#!/bin/bash

prefix=/usr/local
texmf_prefix=

usage() {
	cat <<EOF
usage: $(basename "$0") [options]
OPTIONS:
  --update		use PREFIX and TDS from a previous (existing) installation
  --no-update		do no use PREFIX and TDS from a previous (existing) installation
  --prefix PREFIX       use PREFIX as prefix path for installation
  --texmf-prefix TDS    configure LaTeX-Make to be installed into the
                        TeX Directory Standard 'TDS'

EOF
}

error() {
	echo 1>&2 "Error: $1"
	echo 1>&2
	usage 1>&2
	exit 1
}

cleanup-path() { #1 path
	local dir="$1"
	local motif rep dir2
	if [ -z "$dir" ]; then
		return;
	fi
	dir="$dir/"
	motif="//"
	rep="/"
	dir2="${dir/$motif/$rep}"
	while test "$dir2" != "$dir"; do
		dir="$dir2"
		dir2=${dir/$motif/$rep}
	done
	motif="/./"
	rep="/"
	dir2="${dir/$motif/$rep}"
	while test "$dir2" != "$dir"; do
		dir="$dir2"
		dir2=${dir/$motif/$rep}
	done
	dir2="$(echo "$dir" | sed -E -e 's,[^/]+/\.\./,,')"
	while test "$dir2" != "$dir"; do
		dir="$dir2"
		dir2="$(echo "$dir" | sed -E -e 's,[^/]+/\.\./,,')"
	done
	dir="${dir%/}"
	echo "$dir"
}

getopt -T >/dev/null 2>&1
if [ $? == 4 ]; then
	TMP="$(getopt --shell bash --options h \
		--name "$(basename "$0")" \
		--longoptions help,prefix:,texmf-prefix:,update,no-update \
		-- "$@")"
	if [ $? != 0 ]; then
		usage 1>&2
		exit 1
	fi
	eval set -- "$TMP"
fi

cur_prefix="$(make --no-print-directory --quiet -f detect-current-prefix.mk)"
TDS_current="$(kpsewhich -format texmfscripts LaTeX.mk | sed -e 's,/scripts/latex-make/LaTeX.mk$,,p;d')"
TDS_current="$(cleanup-path "$TDS_current")"

SETUP=

update() {
	SETUP=1
	if [ -n "$cur_prefix" ]; then
		prefix="$cur_prefix"
	fi
	if [ -n "$TDS_current" ]; then
		texmf_prefix="$TDS_current"
	fi
}

while [ $# != 0 ]; do
	case "$1" in
	--prefix=*) prefix="${1#--prefix=}" ;;
	--prefix) prefix="$2" ; shift;;
	--texmf-prefix=*) texmf_prefix="${1#--texmf-prefix=}" ;;
	--texmf-prefix) texmf_prefix="$2" ; shift;;
	--update) update;;
	--no-update) ;;
	--) shift; break ;;
	--help|-h) usage ; exit 0 ;;
	-*) error "Unknown option '$1'" ;;
	*) error "Invalid argument '$1'" ;;
	esac
	shift
	SETUP=1
done

if [ $# != 0 ]; then
	error "Invalid argument '$1'"
fi

if [ "$(uname -s)" != Linux -a -z "$SETUP" ]; then
	update
fi

find-default-TDS() {
	local dir
	local TDS_default=
	local TDS_default_fb=
	for dir in "$@"; do
		case "$dir" in
		*-local)
			if [ -z "$TDS_default" ]; then
				TDS_default="$dir"
			else
				if [ "$(echo "$dir" | wc -c)" -lt "$(echo "$TDS_default" | wc -c)" ]; then
					TDS_default="$dir"
				fi
			fi ;;
		*)
			if [ -z "$TDS_default_fb" ]; then
				TDS_default_fb="$dir"
			else
				if [ "$(echo "$dir" | wc -c)" -lt "$(echo "$TDS_default_fb" | wc -c)" ]; then
					TDS_default_fb="$dir"
				fi
			fi ;;
		esac
	done
	if [ -z "$TDS_default" ]; then
		TDS_default="$TDS_default_fb"
	fi
	echo "$TDS_default"
}

print-TDS() { # 1:starttoken
	declare -a loc
	declare -a home
	declare -a mid
	declare -a end
	declare -a all
	declare -a defs1
	declare -a defs2
	
	while read dir; do
		dir="$(cleanup-path "$dir/")"
		case "$dir" in
		"") ;;
		*"/."*) end=("${end[@]}" "$dir");;
		*"/local/"*|*"/opt/"*) loc=("${loc[@]}" "$dir");;
		*"/etc/"*) end=("${end[@]}" "$dir");;
		*"/var/"*) end=("${end[@]}" "$dir");;
		"${HOME}"*) home=("${home[@]}" "$dir");;
		*) mid=("${mid[@]}" "$dir");;
		esac
	done < <(kpsepath tex \
		| tr ':' '\n' \
		| sed -e 's/^!!//' -e 's,/*$,,' \
		| sed -e 's,/tex$,,p;d')
	
	trie() {
		local -a var
		eval 'var=( "${'"$1"'[@]}" )'
		for d in "${var[@]}"; do
			echo $d
		done | sort
	}
	
	OLD_IFS="$IFS"
	IFS="
	"
	all=( $(trie loc) $(trie mid) $(trie home) $(trie end) )
	defs1=( $(trie loc) )
	defs2=( $(trie mid) )
	IFS="$OLD_IFS"
	
	TDS_default="$(find-default-TDS "${defs1[@]}")"
	if [ -z "$TDS_default" ]; then
		TDS_default="$(find-default-TDS "${defs2[@]}")"
	fi
	if [ -z "$TDS_default" ]; then
		TDS_default="${texmf_prefix:-$prefix/share/texmf}"
	fi
	if [ -z "$texmf_prefix" ]; then
		texmf_prefix="$TDS_default"
	fi
	local rflag uflag cflag dflag aflag pdir
	local cur="$(cleanup-path "$texmf_prefix")"
	for dir in "${all[@]}" // ; do
		rflag=""
		uflag=""
		cflag=""
		dflag=""
		aflag=""
		if [ "$dir" == '//' ]; then
			if [ "$cur" == '//' ]; then
				continue
			fi
			dir="$cur"
		fi
		if [ "$dir" == "$TDS_default" ]; then
			dflag="*"
		fi
		if [ "$dir" == "$cur" ]; then
			aflag="@"
			cur='//'
		fi
		if [ "$dir" == "$TDS_current" ]; then
			cflag="+"
		fi
		if [ -e "$dir" ]; then
			pdir="$dir"
		else
			uflag="U"
			pdir="$(dirname "$dir")"
			while [ ! -d "$pdir" ]; do
				pdir="$(dirname "$pdir")"
			done
		fi
		if [ ! -w "$pdir" ]; then
			rflag="R"
		fi
		printf "%s[%1s%1s%1s%1s%1s] %s\n" "$1" "$aflag" "$dflag" "$cflag" "$rflag" "$uflag" "$dir"
	done 
	echo "### Current configuration" > config.mk
	echo "prefix=$prefix" >> config.mk
	echo "texmf_prefix=$texmf_prefix" >> config.mk
}

cat <<EOF
When installing LaTeX-Make, two paths must be chosen:
* prefix:
  The 'LaTeX.mk' file will be installed into \${prefix}/include. If you use a
  directory where your GNU-Make look for included files, you will be able to
  just put 'include LaTeX.mk' into your Makfiles.
    By default, LaTeX-Make use the '/usr/local' prefix, so 'LaTeX.mk' will
  be installed into '/usr/local/include'.
EOF
if [ -n "$cur_prefix" ]; then
	echo "    Currently, (an old version of) LaTeX-Make seems to be already installed"
	echo "  into '$cur_prefix'"
fi
cat <<EOF

* texmf_prefix:
  This is the base TeX tree (TeX Directory Structure) in which all LaTeX files
  will be installed. By default, this is '\${prefix}/share/texmf' but a list
  of such directories configurated on this system is provided below.
  One of them should probably be used.

Valid texmf_prefix values on this system:
=========================================
EOF
print-TDS "  "
cat <<EOF

Flags meaning:
  @: current configuration
  *: default auto choice (not always the best one...)
  +: current installation (if an old installation is detected)
  R: read-only TDS. Use 'sudo' for 'make install' if choosen
  U: unexistant but configurated TDS, will be created if choosen

You can now run:
================
    make
    make check #optional
    [sudo] make install

    or you can re-run this script to change the prefix and/or the texmf_prefix

EOF
echo "***************************"
while read l ; do
	echo "* $l";
done < config.mk
echo "***************************"
echo