#!/bin/bash
#
# Portainer Agent Deployment Script for Docker Swarm
# Usage: bash deploy_portainer_agent.sh
#

set -euo pipefail

log() { echo "[$(date '+%Y-%m-%d %H:%M:%S')] $*"; }

log "Checking Docker Swarm status..."
if ! docker info --format '{{.Swarm.LocalNodeState}}' | grep -q "active"; then
    log "ERROR: This node is not part of a Docker Swarm."
    exit 1
fi

if ! docker info --format '{{.Swarm.ControlAvailable}}' | grep -q "true"; then
    log "ERROR: This script must be run on a Swarm MANAGER node."
    exit 1
fi

log "Creating overlay network for Portainer Agent..."
if ! docker network ls | grep -q "portainer_agent_network"; then
    docker network create --driver overlay portainer_agent_network
else
    log "Network 'portainer_agent_network' already exists, skipping."
fi

log "Deploying Portainer Agent as a global Swarm service..."
if docker service ls | grep -q "portainer_agent"; then
    log "Agent service already exists. Updating to latest image..."
    docker service update --image portainer/agent:latest portainer_agent
else
    docker service create \
        --name portainer_agent \
        --network portainer_agent_network \
        --publish mode=host,target=9001,published=9001 \
        -e AGENT_CLUSTER_ADDR=tasks.portainer_agent \
        --mode global \
        --mount type=bind,src=//var/run/docker.sock,dst=/var/run/docker.sock \
        --mount type=bind,src=//var/lib/docker/volumes,dst=/var/lib/docker/volumes \
        --mount type=bind,src=//,dst=/host \
        portainer/agent:latest
fi

log "=== Portainer Agent Deployment Complete ==="
log "The agent is now deploying to all nodes in your Swarm."
log "To manage your Swarm:"
log "1. Open your Portainer Server UI."
log "2. Go to 'Environments' -> 'Add environment'."
log "3. Select 'Docker Swarm' and click 'Start Wizard'."
log "4. Choose 'Agent' and enter the Environment address: $(hostname -I | awk '{print $1}'):9001"
log "5. Click 'Connect'."