#!/bin/bash

# Run a command on the machine that is hosting the current working
# directory.  To make this work, assume local and remote have the same
# directory structure, and that the paths for NFS mounts have a
# particular canonical form (from "readlink -f")


# set -x

PWD=$(pwd)
ABS=$(readlink -f $PWD)

if [ -z "$1" ]; then
    COMMAND="cd $PWD; exec bash"
else
    # ssh command needs quoting
    COMMAND="cd $PWD; exec $(printf ' %q' "$@")"
fi
    

TTY=$(tty)
[ 0 == $? ] && TTY_ARGS=-t

exec_on_host() {
    exec ssh $TTY_ARGS -A $1 "$COMMAND"
}
path_field() {
    echo $ABS | cut -d/ -f$1
}

# Not a /net node
[ "net" != "$(path_field 2)" ] && exec "$@"

# /net node.  These are all of the form
#  2    3
# /net/$HOST
HOST=$(path_field 3)


# Some special cases that do not follow the 'vol' case below.
MAYBE_HOST=$(path_field 4)
case "$MAYBE_HOST" in
    panda|core)
        exec_on_host $MAYBE_HOST
        ;;
    vol)
        # Handle below
        ;;
    *)
        exec_on_host $HOST
        ;;
esac


# Two options here: either it is an LXC filesystem exported by the
# host, in which case we want to log into the LXC.  Otherwise, treat
# it as an exported directory on $HOST.

# LXC directories are of the form
#  2   3     4   5          6         7
# /net/$HOST/vol/$VOLUME_ID/$LXC_NAME/rootfs

[ "rootfs" != "$(path_field 7)" ] && exec_on_host $HOST

LXC_NAME=$(path_field 6)
exec_on_host "$LXC_NAME"