# frozen_string_literal: true

module Nanoc
  module Core
    # @api private
    class DependencyTracker
      include Nanoc::Core::ContractsSupport

      C_OBJ =
        C::Or[
          Nanoc::Core::Item,
          Nanoc::Core::Layout,
          Nanoc::Core::Configuration,
          Nanoc::Core::IdentifiableCollection
        ]

      C_RAW_CONTENT =
        C::Or[
          C::IterOf[C::Or[String, Regexp]],
          C::Bool
        ]

      C_ATTR =
        C::Or[
          C::IterOf[Symbol],
          C::Bool
        ]

      C_ARGS =
        C::KeywordArgs[
          raw_content: C::Optional[C_RAW_CONTENT],
          attributes: C::Optional[C_ATTR],
          compiled_content: C::Optional[C::Bool],
          path: C::Optional[C::Bool]
        ]

      attr_reader :dependency_store

      def initialize(dependency_store)
        @dependency_store = dependency_store
        @stack = []
      end

      contract C_OBJ, C_ARGS => C::Any
      def enter(obj, raw_content: false, attributes: false, compiled_content: false, path: false)
        unless @stack.empty?
          Nanoc::Core::NotificationCenter.post(:dependency_created, @stack.last, obj)
          @dependency_store.record_dependency(
            @stack.last,
            obj,
            raw_content: raw_content,
            attributes: attributes,
            compiled_content: compiled_content,
            path: path,
          )
        end

        @stack.push(obj)
      end

      contract C_OBJ => C::Any
      def exit
        @stack.pop
      end

      contract C_OBJ, C_ARGS => C::Any
      def bounce(obj, raw_content: false, attributes: false, compiled_content: false, path: false)
        enter(obj, raw_content: raw_content, attributes: attributes, compiled_content: compiled_content, path: path)
        exit
      end

      class Null < DependencyTracker
        include Nanoc::Core::ContractsSupport

        def initialize; end

        contract C_OBJ, C_ARGS => C::Any
        def enter(_obj, raw_content: false, attributes: false, compiled_content: false, path: false); end

        contract C_OBJ => C::Any
        def exit; end

        contract C_OBJ, C_ARGS => C::Any
        def bounce(_obj, raw_content: false, attributes: false, compiled_content: false, path: false); end
      end
    end
  end
end
