# frozen_string_literal: true

module AR
  module Enum
    module Adapter
      def enum_types
        execute <<~SQL
          with
          sorted_enums as (
            select
              t.typname,
              e.enumlabel
            from
              pg_type t,
              pg_enum e
            where
              t.oid = e.enumtypid
            order by
              e.enumsortorder
          )

          select
            typname as name,
            string_agg(enumlabel, ',') as labels
          from
            sorted_enums
          group by
            typname
        SQL
      end

      def create_enum(name, values)
        return if enum_exists?(name)

        values = values.map do |value|
          quote(value.to_s)
        end

        sql = <<-SQL
          CREATE TYPE #{name}
          AS ENUM (#{values.join(', ')})
        SQL

        execute(sql)
      end

      def enum_exists?(name)
        enum_types.any? {|type| type["name"] == name.to_s }
      end

      def add_enum_label(name, value, options = {})
        sql = "ALTER TYPE #{name} ADD VALUE #{quote(value.to_s)}"

        if options[:before]
          sql = "#{sql} BEFORE #{quote(options[:before].to_s)}"
        elsif options[:after]
          sql = "#{sql} AFTER #{quote(options[:after].to_s)}"
        end

        execute(sql)
      end

      def rename_enum_label(name, from, to)
        sql = "ALTER TYPE #{name} RENAME VALUE #{quote(from.to_s)} TO #{quote(to.to_s)}"
        execute(sql)
      end

      def drop_enum(name, options = {})
        sql = "DROP TYPE IF EXISTS #{name}"
        sql = "#{sql} CASCADE" if options[:cascade]

        execute(sql)
      end
    end
  end
end