/**
   * Returns the implementation type (REST, Bean, Mock, etc) of every services bootstrap module
   * listed at [appCode].client.properties.xml file to do so, it scans the packages under {core
   * appCode}.internal for types implementing {@link ServicesCoreBootstrapGuiceModule}
   *
   * <p>Some times a services implementation NEEDS (or DEPENDS UPON) another service implementation,
   * for example, the REST services implementation NEEDS the Bean services implementation because
   * REST services is only an ACCESS LAYER on top of the Bean services layer that is where the real
   * services logic resides.
   *
   * @return
   */
  public Map<CoreAppAndModule, Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>>
      findBootstrapGuiceModuleTypes() {
    if (_coreAppAndModules == null) return Maps.newHashMap(); // do not return a null config

    Map<CoreAppAndModule, Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>>
        outModuleTypes = Maps.newHashMap();

    // Iterate over all the app/module collection (each app/module can have many
    // ServicesCoreGuiceModules, ie: REST, Bean, etc.. one of them is the DEFAULT one)
    // NOTE: If more than one implementation is found, the BEAN has the highest priority followed by
    // the REST implementation
    //
    // for each app/module
    //		1.- Find the available ServicesCoreGuiceModules
    //		2.- For each found module found, try to find the needed modules
    //			(sometimes a module (ie REST) NEEDS another modules (ie Bean or EJB) to do delegate the
    // work)
    //			... this task is a bit tricky since the order in which the modules are found is important
    //		    ... the checking of the presence of needed modules MUST be done AFTER all modules are
    // processed

    // Find guice modules implementing ServicesCoreGuiceModule either
    // BeanImplementedServicesGuiceModuleBase, RESTImplementedServicesGuiceModuleBase,
    // EJBImplementedServicesGuiceModuleBase, etc)
    Map<CoreAppAndModule, Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>>
        coreBootstrapModuleTypesByApp =
            _findCoreBootstrapGuiceModuleTypesByAppModule(_coreAppAndModules);

    Collection<BootstrapModuleDependency> dependencies = Lists.newArrayList();
    for (CoreAppAndModule coreAppModule : _coreAppAndModules) {

      CoreAppCode coreAppCode = coreAppModule.getAppCode();
      CoreModule module = coreAppModule.getModule();

      // [1] - Get the modules for the appCode
      Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>
          appModuleCoreBootstrapModuleTypes = coreBootstrapModuleTypesByApp.get(coreAppModule);
      if (appModuleCoreBootstrapModuleTypes == null) {
        log.warn(
            "\t\t-{} core will NOT be bootstraped: There's NO type implementing {} at package {} or the {} package is NOT in the classpath. "
                + "If the {} core is to be bootstraped there MUST be AT LEAST a guice binding module extending {} at {} ",
            coreAppModule,
            ServicesCoreBootstrapGuiceModule.class,
            ServicesPackages.coreGuiceModulePackage(coreAppCode),
            ServicesPackages.coreGuiceModulePackage(coreAppCode),
            coreAppModule,
            ServicesCoreBootstrapGuiceModule.class,
            ServicesPackages.coreGuiceModulePackage(coreAppCode));
        continue;
      }
      log.warn(
          "\t\t-{} core will be bootstraped with: {}",
          coreAppModule,
          coreBootstrapModuleTypesByApp.get(coreAppModule));

      // [2] - for each found core bootstrap module try to find the needed modules (ie REST
      // bootstrap modules depends on BEAN bootstrap modules)
      for (Class<? extends ServicesCoreBootstrapGuiceModule> foundModuleType :
          appModuleCoreBootstrapModuleTypes) {
        if (ReflectionUtils.isInterface(foundModuleType)) continue;

        // Check if there's any module dependency set at @ServicesCore annotation
        ServicesCore servicesCoreAnnot =
            ReflectionUtils.typeAnnotation(foundModuleType, ServicesCore.class);

        // find the needed impl (the ServicesGuiceModule-implementing type MUST be annotated with
        // ServicesGuiceModuleDependencies)
        // (sometimes a service impl requires of another service impl, for example, REST services
        // USES Bean services)
        if (!CollectionUtils.of(servicesCoreAnnot.dependsOn()).contains(ServicesImpl.NULL)) {
          CoreAppAndModule ac =
              Strings.isNullOrEmpty(servicesCoreAnnot.fromOtherCoreAppCodeAndModule())
                  ? coreAppModule // by default dependencies are at the same coreAppCode/module
                  : CoreAppAndModule.of(servicesCoreAnnot.fromOtherCoreAppCodeAndModule());
          Collection<ServicesImpl> impls = Arrays.asList(servicesCoreAnnot.dependsOn());
          BootstrapModuleDependency dependency =
              new BootstrapModuleDependency(coreAppModule, foundModuleType, ac, impls);
          dependencies.add(dependency);
          log.warn(
              "\t\t\t- Found {} CORE services bootstrap module (it has a dependency on other core component {}): {}",
              foundModuleType,
              dependency.debugInfo());
        } else {
          log.warn(
              "\t\t\t- Found {} CORE services bootstrap module (no other bootstrap type dependency)",
              foundModuleType);
        }
      } // for bindingModules

      // [3] - put the core bootstrap modules in the output collection indexed by the
      // appCode/component
      outModuleTypes.put(coreAppModule, appModuleCoreBootstrapModuleTypes);
    } // for configuredBindingModules

    // Finally, make sure that the dependencies are satisfied
    if (CollectionUtils.hasData(dependencies)) {
      for (BootstrapModuleDependency dependency : dependencies) {
        Collection<Class<? extends ServicesCoreBootstrapGuiceModule>> otherCoreMods =
            outModuleTypes.get(dependency.getOtherAppAndComponent());

        for (ServicesImpl depImpl : dependency.getDependencies()) {
          boolean isLoaded = false;
          if (CollectionUtils.hasData(otherCoreMods)) {
            for (Class<? extends ServicesCoreBootstrapGuiceModule> otherCoreMod : otherCoreMods) {
              if (ServicesImpl.fromBindingModule(otherCoreMod) == depImpl) {
                isLoaded = true;
                break;
              }
            }
          }
          if (!isLoaded)
            throw new IllegalStateException(
                Strings.customized(
                    "{} (see @{})."
                        + "BUT this module could NOT be loaded."
                        + "Please ensure that a {} annotated type with impl={} attribute is accesible in the run-time classpath (maybe de dependent project is NOT deployed and available at the classpath)",
                    dependency.debugInfo(),
                    ServicesCore.class.getSimpleName(),
                    ServicesCoreBootstrapGuiceModule.class,
                    depImpl));
        }
      }
    }

    // Return
    return outModuleTypes;
  }
  /**
   * Finds types extending {@link ServicesCoreBootstrapGuiceModule}: {@link
   * BeanImplementedServicesCoreGuiceModule}, {@link RESTImplementedServicesCoreGuiceModuleBase},
   * etc and returns them indexed by appCode / component
   *
   * @param coreAppCode
   * @param coreModule
   * @return
   */
  private Map<CoreAppAndModule, Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>>
      _findCoreBootstrapGuiceModuleTypesByAppModule(
          final Collection<CoreAppAndModule> coreAppAndComponents) {
    // get the core appcodes from the collection of core appCode/module
    Collection<CoreAppCode> coreAppCodes =
        FluentIterable.from(coreAppAndComponents)
            .transform(
                new Function<CoreAppAndModule, CoreAppCode>() {
                  @Override
                  public CoreAppCode apply(final CoreAppAndModule appAndComponent) {
                    return appAndComponent.getAppCode();
                  }
                })
            .toSet();

    // Find the types implementing ServicesCoreGuiceModule at all the core appcodes (ie: r01t,
    // aa14b, aa81b, etc)
    Set<Class<? extends ServicesCoreBootstrapGuiceModule>> foundBootstrapModuleTypes =
        _findCoreGuiceModulesOrNull(coreAppCodes, ServicesCoreBootstrapGuiceModule.class);

    // Group the found core bootstrap module types by appCode/module
    Map<CoreAppAndModule, Collection<Class<? extends ServicesCoreBootstrapGuiceModule>>>
        outCoreModules = null;
    if (CollectionUtils.hasData(foundBootstrapModuleTypes)) {

      outCoreModules = Maps.newHashMapWithExpectedSize(coreAppCodes.size());
      for (Class<? extends ServicesCoreBootstrapGuiceModule> bootstrapModuleType :
          foundBootstrapModuleTypes) {

        // get type appCode from the bootstrap module type's package (ie: r01t.internal.XXX) and
        // it's @ServiceCore annotation
        CoreAppCode appCode =
            ServicesPackages.appCodeFromCoreBootstrapModuleType(
                bootstrapModuleType); // use the service's core bootstrap type's package to get the
                                      // appCode
        CoreModule coreModule =
            ServicesPackages.appComponentFromCoreBootstrapModuleTypeOrThrow(
                bootstrapModuleType); // use the service's @ServicesCore annotation to get the
                                      // module
        CoreAppAndModule coreAppAndModule = CoreAppAndModule.of(appCode, coreModule);

        Collection<Class<? extends ServicesCoreBootstrapGuiceModule>> appModuleTypes =
            outCoreModules.get(coreAppAndModule);
        if (appModuleTypes == null) {
          appModuleTypes = Sets.newHashSet();
          outCoreModules.put(coreAppAndModule, appModuleTypes);
        }
        appModuleTypes.add(bootstrapModuleType);
      }
    } else {
      log.warn(
          "There's NO type implementing {} in the classpath! For the CORE app codes {}, there MUST be AT LEAST a guice binding module extending {} at package {}",
          ServicesCoreBootstrapGuiceModule.class.getSimpleName(),
          coreAppCodes,
          ServicesCoreBootstrapGuiceModule.class,
          ServicesPackages.coreGuiceModulePackage(CoreAppCode.forId("[coreAppCode]")),
          ServicesCoreBootstrapGuiceModule.class);
      outCoreModules = Maps.newHashMap();
    }
    return outCoreModules;
  }