#!/bin/bash
set -euo pipefail

# Install Caddy web server on Debian/Ubuntu/Raspbian using the official
# Cloudsmith apt repository.
# Follows the official docs:
#   https://caddyserver.com/docs/install#debian-ubuntu-raspbian

if [ "$EUID" -ne 0 ]; then
  echo "Please run as root (sudo)." >&2
  exit 1
fi

. /etc/os-release

case "$ID" in
  debian|ubuntu|raspbian) ;;
  *)
    echo "Unsupported distribution: $ID (only Debian, Ubuntu and Raspbian are supported)." >&2
    exit 1
    ;;
esac

ARCH="$(dpkg --print-architecture)"
case "$ARCH" in
  amd64|arm64|armhf) ;;
  *)
    echo "Unsupported architecture: $ARCH" >&2
    exit 1
    ;;
esac

export DEBIAN_FRONTEND=noninteractive

echo "==> Installing prerequisites"
apt-get update
apt-get install -y debian-keyring debian-archive-keyring apt-transport-https curl

echo "==> Installing Caddy"
apt-get update
apt-get install -y caddy

echo "==> Creating site directories"
mkdir -p /etc/caddy/sites-available /etc/caddy/sites-enabled /var/log/caddy
if id caddy >/dev/null 2>&1; then
  chown -R caddy:caddy /var/log/caddy
fi

echo "==> Writing global config with distinguished logging"
cat > /etc/caddy/Caddyfile <<'EOF'
# Global options
{
	admin off

	# Distinguished logging:
	# - global log: process/error-level events for all sites
	# - per-site access logs: written by each site block in sites-enabled/
	log {
		output file /var/log/caddy/caddy.log
		format json
		level INFO
	}
}

# Load enabled sites (symlinks into sites-enabled/)
import /etc/caddy/sites-enabled/*.conf
EOF

echo "==> Writing default site config"
cat > /etc/caddy/sites-available/00-default.conf <<'EOF'
:80 {
	root * /usr/share/caddy
	encode gzip
	file_server

	# Per-site access log (distinguished from the global log)
	log {
		output file /var/log/caddy/default.access.log
		format json
		level INFO
	}
}
EOF

ln -sf /etc/caddy/sites-available/00-default.conf /etc/caddy/sites-enabled/00-default.conf

echo "==> Writing template site config"
cat > /etc/caddy/sites-available/example.com.conf <<'EOF'
# Template site config.
# To create a real site:
#   1. cp /etc/caddy/sites-available/example.com.conf /etc/caddy/sites-available/mysite.com.conf
#   2. Replace example.com, /var/www/example.com and the log path.
#   3. Enable it:
#        ln -s /etc/caddy/sites-available/mysite.com.conf /etc/caddy/sites-enabled/mysite.com.conf
#   4. Reload: systemctl reload caddy
#
# example.com {
# 	root * /var/www/example.com
# 	encode gzip
# 	file_server
#
# 	# Per-site access log (distinguished from the global log)
# 	log {
# 		output file /var/log/caddy/example.com.access.log
# 		format json
# 		level INFO
# 	}
# }
EOF

echo "==> Restarting Caddy with new config"
systemctl restart caddy

echo "Caddy installed. Service status: systemctl status caddy"
echo "Sites: /etc/caddy/sites-available (template: example.com.conf)"
echo "Enabled: /etc/caddy/sites-enabled"