#!/bin/bash

# Exit on any error
set -e

# Check if running as root
if [ "$EUID" -ne 0 ]; then
    echo "Please run as root"
    exit 1
fi

# Default values
DOCKER_IMAGE="alpine:3.16.0"
CONTAINER_NAME="dockerimage"
TEMPLATE_NAME="alpine-3.16-docker_$(date +%Y%m%d)_amd64.tar.xz"

# Parse command line arguments
while getopts "i:n:t:" opt; do
    case $opt in
        i) DOCKER_IMAGE="$OPTARG" ;;
        n) CONTAINER_NAME="$OPTARG" ;;
        t) TEMPLATE_NAME="$OPTARG" ;;
        ?) echo "Usage: $0 [-i docker_image] [-n container_name] [-t template_name]" >&2; exit 1 ;;
    esac
done

echo "Installing required packages..."
apt update && apt -y install skopeo umoci jq

echo "Creating LXC container from Docker image..."
lxc-create "$CONTAINER_NAME" -t oci -- --url "docker://${DOCKER_IMAGE}"

echo "Updating network configuration..."
sed -i "s/lxcbr0/vmbr0/" "/var/lib/lxc/${CONTAINER_NAME}/config"

echo "Removing extra TTYs..."
sed -i '/.*tty[56]$/d' "/var/lib/lxc/${CONTAINER_NAME}/rootfs/etc/inittab"

echo "Configuring network interfaces..."
cat << EOF > "/var/lib/lxc/${CONTAINER_NAME}/rootfs/etc/network/interfaces"
auto eth0
iface eth0 inet dhcp
hostname \$(hostname)
EOF

echo "Adding required packages..."
WORLD="/var/lib/lxc/${CONTAINER_NAME}/rootfs/etc/apk/world"
for pkg in alpine-base alpine-baselayout alpine-keys apk-tools busybox doas libc-utils logrotate; do
    grep -q "^${pkg}$" "$WORLD" || echo "$pkg" >> "$WORLD"
done
LC_ALL=C sort "$WORLD" -o "$WORLD"

echo "Starting container and configuring services..."
lxc-start -f "/var/lib/lxc/${CONTAINER_NAME}/config" --name="$CONTAINER_NAME" --logfile ~/lxc.log --logpriority DEBUG

# Wait for container to start
sleep 5

# Configure networking and install packages
cat << 'EOF' | lxc-attach --name="$CONTAINER_NAME"
ifdown -a
ifup -a && apk add --root=/ --initdb $(cat /etc/apk/world)

rc-update --quiet add bootmisc boot
rc-update --quiet add hostname boot
rc-update --quiet add savecache shutdown
rc-update --quiet add killprocs shutdown
rc-update --quiet add syslog boot
rc-update --quiet add networking boot default
rc-update --quiet add crond default

reboot
EOF

# Wait for container to reboot
sleep 10

echo "Preparing template files..."
ROOTFS="/var/lib/lxc/${CONTAINER_NAME}/rootfs"

# Stop container
lxc-stop --name="$CONTAINER_NAME"

# Update template files
cat << EOF > "${ROOTFS}/etc/hosts"
127.0.1.1   LXC_NAME
127.0.0.1   localhost localhost.localdomain
::1         localhost localhost.localdomain
EOF

echo "LXC_NAME" > "${ROOTFS}/etc/hostname"

# Clean up files
echo -n > "${ROOTFS}/root/.ash_history"
rm -f "${ROOTFS}/var/log/messages"*
echo -n > "${ROOTFS}/var/log/messages"

# Clean /run directory
cd "${ROOTFS}/run/"
rm -rf ./*

echo "Creating template..."
TEMPLATEDIR="/var/lib/vz/template/cache"
tar -cJf "${TEMPLATEDIR}/${TEMPLATE_NAME}" -p --sparse -C "$ROOTFS" $(ls -A "$ROOTFS")

echo "Cleaning up..."
lxc-destroy "$CONTAINER_NAME"

echo "Template creation complete: ${TEMPLATE_NAME}"
echo "You can now create containers from this template using the Proxmox GUI or pct create command"