module Todoloo
  class ErrorHandler
    def initialize(kind)
      @handler = new_handler_proc(kind)
    end

    def call(error, original_exception: nil)
      # TODO(errors): Handle `original_exception`
      @handler.call(error)
    end

    private

    def new_handler_proc(kind)
      case kind
      when :raise
        proc { |e| raise e }
      when :stderr, :log, :trace
        new_handler($stderr)
      when String
        File.open(kind, "w")
      else
        if kind.respond_to?(:write)
          proc do |e|
            if e.is_a?(Error)
              kind.puts(e.message)
              kind.puts(e.backtrace) if e.backtrace && !e.backtrace.empty?
            else
              kind.puts(e)
            end
          end
        elsif kind.respond_to?(:call)
          kind
        else
          raise ArgumentError, "Unsupported type for ErrorHandler: #{kind}"
        end
      end
    end
  end
end