# frozen_string_literal: true

module Ridgepole
  class DSLParser
    def initialize(options = {})
      @options = options
    end

    def parse(dsl, opts = {})
      definition, execute = Context.eval(dsl, opts)
      check_definition(definition)
      [definition, execute]
    end

    private

    def check_definition(definition)
      definition.each do |table_name, attrs|
        check_orphan_index(table_name, attrs)
        check_orphan_foreign_key(table_name, attrs)
        check_foreign_key_without_index(table_name, attrs)
      end
    end

    def check_orphan_index(table_name, attrs)
      raise "Table `#{table_name}` to create the index is not defined: #{attrs[:indices].keys.join(',')}" if attrs[:indices] && !(attrs[:definition])
    end

    def check_orphan_foreign_key(table_name, attrs)
      raise "Table `#{table_name}` to create the foreign key is not defined: #{attrs[:foreign_keys].keys.join(',')}" if attrs[:foreign_keys] && !(attrs[:definition])
    end

    def check_foreign_key_without_index(table_name, attrs)
      return unless attrs[:foreign_keys]
      return unless attrs[:options][:options]&.include?('ENGINE=InnoDB')

      attrs[:foreign_keys].each do |_, foreign_key_attrs|
        fk_index = foreign_key_attrs[:options][:column] || "#{foreign_key_attrs[:to_table].singularize}_id"
        next if attrs[:indices]&.any? { |_k, v| v[:column_name].first == fk_index }
        # NOTE: For composite primary keys, the first column of the primary key is used as the foreign key index
        next if Array(attrs[:options][:primary_key]).first == fk_index

        raise("The column `#{fk_index}` of the table `#{table_name}` has a foreign key but no index." \
              ' Although InnoDB creates an index automatically,' \
              ' please add one explicitly in order for ridgepole to manage it.')
      end
    end
  end
end