module Hbc
  module Caskroom
    class << self
      module Compat
        def migrate_legacy_caskroom
          return if Hbc.caskroom.exist?

          legacy_caskroom = Pathname.new("/opt/homebrew-cask/Caskroom")
          return if Hbc.caskroom == legacy_caskroom
          return unless legacy_caskroom.exist?
          return if legacy_caskroom.symlink?

          ohai "Migrating Caskroom from #{legacy_caskroom} to #{Hbc.caskroom}."
          if Hbc.caskroom.parent.writable?
            FileUtils.mv legacy_caskroom, Hbc.caskroom
          else
            opoo "#{Hbc.caskroom.parent} is not writable, sudo is needed to move the Caskroom."
            SystemCommand.run("/bin/mv", args: [legacy_caskroom, Hbc.caskroom.parent], sudo: true)
          end

          ohai "Creating symlink from #{Hbc.caskroom} to #{legacy_caskroom}."
          if legacy_caskroom.parent.writable?
            FileUtils.ln_s Hbc.caskroom, legacy_caskroom
          else
            opoo "#{legacy_caskroom.parent} is not writable, sudo is needed to link the Caskroom."
            SystemCommand.run("/bin/ln", args: ["-s", Hbc.caskroom, legacy_caskroom], sudo: true)
          end
        end

        def migrate_caskroom_from_repo_to_prefix
          repo_caskroom = HOMEBREW_REPOSITORY.join("Caskroom")
          return if Hbc.caskroom.exist?
          return unless repo_caskroom.directory?

          ohai "Moving Caskroom from HOMEBREW_REPOSITORY to HOMEBREW_PREFIX"

          if Hbc.caskroom.parent.writable?
            FileUtils.mv repo_caskroom, Hbc.caskroom
          else
            opoo "#{Hbc.caskroom.parent} is not writable, sudo is needed to move the Caskroom."
            SystemCommand.run("/bin/mv", args: [repo_caskroom, Hbc.caskroom.parent], sudo: true)
          end
        end
      end

      prepend Compat
    end
  end
end