voltrb/volt

# The BaseBinding class is the base for all bindings.  It takes
# 4 arguments that should be passed up from the children (via super)
#
# 1. page - this class instance should provide:
#            - a #templates methods that returns a hash for templates
#            - an #events methods that returns an instance of DocumentEvents
# 2. target -  an DomTarget or AttributeTarget
# 3. context - the context object the binding will be evaluated in
# 4. binding_name - the id for the comment (or id for attributes) where the
#                   binding will be inserted.
module Volt
  class BaseBinding
    attr_accessor :target, :context, :binding_name, :volt_app

    def initialize(volt_app, target, context, binding_name)
      @volt_app     = volt_app
      @target       = target
      @context      = context
      @binding_name = binding_name

      @@binding_number ||= 10_000
    end

    def browser
      @volt_app.browser
    end

    def dom_section
      @dom_section ||= target.dom_section(@binding_name)
    end

    def remove
      @dom_section.remove if @dom_section

      # Clear any references
      @target      = nil
      @context     = nil
      @dom_section = nil
    end

    def remove_anchors
      @dom_section.remove_anchors if @dom_section
    end

    # log out a message about a failed computation or Promise.
    def getter_fail(error)
      message = "#{self.class.to_s} Error: #{error.inspect}"

      if RUBY_PLATFORM == 'opal'
        if `#{@getter}`
          message += "\n" + `#{@getter}.toString()`
        end
      else
        if error.respond_to?(:backtrace)
          message += "\n" + error.backtrace.join("\n")
        end
      end

      Volt.logger.error(message)
    end
  end
end