#!/usr/bin/env bash
# Copyright 2026 Hee-Suk Kim <hskim@dilluti0n.com>
# SPDX-License-Identifier: GPL-3.0-only

set -euo pipefail

. lib.bash

usage() {
    cat <<EOF
usage: ${NAME} [-h] <name> [<chain-ish>]
       ${NAME} -d <name>
       ${NAME} -l

Save <chain-ish> as <name> (default: HEAD)
  -d    Delete <name>
  -l    List saved names
  -h    Show this help
EOF
}

delete= list=
while getopts hdl o; do
    case "$o" in
        h) usage; exit 0 ;;
        d) delete=1 ;;
        l) list=1 ;;
        *) usage >&2; exit 1 ;;
    esac
done
shift $((OPTIND - 1))

[[ -z $delete || -z $list ]] || {
    echo fatal: -d and -l cannot be used together >&2
    usage
    exit 1
}

if [[ -n $list ]]; then
    # TODO: add pattern matching like git branch -l [<pattern>]
    sib ls-refs refs/conv/ | awk '{ sub(/^refs\/conv\//, "", $1); print $1 }'
    exit
fi

if [[ -n $delete ]]; then
    [[ $# -eq 1 ]] || {
        usage >&2
        exit 1
    }
else
    [[ $# -ge 1 && $# -le 2 ]] || {
        usage >&2
        exit 1
    }
fi

name="$1"
ref="refs/conv/$name"

sib git check-ref-format "$ref" || die "invalid name: $name"

if [[ -n $delete ]]; then
    sib update-ref --no-deref -d -m "save: delete $name" "$ref"
    exit
fi

#
# now save
#
target="${2:-HEAD}"
chain=$(sib rev-parse "$target" 2>/dev/null) || die "invalid chain: $target"
sib update-ref -m "save: $name" --no-deref "$ref" "$chain"

chain=$(sib git rev-parse --short $chain)
echo "Saved $chain to $name" >&2