#!/bin/sh -u
#
# Try to file a file based on its name.
#	- Cameron Simpson <cs@zip.com.au> 13jan2005
#

trace=set-x

: ${TMPDIR:=/tmp}
: ${AUTOFILE_REMAPFILE:=$HOME/rc/remap}
: ${AUTOFILE_SAVEMAP:="remap \"\$AUTOFILE_REMAPFILE\""}

cmd=`basename "$0"`
usage="Usage: $cmd [-f mapfile] [filenames...]"

badopts=

[ "x$1" = "x-f" ] && { AUTOFILE_REMAPFILE=$2; shift; shift; }

[ $badopts ] && { echo "$usage" >&2; exit 2; }

[ $# = 0 ] && set -- -

remaptmp=$TMPDIR/$cmd-remap$$

for file
do
  if [ "x$file" = x- ]
  then cat
  else printf "%s\n" "$file"
  fi
done \
| $trace sh -c "$AUTOFILE_SAVEMAP" \
| \
{
  xit=0

  while read -r oldname \
  &&    read -r newname
  do
    [ -n "$newname" ] || continue
    [ "x$oldname" != "x$newname" ] || continue
    echo "$oldname -> $newname"

    if [ ! -f "$oldname" ]
    then
      echo "$cmd: not a regular file: $oldname" >&2
      xit=1
      continue
    fi

    case "$newname" in
      /* | ./* | ../* ) ;;
      *) newname=$HOME/$newname ;;
    esac
    case "$newname" in
      */)
	if [ -d "$newname/." ] || $trace mkdir -p "$newname"
	then
	  $trace mrg "$newname" "$oldname" || xit=1
	else
	  xit=1
	fi
	;;
      *)
	if [ -f "$newname" ]
	then
	  if cmp -s "$oldname" "$newname"
	  then
	    echo "$cmd: identical files ($oldname and $newname), removing $oldname"
	    $trace rm -- "$oldfile" || xit=1
	  else
	    echo "$cmd: differing file ($oldname and $newname), skipping $oldfile" >&2
	    xit=1
	  fi
	else
	  if [ -d "$newname/." ]
	  then
	    $trace mrg "$newname" "$oldname"
	  else
	    $trace mv -i -- "$oldfile" "$newfile" || xit=1
	  fi
	fi
	;;
    esac
  done

  exit $xit
}