#!/bin/bash -lx

set -eE -o pipefail
trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR

gen_args=()
do_snapshot=true
while [[ $1 ]]; do
    case $1 in
        -n) do_snapshot=false; shift ;;
        --) shift; break ;;
        -*) gen_args+=($1) ; shift ;;
        *) host=$1; shift ;;
    esac
done


# arch and debian don't play nice with unison.
# "connection lost" on unison-gtk, with bignum errs in term,
# and simply freezing on cli, all means compiled under
# different ocaml versions.
# I had the great realization that unison is a self contained
# binary with no special runtime dependencies.
# However, I got a gtk error running the ui version.
# todo: I should test pushing my unison version instead
# of pulling it.
/p/c/subdir_files/.unison/gen ${gen_args[@]}
if [[ ! $host ]]; then
    echo "$0: error: expected argument for hostname"
    exit 1
fi


# todo: this doesn't deal with if the host is running arch too

# note, without bash, it prints some crap about tty
# on an uncustomized jessie install.
scp /usr/bin/unison root@$host:/usr/local/bin

echo "$0: egen args ${gen_args[@]}"
if $do_snapshot; then
    unison-snapshot
    if ! ssh root@$host unison-snapshot; then
        if [[ ! ${gen_args[@]} ]]; then
            # gen_args are all about syncing with new systems where
            # we could expect the remote snapshot to not be available yet.
            echo "$0: error: failed remote unison-snapshot"
            exit 1
        fi
    fi
fi

f=unison-gtk
type -t $f &>/dev/null || f=unison-gtk2 # for arch
if s $f "$host"; then
    if [[ $host == frodo ]]; then
        # only send data to the machine i do full backups to
        p=/p/c/machine_specific/$HOSTNAME/.unison/
        s rsync -rlptgohi $p root@$host:$p
    fi
    p=/p/c/machine_specific/$host/.unison/
    s rsync -rlptgohvi root@$host:$p $p
fi