/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.daffodil.core.dsom

import org.apache.daffodil.core.dsom.IIUtils._
import org.apache.daffodil.lib.api.WarnID
import org.apache.daffodil.lib.xml.XMLUtils

/**
 * Mixin for SchemaSet
 */

trait SchemaSetIncludesAndImportsMixin { self: SchemaSet =>

  /**
   * Let's take the list of file names given, and make a fake schema
   * document with import statements for them. Then the algorithms
   * are all isolated to just the SchemaDocument class and the Include
   * and Import classes.
   */
  lazy val fakeXMLSchemaDocument = {
    val xsd = XMLUtils.XSD_NAMESPACE.toString

    // Any time we synthesize xml we have to grab the namespace definitions and
    // make sure we drag them along onto the new structures.
    val fakeImportStatementsXML =
      <xs:import schemaLocation={schemaSource.uriForLoading.toString} xmlns:xs={xsd}/>

    val fakeSchemaDocXML =
      <xs:schema xmlns:xs={xsd}>{fakeImportStatementsXML}</xs:schema>

    val initialEmptyIIMap: IIMap = IIUtils.emptyIIMap

    val fakeSD = XMLSchemaDocument(
      fakeSchemaDocXML,
      self,
      None,
      None,
      initialEmptyIIMap,
      isBootStrapSD = true
    )
    fakeSD
  }

  lazy val allSchemaDocuments = {
    allSchemaFiles.map { _.iiSchemaDocument }
  }

  lazy val allSchemaFiles = LV(Symbol("allSchemaFiles")) {
    val fd = fakeXMLSchemaDocument // bootstrap
    val sa = fd.seenAfter
    val first = sa.value.head._2.iiSchemaFile
    val sfl = sa.value.flatMap {
      case (_, ii) => {
        val sf =
          ii.iiSchemaFileMaybe // maybe not if we've already seen this file for the same namespace.
        // Require the first schema file to have a DFDL namespace. Other included or imported schemas can be
        // standard XSD schemas but emit a warning that the schema is being ignored.
        sf.filter { f =>
          if (f.isDFDLSchemaFile) {
            true
          } else if (f eq first) {
            f.SDE(
              "Non-DFDL Schema file. Does not have DFDL namespace definition on schema root element.\n" +
                "Add xmlns:dfdl='%s' to the root element.",
              XMLUtils.DFDL_NAMESPACE
            )
            false
          } else {
            f.SDW(
              WarnID.IgnoreImport,
              "Non-DFDL Schema file ignored. Does not have DFDL namespace definition on schema root element.\n" +
                "Add xmlns:dfdl='%s' to the root element if this file must be part of the DFDL schema.",
              XMLUtils.DFDL_NAMESPACE
            )
            false
          }
        }
      }
    }.toList
    sfl
  }.value

}
