#!/usr/bin/env ruby
require "ostruct"
require "optparse"
require "json"

require_relative "lib/lxc"

def try_env(key)
  ENV[key] or abort("environment variable '#{key}' not set")
end

options = OpenStruct.new
options.container_name = try_env("LXC_NAME")
options.container_config = try_env("LXC_CONFIG_FILE")
options.rootfs = try_env("LXC_ROOTFS_PATH")
options.mounts = Hash.new { |hash,key| hash[key] = {} }

OptionParser.new do |opts|
  opts.banner = "Usage: create-lxc-config [options]"

  opts.on("-4", "--ipv4", "private Ipv4 subnet") do |v|
    options.ipv4 = v
  end
  opts.on("-6", "--ipv6", "public Ipv6 subnet") do |v|
    options.ipv6 = v
  end
  opts.on("--ula", String, "private unique local ipv6 subnet") do |v|
    options.ula = v
  end
  opts.on("--group GROUP", String, "set ansible group (default NONE)") do |group|
    options.group = group
  end
  opts.on("--mounts other_container,/src/dir,/dest/path", Array, "mount other container path") do |args|
    if args.size != 3
      abort "expect 3 arguments for --mounts got: #{args.size}: USAGE: other_container,/src/dir,/dest/path"
    end
    options.mounts[args[0]][args[1]] = args[2]
  end
  opts.on("--vars FILE", String, "set json file for ansible variables") do |vars|
    begin
      options.vars = JSON.load(File.open(vars))
      unless options.vars.is_a? Hash
        abort "vars: Should be a json object"
      end
    rescue SystemCallError => e
      abort "Failed to open '#{vars}': #{e.message}"
    rescue JSON::ParserError => e
      abort "Failed to parse ansible variables: #{e.message}"
    end
  end
end.parse!

registry = Lxc::Registry.new
container = Lxc::Container.new(registry.data,
                               name: options.container_name,
                               ipv4: options.ipv4,
                               ipv6: options.ipv6,
                               rootfs: options.rootfs,
                               ula: options.ula,
                               group: options.group,
                               vars: options.vars,
                               mounts: options.mounts)
container.write_config(options.container_config)
registry.save