#!/usr/bin/ruby

require 'rbvmomi'
require 'redis'
require 'yaml'

$:.unshift( File.dirname( __FILE__ ) )
require 'lib/require_relative'
require 'lib/vsphere_helper'

vsphere_helper = VsphereHelper.new

Dir.chdir( File.dirname( __FILE__ ) )

# Load the configuration file
config_file = File.expand_path( 'vmware-host-pooler.yaml' )

pools   = YAML.load_file( config_file )[:pools]
vsphere = YAML.load_file( config_file )[:vsphere]

# Connect to vSphere
$vim = RbVmomi::VIM.connect(
  :host     => vsphere['server'],
  :user     => vsphere['username'],
  :password => vsphere['password'],
  :ssl      => true,
  :insecure => true,
  :rev      => '5.1'
)

# Connect to Redis
$redis = Redis.new

# Update loop
loop do
  pools.each do |pool|
    total = 0

    # Locate the resource pool
    datacenter = $vim.serviceInstance.find_datacenter
    base = vsphere_helper.find_pool(pool['pool'])

    # Count the number of VMs and correlate Redis inventory
    inventory = {}
    base.vm.each do |vm|
      if ! $redis.sismember('vmware_host_pool-'+pool['name'], vm['name'])
        $redis.sadd('vmware_host_pool-'+pool['name'], vm['name'])
      end
      inventory[vm['name']] = 1
      total = total + 1
    end

    $redis.smembers('vmware_host_pool-'+pool['name']).each do |vm|
      if ! inventory[vm]
        $redis.srem('vmware_host_pool-'+pool['name'], vm)
      end
    end

    # Bring the pool up to the desired size
    if total < pool['size']

      # Provision VMs
      (1..(pool['size']-total)).each { |i|
        vm = {}

        if pool['template'] =~ /\//
          templatefolders = pool['template'].split('/')
          vm['template'] = templatefolders.pop
        end

        if templatefolders
          vm[vm['template']] = vsphere_helper.find_folder(templatefolders.join('/')).find(vm['template'])
        else
          raise "Please provide a full path to the template"
        end

        if vm['template'].length == 0
          raise "Unable to find template '#{h['template']}'!"
        end

        # Generate a randomized hostname
        o = [('a'..'z'),('0'..'9')].map{|r| r.to_a}.flatten
        vm['hostname'] = o[rand(25)]+(0...14).map{o[rand(o.length)]}.join

        # Put the VM in the specified folder and resource pool
        relocateSpec = RbVmomi::VIM.VirtualMachineRelocateSpec(
          :datastore    => vsphere_helper.find_datastore(pool['datastore']),
          :pool         => vsphere_helper.find_pool(pool['pool']),
          :diskMoveType => :moveChildMostDiskBacking
        )

        # Create a clone spec
        spec = RbVmomi::VIM.VirtualMachineCloneSpec(
          :location      => relocateSpec,
          :powerOn       => true,
          :template      => false
        )

        puts '[+] '+vm.inspect

        # Clone the VM
        vm[vm['template']].CloneVM_Task(
          :folder => vsphere_helper.find_folder(pool['folder']),
          :name => vm['hostname'],
          :spec => spec
        ).wait_for_completion

        # Add VM to Redis inventory
        $redis.sadd('vmware_host_pool-'+pool['name'], vm['hostname'])
      }
    end

    # ZZZzzz...
    sleep(5)
  end
end