/*
    * #%L
    * Native ARchive plugin for Maven
    * %%
    * Copyright (C) 2002 - 2014 NAR Maven Plugin developers.
    * %%
    * 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.
   * #L%
   */
  package com.github.maven_nar.cpptasks.apple;
  
  import java.io.File;
  import java.io.IOException;
  import java.text.NumberFormat;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Comparator;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  
  import javax.xml.transform.TransformerConfigurationException;
  
  import org.apache.tools.ant.BuildException;
  import org.xml.sax.SAXException;
  
  import com.github.maven_nar.cpptasks.CCTask;
  import com.github.maven_nar.cpptasks.CUtil;
  import com.github.maven_nar.cpptasks.TargetInfo;
  import com.github.maven_nar.cpptasks.compiler.CommandLineCompilerConfiguration;
  import com.github.maven_nar.cpptasks.compiler.CommandLineLinkerConfiguration;
  import com.github.maven_nar.cpptasks.compiler.ProcessorConfiguration;
  import com.github.maven_nar.cpptasks.gcc.GccCCompiler;
  import com.github.maven_nar.cpptasks.ide.CommentDef;
  import com.github.maven_nar.cpptasks.ide.DependencyDef;
  import com.github.maven_nar.cpptasks.ide.ProjectDef;
  import com.github.maven_nar.cpptasks.ide.ProjectWriter;
  
  /**
   * Writes a Apple Xcode 2.1+ project directory. XCode stores project
   * configuration as a PropertyList. Though it will always write the project
   * as a Cocoa Old-Style ASCII property list, it will read projects
   * stored using Cocoa's XML Property List format.
   */
  public final class XcodeProjectWriter implements ProjectWriter {
  
    /**
     * Represents a property map with an 96 bit identity.
     * When placed in a property list, this object will
     * output the string representation of the identity
     * which XCode uses to find the corresponding property
     * bag in the "objects" property of the top-level property list.
     */
    private static final class PBXObjectRef {
      /**
       * Next available identifier.
       */
      private static int nextID = 0;
      /**
       * Identifier.
       */
      private final String id;
      /**
       * Properties.
       */
      private final Map properties;
  
      /**
       * Create reference.
       * 
       * @param props
       *          properties.
       */
      public PBXObjectRef(final Map props) {
        if (props == null) {
          throw new NullPointerException("props");
        }
        final StringBuffer buf = new StringBuffer("000000000000000000000000");
        final String idStr = Integer.toHexString(nextID++);
        buf.replace(buf.length() - idStr.length(), buf.length(), idStr);
        this.id = buf.toString();
        this.properties = props;
      }
  
      /**
       * Get object identifier.
       * 
      * @return object identifier.
      */
     public String getID() {
       return this.id;
     }
 
     /**
      * Get properties.
      * 
      * @return properties.
      */
     public Map getProperties() {
       return this.properties;
     }
 
     /**
      * Get object identifier.
      * 
      * @return identifier.
      */
     @Override
     public String toString() {
       return this.id;
     }
   }
 
   /**
    * Create PBXBuildFile.
    * 
    * @param fileRef
    *          source file.
    * @param settings
    *          build settings.
    * @return PBXBuildFile.
    */
   private static PBXObjectRef createPBXBuildFile(final PBXObjectRef fileRef, final Map settings) {
     final Map map = new HashMap();
     map.put("fileRef", fileRef);
     map.put("isa", "PBXBuildFile");
     if (settings != null) {
       map.put("settings", settings);
     }
     return new PBXObjectRef(map);
   }
 
   /**
    * Create a proxy for a file in a different project.
    * 
    * @param containerPortal
    *          XcodeProject containing file.
    * @param proxyType
    *          proxy type.
    * @return PBXContainerItemProxy.
    */
   private static PBXObjectRef createPBXContainerItemProxy(final PBXObjectRef containerPortal, final int proxyType,
       final String remoteInfo) {
     final Map map = new HashMap();
     map.put("isa", "PBXContainerItemProxy");
     map.put("containerPortal", containerPortal);
     map.put("proxyType", NumberFormat.getIntegerInstance(Locale.US).format(proxyType));
     map.put("remoteInfo", remoteInfo);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create a build phase that copies files to a destination.
    * 
    * @param buildActionMask
    *          build action mask.
    * @param dstPath
    *          destination path.
    * @param dstSubfolderSpec
    *          subfolder spec.
    * @param files
    *          files.
    * @param runOnly
    *          if true, phase should only be run on deployment.
    * @return PBXCopyFileBuildPhase.
    */
   private static PBXObjectRef createPBXCopyFilesBuildPhase(final int buildActionMask, final String dstPath,
       final String dstSubfolderSpec, final List files, final boolean runOnly) {
     final Map map = new HashMap();
     map.put("isa", "PBXCopyFilesBuildPhase");
     map.put("buildActionMask", NumberFormat.getIntegerInstance(Locale.US).format(buildActionMask));
     map.put("dstPath", dstPath);
     map.put("dstSubfolderSpec", dstSubfolderSpec);
     map.put("files", files);
     map.put("runOnlyForDeploymentPostprocessing", toString(runOnly));
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXFileReference.
    * 
    * @param sourceTree
    *          source tree.
    * @param baseDir
    *          base directory.
    * @param file
    *          file.
    * @return PBXFileReference object.
    */
   private static PBXObjectRef createPBXFileReference(final String sourceTree, final String baseDir, final File file) {
     final Map map = new HashMap();
     map.put("isa", "PBXFileReference");
 
     final String relPath = CUtil.toUnixPath(CUtil.getRelativePath(baseDir, file));
     map.put("path", relPath);
     map.put("name", file.getName());
     map.put("sourceTree", sourceTree);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXFrameworksBuildPhase.
    * 
    * @param buildActionMask
    *          build action mask.
    * @param files
    *          files.
    * @param runOnly
    *          if true, phase should only be run on deployment.
    * @return PBXFrameworkBuildPhase.
    */
   private static PBXObjectRef createPBXFrameworksBuildPhase(final int buildActionMask, final List files,
       final boolean runOnly) {
     final Map map = new HashMap();
     map.put("isa", "PBXFrameworksBuildPhase");
     map.put("buildActionMask", NumberFormat.getIntegerInstance(Locale.US).format(buildActionMask));
     map.put("files", files);
     map.put("runOnlyForDeploymentPostprocessing", toString(runOnly));
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXGroup.
    * 
    * @param name
    *          group name.
    * @param sourceTree
    *          source tree.
    * @param children
    *          list of PBXFileReferences.
    * @return group.
    */
   private static PBXObjectRef createPBXGroup(final String name, final String sourceTree, final List children) {
     final Map map = new HashMap();
     map.put("isa", "PBXGroup");
     map.put("name", name);
     map.put("sourceTree", sourceTree);
     map.put("children", children);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXNativeTarget.
    * 
    * @param name
    *          name.
    * @param buildConfigurationList
    *          build configuration list.
    * @param buildPhases
    *          build phases.
    * @param buildRules
    *          build rules.
    * @param dependencies
    *          dependencies.
    * @param productInstallPath
    *          product install path.
    * @param productName
    *          product name.
    * @param productReference
    *          file reference for product.
    * @param productType
    *          product type.
    * @return native target.
    */
   private static PBXObjectRef createPBXNativeTarget(final String name, final PBXObjectRef buildConfigurationList,
       final List buildPhases, final List buildRules, final List dependencies, final String productInstallPath,
       final String productName, final PBXObjectRef productReference, final String productType) {
     final Map map = new HashMap();
     map.put("isa", "PBXNativeTarget");
     map.put("buildConfigurationList", buildConfigurationList);
     map.put("buildPhases", buildPhases);
     map.put("buildRules", buildRules);
     map.put("dependencies", dependencies);
     map.put("name", name);
     map.put("productInstallPath", productInstallPath);
     map.put("productName", productName);
     map.put("productReference", productReference);
     map.put("productType", productType);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXProject.
    * 
    * @param buildConfigurationList
    *          build configuration list.
    * @param mainGroup
    *          main group.
    * @param projectDirPath
    *          project directory path.
    * @param targets
    *          targets.
    * @param projectRoot
    *          projectRoot directory relative to
    * @return project.
    */
   private static PBXObjectRef createPBXProject(final PBXObjectRef buildConfigurationList, final PBXObjectRef mainGroup,
       final String projectDirPath, final String projectRoot, final List targets) {
     final Map map = new HashMap();
     map.put("isa", "PBXProject");
     map.put("buildConfigurationList", buildConfigurationList.getID());
     map.put("hasScannedForEncodings", "0");
     map.put("mainGroup", mainGroup.getID());
     map.put("projectDirPath", projectDirPath);
     map.put("targets", targets);
     map.put("projectRoot", projectRoot);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create a proxy for a file in a different project.
    * 
    * @param remoteRef
    *          PBXContainerItemProxy for reference.
    * @param dependency
    *          dependency.
    * @return PBXContainerItemProxy.
    */
   private static PBXObjectRef createPBXReferenceProxy(final PBXObjectRef remoteRef, final DependencyDef dependency) {
     final Map map = new HashMap();
     map.put("isa", "PBXReferenceProxy");
     final String fileType = "compiled.mach-o.dylib";
     map.put("fileType", fileType);
     map.put("remoteRef", remoteRef);
     map.put("path", dependency.getFile().getName() + ".dylib");
     map.put("sourceTree", "BUILT_PRODUCTS_DIR");
     return new PBXObjectRef(map);
   }
 
   /**
    * Create PBXSourcesBuildPhase.
    * 
    * @param buildActionMask
    *          build action mask.
    * @param files
    *          source files.
    * @param runOnly
    *          if true, phase should only be run on deployment.
    * @return PBXSourcesBuildPhase.
    */
   private static PBXObjectRef createPBXSourcesBuildPhase(final int buildActionMask, final List files,
       final boolean runOnly) {
     final Map map = new HashMap();
     map.put("buildActionMask", String.valueOf(buildActionMask));
     map.put("files", files);
     map.put("isa", "PBXSourcesBuildPhase");
     map.put("runOnlyForDeploymentPostprocessing", toString(runOnly));
     return new PBXObjectRef(map);
   }
 
   /**
    * Create XCBuildConfiguration.
    * 
    * @param name
    *          name.
    * @param buildSettings
    *          build settings.
    * @return build configuration.
    */
   private static PBXObjectRef createXCBuildConfiguration(final String name, final Map<String, ?> buildSettings) {
     final Map map = new HashMap();
     map.put("isa", "XCBuildConfiguration");
     map.put("buildSettings", buildSettings);
     map.put("name", name);
     return new PBXObjectRef(map);
   }
 
   /**
    * Create XCConfigurationList.
    * 
    * @param buildConfigurations
    *          build configurations.
    * @return configuration list.
    */
   private static PBXObjectRef createXCConfigurationList(final List buildConfigurations) {
     final Map map = new HashMap();
     map.put("isa", "XCConfigurationList");
     map.put("buildConfigurations", buildConfigurations);
     return new PBXObjectRef(map);
   }
 
   /**
    * Method returns "1" for true, "0" for false.
    * 
    * @param b
    *          boolean value.
    * @return "1" for true, "0" for false.
    */
   private static String toString(final boolean b) {
     if (b) {
       return "1";
     } else {
       return "0";
     }
   }
 
   /**
    * Constructor.
    */
   public XcodeProjectWriter() {
   }
 
   /**
    * Adds a dependency to the object graph.
    * 
    * @param objects
    * @param project
    * @param mainGroupChildren
    * @param baseDir
    * @param dependency
    * @return PBXBuildFile to add to PBXFrameworksBuildPhase.
    */
   private PBXObjectRef addDependency(final Map objects, final PBXObjectRef project, final List mainGroupChildren,
       final String baseDir, final DependencyDef dependency) {
     if (dependency.getFile() != null) {
       final File xcodeDir = new File(dependency.getFile().getAbsolutePath() + ".xcodeproj");
       if (xcodeDir.exists()) {
         final PBXObjectRef xcodePrj = createPBXFileReference("SOURCE_ROOT", baseDir, xcodeDir);
         mainGroupChildren.add(xcodePrj);
         objects.put(xcodePrj.getID(), xcodePrj.getProperties());
 
         final int proxyType = 2;
         final PBXObjectRef proxy = createPBXContainerItemProxy(xcodePrj, proxyType, dependency.getName());
         objects.put(proxy.getID(), proxy.getProperties());
 
         final PBXObjectRef referenceProxy = createPBXReferenceProxy(proxy, dependency);
         objects.put(referenceProxy.getID(), referenceProxy.getProperties());
 
         final PBXObjectRef buildFile = createPBXBuildFile(referenceProxy, Collections.emptyMap());
         objects.put(buildFile.getID(), buildFile.getProperties());
 
         final List productsChildren = new ArrayList();
         productsChildren.add(referenceProxy);
         final PBXObjectRef products = createPBXGroup("Products", "<group>", productsChildren);
         objects.put(products.getID(), products.getProperties());
 
         final Map projectReference = new HashMap();
         projectReference.put("ProductGroup", products);
         projectReference.put("ProjectRef", xcodePrj);
 
         List projectReferences = (List) project.getProperties().get("ProjectReferences");
         if (projectReferences == null) {
           projectReferences = new ArrayList();
           project.getProperties().put("ProjectReferences", projectReferences);
         }
         projectReferences.add(projectReference);
         return buildFile;
       }
     }
     return null;
   }
 
   /**
    * Add documentation group to map of objects.
    * 
    * @param objects
    *          object map.
    * @param sourceTree
    *          source tree description.
    * @return documentation group.
    */
   private PBXObjectRef addDocumentationGroup(final Map objects, final String sourceTree) {
     final List productsList = new ArrayList();
     final PBXObjectRef products = createPBXGroup("Documentation", sourceTree, productsList);
     objects.put(products.getID(), products.getProperties());
     return products;
   }
 
   /**
    * Add native target to map of objects.
    * 
    * @param objects
    *          map of objects.
    * @param linkTarget
    *          description of executable or shared library.
    * @param product
    *          product.
    * @param projectName
    *          project name.
    * @param sourceGroupChildren
    *          source files needed to build product.
    * @return native target.
    */
   private PBXObjectRef addNativeTarget(final Map objects, final TargetInfo linkTarget, final PBXObjectRef product,
       final String projectName, final List<PBXObjectRef> sourceGroupChildren,
       final List<PBXObjectRef> frameworkBuildFiles) {
 
     final PBXObjectRef buildConfigurations = addNativeTargetConfigurationList(objects, projectName);
 
     int buildActionMask = 2147483647;
     final List<PBXObjectRef> buildPhases = new ArrayList<>();
 
     final Map settings = new HashMap();
     settings.put("ATTRIBUTES", new ArrayList());
     final List buildFiles = new ArrayList();
     for (final PBXObjectRef sourceFile : sourceGroupChildren) {
       final PBXObjectRef buildFile = createPBXBuildFile(sourceFile, settings);
       buildFiles.add(buildFile);
       objects.put(buildFile.getID(), buildFile.getProperties());
     }
 
     final PBXObjectRef sourcesBuildPhase = createPBXSourcesBuildPhase(buildActionMask, buildFiles, false);
     objects.put(sourcesBuildPhase.getID(), sourcesBuildPhase.getProperties());
     buildPhases.add(sourcesBuildPhase);
 
     buildActionMask = 8;
     final PBXObjectRef frameworksBuildPhase = createPBXFrameworksBuildPhase(buildActionMask, frameworkBuildFiles, false);
     objects.put(frameworksBuildPhase.getID(), frameworksBuildPhase.getProperties());
     buildPhases.add(frameworksBuildPhase);
 
     final PBXObjectRef copyFilesBuildPhase = createPBXCopyFilesBuildPhase(8, "/usr/share/man/man1", "0",
         new ArrayList(), true);
     objects.put(copyFilesBuildPhase.getID(), copyFilesBuildPhase.getProperties());
     buildPhases.add(copyFilesBuildPhase);
 
     final List buildRules = new ArrayList();
 
     final List dependencies = new ArrayList();
 
     final String productInstallPath = "$(HOME)/bin";
 
     final String productType = getProductType(linkTarget);
 
     final PBXObjectRef nativeTarget = createPBXNativeTarget(projectName, buildConfigurations, buildPhases, buildRules,
         dependencies, productInstallPath, projectName, product, productType);
     objects.put(nativeTarget.getID(), nativeTarget.getProperties());
 
     return nativeTarget;
   }
 
   /**
    * Add native target configuration list.
    * 
    * @param objects
    *          map of objects.
    * @param projectName
    *          project name.
    * @return build configurations for native target.
    */
   private PBXObjectRef addNativeTargetConfigurationList(final Map objects, final String projectName) {
 
     //
     // Create a configuration list with
     // two stock configurations: Debug and Release
     //
     final List<PBXObjectRef> configurations = new ArrayList<>();
     final Map debugSettings = new HashMap();
     debugSettings.put("COPY_PHASE_STRIP", "NO");
     debugSettings.put("GCC_DYNAMIC_NO_PIC", "NO");
     debugSettings.put("GCC_ENABLE_FIX_AND_CONTINUE", "YES");
     debugSettings.put("GCC_MODEL_TUNING", "G5");
     debugSettings.put("GCC_OPTIMIZATION_LEVEL", "0");
     debugSettings.put("INSTALL_PATH", "$(HOME)/bin");
     debugSettings.put("PRODUCT_NAME", projectName);
     debugSettings.put("ZERO_LINK", "YES");
     final PBXObjectRef debugConfig = createXCBuildConfiguration("Debug", debugSettings);
     objects.put(debugConfig.getID(), debugConfig.getProperties());
     configurations.add(debugConfig);
 
     final Map<String, Object> releaseSettings = new HashMap<>();
     final List<String> archs = new ArrayList<>();
     archs.add("ppc");
     archs.add("i386");
     releaseSettings.put("ARCHS", archs);
     releaseSettings.put("GCC_GENERATE_DEBUGGING_SYMBOLS", "NO");
     releaseSettings.put("GCC_MODEL_TUNING", "G5");
     releaseSettings.put("INSTALL_PATH", "$(HOME)/bin");
     releaseSettings.put("PRODUCT_NAME", projectName);
     final PBXObjectRef releaseConfig = createXCBuildConfiguration("Release", releaseSettings);
     objects.put(releaseConfig.getID(), releaseConfig.getProperties());
     configurations.add(releaseConfig);
 
     final PBXObjectRef configurationList = createXCConfigurationList(configurations);
     objects.put(configurationList.getID(), configurationList.getProperties());
     return configurationList;
   }
 
   /**
    * Add file reference of product to map of objects.
    * 
    * @param objects
    *          object map.
    * @param linkTarget
    *          build description for executable or shared library.
    * @return file reference to generated executable or shared library.
    */
   private PBXObjectRef addProduct(final Map objects, final TargetInfo linkTarget) {
 
     //
     // create file reference for executable file
     // forget Ant's location, just place in XCode's default location
     final PBXObjectRef executable = createPBXFileReference("BUILD_PRODUCTS_DIR", linkTarget.getOutput().getParent(),
         linkTarget.getOutput());
     final Map executableProperties = executable.getProperties();
 
     final String fileType = getFileType(linkTarget);
     executableProperties.put("explicitFileType", fileType);
     executableProperties.put("includeInIndex", "0");
     objects.put(executable.getID(), executableProperties);
 
     return executable;
   }
 
   /**
    * Add project configuration list.
    * 
    * @param objects
    *          map of objects.
    * @param baseDir
    *          base directory.
    * @param compilerConfig
    *          compiler configuration.
    * @return project configuration object.
    */
   private PBXObjectRef addProjectConfigurationList(final Map objects, final String baseDir,
       final List<DependencyDef> dependencies, final CommandLineCompilerConfiguration compilerConfig,
       final CommandLineLinkerConfiguration linkerConfig) {
     //
     // Create a configuration list with
     // two stock configurations: Debug and Release
     //
     final List configurations = new ArrayList();
     final Map<String, Object> debugSettings = new HashMap<>();
     debugSettings.put("GCC_WARN_ABOUT_RETURN_TYPE", "YES");
     debugSettings.put("GCC_WARN_UNUSED_VARIABLE", "YES");
     debugSettings.put("PREBINDING", "NO");
     debugSettings.put("SDKROOT", "/Developer/SDKs/MacOSX10.4u.sdk");
 
     final PBXObjectRef debugConfig = createXCBuildConfiguration("Debug", debugSettings);
     objects.put(debugConfig.getID(), debugConfig.getProperties());
     configurations.add(debugConfig);
 
     final Map<String, Object> releaseSettings = new HashMap<>();
     releaseSettings.put("GCC_WARN_ABOUT_RETURN_TYPE", "YES");
     releaseSettings.put("GCC_WARN_UNUSED_VARIABLE", "YES");
     releaseSettings.put("PREBINDING", "NO");
     releaseSettings.put("SDKROOT", "/Developer/SDKs/MacOSX10.4u.sdk");
     final PBXObjectRef releaseConfig = createXCBuildConfiguration("Release", releaseSettings);
     objects.put(releaseConfig.getID(), releaseConfig.getProperties());
     configurations.add(releaseConfig);
     final PBXObjectRef configurationList = createXCConfigurationList(configurations);
     final Map projectConfigurationListProperties = configurationList.getProperties();
     projectConfigurationListProperties.put("defaultConfigurationIsVisible", "0");
     projectConfigurationListProperties.put("defaultConfigurationName", "Debug");
     objects.put(configurationList.getID(), configurationList.getProperties());
 
     //
     // add include paths to both configurations
     //
     final File[] includeDirs = compilerConfig.getIncludePath();
     if (includeDirs.length > 0) {
       final List<String> includePaths = new ArrayList<>();
       final Map<String, String> includePathMap = new HashMap<>();
       for (final File includeDir : includeDirs) {
         if (!CUtil.isSystemPath(includeDir)) {
           final String absPath = includeDir.getAbsolutePath();
           if (!includePathMap.containsKey(absPath)) {
             if (absPath.startsWith("/usr/")) {
               includePaths.add(CUtil.toUnixPath(absPath));
             } else {
               final String relPath = CUtil.toUnixPath(CUtil.getRelativePath(baseDir, includeDir));
               includePaths.add(relPath);
             }
             includePathMap.put(absPath, absPath);
           }
         }
       }
       includePaths.add("${inherited)");
       debugSettings.put("HEADER_SEARCH_PATHS", includePaths);
       releaseSettings.put("HEADER_SEARCH_PATHS", includePaths);
     }
 
     //
     // add preprocessor definitions to both configurations
     //
     //
     final String[] preArgs = compilerConfig.getPreArguments();
     final List<String> defines = new ArrayList<>();
     for (final String preArg : preArgs) {
       if (preArg.startsWith("-D")) {
         defines.add(preArg.substring(2));
       }
     }
     if (defines.size() > 0) {
       defines.add("$(inherited)");
       debugSettings.put("GCC_PREPROCESSOR_DEFINITIONS", defines);
       releaseSettings.put("GCC_PREPROCESSOR_DEFINITIONS", defines);
     }
 
     if (linkerConfig != null) {
       final Map<String, String> librarySearchMap = new HashMap<>();
       final List<String> librarySearchPaths = new ArrayList<>();
       final List<String> otherLdFlags = new ArrayList<>();
       final String[] linkerArgs = linkerConfig.getEndArguments();
       for (final String linkerArg : linkerArgs) {
         if (linkerArg.startsWith("-L")) {
           final String libDir = linkerArg.substring(2);
           if (!librarySearchMap.containsKey(libDir)) {
             if (!libDir.equals("/usr/lib")) {
               librarySearchPaths.add(CUtil.toUnixPath(CUtil.getRelativePath(baseDir, new File(libDir))));
             }
             librarySearchMap.put(libDir, libDir);
 
           }
         } else if (linkerArg.startsWith("-l")) {
           //
           // check if library is in dependencies list
           //
           final String libName = linkerArg.substring(2);
           boolean found = false;
           for (final DependencyDef dependency : dependencies) {
             if (libName.startsWith(dependency.getName())) {
               final File dependencyFile = dependency.getFile();
               if (dependencyFile != null && new File(dependencyFile.getAbsolutePath() + ".xcodeproj").exists()) {
                 found = true;
                 break;
               }
             }
           }
           if (!found) {
             otherLdFlags.add(linkerArg);
           }
         }
       }
 
       debugSettings.put("LIBRARY_SEARCH_PATHS", librarySearchPaths);
       debugSettings.put("OTHER_LDFLAGS", otherLdFlags);
       releaseSettings.put("LIBRARY_SEARCH_PATHS", librarySearchPaths);
       releaseSettings.put("OTHER_LDFLAGS", otherLdFlags);
     }
     return configurationList;
   }
 
   /**
    * Add file references for all source files to map of objects.
    * 
    * @param objects
    *          map of objects.
    * @param sourceTree
    *          source tree.
    * @param basePath
    *          parent of XCode project dir
    * @param targets
    *          build targets.
    * @return list containing file references of source files.
    */
   private List<PBXObjectRef> addSources(final Map objects, final String sourceTree, final String basePath,
       final Map<String, TargetInfo> targets) {
     final List<PBXObjectRef> sourceGroupChildren = new ArrayList<>();
 
     final List<File> sourceList = new ArrayList<>(targets.size());
     for (final TargetInfo info : targets.values()) {
       final File[] targetsources = info.getSources();
       Collections.addAll(sourceList, targetsources);
     }
     final File[] sortedSources = sourceList.toArray(new File[sourceList.size()]);
     Arrays.sort(sortedSources, new Comparator<File>() {
       @Override
       public int compare(final File o1, final File o2) {
         return o1.getName().compareTo(o2.getName());
       }
     });
     for (final File sortedSource : sortedSources) {
       final PBXObjectRef fileRef = createPBXFileReference(sourceTree, basePath, sortedSource);
       sourceGroupChildren.add(fileRef);
       objects.put(fileRef.getID(), fileRef.getProperties());
     }
 
     return sourceGroupChildren;
   }
 
   /**
    * Gets the first recognized compiler from the
    * compilation targets.
    *
    * @param targets
    *          compilation targets
    * @return representative (hopefully) compiler configuration
    */
   private CommandLineCompilerConfiguration getBaseCompilerConfiguration(final Map targets) {
     //
     // find first target with an GNU C++ compilation
     //
     CommandLineCompilerConfiguration compilerConfig;
     //
     // get the first target and assume that it is representative
     //
     for (final Object o : targets.values()) {
       final TargetInfo targetInfo = (TargetInfo) o;
       final ProcessorConfiguration config = targetInfo.getConfiguration();
       //
       // for the first cl compiler
       //
       if (config instanceof CommandLineCompilerConfiguration) {
         compilerConfig = (CommandLineCompilerConfiguration) config;
         if (compilerConfig.getCompiler() instanceof GccCCompiler) {
           return compilerConfig;
         }
       }
     }
     return null;
   }
 
   private String getFileType(final TargetInfo linkTarget) {
     switch (getProductTypeIndex(linkTarget)) {
       case 1:
         return "archive.ar";
       case 2:
         return "compiled.mach-o.dylib";
       default:
         return "compiled.mach-o.executable";
     }
   }
 
   private String getProductType(final TargetInfo linkTarget) {
     switch (getProductTypeIndex(linkTarget)) {
       case 1:
         return "com.apple.product-type.library.static";
       case 2:
         return "com.apple.product-type.library.dynamic";
       default:
         return "com.apple.product-type.tool";
     }
   }
 
   private int getProductTypeIndex(final TargetInfo linkTarget) {
     final String outPath = linkTarget.getOutput().getPath();
     String outExtension = null;
     final int lastDot = outPath.lastIndexOf('.');
     if (lastDot != -1) {
       outExtension = outPath.substring(lastDot);
     }
     if (".a".equalsIgnoreCase(outExtension) || ".lib".equalsIgnoreCase(outExtension)) {
       return 1;
     } else if (".dylib".equalsIgnoreCase(outExtension) || ".so".equalsIgnoreCase(outExtension)
         || ".dll".equalsIgnoreCase(outExtension)) {
       return 2;
     }
     return 0;
   }
 
   /**
    * Writes a project definition file.
    *
    * @param fileName
    *          File name base, writer may append appropriate extension
    * @param task
    *          cc task for which to write project
    * @param projectDef
    *          project element
    * @param targets
    *          compilation targets
    * @param linkTarget
    *          link target
    * @throws IOException
    *           if error writing project file
    */
   @Override
   public void writeProject(final File fileName, final CCTask task, final ProjectDef projectDef,
       final List<File> sources, final Map<String, TargetInfo> targets, final TargetInfo linkTarget) throws IOException {
 
     final File xcodeDir = new File(fileName + ".xcodeproj");
     if (!projectDef.getOverwrite() && xcodeDir.exists()) {
       throw new BuildException("Not allowed to overwrite project file " + xcodeDir.toString());
     }
 
     final CommandLineCompilerConfiguration compilerConfig = getBaseCompilerConfiguration(targets);
     if (compilerConfig == null) {
       throw new BuildException("Unable to find compilation target using GNU C++ compiler");
     }
 
     CommandLineLinkerConfiguration linkerConfig = null;
     if (linkTarget.getConfiguration() instanceof CommandLineLinkerConfiguration) {
       linkerConfig = (CommandLineLinkerConfiguration) linkTarget.getConfiguration();
     }
 
     String projectName = projectDef.getName();
     if (projectName == null) {
       projectName = fileName.getName();
     }
     final String basePath = fileName.getAbsoluteFile().getParent();
 
     xcodeDir.mkdir();
 
     final File xcodeProj = new File(xcodeDir, "project.pbxproj");
 
     //
     // create property list
     //
     final Map<String, Object> propertyList = new HashMap<>();
     propertyList.put("archiveVersion", "1");
     propertyList.put("classes", new HashMap());
     propertyList.put("objectVersion", "42");
     final Map objects = new HashMap();
 
     final String sourceTree = "<source>";
 
     //
     // add source files and source group to property list
     //
     final List<PBXObjectRef> sourceGroupChildren = addSources(objects, "SOURCE_ROOT", basePath, targets);
     final PBXObjectRef sourceGroup = createPBXGroup("Source", sourceTree, sourceGroupChildren);
     objects.put(sourceGroup.getID(), sourceGroup.getProperties());
 
     //
     // add product to property list
     //
     final PBXObjectRef product = addProduct(objects, linkTarget);
     final List<PBXObjectRef> productsList = new ArrayList<>();
     productsList.add(product);
     final PBXObjectRef productsGroup = createPBXGroup("Products", sourceTree, productsList);
     objects.put(productsGroup.getID(), productsGroup.getProperties());
 
     //
     // add documentation group to property list
     //
     final PBXObjectRef documentationGroup = addDocumentationGroup(objects, sourceTree);
 
     //
     // add main group containing source, products and documentation group
     //
     final List<PBXObjectRef> groups = new ArrayList<>(3);
     groups.add(sourceGroup);
     groups.add(documentationGroup);
     groups.add(productsGroup);
     final PBXObjectRef mainGroup = createPBXGroup(projectName, sourceTree, groups);
     final StringBuffer comments = new StringBuffer();
     for (final CommentDef commentDef : projectDef.getComments()) {
       comments.append(commentDef);
     }
     if (comments.length() > 0) {
       mainGroup.getProperties().put("comments", comments.toString());
     }
     objects.put(mainGroup.getID(), mainGroup.getProperties());
 
     //
     // add project configurations
     //
     final PBXObjectRef compilerConfigurations = addProjectConfigurationList(objects, basePath,
         projectDef.getDependencies(), compilerConfig, linkerConfig);
 
     final String projectDirPath = "";
     final List<PBXObjectRef> projectTargets = new ArrayList<>();
 
     //
     // add project to property list
     //
     //
     // Calculate path (typically several ../..) of the root directory
     // (where build.xml lives) relative to the XCode project directory.
     // XCode 3.0 will now prompt user to supply the value if not specified.
     final String projectRoot = CUtil.toUnixPath(CUtil.getRelativePath(basePath, projectDef.getProject().getBaseDir()));
     final PBXObjectRef project = createPBXProject(compilerConfigurations, mainGroup, projectDirPath, projectRoot,
         projectTargets);
     objects.put(project.getID(), project.getProperties());
 
     final List<PBXObjectRef> frameworkBuildFiles = new ArrayList<>();
     for (final DependencyDef dependency : projectDef.getDependencies()) {
       final PBXObjectRef buildFile = addDependency(objects, project, groups, basePath, dependency);
       if (buildFile != null) {
         frameworkBuildFiles.add(buildFile);
       }
     }
     //
     // add description of native target (that is the executable or
     // shared library)
     //
     final PBXObjectRef nativeTarget = addNativeTarget(objects, linkTarget, product, projectName, sourceGroupChildren,
         frameworkBuildFiles);
     projectTargets.add(nativeTarget);
 
     //
     // finish up overall property list
     //
     propertyList.put("objects", objects);
     propertyList.put("rootObject", project.getID());
 
     //
     // write property list out to XML file
     //
     try {
       PropertyListSerialization.serialize(propertyList, projectDef.getComments(), xcodeProj);
     } catch (final TransformerConfigurationException ex) {
       throw new IOException(ex.toString());
     } catch (final SAXException ex) {
       if (ex.getException() instanceof IOException) {
         throw (IOException) ex.getException();
       }
       throw new IOException(ex.toString());
     }
   }
 
 }