# frozen_string_literal: true

require "dry/logic/operators"

require "dry/schema/macros/core"
require "dry/schema/predicate_inferrer"
require "dry/schema/primitive_inferrer"

module Dry
  module Schema
    module Macros
      # Macro specialization used within the DSL
      #
      # @api public
      class DSL < Core
        include Dry::Logic::Operators

        undef :eql?
        undef :nil?

        # @!attribute [r] chain
        #   Indicate if the macro should append its rules to the provided trace
        #   @return [Boolean]
        #   @api private
        option :chain, default: -> { true }

        # @!attribute [r] predicate_inferrer
        #   PredicateInferrer is used to infer predicate type-check from a type spec
        #   @return [PredicateInferrer]
        #   @api private
        option :predicate_inferrer, default: proc { PredicateInferrer.new(compiler.predicates) }

        # @!attribute [r] primitive_inferrer
        #   PrimitiveInferrer used to get a list of primitive classes from configured type
        #   @return [PrimitiveInferrer]
        #   @api private
        option :primitive_inferrer, default: proc { PrimitiveInferrer.new }

        # @overload value(*predicates, **predicate_opts)
        #   Set predicates without and with arguments
        #
        #   @param [Array<Symbol>] predicates
        #   @param [Hash] predicate_opts
        #
        #   @example with a predicate
        #     required(:name).value(:filled?)
        #
        #   @example with a predicate with arguments
        #     required(:name).value(min_size?: 2)
        #
        #   @example with a predicate with and without arguments
        #     required(:name).value(:filled?, min_size?: 2)
        #
        #   @example with a block
        #     required(:name).value { filled? & min_size?(2) }
        #
        # @return [Macros::Core]
        #
        # @api public
        def value(*predicates, &block)
          append_macro(Macros::Value) do |macro|
            macro.call(*predicates, &block)
          end
        end
        ruby2_keywords :value if respond_to?(:ruby2_keywords, true)

        # Prepends `:filled?` predicate
        #
        # @example with a type spec
        #   required(:name).filled(:string)
        #
        # @example with a type spec and a predicate
        #   required(:name).filled(:string, format?: /\w+/)
        #
        # @return [Macros::Core]
        #
        # @api public
        def filled(*args, &block)
          append_macro(Macros::Filled) do |macro|
            macro.call(*args, &block)
          end
        end
        ruby2_keywords :filled if respond_to?(:ruby2_keywords, true)

        # Specify a nested hash without enforced `hash?` type-check
        #
        # This is a simpler building block than `hash` macro, use it
        # when you want to provide `hash?` type-check with other rules
        # manually.
        #
        # @example
        #   required(:tags).value(:hash, min_size?: 1).schema do
        #     required(:name).value(:string)
        #   end
        #
        # @return [Macros::Core]
        #
        # @api public
        def schema(*args, &block)
          append_macro(Macros::Schema) do |macro|
            macro.call(*args, &block)
          end
        end
        ruby2_keywords :schema if respond_to?(:ruby2_keywords, true)

        # Specify a nested hash with enforced `hash?` type-check
        #
        # @example
        #   required(:tags).hash do
        #     required(:name).value(:string)
        #   end
        #
        # @api public
        def hash(*args, &block)
          append_macro(Macros::Hash) do |macro|
            macro.call(*args, &block)
          end
        end
        ruby2_keywords :hash if respond_to?(:ruby2_keywords, true)

        # Specify predicates that should be applied to each element of an array
        #
        # This is a simpler building block than `array` macro, use it
        # when you want to provide `array?` type-check with other rules
        # manually.
        #
        # @example a list of strings
        #   required(:tags).value(:array, min_size?: 2).each(:str?)
        #
        # @example a list of hashes
        #   required(:tags).value(:array, min_size?: 2).each(:hash) do
        #     required(:name).filled(:string)
        #   end
        #
        # @return [Macros::Core]
        #
        # @api public
        def each(*args, &block)
          append_macro(Macros::Each) do |macro|
            macro.value(*args, &block)
          end
        end
        ruby2_keywords :each if respond_to?(:ruby2_keywords, true)

        # Like `each` but sets `array?` type-check
        #
        # @example a list of strings
        #   required(:tags).array(:str?)
        #
        # @example a list of hashes
        #   required(:tags).array(:hash) do
        #     required(:name).filled(:string)
        #   end
        #
        # @return [Macros::Core]
        #
        # @api public
        def array(*args, &block)
          append_macro(Macros::Array) do |macro|
            macro.value(*args, &block)
          end
        end
        ruby2_keywords :array if respond_to?(:ruby2_keywords, true)

        # Set type spec
        #
        # @example
        #   required(:name).type(:string).value(min_size?: 2)
        #
        # @param [Symbol, Array, Dry::Types::Type] spec
        #
        # @return [Macros::Key]
        #
        # @api public
        def type(spec)
          schema_dsl.set_type(name, spec)
          self
        end

        # @api private
        def custom_type?
          schema_dsl.custom_type?(name)
        end

        private

        # @api private
        def append_macro(macro_type)
          macro = macro_type.new(schema_dsl: schema_dsl, name: name)

          yield(macro)

          if chain
            trace << macro
            self
          else
            macro
          end
        end

        # @api private
        def extract_type_spec(*args, nullable: false, set_type: true)
          type_spec = args[0] unless schema_or_predicate?(args[0])

          predicates = Array(type_spec ? args[1..-1] : args)
          type_rule = nil

          if type_spec
            resolved_type = resolve_type(type_spec, nullable)

            if type_spec.is_a?(::Array)
              type_rule = type_spec.map { |ts| new(chain: false).value(ts) }.reduce(:|)
            else
              type_predicates = predicate_inferrer[resolved_type]

              predicates.replace(type_predicates + predicates) unless type_predicates.empty?

              return self if predicates.empty?
            end
          end

          type(resolved_type) if set_type && resolved_type

          if type_rule
            yield(*predicates, type_spec: nil, type_rule: type_rule)
          else
            yield(*predicates, type_spec: type_spec, type_rule: nil)
          end
        end

        # @api private
        def resolve_type(type_spec, nullable)
          resolved = schema_dsl.resolve_type(type_spec)

          if type_spec.is_a?(::Array) || !nullable || resolved.optional?
            resolved
          else
            schema_dsl.resolve_type([:nil, resolved])
          end
        end

        # @api private
        def schema_or_predicate?(arg)
          arg.is_a?(Dry::Schema::Processor) ||
            arg.is_a?(Symbol) &&
              arg.to_s.end_with?(QUESTION_MARK)
        end
      end
    end
  end
end