#!/usr/bin/env ruby
require 'json'
require 'net/http'
require 'rubygems'

class CLI
  def run
    puts 'Building latest' if latest?
    puts "Tags: #{ tags_for_embark_version.join(', ') }"

    command = ['docker', 'build', '.']
    tags_for_embark_version.each { |tag| command << "-t=statusim/embark:#{tag}" }

    system(command.join(' '))

    push_to_registry if ARGV.include?('--release')
  end

  private

  def push_to_registry
    tags_for_embark_version.each do |tag|
      command = ['docker', 'push', "statusim/embark:#{tag}"]
      system(command.join(' '))
    end
  end

  def embark_versions
    embark_versions ||= begin
                          package_info['time'].keys.map do |v|
                            Gem::Version.new(v) rescue nil
                          end.compact.select { |v| v < Gem::Version.new('7.0.0') }
                        end
  end

  def package_info
    package_info ||= begin
                       json = Net::HTTP.get('registry.npmjs.org', '/embark')
                       JSON.parse(json)
                     end
  end


  def embark_version
    embark_version ||= begin
                         dockerfile_path = File.expand_path('../../Dockerfile', __FILE__)
                         dockerfile = File.open(dockerfile_path, 'r').read
                         Gem::Version.new(dockerfile.match(/EMBARK_VERSION=([0-9.]*)/)[1])
                       end
  end

  def latest?
    package_info['dist-tags']['latest'] == embark_version.to_s
  end

  def tags_for_embark_version
    tags = []
    tags << 'latest' if latest?
    tags << embark_version

    # Version being X.Y.Z, figure out if we're the largest X.Y
    same_minor_versions = embark_versions.select { |ev| ev.segments[0..1] == embark_version.segments[0..1] }.sort
    tags << embark_version.segments[0..1].join('.') if embark_version == same_minor_versions.last

    # Version being X.Y.Z, figure out if we're the latest X
    same_major_versions = embark_versions.select { |ev| ev.segments[0] == embark_version.segments[0] }.sort
    tags << embark_version.segments[0].to_s if embark_version == same_major_versions.last

    tags
  end
end

CLI.new.run