#!/usr/bin/env bash
#
# Unregister an instance added by add-instance.sh: stops its PM2 process and
# drops it from scripts/instances.json. The database directory is left on
# disk — deleting credentials is a decision for a human with rm.
#
#   ./scripts/remove-instance.sh <N>
set -euo pipefail

ROOT="$(cd "$(dirname "$0")/.." && pwd)"
REGISTRY="$ROOT/scripts/instances.json"

info() { printf '  %s\n' "$1"; }
die()  { printf '  [X] %s\n' "$1" >&2; exit 1; }

[ $# -eq 1 ] || die "usage: $0 <N>"
N="$1"
case "$N" in (*[!0-9]*|'') die "N must be a number, got: $N" ;; esac
[ "$N" -ge 2 ] || die "instance 1 is the legacy install - remove it with pm2 delete autofirmer"
[ -f "$REGISTRY" ] || die "no scripts/instances.json - nothing to remove"

PM2_NAME="autofirmer-$N"

node - "$REGISTRY" "$PM2_NAME" <<'NODE'
const { readFileSync, writeFileSync } = require('node:fs');
const [, file, name] = process.argv;
const entries = JSON.parse(readFileSync(file, 'utf8'));
if (!entries.some((e) => e.name === name)) { console.error(`  [X] ${name} is not registered`); process.exit(1); }
writeFileSync(file, JSON.stringify(entries.filter((e) => e.name !== name), null, 4) + '\n');
console.log(`  registry: ${name} removed`);
NODE

pm2 delete "$PM2_NAME" >/dev/null 2>&1 || info "pm2: $PM2_NAME was not running"
pm2 save >/dev/null
info "pm2: $PM2_NAME deleted and process list saved"
info "database left at .data/instance-$N/ - delete by hand if you mean it"