/**

  * - Digitalis Internal Framework v2.0 - (C) 2007, Digitalis Informatica. Distribuicao e Gestao de Informatica, Lda.

  * Estrada de Paco de Arcos num.9 - Piso -1 2780-666 Paco de Arcos Telefone: (351) 21 4408990 Fax: (351) 21 4408999

  * http://www.digitalis.pt

  */

 package pt.digitalis.dif.startup;

 import java.util.Collections;

 import java.util.Comparator;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Stack;

 import pt.digitalis.dif.codegen.DIFCodeGenerator;

 import pt.digitalis.dif.controller.interfaces.IModelManager;

 import pt.digitalis.dif.controller.security.managers.IAuthenticationManager;

 import pt.digitalis.dif.controller.security.managers.IIdentityManager;

 import pt.digitalis.dif.controller.security.managers.impl.IdentityManagerStaticImpl;

 import pt.digitalis.dif.dem.interfaces.IApplication;

 import pt.digitalis.dif.dem.interfaces.IApplicationConfiguration;

 import pt.digitalis.dif.dem.interfaces.IApplicationPrivate;

 import pt.digitalis.dif.dem.interfaces.IDIFAPI;

 import pt.digitalis.dif.dem.interfaces.IProvider;

 import pt.digitalis.dif.dem.interfaces.IService;

 import pt.digitalis.dif.dem.interfaces.IStage;

 import pt.digitalis.dif.dem.managers.IDEMManager;

 import pt.digitalis.dif.dem.managers.impl.UsageIssuesManagerImpl;

 import pt.digitalis.dif.dem.objects.issues.UsageIssue;

 import pt.digitalis.dif.exception.InternalFrameworkException;

 import pt.digitalis.dif.exception.codegen.DIFCodeGenerationException;

 import pt.digitalis.dif.ioc.DIFIoCRegistry;

 import pt.digitalis.dif.utils.logging.DIFLogger;

 import pt.digitalis.log.LogLevel;

 import pt.digitalis.utils.bytecode.exceptions.CodeGenerationException;

 import pt.digitalis.utils.inspection.exception.ResourceNotFoundException;

 import pt.digitalis.utils.ioc.IIoCRegistry;

 /**

  * This class contains the initialization logic to set the framework ready to serve requests. Listeners must check if

  * the framework is ready to serve the request before submitting a new request for service.

  * 

  * @author Pedro Viegas <a href="mailto:pviegas@digitalis.pt">pviegas@digitalis.pt</a>

  * @author Rodrigo Gonçalves <a href="mailto:rgoncalves@digitalis.pt">rgoncalves@digitalis.pt</a>

  * @created Oct 8, 2007

  */

 final public class DIFInitializer {

     /** The indentation character. */

     final static private String INDENTATION = "  ";

     /** Initialization state. */

     static private boolean initialized = false;

     /**

      * Adds the issues of a given location to the buffer.

      * 

      * @param location

      *            the location

      * @param buffer

      *            the buffer

      * @param indentPrefix

      *            the indentation prefix string or output

      */

     static private void addIssuesToBuffer(String location, StringBuffer buffer, String indentPrefix)

     {

         // Reuse var

         List<UsageIssue> issues = null;

         issues = UsageIssuesManagerImpl.getInstance().getIssues(location);

         for (UsageIssue usageIssue: issues)

             buffer.append(indentPrefix + "  => " + usageIssue.getIssueType() + ": " + usageIssue.getIssueDescription()

                     + "\n");

     }

     /**

      * Dumps the DEM.

      */

     static private void dumpDEM()

     {

         // When in debug dump the full DEM structure to the log.

         StringBuffer buffer = new StringBuffer();

         Stack<String> indentationsStack = new Stack<String>();

         String currentIndentation = null;

         buffer.append("\n\nDumping DEM structure:\n");

         buffer.append("-----------------------------------------\n");

         IDEMManager dem = DIFIoCRegistry.getRegistry().getImplementation(IDEMManager.class);

         Iterator<IProvider> providers = dem.getProviders().values().iterator();

         while (providers.hasNext())

         {

             IProvider provider = providers.next();

             if (providers.hasNext())

             {

                 currentIndentation = INDENTATION + "|   ";

                 buffer.append(INDENTATION + "|-- Provider: " + provider.getName() + " (" + provider.getID() + ")\n");

             }

             else

             {

                 currentIndentation = INDENTATION + "    ";

                 buffer.append(INDENTATION + "`-- Provider: " + provider.getName() + " (" + provider.getID() + ")\n");

             }

             if (UsageIssuesManagerImpl.getInstance().hasIssues(provider.getOriginalClassName()))

                 addIssuesToBuffer(provider.getOriginalClassName(), buffer, currentIndentation);

             // Applications iteration

             Iterator<IApplication> applications = provider.getApplications().values().iterator();

             while (applications.hasNext())

             {

                 IApplication application = applications.next();

                 indentationsStack.add(currentIndentation);

                 if (applications.hasNext())

                 {

                     buffer.append(currentIndentation + INDENTATION + "|-- Application: " + application.getName() + " ("

                             + application.getID() + ")\n");

                     currentIndentation += INDENTATION + "|   ";

                 }

                 else

                 {

                     buffer.append(currentIndentation + INDENTATION + "`-- Application: " + application.getName() + " ("

                             + application.getID() + ")\n");

                     currentIndentation += INDENTATION + "    ";

                 }

                 if (UsageIssuesManagerImpl.getInstance().hasIssues(application.getOriginalClassName()))

                     addIssuesToBuffer(application.getOriginalClassName(), buffer, currentIndentation);

                 // Services iteration

                 Iterator<IService> services = application.getServices().values().iterator();

                 while (services.hasNext())

                 {

                     IService service = services.next();

                     indentationsStack.add(currentIndentation);

                     if (services.hasNext())

                     {

                         buffer.append(currentIndentation + INDENTATION + "|-- Service: " + service.getName() + " ("

                                 + service.getID() + ")\n");

                         currentIndentation += INDENTATION + "|   ";

                     }

                     else

                     {

                         buffer.append(currentIndentation + INDENTATION + "`-- Service: " + service.getName() + " ("

                                 + service.getID() + ")\n");

                         currentIndentation += INDENTATION + "    ";

                     }

                     if (UsageIssuesManagerImpl.getInstance().hasIssues(service.getOriginalClassName()))

                         addIssuesToBuffer(service.getOriginalClassName(), buffer, currentIndentation);

                     // Stages iteration

                     Iterator<IStage> stages = service.getStages().values().iterator();

                     while (stages.hasNext())

                     {

                         IStage stage = stages.next();

                         indentationsStack.add(currentIndentation);

                         if (stages.hasNext())

                         {

                             buffer.append(currentIndentation + INDENTATION + "|-- " + stage.getName() + " ("

                                     + stage.getID() + ")\n");

                             currentIndentation += INDENTATION + "|   ";

                         }

                         else

                         {

                             buffer.append(currentIndentation + INDENTATION + "`-- " + stage.getName() + " ("

                                     + stage.getID() + ")\n");

                             currentIndentation += INDENTATION + "    ";

                         }

                         if (UsageIssuesManagerImpl.getInstance().hasIssues(stage.getOriginalClassName()))

                             addIssuesToBuffer(stage.getOriginalClassName(), buffer, currentIndentation);

                         currentIndentation = indentationsStack.pop();

                     }

                     buffer.append(currentIndentation + "\n");

                     currentIndentation = indentationsStack.pop();

                 }

                 currentIndentation = indentationsStack.pop();

             }

         }

         buffer.append("-----------------------------------------\n\n");

         if (DIFStartupConfiguration.getLogLevel().equals(LogLevel.DEBUG))

             DIFLogger.getLogger().debug(buffer.toString());

         else

             DIFLogger.getLogger().info(buffer.toString());

     }

     /**

      * DIF initialization method. Defines the order of the initialization steps.

      * 

      * @param initDEMInstances

      *            if T searches for DEM instances and initializes then

      * @param upgradeModelManagers

      *            if T upgrades all Model Manager contributions

      * @return T if initialization has successfully completed (or if has been previously done), F otherwise

      */

     synchronized static public boolean initialize(boolean initDEMInstances, boolean upgradeModelManagers)

     {

         if (!isInitialized())

         {

             try

             {

                 // IoC initialization (includes module discovery)

                 IIoCRegistry iocRegistry = DIFIoCRegistry.getRegistry();

                 // Startup the Identity and Authorization since they will be called form the CG process of the DEM

                 iocRegistry.getImplementation(IIdentityManager.class);

                 iocRegistry.getImplementation(IAuthenticationManager.class);

                 /*

                  * ATTENTION !!! ......................................................................................

                  * The model upgrade must be before all things, mainly because:........................................

                  * - code generation may need to invoke identity manager ..............................................

                  * - application init usually initializes all models ..................................................

                  */

                 if (upgradeModelManagers)

                 {

                     // Upgrades all database model, declared to the current application

                     DIFLogger.getLogger().info("Initializing Model Manager upgrades...");

                     DIFLogger.getLogger().increaseIndentation();

                     for (IModelManager modelManager: DIFIoCRegistry.getRegistry().getImplementations(

                             IModelManager.class))

                     {

                         if (modelManager.isEnabled())

                         {

                             if (!modelManager.isUpToDate())

                             {

                                 String currentVersion = modelManager.getCurrentVersion();

                                 DIFLogger.getLogger().info(

                                         "Model '" + modelManager.getSchema() + "': Upgrading from " + currentVersion);

                                 modelManager.updateVersion();

                                 DIFLogger.getLogger().info(

                                         "Model '" + modelManager.getSchema() + "': Upgraded to "

                                                 + modelManager.getCurrentVersion());

                             }

                             else

                             {

                                 DIFLogger.getLogger().info("Model '" + modelManager.getSchema() + "': Up to date");

                             }

                         }

                     }

                     DIFLogger.getLogger().decreaseIndentation();

                 }

                 // Create the DIF code generator and inject it's dependencies into it

                 DIFCodeGenerator codeGen = new DIFCodeGenerator();

                 iocRegistry.injectDependencies(codeGen);

                 if (initDEMInstances)

                 {

                     // Discover all registered DEM entities packages

                     codeGen.collectRegisteredPackages();

                     // Search registered entities

                     codeGen.searchRegisteredPackages();

                     // Enhance the registered entities

                     codeGen.enhanceDEMClasses();

                 }

                 // Log all issues if in debug

                 if (DIFStartupConfiguration.getLogLevel().equals(LogLevel.DEBUG))

                     UsageIssuesManagerImpl.getInstance().logAllIssuesByType();

                 // Clean up all temporary data

                 codeGen.cleanUp();

                 // Initialize the declared APIs

                 initializeAPIs();

                 // Run the applications initialization procedures

                 initializeApplications();

                 // If the identityManager is the static implementation, call the static users initialization

                 IIdentityManager identityManager = DIFIoCRegistry.getRegistry().getImplementation(

                         IIdentityManager.class);

                 if (identityManager instanceof IdentityManagerStaticImpl)

                     ((IdentityManagerStaticImpl) identityManager).initializeStaticCustomUsers();

                 initialized = true;

                 // Dump DEM structure with associated issues (if any), if DiF is running in DEBUG mode or if there are

                 // issues

                 if (DIFStartupConfiguration.getLogLevel().equals(LogLevel.DEBUG)

                         || UsageIssuesManagerImpl.getInstance().hasIssues()

                         || DIFStartupConfiguration.getDeveloperMode() || DIFStartupConfiguration.getTestingMode())

                 {

                     dumpDEM();

                 }

             }

             catch (ResourceNotFoundException resourceNotFoundException)

             {

                 resourceNotFoundException.printStackTrace();

             }

             catch (CodeGenerationException codeGenerationException)

             {

                 codeGenerationException.printStackTrace();

             }

             catch (DIFCodeGenerationException e)

             {

                 e.printStackTrace();

             }

             catch (InternalFrameworkException e)

             {

                 throw new RuntimeException(e);

             }

         }

         return initialized;

     }

     /**

      * Initialize APIs.

      * 

      * @throws InternalFrameworkException

      */

     private static void initializeAPIs() throws InternalFrameworkException

     {

         List<IDIFAPI> list = DIFIoCRegistry.getRegistry().getImplementations(IDIFAPI.class);

         Collections.sort(list, new Comparator<IDIFAPI>() {

             public int compare(IDIFAPI a, IDIFAPI b)

             {

                 return a.order().compareTo(b.order());

             }

         });

         for (IDIFAPI difApi: list)

         {

             difApi.initialize();

         }

     }

     /**

      * Initialize all registered DIF Applications.

      */

     synchronized static public void initializeApplications()

     {

         List<IApplicationConfiguration> appConfImpls = DIFIoCRegistry.getRegistry().getImplementations(

                 IApplicationConfiguration.class);

         if (appConfImpls.size() > 0)

         {

             appConfImpls.get(0).processConfigurations();

             DIFLogger.getLogger()

                     .info("Initializing Applications Configurations using: "

                             + appConfImpls.get(0).getClass().getSimpleName());

         }

         IDEMManager demManager = DIFIoCRegistry.getRegistry().getImplementation(IDEMManager.class);

         DIFLogger.getLogger().info("Initializing Applications...");

         for (IProvider provider: demManager.getProviders().values())

             for (IApplication application: provider.getApplications().values())

                 ((IApplicationPrivate) application).__CG__initialize();

     }

     /**

      * Initialization state inspector.

      * 

      * @return T if the framework has been initialized

      */

     synchronized static public boolean isInitialized()

     {

         return initialized;

     }

 }