# frozen_string_literal: true

require "test_prof/any_fixture/dump/digest"

require "set"

module TestProf
  module AnyFixture
    MODIFY_RXP = /^(INSERT INTO|UPDATE|DELETE FROM) (\S+)/i.freeze
    ANY_FIXTURE_RXP = /(\/\*|--).*\bany_fixture:dump/.freeze
    ANY_FIXTURE_IGNORE_RXP = /(\/\*|--).*\bany_fixture:ignore/.freeze

    using(Module.new do
      refine Object do
        def to_digest
          to_s
        end
      end

      refine NilClass do
        def to_digest
          nil
        end
      end

      refine Hash do
        def to_digest
          map { |k, v| [k.to_digest, v.to_digest].compact.join("_") }
        end
      end

      refine Array do
        def to_digest
          map { |v| v.to_digest }.compact.join("-")
        end
      end
    end)

    class Dump
      class Subscriber
        attr_reader :path, :tmp_path

        def initialize(path, adapter)
          @path = path
          @adapter = adapter
          @tmp_path = path + ".tmp"
          @reset_pk = Set.new
        end

        def start(_event, _id, payload)
          sql = payload.fetch(:sql)
          return if sql.match?(ANY_FIXTURE_IGNORE_RXP)

          matches = sql.match(MODIFY_RXP)
          return unless matches

          reset_pk!(matches[2]) if /insert/i.match?(matches[1])
        end

        def finish(_event, _id, payload)
          sql = payload.fetch(:sql)
          return unless trackable_sql?(sql)

          sql = payload[:binds].any? ? adapter.compile_sql(sql, quoted(payload[:binds])) : +sql

          sql.tr!("\n", " ")

          file.write(sql + ";\n")
        end

        def commit
          return unless instance_variable_defined?(:@file)

          file.close

          FileUtils.mv(tmp_path, path)
        end

        private

        attr_reader :reset_pk, :adapter

        def file
          @file ||= File.open(tmp_path, "w")
        end

        def reset_pk!(table_name)
          return if /sqlite_sequence/.match?(table_name)

          return if reset_pk.include?(table_name)

          adapter.reset_sequence!(table_name, AnyFixture.config.dump_sequence_random_start)
          reset_pk << table_name
        end

        def trackable_sql?(sql)
          return false if sql.match?(ANY_FIXTURE_IGNORE_RXP)

          sql.match?(MODIFY_RXP) || sql.match?(ANY_FIXTURE_RXP) || sql.match?(AnyFixture.config.dump_matching_queries)
        end

        def quoted(val)
          if val.is_a?(Array)
            val.map { |v| quoted(v) }
          elsif val.is_a?(ActiveModel::Attribute)
            quoted(val.value_for_database)
          else
            ActiveRecord::Base.connection.quote(val)
          end
        end
      end

      attr_reader :name, :digest, :path, :subscriber, :success
      alias_method :success?, :success

      def initialize(name, watch: [], cache_key: nil)
        @name = name
        @digest = [
          Digest.call(*watch),
          cache_key.to_digest
        ].compact.join("-")

        @path = build_path(name, digest)

        @success = false

        @adapter =
          case ActiveRecord::Base.connection.adapter_name
          when /sqlite/i
            require "test_prof/any_fixture/dump/sqlite"
            SQLite.new
          when /postgresql/i
            require "test_prof/any_fixture/dump/postgresql"
            PostgreSQL.new
          else
            raise ArgumentError,
              "Your current database adapter (#{ActiveRecord::Base.connection.adapter_name}) " \
              "is currently not supported. So far, we only support SQLite and PostgreSQL"
          end

        @subscriber = Subscriber.new(path, adapter)
      end

      def exists?
        File.exist?(path)
      end

      def force?
        AnyFixture.config.force_matching_dumps.match?(name)
      end

      def load
        return import_via_active_record unless AnyFixture.config.import_dump_via_cli?

        adapter.import(path) || import_via_active_record
      end

      def commit!
        subscriber.commit
      end

      def within_prepared_env(before: nil, after: nil, import: false)
        run_before_callbacks(callback: before, dump: self, import: false)
        yield.tap do
          @success = true
        end
      ensure
        run_after_callbacks(callback: after, dump: self, import: false)
      end

      private

      attr_reader :adapter

      def import_via_active_record
        conn = ActiveRecord::Base.connection

        File.open(path).each_line do |query|
          next if query.empty?

          conn.execute query
        end
      end

      def build_path(name, digest)
        dir = TestProf.artifact_path(
          File.join(AnyFixture.config.dumps_dir)
        )

        FileUtils.mkdir_p(dir)

        File.join(dir, "#{name}-#{digest}.sql")
      end

      def run_before_callbacks(callback:, **options)
        # First, call config-defined setup callbacks
        AnyFixture.config.before_dump.each { |clbk| clbk.call(**options) }
        # Then, adapter-defined callbacks
        adapter.setup_env unless options[:import]
        # Finally, user-provided callback
        callback&.call(**options)
      end

      def run_after_callbacks(callback:, **options)
        # The order is vice versa to setup
        callback&.call(**options)
        adapter.teardown_env unless options[:import]
        AnyFixture.config.after_dump.each { |clbk| clbk.call(**options) }
      end
    end
  end
end