/**
 * Orthanc - A Lightweight, RESTful DICOM Store
 * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
 * Department, University Hospital of Liege, Belgium
 * Copyright (C) 2017-2020 Osimis S.A., Belgium
 *
 * This program is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * In addition, as a special exception, the copyright holders of this
 * program give permission to link the code of its release with the
 * OpenSSL project's "OpenSSL" library (or with modified versions of it
 * that use the same license as the "OpenSSL" library), and distribute
 * the linked executables. You must obey the GNU General Public License
 * in all respects for all of the code used other than "OpenSSL". If you
 * modify file(s) with this exception, you may extend this exception to
 * your version of the file(s), but you are not obligated to do so. If
 * you do not wish to do so, delete this exception statement from your
 * version. If you delete this exception statement from all source files
 * in the program, then also delete it here.
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 **/


#include "PrecompiledHeadersServer.h"
#include "OrthancRestApi/OrthancRestApi.h"

#include <boost/algorithm/string/predicate.hpp>

#include "../../OrthancFramework/Sources/Compatibility.h"
#include "../../OrthancFramework/Sources/DicomFormat/DicomArray.h"
#include "../../OrthancFramework/Sources/DicomNetworking/DicomAssociationParameters.h"
#include "../../OrthancFramework/Sources/DicomNetworking/DicomServer.h"
#include "../../OrthancFramework/Sources/DicomParsing/FromDcmtkBridge.h"
#include "../../OrthancFramework/Sources/HttpServer/FilesystemHttpHandler.h"
#include "../../OrthancFramework/Sources/HttpServer/HttpServer.h"
#include "../../OrthancFramework/Sources/Logging.h"
#include "../../OrthancFramework/Sources/Lua/LuaFunctionCall.h"
#include "../Plugins/Engine/OrthancPlugins.h"
#include "EmbeddedResourceHttpHandler.h"
#include "OrthancConfiguration.h"
#include "OrthancFindRequestHandler.h"
#include "OrthancGetRequestHandler.h"
#include "OrthancInitialization.h"
#include "OrthancMoveRequestHandler.h"
#include "ServerContext.h"
#include "ServerJobs/StorageCommitmentScpJob.h"
#include "ServerToolbox.h"
#include "StorageCommitmentReports.h"

#include "../../OrthancFramework/Sources/HttpServer/WebDavStorage.h"  // TODO
#include "Search/DatabaseLookup.h"  // TODO
#include <boost/regex.hpp> // TODO


using namespace Orthanc;


class OrthancStoreRequestHandler : public IStoreRequestHandler
{
private:
  ServerContext& context_;

public:
  explicit OrthancStoreRequestHandler(ServerContext& context) :
    context_(context)
  {
  }


  virtual void Handle(const std::string& dicomFile,
                      const DicomMap& dicomSummary,
                      const Json::Value& dicomJson,
                      const std::string& remoteIp,
                      const std::string& remoteAet,
                      const std::string& calledAet) ORTHANC_OVERRIDE 
  {
    if (dicomFile.size() > 0)
    {
      DicomInstanceToStore toStore;
      toStore.SetOrigin(DicomInstanceOrigin::FromDicomProtocol
                        (remoteIp.c_str(), remoteAet.c_str(), calledAet.c_str()));
      toStore.SetBuffer(dicomFile.c_str(), dicomFile.size());
      toStore.SetSummary(dicomSummary);
      toStore.SetJson(dicomJson);

      std::string id;
      context_.Store(id, toStore, StoreInstanceMode_Default);
    }
  }
};



class OrthancStorageCommitmentRequestHandler : public IStorageCommitmentRequestHandler
{
private:
  ServerContext& context_;
  
public:
  explicit OrthancStorageCommitmentRequestHandler(ServerContext& context) :
    context_(context)
  {
  }

  virtual void HandleRequest(const std::string& transactionUid,
                             const std::vector<std::string>& referencedSopClassUids,
                             const std::vector<std::string>& referencedSopInstanceUids,
                             const std::string& remoteIp,
                             const std::string& remoteAet,
                             const std::string& calledAet) ORTHANC_OVERRIDE
  {
    if (referencedSopClassUids.size() != referencedSopInstanceUids.size())
    {
      throw OrthancException(ErrorCode_InternalError);
    }
    
    std::unique_ptr<StorageCommitmentScpJob> job(
      new StorageCommitmentScpJob(context_, transactionUid, remoteAet, calledAet));

    for (size_t i = 0; i < referencedSopClassUids.size(); i++)
    {
      job->AddInstance(referencedSopClassUids[i], referencedSopInstanceUids[i]);
    }

    job->MarkAsReady();

    context_.GetJobsEngine().GetRegistry().Submit(job.release(), 0 /* default priority */);
  }

  virtual void HandleReport(const std::string& transactionUid,
                            const std::vector<std::string>& successSopClassUids,
                            const std::vector<std::string>& successSopInstanceUids,
                            const std::vector<std::string>& failedSopClassUids,
                            const std::vector<std::string>& failedSopInstanceUids,
                            const std::vector<StorageCommitmentFailureReason>& failureReasons,
                            const std::string& remoteIp,
                            const std::string& remoteAet,
                            const std::string& calledAet) ORTHANC_OVERRIDE
  {
    if (successSopClassUids.size() != successSopInstanceUids.size() ||
        failedSopClassUids.size() != failedSopInstanceUids.size() ||
        failedSopClassUids.size() != failureReasons.size())
    {
      throw OrthancException(ErrorCode_InternalError);
    }
    
    std::unique_ptr<StorageCommitmentReports::Report> report(
      new StorageCommitmentReports::Report(remoteAet));

    for (size_t i = 0; i < successSopClassUids.size(); i++)
    {
      report->AddSuccess(successSopClassUids[i], successSopInstanceUids[i]);
    }

    for (size_t i = 0; i < failedSopClassUids.size(); i++)
    {
      report->AddFailure(failedSopClassUids[i], failedSopInstanceUids[i], failureReasons[i]);
    }

    report->MarkAsComplete();

    context_.GetStorageCommitmentReports().Store(transactionUid, report.release());
  }
};



class ModalitiesFromConfiguration : public DicomServer::IRemoteModalities
{
public:
  virtual bool IsSameAETitle(const std::string& aet1,
                             const std::string& aet2) ORTHANC_OVERRIDE
  {
    OrthancConfiguration::ReaderLock lock;
    return lock.GetConfiguration().IsSameAETitle(aet1, aet2);
  }

  virtual bool LookupAETitle(RemoteModalityParameters& modality,
                             const std::string& aet) ORTHANC_OVERRIDE
  {
    OrthancConfiguration::ReaderLock lock;
    return lock.GetConfiguration().LookupDicomModalityUsingAETitle(modality, aet);
  }
};


class MyDicomServerFactory : 
  public IStoreRequestHandlerFactory,
  public IFindRequestHandlerFactory, 
  public IMoveRequestHandlerFactory,
  public IGetRequestHandlerFactory,
  public IStorageCommitmentRequestHandlerFactory
{
private:
  ServerContext& context_;

public:
  explicit MyDicomServerFactory(ServerContext& context) : context_(context)
  {
  }

  virtual IStoreRequestHandler* ConstructStoreRequestHandler() ORTHANC_OVERRIDE
  {
    return new OrthancStoreRequestHandler(context_);
  }

  virtual IFindRequestHandler* ConstructFindRequestHandler() ORTHANC_OVERRIDE
  {
    std::unique_ptr<OrthancFindRequestHandler> result(new OrthancFindRequestHandler(context_));

    {
      OrthancConfiguration::ReaderLock lock;
      result->SetMaxResults(lock.GetConfiguration().GetUnsignedIntegerParameter("LimitFindResults", 0));
      result->SetMaxInstances(lock.GetConfiguration().GetUnsignedIntegerParameter("LimitFindInstances", 0));
    }

    if (result->GetMaxResults() == 0)
    {
      LOG(INFO) << "No limit on the number of C-FIND results at the Patient, Study and Series levels";
    }
    else
    {
      LOG(INFO) << "Maximum " << result->GetMaxResults() 
                << " results for C-FIND queries at the Patient, Study and Series levels";
    }

    if (result->GetMaxInstances() == 0)
    {
      LOG(INFO) << "No limit on the number of C-FIND results at the Instance level";
    }
    else
    {
      LOG(INFO) << "Maximum " << result->GetMaxInstances() 
                << " instances will be returned for C-FIND queries at the Instance level";
    }

    return result.release();
  }

  virtual IMoveRequestHandler* ConstructMoveRequestHandler() ORTHANC_OVERRIDE
  {
    return new OrthancMoveRequestHandler(context_);
  }
  
  virtual IGetRequestHandler* ConstructGetRequestHandler() ORTHANC_OVERRIDE
  {
    return new OrthancGetRequestHandler(context_);
  }
  
  virtual IStorageCommitmentRequestHandler* ConstructStorageCommitmentRequestHandler() ORTHANC_OVERRIDE
  {
    return new OrthancStorageCommitmentRequestHandler(context_);
  }
  

  void Done()
  {
  }
};


class OrthancApplicationEntityFilter : public IApplicationEntityFilter
{
private:
  ServerContext&  context_;
  bool            alwaysAllowEcho_;
  bool            alwaysAllowStore_;

public:
  explicit OrthancApplicationEntityFilter(ServerContext& context) :
    context_(context)
  {
    OrthancConfiguration::ReaderLock lock;
    alwaysAllowEcho_ = lock.GetConfiguration().GetBooleanParameter("DicomAlwaysAllowEcho", true);
    alwaysAllowStore_ = lock.GetConfiguration().GetBooleanParameter("DicomAlwaysAllowStore", true);
  }

  virtual bool IsAllowedConnection(const std::string& remoteIp,
                                   const std::string& remoteAet,
                                   const std::string& calledAet) ORTHANC_OVERRIDE
  {
    LOG(INFO) << "Incoming connection from AET " << remoteAet
              << " on IP " << remoteIp << ", calling AET " << calledAet;

    if (alwaysAllowEcho_ ||
        alwaysAllowStore_)
    {
      return true;
    }
    else
    {
      OrthancConfiguration::ReaderLock lock;
      return lock.GetConfiguration().IsKnownAETitle(remoteAet, remoteIp);
    }
  }

  virtual bool IsAllowedRequest(const std::string& remoteIp,
                                const std::string& remoteAet,
                                const std::string& calledAet,
                                DicomRequestType type) ORTHANC_OVERRIDE
  {
    LOG(INFO) << "Incoming " << EnumerationToString(type) << " request from AET "
              << remoteAet << " on IP " << remoteIp << ", calling AET " << calledAet;
    
    if (type == DicomRequestType_Echo &&
        alwaysAllowEcho_)
    {
      // Incoming C-Echo requests are always accepted, even from unknown AET
      return true;
    }
    else if (type == DicomRequestType_Store &&
             alwaysAllowStore_)
    {
      // Incoming C-Store requests are always accepted, even from unknown AET
      return true;
    }
    else
    {
      OrthancConfiguration::ReaderLock lock;

      std::list<RemoteModalityParameters> modalities;
      if (lock.GetConfiguration().LookupDicomModalitiesUsingAETitle(modalities, remoteAet))
      {
        if (modalities.size() == 1) // don't check the IP if there's only one modality with this AET
        {
          return modalities.front().IsRequestAllowed(type);
        }
        else // if there are multiple modalities with the same AET, check the one matching this IP
        {
          for (std::list<RemoteModalityParameters>::const_iterator it = modalities.begin(); it != modalities.end(); ++it)
          {
            if (it->GetHost() == remoteIp)
            {
              return it->IsRequestAllowed(type);
            }
          }

          LOG(WARNING) << "Unable to check DICOM authorization for AET " << remoteAet
                       << " on IP " << remoteIp << ", " << modalities.size()
                       << " modalites found with this AET but none of them matching the IP";
        }
        return false;
      }
      else
      {
        return false;
      }
    }
  }

  virtual bool IsAllowedTransferSyntax(const std::string& remoteIp,
                                       const std::string& remoteAet,
                                       const std::string& calledAet,
                                       TransferSyntax syntax) ORTHANC_OVERRIDE
  {
    std::string configuration;

    switch (syntax)
    {
      case TransferSyntax_Deflated:
        configuration = "DeflatedTransferSyntaxAccepted";
        break;

      case TransferSyntax_Jpeg:
        configuration = "JpegTransferSyntaxAccepted";
        break;

      case TransferSyntax_Jpeg2000:
        configuration = "Jpeg2000TransferSyntaxAccepted";
        break;

      case TransferSyntax_JpegLossless:
        configuration = "JpegLosslessTransferSyntaxAccepted";
        break;

      case TransferSyntax_Jpip:
        configuration = "JpipTransferSyntaxAccepted";
        break;

      case TransferSyntax_Mpeg2:
        configuration = "Mpeg2TransferSyntaxAccepted";
        break;

      case TransferSyntax_Mpeg4:
        configuration = "Mpeg4TransferSyntaxAccepted";
        break;

      case TransferSyntax_Rle:
        configuration = "RleTransferSyntaxAccepted";
        break;

      default: 
        throw OrthancException(ErrorCode_ParameterOutOfRange);
    }

    {
      std::string name = "Is" + configuration;

      LuaScripting::Lock lock(context_.GetLuaScripting());
      
      if (lock.GetLua().IsExistingFunction(name.c_str()))
      {
        LuaFunctionCall call(lock.GetLua(), name.c_str());
        call.PushString(remoteAet);
        call.PushString(remoteIp);
        call.PushString(calledAet);
        return call.ExecutePredicate();
      }
    }

    {
      OrthancConfiguration::ReaderLock lock;
      return lock.GetConfiguration().GetBooleanParameter(configuration, true);
    }
  }


  virtual bool IsUnknownSopClassAccepted(const std::string& remoteIp,
                                         const std::string& remoteAet,
                                         const std::string& calledAet) ORTHANC_OVERRIDE
  {
    static const char* configuration = "UnknownSopClassAccepted";

    {
      std::string lua = "Is" + std::string(configuration);

      LuaScripting::Lock lock(context_.GetLuaScripting());
      
      if (lock.GetLua().IsExistingFunction(lua.c_str()))
      {
        LuaFunctionCall call(lock.GetLua(), lua.c_str());
        call.PushString(remoteAet);
        call.PushString(remoteIp);
        call.PushString(calledAet);
        return call.ExecutePredicate();
      }
    }

    {
      OrthancConfiguration::ReaderLock lock;
      return lock.GetConfiguration().GetBooleanParameter(configuration, false);
    }
  }
};


class MyIncomingHttpRequestFilter : public IIncomingHttpRequestFilter
{
private:
  ServerContext&   context_;
  OrthancPlugins*  plugins_;

public:
  MyIncomingHttpRequestFilter(ServerContext& context,
                              OrthancPlugins* plugins) : 
    context_(context),
    plugins_(plugins)
  {
  }

  virtual bool IsAllowed(HttpMethod method,
                         const char* uri,
                         const char* ip,
                         const char* username,
                         const IHttpHandler::Arguments& httpHeaders,
                         const IHttpHandler::GetArguments& getArguments) ORTHANC_OVERRIDE
  {
#if ORTHANC_ENABLE_PLUGINS == 1
    if (plugins_ != NULL &&
        !plugins_->IsAllowed(method, uri, ip, username, httpHeaders, getArguments))
    {
      return false;
    }
#endif

    static const char* HTTP_FILTER = "IncomingHttpRequestFilter";

    LuaScripting::Lock lock(context_.GetLuaScripting());

    // Test if the instance must be filtered out
    if (lock.GetLua().IsExistingFunction(HTTP_FILTER))
    {
      LuaFunctionCall call(lock.GetLua(), HTTP_FILTER);

      switch (method)
      {
        case HttpMethod_Get:
          call.PushString("GET");
          break;

        case HttpMethod_Put:
          call.PushString("PUT");
          break;

        case HttpMethod_Post:
          call.PushString("POST");
          break;

        case HttpMethod_Delete:
          call.PushString("DELETE");
          break;

        default:
          return true;
      }

      call.PushString(uri);
      call.PushString(ip);
      call.PushString(username);
      call.PushStringMap(httpHeaders);

      if (!call.ExecutePredicate())
      {
        LOG(INFO) << "An incoming HTTP request has been discarded by the filter";
        return false;
      }
    }

    return true;
  }
};



class MyHttpExceptionFormatter : public IHttpExceptionFormatter
{
private:
  bool             describeErrors_;
  OrthancPlugins*  plugins_;

public:
  MyHttpExceptionFormatter(bool describeErrors,
                           OrthancPlugins* plugins) :
    describeErrors_(describeErrors),
    plugins_(plugins)
  {
  }

  virtual void Format(HttpOutput& output,
                      const OrthancException& exception,
                      HttpMethod method,
                      const char* uri) ORTHANC_OVERRIDE
  {
    {
      bool isPlugin = false;

#if ORTHANC_ENABLE_PLUGINS == 1
      if (plugins_ != NULL)
      {
        plugins_->GetErrorDictionary().LogError(exception.GetErrorCode(), true);
        isPlugin = true;
      }
#endif

      if (!isPlugin)
      {
        LOG(ERROR) << "Exception in the HTTP handler: " << exception.What();
      }
    }      

    Json::Value message = Json::objectValue;
    ErrorCode errorCode = exception.GetErrorCode();
    HttpStatus httpStatus = exception.GetHttpStatus();

    {
      bool isPlugin = false;

#if ORTHANC_ENABLE_PLUGINS == 1
      if (plugins_ != NULL &&
          plugins_->GetErrorDictionary().Format(message, httpStatus, exception))
      {
        errorCode = ErrorCode_Plugin;
        isPlugin = true;
      }
#endif

      if (!isPlugin)
      {
        message["Message"] = exception.What();
      }
    }

    if (!describeErrors_)
    {
      output.SendStatus(httpStatus);
    }
    else
    {
      message["Method"] = EnumerationToString(method);
      message["Uri"] = uri;
      message["HttpError"] = EnumerationToString(httpStatus);
      message["HttpStatus"] = httpStatus;
      message["OrthancError"] = EnumerationToString(errorCode);
      message["OrthancStatus"] = errorCode;

      if (exception.HasDetails())
      {
        message["Details"] = exception.GetDetails();
      }

      std::string info = message.toStyledString();
      output.SendStatus(httpStatus, info);
    }
  }
};







static const char* const UPLOAD_FOLDER = "upload";

class DummyBucket : public IWebDavBucket  // TODO
{
private:
  ServerContext&  context_;
  WebDavStorage   storage_;

  bool IsUploadedFolder(const UriComponents& path) const
  {
    return (path.size() >= 1 && path[0] == UPLOAD_FOLDER);
  }

public:
  DummyBucket(ServerContext& context,
              bool isMemory) :
    context_(context),
    storage_(isMemory)
  {
  }
  
  virtual bool IsExistingFolder(const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (IsUploadedFolder(path))
    {
      return storage_.IsExistingFolder(UriComponents(path.begin() + 1, path.end()));
    }
    else
    {
      return (path.size() == 0 ||
              (path.size() == 1 && path[0] == "Folder1") ||
              (path.size() == 2 && path[0] == "Folder1" && path[1] == "Folder2"));
    }
  }

  virtual bool ListCollection(Collection& collection,
                              const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (IsUploadedFolder(path))
    {
      return storage_.ListCollection(collection, UriComponents(path.begin() + 1, path.end()));
    }
    else if (IsExistingFolder(path))
    {
      if (path.empty())
      {
        collection.AddResource(new Folder(UPLOAD_FOLDER));
      }
      
      for (unsigned int i = 0; i < 5; i++)
      {
        std::unique_ptr<File> f(new File("IM" + boost::lexical_cast<std::string>(i) + ".dcm"));
        f->SetContentLength(1024 * i);
        f->SetMimeType(MimeType_PlainText);
        collection.AddResource(f.release());
      }
        
      for (unsigned int i = 0; i < 5; i++)
      {
        collection.AddResource(new Folder("Folder" + boost::lexical_cast<std::string>(i)));
      }

      return true;
    }
    else
    {
      return false;
    }
  }

  virtual bool GetFileContent(MimeType& mime,
                              std::string& content,
                              boost::posix_time::ptime& time, 
                              const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (path.empty())
    {
      return false;
    }
    else if (IsUploadedFolder(path))
    {
      return storage_.GetFileContent(mime, content, time,
                                     UriComponents(path.begin() + 1, path.end()));
    }
    else if (path.back() == "IM0.dcm" ||
             path.back() == "IM1.dcm" ||
             path.back() == "IM2.dcm" ||
             path.back() == "IM3.dcm" ||
             path.back() == "IM4.dcm")
    {
      time = boost::posix_time::second_clock::universal_time();

      std::string s;
      for (size_t i = 0; i < path.size(); i++)
      {
        s += "/" + path[i];
      }
      
      content = "Hello world!\r\n" + s + "\r\n";
      mime = MimeType_PlainText;
      return true;
    }
    else
    {
      return false;
    }
  }

  
  virtual bool StoreFile(const std::string& content,
                         const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (IsUploadedFolder(path))
    {
      return storage_.StoreFile(content, UriComponents(path.begin() + 1, path.end()));
    }
    else
    {
      LOG(WARNING) << "Writing to a read-only location in WebDAV: " << Toolbox::FlattenUri(path);
      return false;
    }
  }


  virtual bool CreateFolder(const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (IsUploadedFolder(path))
    {
      return storage_.CreateFolder(UriComponents(path.begin() + 1, path.end()));
    }
    else
    {
      LOG(WARNING) << "Writing to a read-only location in WebDAV: " << Toolbox::FlattenUri(path);
      return false;
    }
  }

  virtual bool DeleteItem(const std::vector<std::string>& path) ORTHANC_OVERRIDE
  {
    return false;  // read-only
  }

  virtual void Start() ORTHANC_OVERRIDE
  {
    LOG(WARNING) << "Starting WebDAV";
  }

  virtual void Stop() ORTHANC_OVERRIDE
  {
    LOG(WARNING) << "Stopping WebDAV";
  }
};





static const char* const BY_PATIENTS = "by-patients";
static const char* const BY_STUDIES = "by-studies";
static const char* const BY_DATE = "by-date";
static const char* const BY_UIDS = "by-uids";
static const char* const MAIN_DICOM_TAGS = "MainDicomTags";

class DummyBucket2 : public IWebDavBucket  // TODO
{
private:
  typedef std::map<ResourceType, std::string>  Templates;


  static void LookupTime(boost::posix_time::ptime& target,
                         ServerContext& context,
                         const std::string& publicId,
                         MetadataType metadata)
  {
    std::string value;
    if (context.GetIndex().LookupMetadata(value, publicId, metadata))
    {
      try
      {
        target = boost::posix_time::from_iso_string(value);
        return;
      }
      catch (std::exception& e)
      {
      }
    }

    target = boost::posix_time::second_clock::universal_time();  // Now
  }

  
  class DicomIdentifiersVisitor : public ServerContext::ILookupVisitor
  {
  private:
    ServerContext&  context_;
    bool            isComplete_;
    Collection&     target_;
    ResourceType    level_;

  public:
    DicomIdentifiersVisitor(ServerContext& context,
                            Collection&  target,
                            ResourceType level) :
      context_(context),
      isComplete_(false),
      target_(target),
      level_(level)
    {
    }
      
    virtual bool IsDicomAsJsonNeeded() const ORTHANC_OVERRIDE
    {
      return false;   // (*)
    }
      
    virtual void MarkAsComplete() ORTHANC_OVERRIDE
    {
      isComplete_ = true;  // TODO
    }

    virtual void Visit(const std::string& publicId,
                       const std::string& instanceId   /* unused     */,
                       const DicomMap& mainDicomTags,
                       const Json::Value* dicomAsJson  /* unused (*) */)  ORTHANC_OVERRIDE
    {
      DicomTag tag(0, 0);
      MetadataType timeMetadata;

      switch (level_)
      {
        case ResourceType_Study:
          tag = DICOM_TAG_STUDY_INSTANCE_UID;
          timeMetadata = MetadataType_LastUpdate;
          break;

        case ResourceType_Series:
          tag = DICOM_TAG_SERIES_INSTANCE_UID;
          timeMetadata = MetadataType_LastUpdate;
          break;
        
        case ResourceType_Instance:
          tag = DICOM_TAG_SOP_INSTANCE_UID;
          timeMetadata = MetadataType_Instance_ReceptionDate;
          break;

        default:
          throw OrthancException(ErrorCode_InternalError);
      }
        
      std::string s;
      if (mainDicomTags.LookupStringValue(s, tag, false) &&
          !s.empty())
      {
        std::unique_ptr<Resource> resource;

        if (level_ == ResourceType_Instance)
        {
          FileInfo info;
          if (context_.GetIndex().LookupAttachment(info, publicId, FileContentType_Dicom))
          {
            std::unique_ptr<File> f(new File(s + ".dcm"));
            f->SetMimeType(MimeType_Dicom);
            f->SetContentLength(info.GetUncompressedSize());
            resource.reset(f.release());
          }
        }
        else
        {
          resource.reset(new Folder(s));
        }

        if (resource.get() != NULL)
        {
          boost::posix_time::ptime t;
          LookupTime(t, context_, publicId, timeMetadata);
          resource->SetCreationTime(t);
          target_.AddResource(resource.release());
        }
      }
    }
  };
  
  class DicomFileVisitor : public ServerContext::ILookupVisitor
  {
  private:
    ServerContext&  context_;
    bool            success_;
    std::string&    target_;
    boost::posix_time::ptime&  time_;

  public:
    DicomFileVisitor(ServerContext& context,
                     std::string& target,
                     boost::posix_time::ptime& time) :
      context_(context),
      success_(false),
      target_(target),
      time_(time)
    {
    }

    bool IsSuccess() const
    {
      return success_;
    }

    virtual bool IsDicomAsJsonNeeded() const ORTHANC_OVERRIDE
    {
      return false;   // (*)
    }
      
    virtual void MarkAsComplete() ORTHANC_OVERRIDE
    {
    }

    virtual void Visit(const std::string& publicId,
                       const std::string& instanceId   /* unused     */,
                       const DicomMap& mainDicomTags,
                       const Json::Value* dicomAsJson  /* unused (*) */)  ORTHANC_OVERRIDE
    {
      if (success_)
      {
        success_ = false;  // Two matches => Error
      }
      else
      {
        LookupTime(time_, context_, publicId, MetadataType_Instance_ReceptionDate);
        context_.ReadDicom(target_, publicId);
        success_ = true;
      }
    }
  };
  
  class OrthancJsonVisitor : public ServerContext::ILookupVisitor
  {
  private:
    ServerContext&  context_;
    bool            success_;
    std::string&    target_;
    ResourceType    level_;

  public:
    OrthancJsonVisitor(ServerContext& context,
                       std::string& target,
                       ResourceType level) :
      context_(context),
      success_(false),
      target_(target),
      level_(level)
    {
    }

    bool IsSuccess() const
    {
      return success_;
    }

    virtual bool IsDicomAsJsonNeeded() const ORTHANC_OVERRIDE
    {
      return false;   // (*)
    }
      
    virtual void MarkAsComplete() ORTHANC_OVERRIDE
    {
    }

    virtual void Visit(const std::string& publicId,
                       const std::string& instanceId   /* unused     */,
                       const DicomMap& mainDicomTags,
                       const Json::Value* dicomAsJson  /* unused (*) */)  ORTHANC_OVERRIDE
    {
      Json::Value info;
      if (context_.GetIndex().LookupResource(info, publicId, level_))
      {
        if (success_)
        {
          success_ = false;  // Two matches => Error
        }
        else
        {
          target_ = info.toStyledString();

          // Replace UNIX newlines with DOS newlines 
          boost::replace_all(target_, "\n", "\r\n");

          success_ = true;
        }
      }
    }
  };


  void AddVirtualFile(Collection& collection,
                      const UriComponents& path,
                      const std::string& filename)
  {
    MimeType mime;
    std::string content;
    boost::posix_time::ptime modification;

    UriComponents p = path;
    p.push_back(filename);

    if (GetFileContent(mime, content, modification, p))
    {
      std::unique_ptr<File> f(new File(filename));
      f->SetMimeType(mime);
      f->SetContentLength(content.size());
      f->SetCreationTime(modification);
      collection.AddResource(f.release());
    }
  }




  class ResourcesIndex : public boost::noncopyable
  {
  public:
    typedef std::map<std::string, std::string>   Map;

  private:
    ServerContext&  context_;
    ResourceType    level_;
    std::string     template_;
    Map             pathToResource_;
    Map             resourceToPath_;

    void CheckInvariants()
    {
#ifndef NDEBUG
      assert(pathToResource_.size() == resourceToPath_.size());

      for (Map::const_iterator it = pathToResource_.begin(); it != pathToResource_.end(); ++it)
      {
        assert(resourceToPath_[it->second] == it->first);
      }

      for (Map::const_iterator it = resourceToPath_.begin(); it != resourceToPath_.end(); ++it)
      {
        assert(pathToResource_[it->second] == it->first);
      }
#endif
    }      

    void AddTags(DicomMap& target,
                 const std::string& resourceId,
                 ResourceType tagsFromLevel)
    {
      DicomMap tags;
      if (context_.GetIndex().GetMainDicomTags(tags, resourceId, level_, tagsFromLevel))
      {
        target.Merge(tags);
      }
    }

    void Register(const std::string& resourceId)
    {
      // Don't register twice the same resource
      if (resourceToPath_.find(resourceId) == resourceToPath_.end())
      {
        std::string name = template_;

        DicomMap tags;

        AddTags(tags, resourceId, level_);
        
        if (level_ == ResourceType_Study)
        {
          AddTags(tags, resourceId, ResourceType_Patient);
        }
        
        DicomArray arr(tags);
        for (size_t i = 0; i < arr.GetSize(); i++)
        {
          const DicomElement& element = arr.GetElement(i);
          if (!element.GetValue().IsNull() &&
              !element.GetValue().IsBinary())
          {
            const std::string tag = FromDcmtkBridge::GetTagName(element.GetTag(), "");
            boost::replace_all(name, "{{" + tag + "}}", element.GetValue().GetContent());
          } 
        }

        // Blank the tags that were not matched
        static const boost::regex REGEX_BLANK_TAGS("{{.*?}}");  // non-greedy match
        name = boost::regex_replace(name, REGEX_BLANK_TAGS, "");

        // UTF-8 characters cannot be used on Windows XP
        name = Toolbox::ConvertToAscii(name);
        boost::replace_all(name, "/", "");
        boost::replace_all(name, "\\", "");

        // Trim sequences of spaces as one single space
        static const boost::regex REGEX_TRIM_SPACES("{{.*?}}");
        name = boost::regex_replace(name, REGEX_TRIM_SPACES, " ");
        name = Toolbox::StripSpaces(name);

        size_t count = 0;
        for (;;)
        {
          std::string path = name;
          if (count > 0)
          {
            path += " (" + boost::lexical_cast<std::string>(count) + ")";
          }

          if (pathToResource_.find(path) == pathToResource_.end())
          {
            pathToResource_[path] = resourceId;
            resourceToPath_[resourceId] = path;
            return;
          }

          count++;
        }

        throw OrthancException(ErrorCode_InternalError);
      }
    }

  public:
    ResourcesIndex(ServerContext& context,
                   ResourceType level,
                   const std::string& templateString) :
      context_(context),
      level_(level),
      template_(templateString)
    {
    }

    ResourceType GetLevel() const
    {
      return level_;
    }

    void Refresh(std::set<std::string>& removedPaths /* out */,
                 const std::set<std::string>& resources)
    {
      CheckInvariants();

      // Detect the resources that have been removed since last refresh
      removedPaths.clear();
      std::set<std::string> removedResources;
      
      for (Map::iterator it = resourceToPath_.begin(); it != resourceToPath_.end(); ++it)
      {
        if (resources.find(it->first) == resources.end())
        {
          const std::string& path = it->second;
          
          assert(pathToResource_.find(path) != pathToResource_.end());
          pathToResource_.erase(path);
          removedPaths.insert(path);
          
          removedResources.insert(it->first);  // Delay the removal to avoid disturbing the iterator
        }
      }

      // Remove the missing resources
      for (std::set<std::string>::const_iterator it = removedResources.begin(); it != removedResources.end(); ++it)
      {
        assert(resourceToPath_.find(*it) != resourceToPath_.end());
        resourceToPath_.erase(*it);
      }

      CheckInvariants();

      for (std::set<std::string>::const_iterator it = resources.begin(); it != resources.end(); ++it)
      {
        Register(*it);
      }

      CheckInvariants();
    }

    const Map& GetPathToResource() const
    {
      return pathToResource_;
    }
  };


  class INode : public boost::noncopyable
  {
  public:
    virtual ~INode()
    {
    }

    virtual bool ListCollection(IWebDavBucket::Collection& target,
                                const UriComponents& path) = 0;

    virtual bool GetFileContent(MimeType& mime,
                                std::string& content,
                                boost::posix_time::ptime& time, 
                                const UriComponents& path) = 0;
  };


  
  class InstancesNode : public INode
  {
  private:
    ServerContext&  context_;
    std::string     parentSeries_;

  public:
    InstancesNode(ServerContext& context,
                  const std::string& parentSeries) :
      context_(context),
      parentSeries_(parentSeries)
    {
    }

    virtual bool ListCollection(IWebDavBucket::Collection& target,
                                const UriComponents& path) ORTHANC_OVERRIDE
    {
      if (path.empty())
      {
        std::list<std::string> resources;
        try
        {
          context_.GetIndex().GetChildren(resources, parentSeries_);
        }
        catch (OrthancException&)
        {
          // Unknown (or deleted) parent series
          return false;
        }

        for (std::list<std::string>::const_iterator
               it = resources.begin(); it != resources.end(); ++it)
        {
          boost::posix_time::ptime time;
          LookupTime(time, context_, *it, MetadataType_Instance_ReceptionDate);

          FileInfo info;
          if (context_.GetIndex().LookupAttachment(info, *it, FileContentType_Dicom))
          {
            std::unique_ptr<File> resource(new File(*it + ".dcm"));
            resource->SetMimeType(MimeType_Dicom);
            resource->SetContentLength(info.GetUncompressedSize());
            resource->SetCreationTime(time);
            target.AddResource(resource.release());
          }          
        }
        
        return true;
      }
      else
      {
        return false;
      }
    }

    virtual bool GetFileContent(MimeType& mime,
                                std::string& content,
                                boost::posix_time::ptime& time, 
                                const UriComponents& path) ORTHANC_OVERRIDE
    {
      if (path.size() == 1 &&
          boost::ends_with(path[0], ".dcm"))
      {
        std::string instanceId = path[0].substr(0, path[0].size() - 4);

        try
        {
          mime = MimeType_Dicom;
          context_.ReadDicom(content, instanceId);
          LookupTime(time, context_, instanceId, MetadataType_Instance_ReceptionDate);
          return true;
        }
        catch (OrthancException&)
        {
          // File was removed
          return false;
        }
      }
      else
      {
        return false;
      }
    }
  };



  /**
   * The "InternalNode" class corresponds to a non-leaf node in the
   * WebDAV tree, that only contains subfolders (no file).
   * 
   * TODO: Implement a LRU index to dynamically remove the oldest
   * children on high RAM usage.
   **/
  class InternalNode : public INode
  {
  private:
    typedef std::map<std::string, INode*>  Children;

    Children  children_;

    INode* GetChild(const std::string& path)  // Don't delete the result pointer!
    {
      Children::const_iterator child = children_.find(path);
      if (child == children_.end())
      {
        INode* child = CreateChild(path);
        
        if (child == NULL)
        {
          return NULL;
        }
        else
        {
          children_[path] = child;
          return child;
        }
      }
      else
      {
        assert(child->second != NULL);
        return child->second;
      }
    }

  protected:
    virtual void Refresh() = 0;
    
    virtual bool ListContent(IWebDavBucket::Collection& target) = 0;

    virtual INode* CreateChild(const std::string& path) = 0;

  public:
    virtual ~InternalNode()
    {
      for (Children::iterator it = children_.begin(); it != children_.end(); ++it)
      {
        assert(it->second != NULL);
        delete it->second;
      }
    }

    virtual bool ListCollection(IWebDavBucket::Collection& target,
                                const UriComponents& path)
      ORTHANC_OVERRIDE ORTHANC_FINAL
    {
      Refresh();
      
      if (path.empty())
      {
        return ListContent(target);
      }
      else
      {
        // Recursivity
        INode* child = GetChild(path[0]);
        if (child == NULL)
        {
          return false;
        }
        else
        {
          UriComponents subpath(path.begin() + 1, path.end());
          return child->ListCollection(target, subpath);
        }
      }
    }

    virtual bool GetFileContent(MimeType& mime,
                                std::string& content,
                                boost::posix_time::ptime& time, 
                                const UriComponents& path)
      ORTHANC_OVERRIDE ORTHANC_FINAL
    {
      if (path.empty())
      {
        return false;
      }
      else
      {
        // Recursivity
        Refresh();
      
        INode* child = GetChild(path[0]);
        if (child == NULL)
        {
          return false;
        }
        else
        {
          UriComponents subpath(path.begin() + 1, path.end());
          return child->GetFileContent(mime, content, time, subpath);
        }
      }
    }
  };
  

  class ResourcesNode : public INode
  {
  private:
    typedef std::map<std::string, INode*>  Children;
    
    ServerContext&                   context_;
    const Templates&                 templates_;
    std::unique_ptr<ResourcesIndex>  index_;
    MetadataType                     timeMetadata_;
    Children                         children_;  // Maps paths to subnodes

    void Refresh()
    {
      std::list<std::string> resources;
      GetCurrentResources(resources);

      std::set<std::string> removedPaths;
      index_->Refresh(removedPaths, std::set<std::string>(resources.begin(), resources.end()));

      // Remove the children whose associated resource doesn't exist anymore
      for (std::set<std::string>::const_iterator
             it = removedPaths.begin(); it != removedPaths.end(); ++it)
      {
        Children::iterator child = children_.find(*it);
        if (child != children_.end())
        {
          assert(child->second != NULL);
          delete child->second;
          children_.erase(child);
        }
      }
    }

    INode* GetChild(const std::string& path)  // Don't free the resulting pointer!
    {
      Children::iterator child = children_.find(path);
      if (child == children_.end())
      {
        INode* child = CreateChild(path);
        if (child == NULL)
        {            
          return NULL;
        }
        else
        {
          children_[path] = child;
          return child;
        }
      }
      else
      {
        assert(child->second != NULL);
        return child->second;
      }
    }

  protected:
    ServerContext& GetContext() const
    {
      return context_;
    }
    
    virtual void GetCurrentResources(std::list<std::string>& resources) = 0;

    virtual INode* CreateChild(const std::string& path)
    {
      ResourcesIndex::Map::const_iterator resource = index_->GetPathToResource().find(path);
      if (resource == index_->GetPathToResource().end())
      {
        return NULL;
      }
      else
      {
        return CreateResourceNode(resource->second);
      }
    }

    virtual INode* CreateResourceNode(const std::string& resource) = 0;
    
  public:
    ResourcesNode(ServerContext& context,
                  ResourceType level,
                  const Templates& templates) :
      context_(context),
      templates_(templates)
    {
      Templates::const_iterator t = templates.find(level);
      if (t == templates.end())
      {
        throw OrthancException(ErrorCode_ParameterOutOfRange);
      }
      
      index_.reset(new ResourcesIndex(context, level, t->second));
      
      if (level == ResourceType_Instance)
      {
        timeMetadata_ = MetadataType_Instance_ReceptionDate;
      }
      else
      {
        timeMetadata_ = MetadataType_LastUpdate;
      }
    }

    virtual ~ResourcesNode()
    {
      for (Children::iterator it = children_.begin(); it != children_.end(); ++it)
      {
        assert(it->second != NULL);
        delete it->second;
      }        
    }

    ResourceType GetLevel() const
    {
      return index_->GetLevel();
    }

    const Templates& GetTemplates() const
    {
      return templates_;
    }

    virtual bool ListCollection(IWebDavBucket::Collection& target,
                                const UriComponents& path)
      ORTHANC_OVERRIDE ORTHANC_FINAL
    {
      Refresh();

      if (index_->GetLevel() == ResourceType_Instance)
      {
        // Not a collection, no subfolders
        return false;
      }
      else if (path.empty())
      {
        const ResourcesIndex::Map& paths = index_->GetPathToResource();
        
        for (ResourcesIndex::Map::const_iterator it = paths.begin(); it != paths.end(); ++it)
        {
          boost::posix_time::ptime time;
          LookupTime(time, context_, it->second, timeMetadata_);

          std::unique_ptr<IWebDavBucket::Resource> resource(new IWebDavBucket::Folder(it->first));
          resource->SetCreationTime(time);
          target.AddResource(resource.release());
        }

        return true;
      }
      else
      {
        // Recursivity
        INode* child = GetChild(path[0]);
        if (child == NULL)
        {
          return false;
        }
        else
        {
          UriComponents subpath(path.begin() + 1, path.end());
          return child->ListCollection(target, subpath);
        }
      }
    }

    virtual bool GetFileContent(MimeType& mime,
                                std::string& content,
                                boost::posix_time::ptime& time, 
                                const UriComponents& path)
      ORTHANC_OVERRIDE ORTHANC_FINAL
    {
      if (path.empty())
      {
        return false;
      }
      else
      {
        // Recursivity
        Refresh();

        INode* child = GetChild(path[0]);
        if (child == NULL)
        {
          return false;
        }
        else
        {
          UriComponents subpath(path.begin() + 1, path.end());
          return child->GetFileContent(mime, content, time, subpath);
        }
      }
    }
  };

  

  class ResourceChildrenNode : public ResourcesNode
  {
  private:
    std::string  parentId_;
    
  protected: 
    virtual void GetCurrentResources(std::list<std::string>& resources) ORTHANC_OVERRIDE
    {
      try
      {
        GetContext().GetIndex().GetChildren(resources, parentId_);
      }
      catch (OrthancException&)
      {
        // Unknown parent resource
        resources.clear();
      }
    }

    virtual INode* CreateResourceNode(const std::string& resource) ORTHANC_OVERRIDE
    {
      if (GetLevel() == ResourceType_Instance)
      {
        return NULL;
      }
      else if (GetLevel() == ResourceType_Series)
      {
        return new InstancesNode(GetContext(), resource);
      }
      else
      {
        ResourceType l = GetChildResourceType(GetLevel());
        return new ResourceChildrenNode(GetContext(), l, resource, GetTemplates());
      }
    }

  public:
    ResourceChildrenNode(ServerContext& context,
                         ResourceType level,
                         const std::string& parentId,
                         const Templates& templates) :
      ResourcesNode(context, level, templates),
      parentId_(parentId)
    {
    }
  };
  
  
  class RootNode : public ResourcesNode
  {
  protected:   
    virtual void GetCurrentResources(std::list<std::string>& resources) ORTHANC_OVERRIDE
    {
      GetContext().GetIndex().GetAllUuids(resources, GetLevel());
    }

    virtual INode* CreateResourceNode(const std::string& resource) ORTHANC_OVERRIDE
    {
      if (GetLevel() == ResourceType_Series)
      {
        return new InstancesNode(GetContext(), resource);
      }
      else
      {
        ResourceType l = GetChildResourceType(GetLevel());
        return new ResourceChildrenNode(GetContext(), l, resource, GetTemplates());
      }
    }

  public:
    RootNode(ServerContext& context,
             ResourceType level,
             const Templates& templates) :
      ResourcesNode(context, level, templates)
    {
    }
  };



  class StudyMonthsNode : public InternalNode
  {
  private:
    ServerContext&    context_;
    std::string       year_;
    const Templates&  templates_;

    class Visitor : public ServerContext::ILookupVisitor
    {
    private:
      std::set<std::string> months_;
      
    public:
      Visitor()
      {
      }

      const std::set<std::string>& GetMonths() const
      {
        return months_;
      }
      
      virtual bool IsDicomAsJsonNeeded() const ORTHANC_OVERRIDE
      {
        return false;   // (*)
      }
      
      virtual void MarkAsComplete() ORTHANC_OVERRIDE
      {
      }

      virtual void Visit(const std::string& publicId,
                         const std::string& instanceId   /* unused     */,
                         const DicomMap& mainDicomTags,
                         const Json::Value* dicomAsJson  /* unused (*) */)  ORTHANC_OVERRIDE
      {
        std::string s;
        if (mainDicomTags.LookupStringValue(s, DICOM_TAG_STUDY_DATE, false) &&
            s.size() == 8)
        {
          months_.insert(s.substr(4, 2)); // Get the month from "YYYYMMDD"
        }
      }
    };

  protected:
    virtual void Refresh() ORTHANC_OVERRIDE
    {
    }

    virtual bool ListContent(IWebDavBucket::Collection& target) ORTHANC_OVERRIDE
    {
      DatabaseLookup query;
      query.AddRestConstraint(DICOM_TAG_STUDY_DATE, year_ + "0101-" + year_ + "1231",
                              true /* case sensitive */, true /* mandatory tag */);

      Visitor visitor;
      context_.Apply(visitor, query, ResourceType_Study, 0 /* since */, 0 /* no limit */);

      for (std::set<std::string>::const_iterator it = visitor.GetMonths().begin();
           it != visitor.GetMonths().end(); ++it)
      {
        target.AddResource(new IWebDavBucket::Folder(year_ + "-" + *it));
      }

      return true;
    }

    virtual INode* CreateChild(const std::string& path) ORTHANC_OVERRIDE
    {
      return NULL;
    }

  public:
    StudyMonthsNode(ServerContext& context,
                    const std::string& year,
                    const Templates& templates) :
      context_(context),
      year_(year),
      templates_(templates)
    {
    }
  };

  
  class StudyYearsNode : public InternalNode
  {
  private:
    ServerContext&    context_;
    const Templates&  templates_;

  protected:
    virtual void Refresh() ORTHANC_OVERRIDE
    {
    }

    virtual bool ListContent(IWebDavBucket::Collection& target) ORTHANC_OVERRIDE
    {
      std::list<std::string> resources;
      context_.GetIndex().GetAllUuids(resources, ResourceType_Study);

      std::set<std::string> years;
      
      for (std::list<std::string>::const_iterator it = resources.begin(); it != resources.end(); ++it)
      {
        DicomMap tags;
        std::string studyDate;
        if (context_.GetIndex().GetMainDicomTags(tags, *it, ResourceType_Study, ResourceType_Study) &&
            tags.LookupStringValue(studyDate, DICOM_TAG_STUDY_DATE, false) &&
            studyDate.size() == 8)
        {
          years.insert(studyDate.substr(0, 4)); // Get the year from "YYYYMMDD"
        }
      }
      
      for (std::set<std::string>::const_iterator it = years.begin(); it != years.end(); ++it)
      {
        target.AddResource(new IWebDavBucket::Folder(*it));
      }

      return true;
    }

    virtual INode* CreateChild(const std::string& path) ORTHANC_OVERRIDE
    {
      return new StudyMonthsNode(context_, path, templates_);
    }

  public:
    StudyYearsNode(ServerContext& context,
                   const Templates& templates) :
      context_(context),
      templates_(templates)
    {
    }
  };

  
  ServerContext&          context_;
  std::unique_ptr<INode>  patients_;
  std::unique_ptr<INode>  studies_;
  std::unique_ptr<INode>  dates_;
  Templates               patientsTemplates_;
  Templates               studiesTemplates_;
  

public:
  DummyBucket2(ServerContext& context) :
    context_(context)
  {
    patientsTemplates_[ResourceType_Patient] = "{{PatientID}} - {{PatientName}}";
    patientsTemplates_[ResourceType_Study] = "{{StudyDate}} - {{StudyDescription}}";
    patientsTemplates_[ResourceType_Series] = "{{Modality}} - {{SeriesDescription}}";

    studiesTemplates_[ResourceType_Study] = "{{PatientID}} - {{PatientName}} - {{StudyDescription}}";
    studiesTemplates_[ResourceType_Series] = patientsTemplates_[ResourceType_Series];

    patients_.reset(new RootNode(context, ResourceType_Patient, patientsTemplates_));
    studies_.reset(new RootNode(context, ResourceType_Study, studiesTemplates_));
    dates_.reset(new StudyYearsNode(context, studiesTemplates_));
  }

  virtual bool IsExistingFolder(const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (path.empty())
    {
      return true;
    }
    else if (path[0] == BY_UIDS)
    {
      return (path.size() <= 3 &&
              (path.size() != 3 || path[2] != "study.json"));
    }
    else if (path[0] == BY_PATIENTS)
    {
      IWebDavBucket::Collection tmp;
      return patients_->ListCollection(tmp, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_STUDIES)
    {
      IWebDavBucket::Collection tmp;
      return studies_->ListCollection(tmp, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_DATE)
    {
      IWebDavBucket::Collection tmp;
      return dates_->ListCollection(tmp, UriComponents(path.begin() + 1, path.end()));
    }
    else
    {
      return false;
    }
  }

  virtual bool ListCollection(Collection& collection,
                              const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (path.empty())
    {
      collection.AddResource(new Folder(BY_DATE));
      collection.AddResource(new Folder(BY_PATIENTS));
      collection.AddResource(new Folder(BY_STUDIES));
      collection.AddResource(new Folder(BY_UIDS));
      return true;
    }   
    else if (path[0] == BY_UIDS)
    {
      DatabaseLookup query;
      ResourceType level;
      size_t limit = 0;  // By default, no limits

      if (path.size() == 1)
      {
        level = ResourceType_Study;
        limit = 100;  // TODO
      }
      else if (path.size() == 2)
      {
        AddVirtualFile(collection, path, "study.json");

        level = ResourceType_Series;
        query.AddRestConstraint(DICOM_TAG_STUDY_INSTANCE_UID, path[1],
                                true /* case sensitive */, true /* mandatory tag */);
      }      
      else if (path.size() == 3)
      {
        AddVirtualFile(collection, path, "series.json");

        level = ResourceType_Instance;
        query.AddRestConstraint(DICOM_TAG_STUDY_INSTANCE_UID, path[1],
                                true /* case sensitive */, true /* mandatory tag */);
        query.AddRestConstraint(DICOM_TAG_SERIES_INSTANCE_UID, path[2],
                                true /* case sensitive */, true /* mandatory tag */);
      }
      else
      {
        return false;
      }

      DicomIdentifiersVisitor visitor(context_, collection, level);
      context_.Apply(visitor, query, level, 0 /* since */, limit);
      
      return true;
    }
    else if (path[0] == BY_PATIENTS)
    {
      return patients_->ListCollection(collection, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_STUDIES)
    {
      return studies_->ListCollection(collection, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_DATE)
    {
      return dates_->ListCollection(collection, UriComponents(path.begin() + 1, path.end()));
    }
    else
    {
      return false;
    }
  }

  virtual bool GetFileContent(MimeType& mime,
                              std::string& content,
                              boost::posix_time::ptime& modificationTime, 
                              const UriComponents& path) ORTHANC_OVERRIDE
  {
    if (path.empty())
    {
      return false;
    }
    else if (path[0] == BY_UIDS)
    {
      if (path.size() == 3 &&
          path[2] == "study.json")
      {
        DatabaseLookup query;
        query.AddRestConstraint(DICOM_TAG_STUDY_INSTANCE_UID, path[1],
                                true /* case sensitive */, true /* mandatory tag */);
      
        OrthancJsonVisitor visitor(context_, content, ResourceType_Study);
        context_.Apply(visitor, query, ResourceType_Study, 0 /* since */, 0 /* no limit */);

        mime = MimeType_Json;
        return visitor.IsSuccess();
      }
      else if (path.size() == 4 &&
               path[3] == "series.json")
      {
        DatabaseLookup query;
        query.AddRestConstraint(DICOM_TAG_STUDY_INSTANCE_UID, path[1],
                                true /* case sensitive */, true /* mandatory tag */);
        query.AddRestConstraint(DICOM_TAG_SERIES_INSTANCE_UID, path[2],
                                true /* case sensitive */, true /* mandatory tag */);
      
        OrthancJsonVisitor visitor(context_, content, ResourceType_Series);
        context_.Apply(visitor, query, ResourceType_Series, 0 /* since */, 0 /* no limit */);

        mime = MimeType_Json;
        return visitor.IsSuccess();
      }
      else if (path.size() == 4 &&
               boost::ends_with(path[3], ".dcm"))
      {
        std::string sopInstanceUid = path[3];
        sopInstanceUid.resize(sopInstanceUid.size() - 4);
        
        DatabaseLookup query;
        query.AddRestConstraint(DICOM_TAG_STUDY_INSTANCE_UID, path[1],
                                true /* case sensitive */, true /* mandatory tag */);
        query.AddRestConstraint(DICOM_TAG_SERIES_INSTANCE_UID, path[2],
                                true /* case sensitive */, true /* mandatory tag */);
        query.AddRestConstraint(DICOM_TAG_SOP_INSTANCE_UID, sopInstanceUid,
                                true /* case sensitive */, true /* mandatory tag */);
      
        DicomFileVisitor visitor(context_, content, modificationTime);
        context_.Apply(visitor, query, ResourceType_Instance, 0 /* since */, 0 /* no limit */);
        
        mime = MimeType_Dicom;
        return visitor.IsSuccess();
      }
    }
    else if (path[0] == BY_PATIENTS)
    {
      return patients_->GetFileContent(mime, content, modificationTime, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_STUDIES)
    {
      return studies_->GetFileContent(mime, content, modificationTime, UriComponents(path.begin() + 1, path.end()));
    }
    else if (path[0] == BY_DATE)
    {
      return dates_->GetFileContent(mime, content, modificationTime, UriComponents(path.begin() + 1, path.end()));
    }
      
    return false;
  }

  
  virtual bool StoreFile(const std::string& content,
                         const UriComponents& path) ORTHANC_OVERRIDE
  {
    return false;
  }


  virtual bool CreateFolder(const UriComponents& path)
  {
    return false;
  }

  virtual bool DeleteItem(const std::vector<std::string>& path) ORTHANC_OVERRIDE
  {
    LOG(WARNING) << "DELETE: " << Toolbox::FlattenUri(path);
    return false;  // read-only
  }

  virtual void Start() ORTHANC_OVERRIDE
  {
  }

  virtual void Stop() ORTHANC_OVERRIDE
  {
  }
};



static void PrintHelp(const char* path)
{
  std::cout 
    << "Usage: " << path << " [OPTION]... [CONFIGURATION]" << std::endl
    << "Orthanc, lightweight, RESTful DICOM server for healthcare and medical research." << std::endl
    << std::endl
    << "The \"CONFIGURATION\" argument can be a single file or a directory. In the " << std::endl
    << "case of a directory, all the JSON files it contains will be merged. " << std::endl
    << "If no configuration path is given on the command line, a set of default " << std::endl
    << "parameters is used. Please refer to the Orthanc homepage for the full " << std::endl
    << "instructions about how to use Orthanc <http://www.orthanc-server.com/>." << std::endl
    << std::endl
    << "Command-line options:" << std::endl
    << "  --help\t\tdisplay this help and exit" << std::endl
    << "  --logdir=[dir]\tdirectory where to store the log files" << std::endl
    << "\t\t\t(by default, the log is dumped to stderr)" << std::endl
    << "  --logfile=[file]\tfile where to store the log of Orthanc" << std::endl
    << "\t\t\t(by default, the log is dumped to stderr)" << std::endl
    << "  --config=[file]\tcreate a sample configuration file and exit" << std::endl
    << "\t\t\t(if file is \"-\", dumps to stdout)" << std::endl
    << "  --errors\t\tprint the supported error codes and exit" << std::endl
    << "  --verbose\t\tbe verbose in logs" << std::endl
    << "  --trace\t\thighest verbosity in logs (for debug)" << std::endl
    << "  --upgrade\t\tallow Orthanc to upgrade the version of the" << std::endl
    << "\t\t\tdatabase (beware that the database will become" << std::endl
    << "\t\t\tincompatible with former versions of Orthanc)" << std::endl
    << "  --no-jobs\t\tDon't restart the jobs that were stored during" << std::endl
    << "\t\t\tthe last execution of Orthanc" << std::endl
    << "  --version\t\toutput version information and exit" << std::endl
    << std::endl
    << "Exit status:" << std::endl
    << "   0 if success," << std::endl
#if defined(_WIN32)
    << "!= 0 if error (use the --errors option to get the list of possible errors)." << std::endl
#else
    << "  -1 if error (have a look at the logs)." << std::endl
#endif
    << std::endl;
}


static void PrintVersion(const char* path)
{
  std::cout
    << path << " " << ORTHANC_VERSION << std::endl
    << "Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics Department, University Hospital of Liege (Belgium)" << std::endl
    << "Copyright (C) 2017-2020 Osimis S.A. (Belgium)" << std::endl
    << "Licensing GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>, with OpenSSL exception." << std::endl
    << "This is free software: you are free to change and redistribute it." << std::endl
    << "There is NO WARRANTY, to the extent permitted by law." << std::endl
    << std::endl
    << "Written by Sebastien Jodogne <s.jodogne@orthanc-labs.com>" << std::endl;
}


static void PrintErrorCode(ErrorCode code, const char* description)
{
  std::cout 
    << std::right << std::setw(16) 
    << static_cast<int>(code)
    << "   " << description << std::endl;
}


static void PrintErrors(const char* path)
{
  std::cout
    << path << " " << ORTHANC_VERSION << std::endl
    << "Orthanc, lightweight, RESTful DICOM server for healthcare and medical research." 
    << std::endl << std::endl
    << "List of error codes that could be returned by Orthanc:" 
    << std::endl << std::endl;

  // The content of the following brackets is automatically generated
  // by the "GenerateErrorCodes.py" script
  {
    PrintErrorCode(ErrorCode_InternalError, "Internal error");
    PrintErrorCode(ErrorCode_Success, "Success");
    PrintErrorCode(ErrorCode_Plugin, "Error encountered within the plugin engine");
    PrintErrorCode(ErrorCode_NotImplemented, "Not implemented yet");
    PrintErrorCode(ErrorCode_ParameterOutOfRange, "Parameter out of range");
    PrintErrorCode(ErrorCode_NotEnoughMemory, "The server hosting Orthanc is running out of memory");
    PrintErrorCode(ErrorCode_BadParameterType, "Bad type for a parameter");
    PrintErrorCode(ErrorCode_BadSequenceOfCalls, "Bad sequence of calls");
    PrintErrorCode(ErrorCode_InexistentItem, "Accessing an inexistent item");
    PrintErrorCode(ErrorCode_BadRequest, "Bad request");
    PrintErrorCode(ErrorCode_NetworkProtocol, "Error in the network protocol");
    PrintErrorCode(ErrorCode_SystemCommand, "Error while calling a system command");
    PrintErrorCode(ErrorCode_Database, "Error with the database engine");
    PrintErrorCode(ErrorCode_UriSyntax, "Badly formatted URI");
    PrintErrorCode(ErrorCode_InexistentFile, "Inexistent file");
    PrintErrorCode(ErrorCode_CannotWriteFile, "Cannot write to file");
    PrintErrorCode(ErrorCode_BadFileFormat, "Bad file format");
    PrintErrorCode(ErrorCode_Timeout, "Timeout");
    PrintErrorCode(ErrorCode_UnknownResource, "Unknown resource");
    PrintErrorCode(ErrorCode_IncompatibleDatabaseVersion, "Incompatible version of the database");
    PrintErrorCode(ErrorCode_FullStorage, "The file storage is full");
    PrintErrorCode(ErrorCode_CorruptedFile, "Corrupted file (e.g. inconsistent MD5 hash)");
    PrintErrorCode(ErrorCode_InexistentTag, "Inexistent tag");
    PrintErrorCode(ErrorCode_ReadOnly, "Cannot modify a read-only data structure");
    PrintErrorCode(ErrorCode_IncompatibleImageFormat, "Incompatible format of the images");
    PrintErrorCode(ErrorCode_IncompatibleImageSize, "Incompatible size of the images");
    PrintErrorCode(ErrorCode_SharedLibrary, "Error while using a shared library (plugin)");
    PrintErrorCode(ErrorCode_UnknownPluginService, "Plugin invoking an unknown service");
    PrintErrorCode(ErrorCode_UnknownDicomTag, "Unknown DICOM tag");
    PrintErrorCode(ErrorCode_BadJson, "Cannot parse a JSON document");
    PrintErrorCode(ErrorCode_Unauthorized, "Bad credentials were provided to an HTTP request");
    PrintErrorCode(ErrorCode_BadFont, "Badly formatted font file");
    PrintErrorCode(ErrorCode_DatabasePlugin, "The plugin implementing a custom database back-end does not fulfill the proper interface");
    PrintErrorCode(ErrorCode_StorageAreaPlugin, "Error in the plugin implementing a custom storage area");
    PrintErrorCode(ErrorCode_EmptyRequest, "The request is empty");
    PrintErrorCode(ErrorCode_NotAcceptable, "Cannot send a response which is acceptable according to the Accept HTTP header");
    PrintErrorCode(ErrorCode_NullPointer, "Cannot handle a NULL pointer");
    PrintErrorCode(ErrorCode_DatabaseUnavailable, "The database is currently not available (probably a transient situation)");
    PrintErrorCode(ErrorCode_CanceledJob, "This job was canceled");
    PrintErrorCode(ErrorCode_BadGeometry, "Geometry error encountered in Stone");
    PrintErrorCode(ErrorCode_SslInitialization, "Cannot initialize SSL encryption, check out your certificates");
    PrintErrorCode(ErrorCode_SQLiteNotOpened, "SQLite: The database is not opened");
    PrintErrorCode(ErrorCode_SQLiteAlreadyOpened, "SQLite: Connection is already open");
    PrintErrorCode(ErrorCode_SQLiteCannotOpen, "SQLite: Unable to open the database");
    PrintErrorCode(ErrorCode_SQLiteStatementAlreadyUsed, "SQLite: This cached statement is already being referred to");
    PrintErrorCode(ErrorCode_SQLiteExecute, "SQLite: Cannot execute a command");
    PrintErrorCode(ErrorCode_SQLiteRollbackWithoutTransaction, "SQLite: Rolling back a nonexistent transaction (have you called Begin()?)");
    PrintErrorCode(ErrorCode_SQLiteCommitWithoutTransaction, "SQLite: Committing a nonexistent transaction");
    PrintErrorCode(ErrorCode_SQLiteRegisterFunction, "SQLite: Unable to register a function");
    PrintErrorCode(ErrorCode_SQLiteFlush, "SQLite: Unable to flush the database");
    PrintErrorCode(ErrorCode_SQLiteCannotRun, "SQLite: Cannot run a cached statement");
    PrintErrorCode(ErrorCode_SQLiteCannotStep, "SQLite: Cannot step over a cached statement");
    PrintErrorCode(ErrorCode_SQLiteBindOutOfRange, "SQLite: Bing a value while out of range (serious error)");
    PrintErrorCode(ErrorCode_SQLitePrepareStatement, "SQLite: Cannot prepare a cached statement");
    PrintErrorCode(ErrorCode_SQLiteTransactionAlreadyStarted, "SQLite: Beginning the same transaction twice");
    PrintErrorCode(ErrorCode_SQLiteTransactionCommit, "SQLite: Failure when committing the transaction");
    PrintErrorCode(ErrorCode_SQLiteTransactionBegin, "SQLite: Cannot start a transaction");
    PrintErrorCode(ErrorCode_DirectoryOverFile, "The directory to be created is already occupied by a regular file");
    PrintErrorCode(ErrorCode_FileStorageCannotWrite, "Unable to create a subdirectory or a file in the file storage");
    PrintErrorCode(ErrorCode_DirectoryExpected, "The specified path does not point to a directory");
    PrintErrorCode(ErrorCode_HttpPortInUse, "The TCP port of the HTTP server is privileged or already in use");
    PrintErrorCode(ErrorCode_DicomPortInUse, "The TCP port of the DICOM server is privileged or already in use");
    PrintErrorCode(ErrorCode_BadHttpStatusInRest, "This HTTP status is not allowed in a REST API");
    PrintErrorCode(ErrorCode_RegularFileExpected, "The specified path does not point to a regular file");
    PrintErrorCode(ErrorCode_PathToExecutable, "Unable to get the path to the executable");
    PrintErrorCode(ErrorCode_MakeDirectory, "Cannot create a directory");
    PrintErrorCode(ErrorCode_BadApplicationEntityTitle, "An application entity title (AET) cannot be empty or be longer than 16 characters");
    PrintErrorCode(ErrorCode_NoCFindHandler, "No request handler factory for DICOM C-FIND SCP");
    PrintErrorCode(ErrorCode_NoCMoveHandler, "No request handler factory for DICOM C-MOVE SCP");
    PrintErrorCode(ErrorCode_NoCStoreHandler, "No request handler factory for DICOM C-STORE SCP");
    PrintErrorCode(ErrorCode_NoApplicationEntityFilter, "No application entity filter");
    PrintErrorCode(ErrorCode_NoSopClassOrInstance, "DicomUserConnection: Unable to find the SOP class and instance");
    PrintErrorCode(ErrorCode_NoPresentationContext, "DicomUserConnection: No acceptable presentation context for modality");
    PrintErrorCode(ErrorCode_DicomFindUnavailable, "DicomUserConnection: The C-FIND command is not supported by the remote SCP");
    PrintErrorCode(ErrorCode_DicomMoveUnavailable, "DicomUserConnection: The C-MOVE command is not supported by the remote SCP");
    PrintErrorCode(ErrorCode_CannotStoreInstance, "Cannot store an instance");
    PrintErrorCode(ErrorCode_CreateDicomNotString, "Only string values are supported when creating DICOM instances");
    PrintErrorCode(ErrorCode_CreateDicomOverrideTag, "Trying to override a value inherited from a parent module");
    PrintErrorCode(ErrorCode_CreateDicomUseContent, "Use \"Content\" to inject an image into a new DICOM instance");
    PrintErrorCode(ErrorCode_CreateDicomNoPayload, "No payload is present for one instance in the series");
    PrintErrorCode(ErrorCode_CreateDicomUseDataUriScheme, "The payload of the DICOM instance must be specified according to Data URI scheme");
    PrintErrorCode(ErrorCode_CreateDicomBadParent, "Trying to attach a new DICOM instance to an inexistent resource");
    PrintErrorCode(ErrorCode_CreateDicomParentIsInstance, "Trying to attach a new DICOM instance to an instance (must be a series, study or patient)");
    PrintErrorCode(ErrorCode_CreateDicomParentEncoding, "Unable to get the encoding of the parent resource");
    PrintErrorCode(ErrorCode_UnknownModality, "Unknown modality");
    PrintErrorCode(ErrorCode_BadJobOrdering, "Bad ordering of filters in a job");
    PrintErrorCode(ErrorCode_JsonToLuaTable, "Cannot convert the given JSON object to a Lua table");
    PrintErrorCode(ErrorCode_CannotCreateLua, "Cannot create the Lua context");
    PrintErrorCode(ErrorCode_CannotExecuteLua, "Cannot execute a Lua command");
    PrintErrorCode(ErrorCode_LuaAlreadyExecuted, "Arguments cannot be pushed after the Lua function is executed");
    PrintErrorCode(ErrorCode_LuaBadOutput, "The Lua function does not give the expected number of outputs");
    PrintErrorCode(ErrorCode_NotLuaPredicate, "The Lua function is not a predicate (only true/false outputs allowed)");
    PrintErrorCode(ErrorCode_LuaReturnsNoString, "The Lua function does not return a string");
    PrintErrorCode(ErrorCode_StorageAreaAlreadyRegistered, "Another plugin has already registered a custom storage area");
    PrintErrorCode(ErrorCode_DatabaseBackendAlreadyRegistered, "Another plugin has already registered a custom database back-end");
    PrintErrorCode(ErrorCode_DatabaseNotInitialized, "Plugin trying to call the database during its initialization");
    PrintErrorCode(ErrorCode_SslDisabled, "Orthanc has been built without SSL support");
    PrintErrorCode(ErrorCode_CannotOrderSlices, "Unable to order the slices of the series");
    PrintErrorCode(ErrorCode_NoWorklistHandler, "No request handler factory for DICOM C-Find Modality SCP");
    PrintErrorCode(ErrorCode_AlreadyExistingTag, "Cannot override the value of a tag that already exists");
    PrintErrorCode(ErrorCode_NoStorageCommitmentHandler, "No request handler factory for DICOM N-ACTION SCP (storage commitment)");
    PrintErrorCode(ErrorCode_NoCGetHandler, "No request handler factory for DICOM C-GET SCP");
    PrintErrorCode(ErrorCode_UnsupportedMediaType, "Unsupported media type");
  }

  std::cout << std::endl;
}



#if ORTHANC_ENABLE_PLUGINS == 1
static void LoadPlugins(OrthancPlugins& plugins)
{
  std::list<std::string> pathList;

  {
    OrthancConfiguration::ReaderLock lock;
    lock.GetConfiguration().GetListOfStringsParameter(pathList, "Plugins");
  }

  for (std::list<std::string>::const_iterator
         it = pathList.begin(); it != pathList.end(); ++it)
  {
    std::string path;

    {
      OrthancConfiguration::ReaderLock lock;
      path = lock.GetConfiguration().InterpretStringParameterAsPath(*it);
    }

    LOG(WARNING) << "Loading plugin(s) from: " << path;
    plugins.GetManager().RegisterPlugin(path);
  }  
}
#endif



// Returns "true" if restart is required
static bool WaitForExit(ServerContext& context,
                        const OrthancRestApi& restApi)
{
  LOG(WARNING) << "Orthanc has started";

#if ORTHANC_ENABLE_PLUGINS == 1
  if (context.HasPlugins())
  {
    context.GetPlugins().SignalOrthancStarted();
  }
#endif

  context.GetLuaScripting().Start();
  context.GetLuaScripting().Execute("Initialize");

  bool restart;

  for (;;)
  {
    ServerBarrierEvent event = SystemToolbox::ServerBarrier(restApi.LeaveBarrierFlag());
    restart = restApi.IsResetRequestReceived();

    if (!restart && 
        event == ServerBarrierEvent_Reload)
    {
      // Handling of SIGHUP

      OrthancConfiguration::ReaderLock lock;
      if (lock.GetConfiguration().HasConfigurationChanged())
      {
        LOG(WARNING) << "A SIGHUP signal has been received, resetting Orthanc";
        Logging::Flush();
        restart = true;
        break;
      }
      else
      {
        LOG(WARNING) << "A SIGHUP signal has been received, but is ignored "
                     << "as the configuration has not changed on the disk";
        Logging::Flush();
        continue;
      }
    }
    else
    {
      break;
    }
  }

  context.GetLuaScripting().Execute("Finalize");
  context.GetLuaScripting().Stop();

#if ORTHANC_ENABLE_PLUGINS == 1
  if (context.HasPlugins())
  {
    context.GetPlugins().SignalOrthancStopped();
  }
#endif

  if (restart)
  {
    LOG(WARNING) << "Reset request received, restarting Orthanc";
  }

  // We're done
  LOG(WARNING) << "Orthanc is stopping";

  return restart;
}



static bool StartHttpServer(ServerContext& context,
                            const OrthancRestApi& restApi,
                            OrthancPlugins* plugins)
{
  bool httpServerEnabled;

  {
    OrthancConfiguration::ReaderLock lock;
    httpServerEnabled = lock.GetConfiguration().GetBooleanParameter("HttpServerEnabled", true);
  }

  if (!httpServerEnabled)
  {
    LOG(WARNING) << "The HTTP server is disabled";
    return WaitForExit(context, restApi);
  }
  else
  {
    MyIncomingHttpRequestFilter httpFilter(context, plugins);
    HttpServer httpServer;
    bool httpDescribeErrors;

#if ORTHANC_ENABLE_MONGOOSE == 1
    const bool defaultKeepAlive = false;
#elif ORTHANC_ENABLE_CIVETWEB == 1
    const bool defaultKeepAlive = true;
#else
#  error "Either Mongoose or Civetweb must be enabled to compile this file"
#endif
  
    {
      OrthancConfiguration::ReaderLock lock;
      
      httpDescribeErrors = lock.GetConfiguration().GetBooleanParameter("HttpDescribeErrors", true);
  
      // HTTP server
      httpServer.SetThreadsCount(lock.GetConfiguration().GetUnsignedIntegerParameter("HttpThreadsCount", 50));
      httpServer.SetPortNumber(lock.GetConfiguration().GetUnsignedIntegerParameter("HttpPort", 8042));
      httpServer.SetRemoteAccessAllowed(lock.GetConfiguration().GetBooleanParameter("RemoteAccessAllowed", false));
      httpServer.SetKeepAliveEnabled(lock.GetConfiguration().GetBooleanParameter("KeepAlive", defaultKeepAlive));
      httpServer.SetHttpCompressionEnabled(lock.GetConfiguration().GetBooleanParameter("HttpCompressionEnabled", true));
      httpServer.SetTcpNoDelay(lock.GetConfiguration().GetBooleanParameter("TcpNoDelay", true));
      httpServer.SetRequestTimeout(lock.GetConfiguration().GetUnsignedIntegerParameter("HttpRequestTimeout", 30));

      // Let's assume that the HTTP server is secure
      context.SetHttpServerSecure(true);

      bool authenticationEnabled;
      if (lock.GetConfiguration().LookupBooleanParameter(authenticationEnabled, "AuthenticationEnabled"))
      {
        httpServer.SetAuthenticationEnabled(authenticationEnabled);

        if (httpServer.IsRemoteAccessAllowed() &&
            !authenticationEnabled)
        {
          LOG(WARNING) << "====> Remote access is enabled while user authentication is explicitly disabled, "
                       << "your setup is POSSIBLY INSECURE <====";
          context.SetHttpServerSecure(false);
        }
      }
      else if (httpServer.IsRemoteAccessAllowed())
      {
        // Starting with Orthanc 1.5.8, it is impossible to enable
        // remote access without having explicitly disabled user
        // authentication.
        LOG(WARNING) << "Remote access is allowed but \"AuthenticationEnabled\" is not in the configuration, "
                     << "automatically enabling HTTP authentication for security";          
        httpServer.SetAuthenticationEnabled(true);
      }
      else
      {
        // If Orthanc only listens on the localhost, it is OK to have
        // "AuthenticationEnabled" disabled
        httpServer.SetAuthenticationEnabled(false);
      }

      bool hasUsers = lock.GetConfiguration().SetupRegisteredUsers(httpServer);

      if (httpServer.IsAuthenticationEnabled() &&
          !hasUsers)
      {
        if (httpServer.IsRemoteAccessAllowed())
        {
          /**
           * Starting with Orthanc 1.5.8, if no user is explicitly
           * defined while remote access is allowed, we create a
           * default user, and Orthanc Explorer shows a warning
           * message about an "Insecure setup". This convention is
           * used in Docker images "jodogne/orthanc",
           * "jodogne/orthanc-plugins" and "osimis/orthanc".
           **/
          LOG(WARNING) << "====> HTTP authentication is enabled, but no user is declared. "
                       << "Creating a default user: Review your configuration option \"RegisteredUsers\". "
                       << "Your setup is INSECURE <====";

          context.SetHttpServerSecure(false);

          // This is the username/password of the default user in Orthanc.
          httpServer.RegisterUser("orthanc", "orthanc");
        }
        else
        {
          LOG(WARNING) << "HTTP authentication is enabled, but no user is declared, "
                       << "check the value of configuration option \"RegisteredUsers\"";
        }
      }
      
      if (lock.GetConfiguration().GetBooleanParameter("SslEnabled", false))
      {
        std::string certificate = lock.GetConfiguration().InterpretStringParameterAsPath(
          lock.GetConfiguration().GetStringParameter("SslCertificate", "certificate.pem"));
        httpServer.SetSslEnabled(true);
        httpServer.SetSslCertificate(certificate.c_str());
      }
      else
      {
        httpServer.SetSslEnabled(false);
      }

      if (lock.GetConfiguration().GetBooleanParameter("SslVerifyPeers", false))
      {
        std::string trustedClientCertificates = lock.GetConfiguration().InterpretStringParameterAsPath(
          lock.GetConfiguration().GetStringParameter("SslTrustedClientCertificates", "trustedCertificates.pem"));
        httpServer.SetSslVerifyPeers(true);
        httpServer.SetSslTrustedClientCertificates(trustedClientCertificates.c_str());
      }
      else
      {
        httpServer.SetSslVerifyPeers(false);
      }

      if (lock.GetConfiguration().GetBooleanParameter("ExecuteLuaEnabled", false))
      {
        context.SetExecuteLuaEnabled(true);
        LOG(WARNING) << "====> Remote LUA script execution is enabled.  Review your configuration option \"ExecuteLuaEnabled\". "
                     << "Your setup is POSSIBLY INSECURE <====";
      }
      else
      {
        context.SetExecuteLuaEnabled(false);
        LOG(WARNING) << "Remote LUA script execution is disabled";
      }
    }

    MyHttpExceptionFormatter exceptionFormatter(httpDescribeErrors, plugins);
        
    httpServer.SetIncomingHttpRequestFilter(httpFilter);
    httpServer.SetHttpExceptionFormatter(exceptionFormatter);
    httpServer.Register(context.GetHttpHandler());

    {
      UriComponents root;  // TODO
      root.push_back("a");
      root.push_back("b");
      //httpServer.Register(root, new WebDavStorage(true));
      //httpServer.Register(root, new DummyBucket(context, true));
      httpServer.Register(root, new DummyBucket2(context));
    }

    if (httpServer.GetPortNumber() < 1024)
    {
      LOG(WARNING) << "The HTTP port is privileged (" 
                   << httpServer.GetPortNumber() << " is below 1024), "
                   << "make sure you run Orthanc as root/administrator";
    }

    httpServer.Start();
  
    bool restart = WaitForExit(context, restApi);

    httpServer.Stop();
    LOG(WARNING) << "    HTTP server has stopped";

    return restart;
  }
}


static bool StartDicomServer(ServerContext& context,
                             const OrthancRestApi& restApi,
                             OrthancPlugins* plugins)
{
  bool dicomServerEnabled;

  {
    OrthancConfiguration::ReaderLock lock;
    dicomServerEnabled = lock.GetConfiguration().GetBooleanParameter("DicomServerEnabled", true);
  }

  if (!dicomServerEnabled)
  {
    LOG(WARNING) << "The DICOM server is disabled";
    return StartHttpServer(context, restApi, plugins);
  }
  else
  {
    MyDicomServerFactory serverFactory(context);
    OrthancApplicationEntityFilter dicomFilter(context);
    ModalitiesFromConfiguration modalities;
  
    // Setup the DICOM server  
    DicomServer dicomServer;
    dicomServer.SetRemoteModalities(modalities);
    dicomServer.SetStoreRequestHandlerFactory(serverFactory);
    dicomServer.SetMoveRequestHandlerFactory(serverFactory);
    dicomServer.SetGetRequestHandlerFactory(serverFactory);
    dicomServer.SetFindRequestHandlerFactory(serverFactory);
    dicomServer.SetStorageCommitmentRequestHandlerFactory(serverFactory);

    {
      OrthancConfiguration::ReaderLock lock;
      dicomServer.SetCalledApplicationEntityTitleCheck(lock.GetConfiguration().GetBooleanParameter("DicomCheckCalledAet", false));
      dicomServer.SetAssociationTimeout(lock.GetConfiguration().GetUnsignedIntegerParameter("DicomScpTimeout", 30));
      dicomServer.SetPortNumber(lock.GetConfiguration().GetUnsignedIntegerParameter("DicomPort", 4242));
      dicomServer.SetApplicationEntityTitle(lock.GetConfiguration().GetOrthancAET());
    }

#if ORTHANC_ENABLE_PLUGINS == 1
    if (plugins != NULL)
    {
      if (plugins->HasWorklistHandler())
      {
        dicomServer.SetWorklistRequestHandlerFactory(*plugins);
      }

      if (plugins->HasFindHandler())
      {
        dicomServer.SetFindRequestHandlerFactory(*plugins);
      }

      if (plugins->HasMoveHandler())
      {
        dicomServer.SetMoveRequestHandlerFactory(*plugins);
      }
    }
#endif

    dicomServer.SetApplicationEntityFilter(dicomFilter);

    if (dicomServer.GetPortNumber() < 1024)
    {
      LOG(WARNING) << "The DICOM port is privileged (" 
                   << dicomServer.GetPortNumber() << " is below 1024), "
                   << "make sure you run Orthanc as root/administrator";
    }

    dicomServer.Start();
    LOG(WARNING) << "DICOM server listening with AET " << dicomServer.GetApplicationEntityTitle() 
                 << " on port: " << dicomServer.GetPortNumber();

    bool restart = false;
    ErrorCode error = ErrorCode_Success;

    try
    {
      restart = StartHttpServer(context, restApi, plugins);
    }
    catch (OrthancException& e)
    {
      error = e.GetErrorCode();
    }

    dicomServer.Stop();
    LOG(WARNING) << "    DICOM server has stopped";

    serverFactory.Done();

    if (error != ErrorCode_Success)
    {
      throw OrthancException(error);
    }

    return restart;
  }
}


static bool ConfigureHttpHandler(ServerContext& context,
                                 OrthancPlugins *plugins,
                                 bool loadJobsFromDatabase)
{
#if ORTHANC_ENABLE_PLUGINS == 1
  // By order of priority, first apply the "plugins" layer, so that
  // plugins can overwrite the built-in REST API of Orthanc
  if (plugins)
  {
    assert(context.HasPlugins());
    context.GetHttpHandler().Register(*plugins, false);
  }
#endif
  
  // Secondly, apply the "static resources" layer
#if ORTHANC_STANDALONE == 1
  EmbeddedResourceHttpHandler staticResources("/app", ServerResources::ORTHANC_EXPLORER);
#else
  FilesystemHttpHandler staticResources("/app", ORTHANC_PATH "/OrthancExplorer");
#endif

  context.GetHttpHandler().Register(staticResources, false);

  // Thirdly, consider the built-in REST API of Orthanc
  OrthancRestApi restApi(context);
  context.GetHttpHandler().Register(restApi, true);

  context.SetupJobsEngine(false /* not running unit tests */, loadJobsFromDatabase);

  bool restart = StartDicomServer(context, restApi, plugins);

  context.Stop();

  return restart;
}


static void UpgradeDatabase(IDatabaseWrapper& database,
                            IStorageArea& storageArea)
{
  // Upgrade the schema of the database, if needed
  unsigned int currentVersion = database.GetDatabaseVersion();

  LOG(WARNING) << "Starting the upgrade of the database schema";
  LOG(WARNING) << "Current database version: " << currentVersion;
  LOG(WARNING) << "Database version expected by Orthanc: " << ORTHANC_DATABASE_VERSION;
  
  if (currentVersion == ORTHANC_DATABASE_VERSION)
  {
    LOG(WARNING) << "No upgrade is needed, start Orthanc without the \"--upgrade\" argument";
    return;
  }

  if (currentVersion > ORTHANC_DATABASE_VERSION)
  {
    throw OrthancException(ErrorCode_IncompatibleDatabaseVersion,
                           "The version of the database schema (" +
                           boost::lexical_cast<std::string>(currentVersion) +
                           ") is too recent for this version of Orthanc. Please upgrade Orthanc.");
  }

  LOG(WARNING) << "Upgrading the database from schema version "
               << currentVersion << " to " << ORTHANC_DATABASE_VERSION;

  try
  {
    database.Upgrade(ORTHANC_DATABASE_VERSION, storageArea);
  }
  catch (OrthancException&)
  {
    LOG(ERROR) << "Unable to run the automated upgrade, please use the replication instructions: "
               << "http://book.orthanc-server.com/users/replication.html";
    throw;
  }
    
  // Sanity check
  currentVersion = database.GetDatabaseVersion();
  if (ORTHANC_DATABASE_VERSION != currentVersion)
  {
    throw OrthancException(ErrorCode_IncompatibleDatabaseVersion,
                           "The database schema was not properly upgraded, it is still at version " +
                           boost::lexical_cast<std::string>(currentVersion));
  }
  else
  {
    LOG(WARNING) << "The database schema was successfully upgraded, "
                 << "you can now start Orthanc without the \"--upgrade\" argument";
  }
}



namespace
{
  class ServerContextConfigurator : public boost::noncopyable
  {
  private:
    ServerContext&   context_;
    OrthancPlugins*  plugins_;

  public:
    ServerContextConfigurator(ServerContext& context,
                              OrthancPlugins* plugins) :
      context_(context),
      plugins_(plugins)
    {
      {
        OrthancConfiguration::WriterLock lock;
        lock.GetConfiguration().SetServerIndex(context.GetIndex());
      }

#if ORTHANC_ENABLE_PLUGINS == 1
      if (plugins_ != NULL)
      {
        plugins_->SetServerContext(context_);
        context_.SetPlugins(*plugins_);
      }
#endif
    }

    ~ServerContextConfigurator()
    {
      {
        OrthancConfiguration::WriterLock lock;
        lock.GetConfiguration().ResetServerIndex();
      }

#if ORTHANC_ENABLE_PLUGINS == 1
      if (plugins_ != NULL)
      {
        plugins_->ResetServerContext();
        context_.ResetPlugins();
      }
#endif
    }
  };
}


static bool ConfigureServerContext(IDatabaseWrapper& database,
                                   IStorageArea& storageArea,
                                   OrthancPlugins *plugins,
                                   bool loadJobsFromDatabase)
{
  size_t maxCompletedJobs;
  
  {
    OrthancConfiguration::ReaderLock lock;

    // These configuration options must be set before creating the
    // ServerContext, otherwise the possible Lua scripts will not be
    // able to properly issue HTTP/HTTPS queries
    HttpClient::ConfigureSsl(lock.GetConfiguration().GetBooleanParameter("HttpsVerifyPeers", true),
                             lock.GetConfiguration().InterpretStringParameterAsPath
                             (lock.GetConfiguration().GetStringParameter("HttpsCACertificates", "")));
    HttpClient::SetDefaultVerbose(lock.GetConfiguration().GetBooleanParameter("HttpVerbose", false));

    // The value "0" below makes the class HttpClient use its default
    // value (DEFAULT_HTTP_TIMEOUT = 60 seconds in Orthanc 1.5.7)
    HttpClient::SetDefaultTimeout(lock.GetConfiguration().GetUnsignedIntegerParameter("HttpTimeout", 0));
    
    HttpClient::SetDefaultProxy(lock.GetConfiguration().GetStringParameter("HttpProxy", ""));
    
    DicomAssociationParameters::SetDefaultTimeout(lock.GetConfiguration().GetUnsignedIntegerParameter("DicomScuTimeout", 10));

    maxCompletedJobs = lock.GetConfiguration().GetUnsignedIntegerParameter("JobsHistorySize", 10);

    if (maxCompletedJobs == 0)
    {
      LOG(WARNING) << "Setting option \"JobsHistorySize\" to zero is not recommended";
    }
  }
  
  ServerContext context(database, storageArea, false /* not running unit tests */, maxCompletedJobs);

  {
    OrthancConfiguration::ReaderLock lock;

    context.SetCompressionEnabled(lock.GetConfiguration().GetBooleanParameter("StorageCompression", false));
    context.SetStoreMD5ForAttachments(lock.GetConfiguration().GetBooleanParameter("StoreMD5ForAttachments", true));

    // New option in Orthanc 1.4.2
    context.SetOverwriteInstances(lock.GetConfiguration().GetBooleanParameter("OverwriteInstances", false));

    try
    {
      context.GetIndex().SetMaximumPatientCount(lock.GetConfiguration().GetUnsignedIntegerParameter("MaximumPatientCount", 0));
    }
    catch (...)
    {
      context.GetIndex().SetMaximumPatientCount(0);
    }

    try
    {
      uint64_t size = lock.GetConfiguration().GetUnsignedIntegerParameter("MaximumStorageSize", 0);
      context.GetIndex().SetMaximumStorageSize(size * 1024 * 1024);
    }
    catch (...)
    {
      context.GetIndex().SetMaximumStorageSize(0);
    }
  }

  {
    ServerContextConfigurator configurator(context, plugins);

    {
      OrthancConfiguration::WriterLock lock;
      lock.GetConfiguration().LoadModalitiesAndPeers();
    }

    return ConfigureHttpHandler(context, plugins, loadJobsFromDatabase);
  }
}


static bool ConfigureDatabase(IDatabaseWrapper& database,
                              IStorageArea& storageArea,
                              OrthancPlugins *plugins,
                              bool upgradeDatabase,
                              bool loadJobsFromDatabase)
{
  database.Open();

  unsigned int currentVersion = database.GetDatabaseVersion();

  if (upgradeDatabase)
  {
    UpgradeDatabase(database, storageArea);
    return false;  // Stop and don't restart Orthanc (cf. issue 29)
  }
  else if (currentVersion != ORTHANC_DATABASE_VERSION)
  {
    throw OrthancException(ErrorCode_IncompatibleDatabaseVersion,
                           "The database schema must be upgraded from version " +
                           boost::lexical_cast<std::string>(currentVersion) + " to " +
                           boost::lexical_cast<std::string>(ORTHANC_DATABASE_VERSION) +
                           ": Please run Orthanc with the \"--upgrade\" argument");
  }

  bool success = ConfigureServerContext
    (database, storageArea, plugins, loadJobsFromDatabase);

  database.Close();

  return success;
}


static bool ConfigurePlugins(int argc, 
                             char* argv[],
                             bool upgradeDatabase,
                             bool loadJobsFromDatabase)
{
  std::unique_ptr<IDatabaseWrapper>  databasePtr;
  std::unique_ptr<IStorageArea>  storage;

#if ORTHANC_ENABLE_PLUGINS == 1
  OrthancPlugins plugins;
  plugins.SetCommandLineArguments(argc, argv);
  LoadPlugins(plugins);

  IDatabaseWrapper* database = NULL;
  if (plugins.HasDatabaseBackend())
  {
    LOG(WARNING) << "Using a custom database from plugins";
    database = &plugins.GetDatabaseBackend();
  }
  else
  {
    databasePtr.reset(CreateDatabaseWrapper());
    database = databasePtr.get();
  }

  if (plugins.HasStorageArea())
  {
    LOG(WARNING) << "Using a custom storage area from plugins";
    storage.reset(plugins.CreateStorageArea());
  }
  else
  {
    storage.reset(CreateStorageArea());
  }

  assert(database != NULL);
  assert(storage.get() != NULL);

  return ConfigureDatabase(*database, *storage, &plugins,
                           upgradeDatabase, loadJobsFromDatabase);

#elif ORTHANC_ENABLE_PLUGINS == 0
  // The plugins are disabled

  databasePtr.reset(CreateDatabaseWrapper());
  storage.reset(CreateStorageArea());

  assert(databasePtr.get() != NULL);
  assert(storage.get() != NULL);

  return ConfigureDatabase(*databasePtr, *storage, NULL,
                           upgradeDatabase, loadJobsFromDatabase);

#else
#  error The macro ORTHANC_ENABLE_PLUGINS must be set to 0 or 1
#endif
}


static bool StartOrthanc(int argc, 
                         char* argv[],
                         bool upgradeDatabase,
                         bool loadJobsFromDatabase)
{
  return ConfigurePlugins(argc, argv, upgradeDatabase, loadJobsFromDatabase);
}


static bool DisplayPerformanceWarning()
{
  (void) DisplayPerformanceWarning;   // Disable warning about unused function
  LOG(WARNING) << "Performance warning: Non-release build, runtime debug assertions are turned on";
  return true;
}


int main(int argc, char* argv[]) 
{
  Logging::Initialize();

  bool upgradeDatabase = false;
  bool loadJobsFromDatabase = true;
  const char* configurationFile = NULL;


  /**
   * Parse the command-line options.
   **/ 

  for (int i = 1; i < argc; i++)
  {
    std::string argument(argv[i]); 

    if (argument.empty())
    {
      // Ignore empty arguments
    }
    else if (argument[0] != '-')
    {
      if (configurationFile != NULL)
      {
        LOG(ERROR) << "More than one configuration path were provided on the command line, aborting";
        return -1;
      }
      else
      {
        // Use the first argument that does not start with a "-" as
        // the configuration file

        // TODO WHAT IS THE ENCODING?
        configurationFile = argv[i];
      }
    }
    else if (argument == "--errors")
    {
      PrintErrors(argv[0]);
      return 0;
    }
    else if (argument == "--help")
    {
      PrintHelp(argv[0]);
      return 0;
    }
    else if (argument == "--version")
    {
      PrintVersion(argv[0]);
      return 0;
    }
    else if (argument == "--verbose")
    {
      Logging::EnableInfoLevel(true);
    }
    else if (argument == "--trace")
    {
      Logging::EnableTraceLevel(true);
    }
    else if (boost::starts_with(argument, "--logdir="))
    {
      // TODO WHAT IS THE ENCODING?
      std::string directory = argument.substr(9);

      try
      {
        Logging::SetTargetFolder(directory);
      }
      catch (OrthancException&)
      {
        LOG(ERROR) << "The directory where to store the log files (" 
                   << directory << ") is inexistent, aborting.";
        return -1;
      }
    }
    else if (boost::starts_with(argument, "--logfile="))
    {
      // TODO WHAT IS THE ENCODING?
      std::string file = argument.substr(10);

      try
      {
        Logging::SetTargetFile(file);
      }
      catch (OrthancException&)
      {
        LOG(ERROR) << "Cannot write to the specified log file (" 
                   << file << "), aborting.";
        return -1;
      }
    }
    else if (argument == "--upgrade")
    {
      upgradeDatabase = true;
    }
    else if (argument == "--no-jobs")
    {
      loadJobsFromDatabase = false;
    }
    else if (boost::starts_with(argument, "--config="))
    {
      // TODO WHAT IS THE ENCODING?
      std::string configurationSample;
      GetFileResource(configurationSample, ServerResources::CONFIGURATION_SAMPLE);

#if defined(_WIN32)
      // Replace UNIX newlines with DOS newlines 
      boost::replace_all(configurationSample, "\n", "\r\n");
#endif

      std::string target = argument.substr(9);

      try
      {
        if (target == "-")
        {
          // New in 1.5.8: Print to stdout
          std::cout << configurationSample;
        }
        else
        {
          SystemToolbox::WriteFile(configurationSample, target);
        }
        return 0;
      }
      catch (OrthancException&)
      {
        LOG(ERROR) << "Cannot write sample configuration as file \"" << target << "\"";
        return -1;
      }
    }
    else
    {
      LOG(WARNING) << "Option unsupported by the core of Orthanc: " << argument;
    }
  }


  /**
   * Launch Orthanc.
   **/

  {
    std::string version(ORTHANC_VERSION);

    if (std::string(ORTHANC_VERSION) == "mainline")
    {
      try
      {
        boost::filesystem::path exe(SystemToolbox::GetPathToExecutable());
        std::time_t creation = boost::filesystem::last_write_time(exe);
        boost::posix_time::ptime converted(boost::posix_time::from_time_t(creation));
        version += " (" + boost::posix_time::to_iso_string(converted) + ")";
      }
      catch (...)
      {
      }
    }

    LOG(WARNING) << "Orthanc version: " << version;
    assert(DisplayPerformanceWarning());

    std::string s = "Architecture: ";
    if (sizeof(void*) == 4)
    {
      s += "32-bit, ";
    }
    else if (sizeof(void*) == 8)
    {
      s += "64-bit, ";
    }
    else
    {
      s += "unsupported pointer size, ";
    }

    switch (Toolbox::DetectEndianness())
    {
      case Endianness_Little:
        s += "little endian";
        break;
      
      case Endianness_Big:
        s += "big endian";
        break;
      
      default:
        s += "unsupported endianness";
        break;
    }
    
    LOG(INFO) << s;
  }

  int status = 0;
  try
  {
    for (;;)
    {
      OrthancInitialize(configurationFile);

      bool restart = StartOrthanc(argc, argv, upgradeDatabase, loadJobsFromDatabase);
      if (restart)
      {
        OrthancFinalize();
        LOG(WARNING) << "Logging system is resetting";
        Logging::Reset();
      }
      else
      {
        break;
      }
    }
  }
  catch (const OrthancException& e)
  {
    LOG(ERROR) << "Uncaught exception, stopping now: [" << e.What() << "] (code " << e.GetErrorCode() << ")";
#if defined(_WIN32)
    if (e.GetErrorCode() >= ErrorCode_START_PLUGINS)
    {
      status = static_cast<int>(ErrorCode_Plugin);
    }
    else
    {
      status = static_cast<int>(e.GetErrorCode());
    }

#else
    status = -1;
#endif
  }
  catch (const std::exception& e) 
  {
    LOG(ERROR) << "Uncaught exception, stopping now: [" << e.what() << "]";
    status = -1;
  }
  catch (const std::string& s) 
  {
    LOG(ERROR) << "Uncaught exception, stopping now: [" << s << "]";
    status = -1;
  }
  catch (...)
  {
    LOG(ERROR) << "Native exception, stopping now. Check your plugins, if any.";
    status = -1;
  }

  LOG(WARNING) << "Orthanc has stopped";

  OrthancFinalize();

  return status;
}