#!/usr/bin/env nux-runner

### # nuxfs - Filesystem layout manager
###
### *nuxfs* command  uses file structure definition present in *.nuxfs* file
### to understand intented state of directory / filesystem of user.
###
### This definition is not only used to create filesystem hierarchy, checkout
### git repositories but also to verify state of filesystem afterwards.
###
### ## Example of .nuxfs file in home directory
###
###   *dir* github
###     *git* nux-env https://github.com/tonydamage/nux-env.git
###     *git* bats https://github.com/sstephenson/bats.git
###   *enddir*
###   *link* .bashrc github/nux-env/bashrc
###
### This *.nuxfs* file describes simple home structure. If we execute
### **nuxfs apply** command, it will performs filesystem changes in order to
### recreate structure described in *.nuxfs* file. In case of example it is
### equivalent of executing:
###     mkdir -p github
###     git clone https://github.com/tonydamage/nux-env.git github/nux-env
###     git clone https://github.com/sstephenson/bats.git
###     ln -s github/nux-env/bashrc .bashrc
###

local WORKDIR=$(pwd)
local TEMPLATE_DIR=$NUX_ENV_DIR/templates
local SUFFIX=".nuxfs"
local TEMPLATE_FILTER="*$SUFFIX"

nux.use nux.dsl
nux.use nuxfs


GIT_BIN=$(which git)

##   check   Verifies that directories and files matches the specification
##           in *.nuxfs* definition
##
task.check() {
  nuxfs.dsl.process "$@";
}

task.describe() {
  nuxfs.dsl.process "$@";
}

##   apply   Creates missing files as specified in *.nuxfs* definition.
##           **DOES NOT MODIFY** existing files breaking specification.
##
task.apply() {
  nuxfs.dsl.process "$@";
}

##   fix     Performs apply and tries to fix warnings and errors and files as
##           specified in nuxfs definition. This operation **DOES MODIFY**
##           existing files.
##
task.fix() {
  nuxfs.dsl.process "$@";
}

##   help.dsl   Displays help for **nuxfs DSL language**
##
task.help.dsl() {
  nux.help.comment "$NUX_INC_DIR/dsl/nuxfs.dsl"
}

nuxfs.dsl.process() {
  WORKDIR=$(pwd);
  TARGET=$1;
	if [ -n "$TARGET" ]; then
		TARGET=$TARGET
  else
		TARGET=$(pwd);
	fi;

  TARGET=$(realpath -Lms "$TARGET")
  nux.log debug Target: $TARGET

	NUXFS_DEF=$(nuxfs.closest $SUFFIX "$TARGET");
#
	if [ "$NUXFS_DEF" = "" ]; then
		nuxfs.error $(pwd) "No nuxfs configuration found."
		exit 1;
	fi
	NUXFS_DEF_DIR=$(dirname $NUXFS_DEF);
	TARGET_RELATIVE=$(realpath -ms "$TARGET" --relative-to "$NUXFS_DEF_DIR")
	TARGET_ABSOLUTE=$(realpath -ms "$TARGET")
  if [ "$TARGET_RELATIVE" != . ]; then
     if [[ $$TARGET_RELATIVE != ./* ]]; then
      TARGET_RELATIVE="./$TARGET_RELATIVE"
    fi
    nux.dsl.only.subtree "$TARGET_RELATIVE"
  fi

  nux.log debug nuxfs definition: $NC_White$NUXFS_DEF$NC_No
  nux.log debug $NC_White"target directory:$Nc_No"
  nux.log debug "   relative to def:" $NC_White$TARGET_RELATIVE$NC_No
  nux.log debug "   absolute path:  " $NC_White$TARGET_ABSOLUTE$NC_No

  if test -e "$NUXFS_DEF"; then
  #    #NUXFS_TARGET_FOUND=0;
    nux.dsl.execute "$NUX_INC_DIR/dsl/nuxfs.$TASK" "$NUXFS_DEF";

  #    #if [ $NUXFS_TARGET_FOUND = 0 ]; then
  #    #  nuxfs.warning "$3" "Does not have definition in $DEF";
  #   fi
  else
    nuxfs.error "$NUXFS_DEF"  Definition file does not exists.
  fi
}

##   init    Initializes a directory using template
##
function task.init {
	if [ $# -eq 0 ]; then
		nux.log debug "No template specified. Creating empty $SUFFIX definition."
		touch .nuxfs
		return;
	fi
	local TEMPLATE=$1
	nux.log debug "User specified template is " $TEMPLATE
	if [ $(echo $TEMPLATE | grep -c "$SUFFIX\$") -eq 0 ]; then
		nux.log debug "Template is common template."
		TEMPLATE=$TEMPLATE_DIR/$TEMPLATE$SUFFIX
		if [ ! -e $TEMPLATE ]; then
			echo -n "Template '$1' does not exists. "
			nuxfs.template.list
			return;
		fi;

	fi;
	nux.log debug "Using '$TEMPLATE' to initialize."
	if [ ! -e $TEMPLATE ]; then
		echo "nuxfs template $1 does not exists."
		return;
	fi;
  local template_relative=$(realpath -Lms $TEMPLATE --relative-to $(pwd))
	nux.log debug "Creating link $SUFFIX:  target is '$template_relative'";
	ln -s "$template_relative" "$SUFFIX"
	nux.log debug "Invoking create task."
	task.create
}

##   template - List available templates
##
function task.template {
	nux.log debug $NUX_ENV_DIR
	nuxfs.template.list
}

function task.info {
	nuxfs.initcfg;
	if [ -n "$NUXFS_DEF" ]; then
		MANAGED_RELATIVE=$(realpath $NUXFS_DEF_DIR --relative-to $(pwd));

		if [ "$MANAGED_RELATIVE" = . ]; then
			echo $(pwd) is nuxfs managed directory.
		else
			echo $(pwd) is child of nuxfs managed directory.
			echo Managed directory is $NUXFS_DEF_DIR.
		fi;
  else
		echo "$(pwd) is not managed by nuxfs";

	fi;
}

function nuxfs.dsl.capture.dir {
  local CDIR=$1;
	local LEVEL=$2;
	nux.log debug "Inspecting directory $CDIR";

	if [ -e "$RELATIVE/$SUFFIX" ]; then
		return;
	fi;

	pushd "$CDIR" > /dev/null;
	for file in ./* ; do
		nuxfs.dsl.capture.file "$file" ".";
	done;
	popd > /dev/null;
}

function nuxfs.dsl.capture.file {
	local file=$1;
	local pdir=$2;
	local RELATIVE=$(realpath -ms "$file" --relative-to "$pdir");
	local ADDARGS="";
	local TYPE="";
	nux.log debug "Inspecting $file , Relative path is $RELATIVE";
	if [ -h "$RELATIVE" ]; then
		TYPE="link";
		ADDARGS="\"$(readlink "$RELATIVE")\""
	elif [ -d "$RELATIVE" -a -d "$RELATIVE/.git" ]; then
		TYPE=git;
		pushd "$RELATIVE" > /dev/null;
		ADDARGS="\"$($GIT_BIN remote get-url origin)\""
		popd  > /dev/null;
	elif [ -d "$RELATIVE" ]; then
		TYPE="dir";
	fi;

	if [ "$TYPE" ]; then
		echo  -e "${LEVEL}$TYPE \"$RELATIVE\" $ADDARGS";
	fi;

	if [ "$TYPE" = "dir" -a "$LEVEL" != "      " ]; then
		nuxfs.dsl.capture.dir "$RELATIVE" "${LEVEL}  "
		echo "${LEVEL}enddir";
	fi;
}

##  capture - Captures current directory to nuxfs syntax
function task.capture {
	if [ $# -eq 0 ]; then
		nuxfs.dsl.capture.dir .

	else
		for file in "$@" ; do
			nuxfs.dsl.capture.file "$file" .;
		done;
	fi

}

function nuxfs.template.list {
	echo "Available templates:";
	pushd $TEMPLATE_DIR > /dev/null;
  for i in $TEMPLATE_FILTER; do
		local TEMPLATE_ID=$(basename $i $SUFFIX)
		echo -n "  $TEMPLATE_ID - " ;
		grep -m1 "^name " $i | sed -e "s/name *//"
		echo
	done;
	popd > /dev/null;
}


function nuxfs.initcfg {

	WORKDIR=$1;
	if [ -n "$WORKDIR" ]; then
		WORKDIR=$WORKDIR
  else
		WORKDIR=$(pwd);
	fi;

	nux.log debug Target: $WORKDIR

	NUXFS_DEF=$(nuxfs.closest $SUFFIX "$WORKDIR");

	if [ "$NUXFS_DEF" = "" ]; then
		nuxfs.error $(pwd) "No nuxfs configuration found."
		return;
	fi;
	NUXFS_DEF_DIR=$(dirname $NUXFS_DEF);
	WORKDIR_RELATIVE=$(realpath -ms "$WORKDIR" --relative-to "$NUXFS_DEF_DIR")
	WORKDIR_ABSOLUTE=$(realpath -ms "$WORKDIR")

}