#!/usr/bin/env ruby

require "bundler/setup"
require "github_api"
require "pathname"
require "json"

class Release
  NAME = "Trix"
  REPO = "trix"
  OWNER = "basecamp"

  def perform
    confirm_version
    check_github_release
    check_npm

    build
    update_package_json
    update_license
    commit_changes
    create_release
    npm_publish
  end

  def version
    @version ||= Pathname.new("src/trix/VERSION").read.chomp
  end

  def confirm_version
    confirm("Release #{NAME} #{version}?") || abort
  end

  def build
    puts "Building…"
    system("rm -rf tmp/ && bin/blade build") || abort("Build failed")
  end

  def update_package_json
    puts "Updating package.json…"

    pathname = Pathname.new("package.json")
    data = JSON.parse(pathname.read)
    data["version"] = version
    pathname.write(JSON.pretty_generate(data) + "\n")
  end

  def update_license
    puts "Updating LICENSE…"

    pathname = Pathname.new("LICENSE")
    contents = pathname.read
    year = Time.now.year

    (year - 1).downto(year - 3) do |previous_year|
      pattern = / #{previous_year} /
      if contents =~ pattern
        pathname.write(contents.gsub!(pattern, " #{year} "))
        break
      end
    end
  end

  def commit_changes
    puts `git status #{pathspecs.join(' ')}`

    if confirm "Commit changes?"
      abort("Failed to commit") unless \
        system("git add #{pathspecs.join(' ')}") &&
        system("git commit -m '#{NAME} #{version}'") &&
        system("git push") &&
        system("git tag #{version}") &&
        system("git push --tags")
    else
      abort
    end
  end

  def create_release
    puts "Creating release…"
    release = github.repos.releases.create(OWNER, REPO, tag_name: version)

    puts "Uploading dist files for release…"
    dist_pathnames.each do |pathname|
      github.repos.releases.assets.upload OWNER, REPO, release.id, pathname.to_s, name: pathname.basename.to_s, content_type: content_type(pathname)
    end
  end

  def pathspecs
    %w( dist/ src/ package.json LICENSE )
  end

  def dist_pathnames
    Pathname.new("dist").children
  end

  def content_type(pathname)
    case pathname.extname
    when ".js"  then "application/javascript"
    when ".css" then "text/css"
    end
  end

  def check_github_release
    releases = github.repos.releases.list(OWNER, REPO)
    if release = releases.detect { |release| release.tag_name == version }
      abort "Already released #{version}: #{release.html_url}"
    end
  end

  def github
    @github ||= begin
      username = `git config --global --get github.user`.chomp
      password = `git config --global --get github.token`.chomp

      if username.nil? || username == "" || password.nil? || password == ""
        abort "Must set github.user and github.token in your global gitconfig"
      end

      Github.new basic_auth: "#{username}:#{password}"
    end
  end

  def check_npm
    system("npm whoami") || abort("Must be logged in to npm" )
  end

  def npm_publish
    puts "Publishing to npm…"
    system("npm publish") || abort("npm publish failed")
  end

  def confirm(question)
    print "#{question} (y/n) "
    gets.chomp.downcase == "y"
  end
end

Release.new.perform