installation do not match!"
	unset -v file_type_src file_type_dst
	local dialog_script="${PMODULES_HOME}/bin/dialog.bash"
	[[ -r "$dialog_script" ]] || \
		std::die 1 "Error: Unable to find dialog script of installation $dialog_script";

	DIALOG_LIB=1                # use dialog script as a library
	source "$dialog_script"     # dialog functions

	# Redefine module_out to append modules to the selected_modules variable
        local -a selected_modules
	module_out() {
		local -a args=(${modlist[$1]})
		local path=""
		IFS=/
		[[ -n "${args[3]}" ]] && path="/${args[*]:3}"
		unset IFS
		selected_modules+=( "${args[2]}${path}/${args[0]}" )
	}

	module_picker "${dst_prefix}" "${src_prefix}" || {
		# this calls module_out for each selected module,
		#filling up the selected_modules array
		echo "Abort!"
		exit 1
	}

	local -a destination_modules=( $(cd "${dst_prefix}/${PMODULES_MODULEFILES_DIR}"; find -L . -type f | while read f; do n=${f##*/}; [[ "${n:0:1}" == "." ]] || echo ${f#./}; done) )

	# redefine set difference, the version in dialog.bash only handles integers
	set_difference() {  #  $1 \ $2
		local -a operand1=($1)
		local -a operand2=($2)
		local -A members
		local elem
		for elem in "${operand1[@]}"; do
			members[$elem]=1
		done
		for elem in "${operand2[@]}"; do
			unset members[$elem]
		done
		echo ${!members[@]}
	}

	if [[ "$delete" == "true" ]]; then
		local -a modules_delete=( $(set_difference "${destination_modules[*]}" "${selected_modules[*]}") )
		for m in "${modules_delete[@]}"; do
                        echo "Deleting module $m ..."
			delete_module "$m" "$dst_prefix"
		done
		unset modules_delete
	fi

	local -a modules_copy=( $(set_difference "${selected_modules[*]}" "${destination_modules[*]}") )
	if [[ -n $modules_copy ]]; then
		echo "Syncing configuration ..."
		sync_config "$src_prefix" "$dst_prefix" || \
		        std::die 1 "Error: syncing the configuration failed"
        fi
        for m in "${modules_copy[@]}"; do
                echo "Copying module $m ..."
		sync_module "$m" "$src_prefix" "$dst_prefix" || \
		        std::die 1 "Error: syncing of module $m failed!"
        done
	unset modules_copy
}

while (($# > 0)); do
	case $1 in
		-h | -H | -\? | --help | -help )
			usage
			exit 1
			;;
		-V | --version )
			print_version
			exit 1
			;;
		-f | --force )
			force='yes'
			;;
		--dry-run )
			dry_run='yes'
			DRY='echo'
			;;
		-* )
			echo "$1: unknown switch.\n" 1>&2
			exit 1
			;;
		init|install|sync|help )
			subcommand="subcommand_$1"
			shift
			sargs=( $* )
			shift $#
			;;
		* )
			echo "$1: unknown sub-command" 1>&2
			exit 1
	esac
	shift || :
done

if [[ -z ${subcommand} ]]; then
        usage
	exit 1
fi
[[ -z "${PMODULES_ROOT}" ]] && \
        std::die 1 "Error: No current module environment is configured!"
$subcommand "${sargs[@]}"

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# mode: sh
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# tab-width: 8
# End: