#!/usr/bin/env bash
#
# Prune old snapshots from the restic repo in $RESTIC_REPOSITORY.
#
set -Eeuo pipefail

if [[ -z "${RESTIC_REPOSITORY:-}" ]]; then
    echo '❌ RESTIC_REPOSITORY is not set' >&2
    exit 1
fi

ensure_repository_ready() {
    if ! restic cat config >/dev/null 2>&1; then
        printf '❌ No restic repository found at "%s"\n' "$RESTIC_REPOSITORY" >&2
        exit 1
    fi
}

forget_old_snapshots() {
    printf '🧠 Forgetting extra backups in "%s"\n' "$RESTIC_REPOSITORY"
    restic unlock
    restic forget \
        --retry-lock 3h \
        --keep-within-daily 7d \
        --keep-within-weekly 1m \
        --keep-within-monthly 1y \
        --keep-within-yearly 100y \
        --prune
}

ensure_repository_ready
forget_old_snapshots