# frozen_string_literal: true

require 'plumb/visitor_handlers'

module Plumb
  class MetadataVisitor
    include VisitorHandlers

    def self.call(type)
      new.visit(type)
    end

    def on_missing_handler(type, props, method_name)
      return props.merge(type: type) if type.class == Class

      puts "Missing handler for #{type.inspect} with props #{props.inspect} and method_name :#{method_name}"
      props
    end

    on(:undefined) do |type, props|
      props
    end

    on(:any) do |type, props|
      props
    end

    on(:pipeline) do |type, props|
      visit(type.type, props)
    end

    on(:step) do |type, props|
      props.merge(type._metadata)
    end

    on(::Regexp) do |type, props|
      props.merge(pattern: type)
    end

    on(::Range) do |type, props|
      props.merge(match: type)
    end

    on(:match) do |type, props|
      visit(type.matcher, props)
    end

    on(:hash) do |type, props|
      props.merge(type: Hash)
    end

    on(:and) do |type, props|
      left = visit(type.left)
      right = visit(type.right)
      type = right[:type] || left[:type]
      props = props.merge(left).merge(right)
      props = props.merge(type:) if type
      props
    end

    on(:or) do |type, props|
      child_metas = [visit(type.left), visit(type.right)]
      types = child_metas.map { |child| child[:type] }.flatten.compact
      types = types.first if types.size == 1
      child_metas.reduce(props) do |acc, child|
        acc.merge(child)
      end.merge(type: types)
    end

    on(:value) do |type, props|
      visit(type.value, props)
    end

    on(:transform) do |type, props|
      props.merge(type: type.target_type)
    end

    on(:static) do |type, props|
      props.merge(static: type.value)
    end

    on(:rules) do |type, props|
      type.rules.reduce(props) do |acc, rule|
        acc.merge(rule.name => rule.arg_value)
      end
    end

    on(:boolean) do |type, props|
      props.merge(type: 'boolean')
    end

    on(:metadata) do |type, props|
      props.merge(type.metadata)
    end

    on(:hash_map) do |type, props|
      props.merge(type: Hash)
    end

    on(:build) do |type, props|
      visit(type.type, props)
    end

    on(:array) do |type, props|
      props.merge(type: Array)
    end

    on(:tuple) do |type, props|
      props.merge(type: Array)
    end

    on(:tagged_hash) do |type, props|
      props.merge(type: Hash)
    end
  end
end