# frozen_string_literal: true

require 'java'
require_relative '../../../../java/saxon9he.jar'

java_import 'java.io.StringReader'
java_import 'java.io.StringWriter'

java_import 'javax.xml.parsers.DocumentBuilder'
java_import 'javax.xml.parsers.DocumentBuilderFactory'

java_import 'javax.xml.transform.TransformerFactory'
java_import 'javax.xml.transform.Transformer'
java_import 'javax.xml.transform.dom.DOMSource'
java_import 'javax.xml.transform.stream.StreamSource'
java_import 'javax.xml.transform.stream.StreamResult'

java_import 'org.w3c.dom.Document'

TRANSFORMER_FACTORY_IMPL = 'net.sf.saxon.TransformerFactoryImpl'

module CqmValidators
  module Schematron
    module JavaProcessor
      ISO_SCHEMATRON2 = File.join(DIR, 'lib/schematron/iso-schematron-xslt2/iso_svrl_for_xslt2.xsl')

      class HdsUrlResolver
        include javax.xml.transform.URIResolver

        def initialize(schematron)
          @file = schematron
        end

        def resolve(href, _base)
          path = File.join(File.dirname(@file), href)
          StreamSource.new(java.io.File.new(path))
        end
      end

      def get_errors(document)
        document_j = get_document_j(document)
        output = build_transformer(StringReader.new(processor), StreamSource.new(document_j), true)
        Nokogiri::XML(output)
      end

      def get_document_j(doc)
        case doc
        when File
          java.io.File.new(doc.path)
        else
          StringReader.new(doc.to_s)
        end
      end

      def processor
        @processor ||= build_transformer(java.io.File.new(ISO_SCHEMATRON2), schematron_file)
      end

      def schematron_file
        # this allows us to run the validation utility app in jBoss/TorqueBox
        # for some reason it breaks the first time you call DocumentBuilderFactory,
        # so the solution is to catch the error and retry
        # TODO: pull this out when the above is no longer the case.
        begin
          dbf = DocumentBuilderFactory.new_instance
        rescue Exception
          retry
        end
        dbf.setIgnoringElementContentWhitespace(true)
        db = dbf.new_document_builder
        document = db.parse(java.io.File.new(@schematron_file))

        root = document.document_element
        root.set_attribute('defaultPhase', 'errors')

        DOMSource.new(root)
      end

      def build_transformer(xslt, input_file, url = false)
        factory = TransformerFactory.newInstance(TRANSFORMER_FACTORY_IMPL, nil)
        factory.uri_resolver = HdsUrlResolver.new(@schematron_file) if url
        transformer = factory.new_transformer(StreamSource.new(xslt))
        sw = StringWriter.new
        output = StreamResult.new(sw)
        transformer.transform(input_file, output)
        sw.to_s
      end
    end
  end
end