/*
    * SPDX-FileCopyrightText: none
    * SPDX-License-Identifier: CC0-1.0
    */
   
   package dev.metaschema.oscal.lib.metapath.function.library;
   
   import java.io.IOException;
   import java.net.URI;
  import java.util.List;
  
  import dev.metaschema.core.metapath.DynamicContext;
  import dev.metaschema.core.metapath.MetapathConstants;
  import dev.metaschema.core.metapath.function.DocumentFunctionException;
  import dev.metaschema.core.metapath.function.FunctionUtils;
  import dev.metaschema.core.metapath.function.IArgument;
  import dev.metaschema.core.metapath.function.IFunction;
  import dev.metaschema.core.metapath.function.library.FnDoc;
  import dev.metaschema.core.metapath.function.library.FnResolveUri;
  import dev.metaschema.core.metapath.item.IItem;
  import dev.metaschema.core.metapath.item.ISequence;
  import dev.metaschema.core.metapath.item.atomic.IAnyUriItem;
  import dev.metaschema.core.metapath.item.node.IDocumentNodeItem;
  import dev.metaschema.core.metapath.item.node.INodeItem;
  import dev.metaschema.core.util.ObjectUtils;
  import dev.metaschema.oscal.lib.OscalModelConstants;
  import dev.metaschema.oscal.lib.model.Catalog;
  import dev.metaschema.oscal.lib.profile.resolver.ProfileResolutionException;
  import dev.metaschema.oscal.lib.profile.resolver.ProfileResolver;
  import edu.umd.cs.findbugs.annotations.NonNull;
  
  public final class ResolveProfile {
  
    @NonNull
    static final IFunction SIGNATURE_NO_ARG = IFunction.builder()
        .name("resolve-profile")
        .namespace(OscalModelConstants.NS_OSCAL)
        .returnType(INodeItem.type())
        .focusDependent()
        .contextDependent()
        .deterministic()
        .returnOne()
        .functionHandler(ResolveProfile::executeNoArg)
        .build();
  
    @NonNull
    static final IFunction SIGNATURE_ONE_ARG = IFunction.builder()
        .name("resolve-profile")
        .namespace(OscalModelConstants.NS_OSCAL)
        .argument(IArgument.builder()
            .name("profile")
            .type(INodeItem.type())
            .zeroOrOne()
            .build())
        .focusIndependent()
        .contextDependent()
        .deterministic()
        .returnType(INodeItem.type())
        .returnOne()
        .functionHandler(ResolveProfile::executeOneArg)
        .build();
  
    @NonNull
    static final IFunction SIGNATURE_NO_ARG_METAPATH = IFunction.builder()
        .name("resolve-profile")
        .namespace(MetapathConstants.NS_METAPATH_FUNCTIONS)
        .returnType(INodeItem.type())
        .focusDependent()
        .contextDependent()
        .deterministic()
        .returnOne()
        .functionHandler(ResolveProfile::executeNoArg)
        .build();
  
    @NonNull
    static final IFunction SIGNATURE_ONE_ARG_METAPATH = IFunction.builder()
        .name("resolve-profile")
        .namespace(MetapathConstants.NS_METAPATH_FUNCTIONS)
        .argument(IArgument.builder()
            .name("profile")
            .type(INodeItem.type())
            .zeroOrOne()
            .build())
        .focusIndependent()
        .contextDependent()
        .deterministic()
        .returnType(INodeItem.type())
        .returnOne()
        .functionHandler(ResolveProfile::executeOneArg)
        .build();
  
    private ResolveProfile() {
      // disable construction
    }
  
    @SuppressWarnings({ "unused",
        "PMD.OnlyOneReturn" // readability
    })
    @NonNull
   public static ISequence<?> executeNoArg(
       @NonNull IFunction function,
       @NonNull List<ISequence<?>> arguments,
       @NonNull DynamicContext dynamicContext,
       IItem focus) {
 
     if (focus == null) {
       return ISequence.empty();
     }
     return ISequence.of(resolveProfile(FunctionUtils.asType(focus), dynamicContext));
   }
 
   @SuppressWarnings({ "unused",
       "PMD.OnlyOneReturn" // readability
   })
   @NonNull
   public static ISequence<?> executeOneArg(
       @NonNull IFunction function,
       @NonNull List<ISequence<?>> arguments,
       @NonNull DynamicContext dynamicContext,
       IItem focus) {
     ISequence<? extends IDocumentNodeItem> arg = FunctionUtils.asType(
         ObjectUtils.notNull(arguments.get(0)));
 
     IItem item = arg.getFirstItem(true);
     if (item == null) {
       return ISequence.empty();
     }
 
     return ISequence.of(resolveProfile(FunctionUtils.asType(item), dynamicContext));
   }
 
   @NonNull
   public static IDocumentNodeItem resolveProfile(
       @NonNull IDocumentNodeItem document,
       @NonNull DynamicContext dynamicContext) {
 
     // make this work with unresolved fragments
     URI documentUri = document.getBaseUri();
     String fragment = documentUri.getFragment();
 
     IDocumentNodeItem profile;
     if (fragment == null) {
       profile = document;
     } else {
       IAnyUriItem referenceUri = ResolveReference.resolveReference(IAnyUriItem.valueOf(documentUri), null, document);
       IAnyUriItem resolvedUri = FnResolveUri.fnResolveUri(referenceUri, null, dynamicContext);
       profile = FnDoc.fnDoc(resolvedUri, dynamicContext);
     }
 
     Object profileObject = INodeItem.toValue(profile);
 
     IDocumentNodeItem retval;
     if (profileObject instanceof Catalog) {
       retval = profile;
     } else {
       // this is a profile
       ProfileResolver resolver
           = new ProfileResolver(dynamicContext, (uri, source) -> profile.getDocumentUri().resolve(uri));
       try {
         retval = resolver.resolve(profile);
       } catch (IOException | ProfileResolutionException ex) {
         throw new DocumentFunctionException(
             DocumentFunctionException.ERROR_RETRIEVING_RESOURCE,
             String.format("Unable to resolve profile '%s'. %s",
                 profile.getBaseUri(),
                 ex.getLocalizedMessage()),
             ex);
       }
     }
     return retval;
   }
 }