// Copyright 2014 The Bazel Authors. All rights reserved.
//
// Licensed 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 com.google.devtools.build.lib.rules.objc;

import static com.google.devtools.build.lib.rules.objc.XcodeProductType.LIBRARY_STATIC;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
import com.google.devtools.build.lib.analysis.RuleContext;
import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
import com.google.devtools.build.lib.rules.cpp.CcLinkParams;
import com.google.devtools.build.lib.rules.cpp.CcLinkParamsProvider;
import com.google.devtools.build.lib.rules.cpp.CcLinkParamsStore;
import com.google.devtools.build.lib.rules.cpp.CppCompilationContext;
import com.google.devtools.build.lib.rules.cpp.LinkerInputs;
import com.google.devtools.build.lib.rules.cpp.LinkerInputs.LibraryToLink;
import com.google.devtools.build.lib.rules.objc.ObjcCommon.CompilationAttributes;
import com.google.devtools.build.lib.rules.objc.ObjcCommon.ResourceAttributes;
import com.google.devtools.build.lib.rules.test.InstrumentedFilesProvider;
import com.google.devtools.build.lib.syntax.Type;

/**
 * Implementation for {@code objc_library}.
 */
public class ObjcLibrary implements RuleConfiguredTargetFactory {

  /**
   * A {@link CcLinkParamsStore} to be propagated to dependent cc_{library, binary} targets.
   */
  private static class ObjcLibraryCcLinkParamsStore extends CcLinkParamsStore {

    private ObjcCommon common;

    public ObjcLibraryCcLinkParamsStore(ObjcCommon common) {
      this.common = common;
    }

    @Override
    protected void collect(
        CcLinkParams.Builder builder, boolean linkingStatically, boolean linkShared) {
      ObjcProvider objcProvider = common.getObjcProvider();

      ImmutableSet.Builder<LibraryToLink> libraries = new ImmutableSet.Builder<>();
      for (Artifact library : objcProvider.get(ObjcProvider.LIBRARY)) {
        libraries.add(LinkerInputs.opaqueLibraryToLink(library));
      }

      libraries.addAll(objcProvider.get(ObjcProvider.CC_LIBRARY));

      builder.addLibraries(libraries.build());
    }
  }

  /**
   * Constructs an {@link ObjcCommon} instance based on the attributes of the given rule. The rule
   * should inherit from {@link ObjcLibraryRule}..
   */
  static ObjcCommon common(RuleContext ruleContext, Iterable<SdkFramework> extraSdkFrameworks,
      boolean alwayslink, Iterable<ObjcProvider> extraDepObjcProviders) {
    CompilationArtifacts compilationArtifacts =
        CompilationSupport.compilationArtifacts(ruleContext);

    return new ObjcCommon.Builder(ruleContext)
        .setCompilationAttributes(new CompilationAttributes(ruleContext))
        .setResourceAttributes(new ResourceAttributes(ruleContext))
        .addExtraSdkFrameworks(extraSdkFrameworks)
        .addDefines(ruleContext.getTokenizedStringListAttr("defines"))
        .setCompilationArtifacts(compilationArtifacts)
        .addDepObjcProviders(ruleContext.getPrerequisites("deps", Mode.TARGET, ObjcProvider.class))
        .addDepObjcProviders(
            ruleContext.getPrerequisites("bundles", Mode.TARGET, ObjcProvider.class))
        .addNonPropagatedDepObjcProviders(
            ruleContext.getPrerequisites("non_propagated_deps", Mode.TARGET, ObjcProvider.class))
        .addDepCcHeaderProviders(
            ruleContext.getPrerequisites("deps", Mode.TARGET, CppCompilationContext.class))
        .addDepCcLinkProviders(ruleContext)
        .setIntermediateArtifacts(ObjcRuleClasses.intermediateArtifacts(ruleContext))
        .setAlwayslink(alwayslink)
        .setHasModuleMap()
        .addDepObjcProviders(extraDepObjcProviders)
        .build();
  }

  @Override
  public ConfiguredTarget create(RuleContext ruleContext) throws InterruptedException {
    final ObjcCommon common =
        common(
            ruleContext,
            ImmutableList.<SdkFramework>of(),
            ruleContext.attributes().get("alwayslink", Type.BOOLEAN),
            ImmutableList.<ObjcProvider>of());

    XcodeProvider.Builder xcodeProviderBuilder = new XcodeProvider.Builder();
    NestedSetBuilder<Artifact> filesToBuild = NestedSetBuilder.<Artifact>stableOrder()
        .addAll(common.getCompiledArchive().asSet());

    CompilationSupport compilationSupport =
        new CompilationSupport(ruleContext)
            .registerCompileAndArchiveActions(common)
            .addXcodeSettings(xcodeProviderBuilder, common)
            .validateAttributes();

    new ResourceSupport(ruleContext)
        .validateAttributes()
        .addXcodeSettings(xcodeProviderBuilder);

    new XcodeSupport(ruleContext)
        .addFilesToBuild(filesToBuild)
        .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), LIBRARY_STATIC)
        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
        .addDependencies(xcodeProviderBuilder, new Attribute("deps", Mode.TARGET))
        .addNonPropagatedDependencies(
            xcodeProviderBuilder, new Attribute("non_propagated_deps", Mode.TARGET))
        .registerActions(xcodeProviderBuilder.build());

    return ObjcRuleClasses.ruleConfiguredTarget(ruleContext, filesToBuild.build())
        .addProvider(XcodeProvider.class, xcodeProviderBuilder.build())
        .addProvider(ObjcProvider.class, common.getObjcProvider())
        .addProvider(
            J2ObjcEntryClassProvider.class, J2ObjcEntryClassProvider.buildFrom(ruleContext))
        .addProvider(
            J2ObjcMappingFileProvider.class, ObjcRuleClasses.j2ObjcMappingFileProvider(ruleContext))
        .addProvider(
            InstrumentedFilesProvider.class,
            compilationSupport.getInstrumentedFilesProvider(common))
        .addProvider(
            CcLinkParamsProvider.class,
            new CcLinkParamsProvider(new ObjcLibraryCcLinkParamsStore(common)))
        .addSkylarkTransitiveInfo(
            ObjcProvider.OBJC_SKYLARK_PROVIDER_NAME, common.getObjcProvider().toSkylarkProvider())
        .build();
  }
}