#!/usr/bin/env bash
# One-time droplet setup. Run ON the droplet as root:
#   bash setup-droplet.sh 'hands.kestrelsnest.social, waving-hands.<droplet-ip>.sslip.io'
# The argument is the Caddy site address line: one name, or several
# separated by commas. Every name must already resolve to this droplet.
# Waving Hands is a static site: Caddy serves the built files and terminates
# TLS. There is no application process, so nothing but Caddy and rsync is
# installed.
set -euo pipefail
HOST="${1:?usage: setup-droplet.sh <hostname>}"

apt-get update -q
apt-get install -qy curl rsync

# Caddy (auto-HTTPS)
apt-get install -qy debian-keyring debian-archive-keyring apt-transport-https
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/gpg.key' \
  | gpg --dearmor -o /usr/share/keyrings/caddy-stable-archive-keyring.gpg
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/debian.deb.txt' \
  | tee /etc/apt/sources.list.d/caddy-stable.list
apt-get update -q && apt-get install -qy caddy

# Site directory, readable by Caddy.
mkdir -p /opt/waving-hands/build
chown -R root:caddy /opt/waving-hands
chmod -R g+rX /opt/waving-hands

# Caddy vhost: auto-TLS, security headers, static files. SvelteKit writes
# each route as <route>.html, so /rules is tried as /rules.html before
# falling back to the app shell. Hashed assets under _app/immutable are
# cached for a year; everything else is revalidated so a deploy shows up
# on the next load.
cat > /etc/caddy/Caddyfile <<CADDY
$HOST

root * /opt/waving-hands/build
encode gzip zstd

header {
	Strict-Transport-Security "max-age=31536000"
	X-Content-Type-Options "nosniff"
	X-Frame-Options "DENY"
	Referrer-Policy "no-referrer"
}
header /_app/immutable/* Cache-Control "public, max-age=31536000, immutable"
header /index.html Cache-Control "no-cache"

log {
	output file /var/lib/caddy/access.log {
		roll_size 10MiB
		roll_keep 30
	}
}

try_files {path} {path}.html /index.html
file_server
CADDY
systemctl reload caddy

# Firewall: ssh + web only.
ufw allow OpenSSH
ufw allow 80/tcp
ufw allow 443/tcp
ufw --force enable

echo "droplet ready: now run deploy/deploy.sh <ip> from your machine"