#!/bin/bash
# Convert a MSYS path list to Windows-native format.
# Status is zero if successful, nonzero otherwise.

# Copyright (C) 2013-2014 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Take only the basename from the full pathname
me=${0//*\//}

usage="usage: ${me} PATHLIST"

help="$usage
  or:  ${me} OPTION

Convert a MSYS path list to Windows-native format.

PATHLIST should be a colon-separated list of MSYS paths, which will be
written to the standard output after performing these transformations:

1. Discard empty paths.
2. Replace: '\' with '/', '//' with '/' and ':' with ';'.
3. Translate each path to Windows-native format.

Relative paths or paths starting with '%emacs_dir%' will be passed
verbatim to the standard output.

Each non existing absolute path will be translated by looking for its
deepest existing directory, which will be translated and the remainder
appended.

Options:
  --help     display this help and exit

Report bugs to <bug-gnu-emacs@gnu.org>."

for arg
do
  case $arg in
    --help | --hel | --he | --h)
      exec echo "$help" ;;
    --)
      shift
      break ;;
    -*)
      echo "${me}: invalid option: $arg" >&2
      exit 1 ;;
    *)
      break ;;
  esac
done

[ $# -eq 1 ] || {
    echo "${me}: $usage" >&2
    exit 1
}

w32pathlist=""

# Put each MSYS path in one positional parameter and iterate through
# them
IFS=:
set -- $1

for p
do
    [ -z "$p" ] && continue

    if [ "${p:0:11}" = "%emacs_dir%" ]
    then
	w32p=$p
    elif [ "${p:0:1}" != "/" ]
    then
	w32p=$p
    elif [ -d "$p" ]
    then
	w32p=$(cd "$p" && pwd -W)
    else
	# Make some cleanup in the path and look for its deepest
	# existing directory

	p=${p//\\//}
	p=${p//\/\///}
	p=${p%/}

	p1=$p
	while :
	do
	    p1=${p1%/*}
	    [ -z "$p1" ] && p1="/" && break
	    [ -d "$p1" ] && break
	done

	# translate the existing part and append the rest
	w32p=$(cd "${p1}" && pwd -W)
	remainder=${p#$p1}
	w32p+=/${remainder#/}
    fi

    w32pathlist="${w32pathlist};${w32p}"

done

echo "${w32pathlist:1}"