#!/bin/bash
set -e

# Start libvirt and virtlogd services
echo "Starting libvirt and virtlogd daemons..."
/usr/sbin/libvirtd -d
/usr/sbin/virtlogd -d
sleep 2 # Give daemons a moment to start

# Change to the Vagrant project directory
cd /opt/win10 || exit

# Bring up the VM. This command is idempotent.
echo "Bringing up the VM..."
vagrant up

# Get the VM IP address using virsh
echo "Fetching VM IP address..."
DOMAIN_NAME="win10_default"

# It can take a while for the guest agent to report the IP address.
# We will retry a few times.
VM_IP=""
for i in {1..12}; do # Retry for 2 minutes (12 * 10s)
    # The output of domifaddr can be multiline, we are interested in ipv4
    # The output looks like:
    # Name       MAC address          Protocol     Address
    # -------------------------------------------------------------------------------
    # vnet1      52:54:00:ab:cd:ef    ipv4         192.168.121.44/24
    VM_IP=$(virsh domifaddr "$DOMAIN_NAME" 2>/dev/null | grep ipv4 | awk '{print $4}' | cut -d'/' -f1)
    if [ -n "$VM_IP" ]; then
        echo "VM IP Address found: $VM_IP"
        break
    fi
    echo "Waiting for VM to get an IP address... (attempt $i/12)"
    sleep 10
done

if [ -z "$VM_IP" ]; then
    echo "Fatal: Failed to get VM IP address after multiple retries."
    exit 1
fi

echo "Windows VM IP Address: $VM_IP"

# On the Docker HOST, add a rule to the DOCKER-USER chain to allow
# incoming RDP traffic to be forwarded to the container.
# This is the correct way to allow traffic when the FORWARD policy is DROP.
echo "Allowing RDP forwarding on the Docker host..."
iptables -I DOCKER-USER -p tcp --dport 33890 -j ACCEPT

# Inside the container, configure iptables for RDP port forwarding to the VM
echo "Configuring iptables for RDP..."
iptables -t nat -A PREROUTING -p tcp --dport 3389 -j DNAT --to-destination "$VM_IP":3389
iptables -t nat -A POSTROUTING -j MASQUERADE

echo "Port forwarding rule added."
echo "RDP connections to this container on port 3389 will be forwarded to the Windows VM."

# Keep the container running
echo "Container is running. Use 'docker exec' to access it."
tail -f /dev/null