//----------------------------------------------------------------------
// Includes
//----------------------------------------------------------------------
#include "MantidKernel/ConfigService.h"
#include "MantidKernel/MantidVersion.h"
#include "MantidKernel/Support.h"
#include "MantidKernel/Logger.h"
#include "MantidKernel/FilterChannel.h"
#include "MantidKernel/SignalChannel.h"
#include "MantidKernel/Exception.h"
#include "MantidKernel/FacilityInfo.h"

#include "Poco/Util/LoggingConfigurator.h"
#include "Poco/Util/SystemConfiguration.h"
#include "Poco/Util/PropertyFileConfiguration.h"
#include "Poco/LoggingFactory.h"
#include "Poco/Path.h"
#include "Poco/File.h"
#include "Poco/StringTokenizer.h"
#include "Poco/DOM/DOMParser.h"
#include "Poco/DOM/Document.h"
#include "Poco/DOM/Element.h"
#include "Poco/DOM/NodeList.h"
#include "Poco/Notification.h"
#include "Poco/Environment.h"

#include <fstream>
#include <sstream>
#include <iostream>
#include <string>

namespace Mantid
{
namespace Kernel
{

/** Inner templated class to wrap the poco library objects that have protected
 *  destructors and expose them as public.
 */
template<typename T>
class ConfigServiceImpl::WrappedObject: public T
{
public:
  /// The template type of class that is being wrapped
  typedef T element_type;
  /// Simple constructor
  WrappedObject() :
    T()
  {
    m_pPtr = static_cast<T*> (this);
  }

  /** Constructor with a class to wrap
   *  @param F The object to wrap
   */
  template<typename Field>
  WrappedObject(Field& F) :
    T(F)
  {
    m_pPtr = static_cast<T*> (this);
  }

  /// Copy constructor
  WrappedObject(const WrappedObject<T>& A) :
    T(A)
  {
    m_pPtr = static_cast<T*> (this);
  }

  /// Virtual destructor
  virtual ~WrappedObject()
  {
  }

  /// Overloaded * operator returns the wrapped object pointer
  const T& operator*() const
  {
    return *m_pPtr;
  }
  /// Overloaded * operator returns the wrapped object pointer
  T& operator*()
  {
    return m_pPtr;
  }
  /// Overloaded -> operator returns the wrapped object pointer
  const T* operator->() const
  {
    return m_pPtr;
  }
  /// Overloaded -> operator returns the wrapped object pointer
  T* operator->()
  {
    return m_pPtr;
  }

private:
  /// Private pointer to the wrapped class
  T* m_pPtr;
};

//Back to the ConfigService class itself...

//-------------------------------
// Private member functions
//-------------------------------

/// Private constructor for singleton class
ConfigServiceImpl::ConfigServiceImpl() :
  m_pConf(NULL), m_pSysConfig(NULL), g_log(Logger::get("ConfigService")), m_changed_keys(),
      m_ConfigPaths(), m_AbsolutePaths(), m_strBaseDir(""), m_PropertyString(""),
      m_properties_file_name("Mantid.properties"),
      m_user_properties_file_name("Mantid.user.properties"), m_DataSearchDirs(), m_instr_prefixes()
{
  //getting at system details
  m_pSysConfig = new WrappedObject<Poco::Util::SystemConfiguration> ;
  m_pConf = 0;

  //Register the FilterChannel with the Poco logging factory
  Poco::LoggingFactory::defaultFactory().registerChannelClass("FilterChannel", new Poco::Instantiator<
      Poco::FilterChannel, Poco::Channel>);

  //Register the SignalChannel with the Poco logging factory
  Poco::LoggingFactory::defaultFactory().registerChannelClass("SignalChannel", new Poco::Instantiator<
      Poco::SignalChannel, Poco::Channel>);

  // Define a directory that serves as the 'application directory'. This is where we expect to find the Mantid.properties file
  // It cannot simply be the current directory since the application may be called from a different place, .i.e.
  // on Linux where the bin directory is in the path and the app is run from a different location.
  // We have two scenarios:
  //  1) The framework is compiled into an executable and its directory is then considered as the base or,
  //  2) The framework is in a stand-alone library and is created from within another executing application
  //     e.g. Python or Matlab (only two at the moment). We can only use the current directory here as there
  //     is no programmatic way of determing where the library that contains this class is.

  // A MANTID environmental variable might solve all of this??

  std::string callingApplication = Poco::Path(getPathToExecutable()).getFileName();
  // the cases used in the names varies on different systems so we do this case insensitive
  std::transform(callingApplication.begin(), callingApplication.end(), callingApplication.begin(),
      tolower);
  if (callingApplication.find("python") != std::string::npos || callingApplication.find("matlab")
      != std::string::npos)
  {
    if (Poco::Environment::has("MANTIDPATH"))
    {
      // Here we have to follow the convention of the rest of this code and add a trailing slash.
      // Note: adding it to the MANTIDPATH itself will make other parts of the code crash.
      m_strBaseDir = Poco::Environment::get("MANTIDPATH") + "/";
    }
    else
      m_strBaseDir = Poco::Path::current();
  }
  else
  {
    m_strBaseDir = Mantid::Kernel::getDirectoryOfExecutable();
  }

  //Fill the list of possible relative path keys that may require conversion to absolute paths
  m_ConfigPaths.insert(std::make_pair("plugins.directory", true));
  m_ConfigPaths.insert(std::make_pair("mantidqt.plugins.directory", true));
  m_ConfigPaths.insert(std::make_pair("instrumentDefinition.directory", true));
  m_ConfigPaths.insert(std::make_pair("parameterDefinition.directory", true));
  m_ConfigPaths.insert(std::make_pair("requiredpythonscript.directories", true));
  m_ConfigPaths.insert(std::make_pair("pythonscripts.directory", true));
  m_ConfigPaths.insert(std::make_pair("pythonscripts.directories", true));
  m_ConfigPaths.insert(std::make_pair("ManagedWorkspace.FilePath", true));
  m_ConfigPaths.insert(std::make_pair("defaultsave.directory", false));
  m_ConfigPaths.insert(std::make_pair("datasearch.directories", true));
  m_ConfigPaths.insert(std::make_pair("pythonalgorithms.directories", true));
  m_ConfigPaths.insert(std::make_pair("icatDownload.directory", true));

  //attempt to load the default properties file that resides in the directory of the executable
  updateConfig(getBaseDir() + m_properties_file_name, false, false);
  //and then append the user properties
  updateConfig(getUserFilename(), true, true);

  updateFacilities();

  g_log.debug() << "ConfigService created." << std::endl;
  g_log.debug() << "Configured base directory of application as " << getBaseDir() << std::endl;
  g_log.information() << "This is Mantid Version " << MANTID_VERSION << std::endl;
}

/** Private Destructor
 *  Prevents client from calling 'delete' on the pointer handed out by Instance
 */
ConfigServiceImpl::~ConfigServiceImpl()
{
  //std::cerr << "ConfigService destroyed." << std::endl;
  Kernel::Logger::shutdown();
  delete m_pSysConfig;
  delete m_pConf; // potential double delete???
  for (std::vector<FacilityInfo*>::iterator it = m_facilities.begin(); it != m_facilities.end(); ++it)
  {
    delete *it;
  }
  m_facilities.clear();
}

/** Loads the config file provided.
 *  If the file contains logging setup instructions then these will be used to setup the logging framework.
 *
 *  @param filename The filename and optionally path of the file to load
 *  @param append If false (default) then any previous configuration is discarded, otherwise the new keys are added, and repeated keys will override existing ones.
 */
void ConfigServiceImpl::loadConfig(const std::string& filename, const bool append)
{
  delete m_pConf;
  if (!append)
  {
    //remove the previous property string
    m_PropertyString = "";
  }

  try
  {
    //slurp in entire file
    std::string temp;
    bool good = readFile(filename, temp);

    // check if we have failed to open the file
    if ((!good) || (temp == ""))
    {
      if (filename == getOutputDir() + m_user_properties_file_name)
      {
        //write out a fresh file
        createUserPropertiesFile();
      }
      else
      {
        throw Exception::FileError("Cannot open file", filename);
      }
    }

    //store the property string
    if ((append) && (m_PropertyString != ""))
    {
      m_PropertyString = m_PropertyString + "\n" + temp;
    }
    else
    {
      m_PropertyString = temp;
    }

  } catch (std::exception& e)
  {
    //there was a problem loading the file - it probably is not there
    std::cerr << "Problem loading the configuration file " << filename << " " << e.what() << std::endl;

    if (!append)
    {
      // if we have no property values then take the default
      m_PropertyString = defaultConfig();
    }
  }

  //use the cached property string to initialise the POCO property file
  std::istringstream istr(m_PropertyString);
  m_pConf = new WrappedObject<Poco::Util::PropertyFileConfiguration> (istr);
}

/**
 * Read a file and place its contents into the given string
 * @param filename The filename of the file to read
 * @param contents The file contents will be placed here
 * @returns A boolean indicating whether opening the file was successful
 */
bool ConfigServiceImpl::readFile(const std::string& filename, std::string & contents) const
{
  std::ifstream propFile(filename.c_str(), std::ios::in);
  bool good = propFile.good();
  if (!good)
  {
    contents = "";
    propFile.close();
    return good;
  }

  //slurp in entire file - extremely unlikely delimiter used as an alternate to \n
  contents.clear();
  getline(propFile, contents, '`');
  propFile.close();
  return good;
}

/// Configures the Poco logging and starts it up
void ConfigServiceImpl::configureLogging()
{
  try
  {
    //Ensure that the logging directory exists
    Poco::Path logpath(getString("logging.channels.fileChannel.path"));
    if (logpath.toString().empty() || getOutputDir() != getBaseDir())
    {
      std::string logfile = getOutputDir() + "mantid.log";
      logpath.assign(logfile);
      m_pConf->setString("logging.channels.fileChannel.path", logfile);
    }
    //make this path point to the parent directory and create it if it does not exist
    logpath.makeParent();
    if (!logpath.toString().empty())
    {
      Poco::File(logpath).createDirectory();
    }
    //configure the logging framework
    Poco::Util::LoggingConfigurator configurator;
    configurator.configure(m_pConf);
  } catch (std::exception& e)
  {
    std::cerr << "Trouble configuring the logging framework " << e.what() << std::endl;
  }

}

/**
 * Searches the stored list for keys that have been loaded from the config file and may contain
 * relative paths. Any it find are converted to absolute paths and stored separately
 */
void ConfigServiceImpl::convertRelativeToAbsolute()
{
  if (m_ConfigPaths.empty())
    return;

  std::string execdir(getBaseDir());
  m_AbsolutePaths.clear();

  std::map<std::string, bool>::const_iterator send = m_ConfigPaths.end();
  for (std::map<std::string, bool>::const_iterator sitr = m_ConfigPaths.begin(); sitr != send; ++sitr)
  {
    std::string key = sitr->first;
    if (!m_pConf->hasProperty(key))
      continue;

    std::string value(m_pConf->getString(key));
    value = makeAbsolute(value, key);
    m_AbsolutePaths.insert(std::make_pair(key, value));
  }
}

/**
 * Make a relative path or a list of relative paths into an absolute one.
 * @param dir The directory to convert
 * @param key The key variable this relates to
 * @returns A string containing an aboluste path by resolving the relative directory with the executable directory
 */
std::string ConfigServiceImpl::makeAbsolute(const std::string & dir, const std::string & key) const
{
  std::string converted;
  const std::string execdir(getBaseDir());
  // If we have a list, chop it up and convert each one
  if (dir.find_first_of(";,") != std::string::npos)
  {
    int options = Poco::StringTokenizer::TOK_TRIM + Poco::StringTokenizer::TOK_IGNORE_EMPTY;
    Poco::StringTokenizer tokenizer(dir, ";,", options);
    Poco::StringTokenizer::Iterator iend = tokenizer.end();
    for (Poco::StringTokenizer::Iterator itr = tokenizer.begin(); itr != iend;)
    {
      std::string absolute = makeAbsolute(*itr, key);
      if (absolute.empty())
      {
        ++itr;
      }
      else
      {
        converted += absolute;
        if (++itr != iend)
        {
          converted += ";";
        }
      }
    }
    return converted;
  }

  // MG 05/10/09: When the Poco::FilePropertyConfiguration object reads its key/value pairs it
  // treats a backslash as the start of an escape sequence. If the next character does not
  // form a valid sequence then the backslash is removed from the stream. This has the effect
  // of giving malformed paths when using Windows-style directories. E.g C:\Mantid ->C:Mantid
  // and Poco::Path::isRelative throws an exception on this
  bool is_relative(false);
  try
  {
    is_relative = Poco::Path(dir).isRelative();
  } catch (Poco::PathSyntaxException &)
  {
    g_log.warning() << "Malformed path detected in the \"" << key << "\" variable, skipping \"" << dir
        << "\"\n";
    return "";
  }
  if (is_relative)
  {
    converted = Poco::Path(execdir).resolve(dir).toString();
  }
  else
  {
    converted = dir;
  }
  converted = Poco::Path(converted).makeDirectory().toString();

  // C++ doesn't have a const version of operator[] for maps so I can't call that here
  std::map<std::string, bool>::const_iterator it = m_ConfigPaths.find(key);
  bool required = false;
  if (it != m_ConfigPaths.end())
  {
    required = it->second;
  }
  if (required && !Poco::File(converted).exists())
  {
    g_log.warning() << "Required properties path \"" << converted << "\" in the \"" << key
        << "\" variable does not exist.\n";
    converted = "";
  }
  return converted;
}

/**
 * Create the store of data search paths from the 'datasearch.directories' key within the Mantid.properties file.
 * The value of the key should be a semi-colon separated list of directories
 */
void ConfigServiceImpl::cacheDataSearchPaths()
{
  m_DataSearchDirs.clear();
  std::string paths = getString("datasearch.directories");
  //Nothing to do
  if (paths.empty())
    return;
  int options = Poco::StringTokenizer::TOK_TRIM + Poco::StringTokenizer::TOK_IGNORE_EMPTY;
  Poco::StringTokenizer tokenizer(paths, ";,", options);
  Poco::StringTokenizer::Iterator iend = tokenizer.end();
  m_DataSearchDirs.reserve(tokenizer.count());
  for (Poco::StringTokenizer::Iterator itr = tokenizer.begin(); itr != iend; ++itr)
  {
    m_DataSearchDirs.push_back(*itr);
  }
}

/**
 * writes a basic placeholder user.properties file to disk
 * any errors are caught and logged, but not propagated
 */
void ConfigServiceImpl::createUserPropertiesFile() const
{
  try
  {
    std::fstream filestr((getOutputDir() + m_user_properties_file_name).c_str(), std::fstream::out);

    filestr << "# This file can be used to override any properties for this installation." << std::endl;
    filestr
        << "# Any properties found in this file will override any that are found in the Mantid.Properties file"
        << std::endl;
    filestr
        << "# As this file will not be replaced with futher installations of Mantid it is a safe place to put "
        << std::endl;
    filestr << "# properties that suit your particular installation." << std::endl;
    filestr << "" << std::endl;
    filestr << "#for example" << std::endl;
    filestr
        << "#uncommenting the line below will set the number of algorithms to retain interim results for to be 90"
        << std::endl;
    filestr << "#overriding any value set in the Mantid.properties file" << std::endl;
    filestr << "#algorithms.retained = 90" << std::endl;

    filestr.close();
  } catch (std::runtime_error ex)
  {
    g_log.warning() << "Unable to write out user.properties file to " << getOutputDir()
        << m_user_properties_file_name << " error: " << ex.what() << std::endl;
  }

}

/**
 * Provides a default Configuration string to use if the config file cannot be loaded.
 * @returns The string value of default properties
 */
std::string ConfigServiceImpl::defaultConfig() const
{
  std::string propFile = "# logging configuration"
    "# root level message filter (drop to debug for more messages)"
    "logging.loggers.root.level = debug"
    "# splitting the messages to many logging channels"
    "logging.loggers.root.channel.class = SplitterChannel"
    "logging.loggers.root.channel.channel1 = consoleChannel"
    "logging.loggers.root.channel.channel2 = fileFilterChannel"
    "logging.loggers.root.channel.channel3 = signalChannel"
    "# output to the console - primarily for console based apps"
    "logging.channels.consoleChannel.class = ConsoleChannel"
    "logging.channels.consoleChannel.formatter = f1"
    "# specfic filter for the file channel raising the level to warning (drop to debug for debugging)"
    "logging.channels.fileFilterChannel.class= FilterChannel"
    "logging.channels.fileFilterChannel.channel= fileChannel"
    "logging.channels.fileFilterChannel.level= warning"
    "# output to a file (For error capturing and debugging)"
    "logging.channels.fileChannel.class = debug"
    "logging.channels.fileChannel.path = ../logs/mantid.log"
    "logging.channels.fileChannel.formatter.class = PatternFormatter"
    "logging.channels.fileChannel.formatter.pattern = %Y-%m-%d %H:%M:%S,%i [%I] %p %s - %t"
    "logging.formatters.f1.class = PatternFormatter"
    "logging.formatters.f1.pattern = %s-[%p] %t"
    "logging.formatters.f1.times = UTC;"
    "# SignalChannel - Passes messages to the MantidPlot User interface"
    "logging.channels.signalChannel.class = SignalChannel";
  return propFile;
}

//-------------------------------
// Public member functions
//-------------------------------

/** Updates and existing configuration and restarts the logging
 *  @param filename The filename and optionally path of the file to load
 *  @param append   If false (default) then any previous configuration is discarded,
 *                  otherwise the new keys are added, and repeated keys will override existing ones.
 *  @param update_caches If true(default) then the various property caches are updated
 */
void ConfigServiceImpl::updateConfig(const std::string& filename, const bool append,
    const bool update_caches)
{
  loadConfig(filename, append);
  configureLogging();
  if (update_caches)
  {
    //Ensure that any relative paths given in the configuration file are relative to the correct directory
    convertRelativeToAbsolute();
    //Configure search paths into a specially saved store as they will be used frequently
    cacheDataSearchPaths();
  }
}

/**
 * Save the configuration to the user file
 * @param filename The filename for the saved configuration
 * @throws std::runtime_error if the file cannot be opened
 */
void ConfigServiceImpl::saveConfig(const std::string & filename) const
{
  if (m_changed_keys.empty())
    return;

  // Open and read the user properties file
  std::string updated_file("");

  std::ifstream reader(filename.c_str(), std::ios::in);
  if (reader.bad())
  {
    g_log.error() << "Error reading current user properties file. Cannot save updated configuration.\n";
    throw std::runtime_error("Error opening user properties file. Cannot save updated configuration.");
  }

  std::string file_line(""), output("");
  bool line_continuing(false);
  while (std::getline(reader, file_line))
  {
    if (!file_line.empty())
    {
      char last = *(file_line.end() - 1);
      if (last == '\\')
      {
        line_continuing = true;
        output += file_line + "\n";
        continue;
      }
      else if (line_continuing)
      {
        output += file_line;
        line_continuing = false;
      }
      else
      {
        output = file_line;
      }
    }
    else
    {
      output = "";
      updated_file += "\n";
      continue;
    }
    std::set<std::string>::iterator iend = m_changed_keys.end();
    std::set<std::string>::iterator itr = m_changed_keys.begin();
    for (; itr != iend; ++itr)
    {
      if (output.find(*itr) != std::string::npos)
      {
        break;
      }
    }

    if (itr == iend)
    {
      updated_file += output;
    }
    else
    {
      std::string key = *itr;
      std::string value = getString(*itr, false);
      updated_file += key + "=" + value;
      //Remove the key from the changed key list
      m_changed_keys.erase(itr);
    }
    updated_file += "\n";

  }

  // Any remaining keys within the changed key store weren't present in the current user properties so append them
  if (!m_changed_keys.empty())
  {
    updated_file += "\n";
    std::set<std::string>::iterator key_end = m_changed_keys.end();
    for (std::set<std::string>::iterator key_itr = m_changed_keys.begin(); key_itr != key_end;)
    {
      updated_file += *key_itr + "=";
      updated_file += getString(*key_itr, false);
      if (++key_itr != key_end)
      {
        updated_file += "\n";
      }
    }
    m_changed_keys.clear();
  }

  // Write out the new file
  std::ofstream writer(filename.c_str(), std::ios_base::trunc);
  if (writer.bad())
  {
    writer.close();
    g_log.error() << "Error writing new user properties file. Cannot save current configuration.\n";
    throw std::runtime_error(
        "Error writing new user properties file. Cannot save current configuration.");
  }

  writer.write(updated_file.c_str(), updated_file.size());
  writer.close();
}

/** Searches for a string within the currently loaded configuaration values and
 *  returns the value as a string. If the key is one of those that was a possible relative path
 *  then the local store is searched first.
 *
 *  @param keyName The case sensitive name of the property that you need the value of.
 *  @param use_cache If true, the local cache of directory names is queried first.
 *  @returns The string value of the property, or an empty string if the key cannot be found
 */
std::string ConfigServiceImpl::getString(const std::string& keyName, bool use_cache) const
{
  if (use_cache)
  {
    std::map<std::string, std::string>::const_iterator mitr = m_AbsolutePaths.find(keyName);
    if (mitr != m_AbsolutePaths.end())
    {
      return (*mitr).second;
    }
  }
  std::string retVal;
  try
  {
    retVal = m_pConf->getString(keyName);
  } catch (Poco::NotFoundException&)
  {
    g_log.debug() << "Unable to find " << keyName << " in the properties file" << std::endl;
    retVal = "";
  }
  return retVal;
}

/**
 * Set a configuration property. An existing key will have its value updated.
 * @param key The key to refer to this property
 * @param value The value of the property
 */
void ConfigServiceImpl::setString(const std::string & key, const std::string & value)
{
  std::string old;
  try
  {
    old = m_pConf->getString(key);
  }
  catch ( Poco::NotFoundException & )
  {
    old = "";
  }
  
  //Ensure we keep a correct full path
  std::map<std::string, bool>::const_iterator itr = m_ConfigPaths.find(key);
  if (itr != m_ConfigPaths.end())
  {
    m_AbsolutePaths[key] = makeAbsolute(value, key);
  }

  if (key == "datasearch.directories")
  {
    cacheDataSearchPaths();
  }

  // If this key exists within the loaded configuration then mark that its value will have
  // changed from the default
  if (m_pConf->hasProperty(key))
  {
    m_changed_keys.insert(key);
  }

  m_pConf->setString(key, value);
  
  if (  value != old )
    m_notificationCenter.postNotification(new ValueChanged(key, value, old));
}

/** Searches for a string within the currently loaded configuaration values and
 *  attempts to convert the values to the template type supplied.
 *
 *  @param keyName The case sensitive name of the property that you need the value of.
 *  @param out     The value if found
 *  @returns A success flag - 0 on failure, 1 on success
 */
template<typename T>
int ConfigServiceImpl::getValue(const std::string& keyName, T& out)
{
  std::string strValue = getString(keyName);
  int result = StrFunc::convert(strValue, out);
  return result;
}

/**
 * Return the full filename of the user properties file
 * @returns A string containg the full path to the user file
 */
std::string ConfigServiceImpl::getUserFilename() const
{
  return getOutputDir() + m_user_properties_file_name;
}

/** Searches for the string within the environment variables and returns the
 *  value as a string.
 *
 *  @param keyName The name of the environment variable that you need the value of.
 *  @returns The string value of the property
 */
std::string ConfigServiceImpl::getEnvironment(const std::string& keyName)
{
  return m_pSysConfig->getString("system.env." + keyName);
}

/** Gets the name of the host operating system
 *
 *  @returns The name pf the OS version
 */
std::string ConfigServiceImpl::getOSName()
{
  return m_pSysConfig->getString("system.osName");
}

/** Gets the name of the computer running Mantid
 *
 *  @returns The  name of the computer
 */
std::string ConfigServiceImpl::getOSArchitecture()
{
  return m_pSysConfig->getString("system.osArchitecture");
}

/** Gets the name of the operating system Architecture
 *
 * @returns The operating system architecture
 */
std::string ConfigServiceImpl::getComputerName()
{
  return m_pSysConfig->getString("system.nodeName");
}

/** Gets the name of the operating system version
 *
 * @returns The operating system version
 */
std::string ConfigServiceImpl::getOSVersion()
{
  return m_pSysConfig->getString("system.osVersion");
}

/** Gets the absolute path of the current directory containing the dll
 *
 * @returns The absolute path of the current directory containing the dll
 */
std::string ConfigServiceImpl::getCurrentDir()
{
  return m_pSysConfig->getString("system.currentDir");
}

/** Gets the absolute path of the temp directory
 *
 * @returns The absolute path of the temp directory
 */
std::string ConfigServiceImpl::getTempDir()
{
  return m_pSysConfig->getString("system.tempDir");
}

/**
 * Gets the directory that we consider to be the bse directory. Basically, this is the
 * executable directory when running normally or the current directory on startup when
 * running through Python on the command line
 * @returns The directory to consider as the base directory, including a trailing slash
 */
std::string ConfigServiceImpl::getBaseDir() const
{
  return m_strBaseDir;
}

/**
 * Return the directory that Mantid should use for writing files. A trailing slash is appended
 * so that filenames can more easily be concatenated with this
 * @return the directory that Mantid should use for writing files
 */
std::string ConfigServiceImpl::getOutputDir() const
{
#ifdef _WIN32 
  return m_strBaseDir;
#else
  Poco::Path datadir(m_pSysConfig->getString("system.homeDir"));
  datadir.append(".mantid");
  // Create the directory if it doesn't already exist
  Poco::File(datadir).createDirectory();
  return datadir.toString() + "/";
#endif
}

/**
 * Return the list of search paths
 * @returns A vector of strings containing the defined search directories
 */
const std::vector<std::string>& ConfigServiceImpl::getDataSearchDirs() const
{
  return m_DataSearchDirs;
}

/**
 * Return the filename of the instrument geometry definition file.
 * @param instrumentName A string giving the instrument name
 * @returns A string containing the full qualified filename of the instrument file.
 */
const std::string ConfigServiceImpl::getInstrumentFilename(const std::string& instrumentName) const
{
  // Determine the search directory for XML instrument definition files (IDFs)
  std::string directoryName = getString("instrumentDefinition.directory");
  if (directoryName.empty())
  {
    // This is the assumed deployment directory for IDFs, where we need to be relative to the
    // directory of the executable, not the current working directory.
    directoryName = Poco::Path(getBaseDir()).resolve("../Instrument").toString();
  }

  // force ID to upper case
  std::string instrument;
  instrument = instrumentName;
  std::transform(instrument.begin(), instrument.end(), instrument.begin(), toupper);
  std::string fullPathIDF = directoryName + "/" + instrument + "_Definition.xml";

  return fullPathIDF;
}

/**
 * Load facility information from instrumentDir/Facilities.xml file if fName parameter
 * is not set
 * @param fName An alternative file name for loading facilities information.
 */
void ConfigServiceImpl::updateFacilities(const std::string& fName)
{
  m_facilities.clear();

  std::string instrDir = getString("instrumentDefinition.directory");
  std::string fileName = fName.empty() ? instrDir + "Facilities.xml" : fName;

  // Set up the DOM parser and parse xml file
  Poco::XML::DOMParser pParser;
  Poco::XML::Document* pDoc;
  try
  {
    pDoc = pParser.parse(fileName);
  } catch (...)
  {
    g_log.error("Unable to parse file " + fileName);
    throw Kernel::Exception::FileError("Unable to parse file:", fileName);
  }
  // Get pointer to root element
  Poco::XML::Element* pRootElem = pDoc->documentElement();
  if (!pRootElem->hasChildNodes())
  {
    g_log.error("XML file: " + fileName + "contains no root element.");
    throw std::runtime_error("No root element in Facilities.xml file");
  }

  Poco::XML::NodeList* pNL_facility = pRootElem->getElementsByTagName("facility");
  unsigned int n = pNL_facility->length();

  for (unsigned int i = 0; i < n; ++i)
  {
    Poco::XML::Element* elem = dynamic_cast<Poco::XML::Element*> (pNL_facility->item(i));
    if (elem)
    {
      m_facilities.push_back(new FacilityInfo(elem));
    }
  }

  if (m_facilities.empty())
  {
    throw std::runtime_error("The facility definition file " + fileName + " defines no facilities");
  }

  pNL_facility->release();
  pDoc->release();
}

/** Get the default facility
 */
const FacilityInfo& ConfigServiceImpl::Facility() const
{
  std::string defFacility = getString("default.facility");
  if (defFacility.empty())
  {
    defFacility = "ISIS";
  }
  return Facility(defFacility);
}

/**  Add an observer to a notification
     @param observer Reference to the observer to add
 */
void ConfigServiceImpl::addObserver(const Poco::AbstractObserver& observer)const
{
    m_notificationCenter.addObserver(observer);
}

/**  Remove an observer
     @param observer Reference to the observer to remove
 */
void ConfigServiceImpl::removeObserver(const Poco::AbstractObserver& observer)const
{
    m_notificationCenter.removeObserver(observer);
}


/**
 * Get a facility
 * @param fName Facility name
 * @throws NotFoundException if the facility is not found
 */
const FacilityInfo& ConfigServiceImpl::Facility(const std::string& fName) const
{
  std::vector<FacilityInfo*>::const_iterator it = m_facilities.begin();
  for (; it != m_facilities.end(); ++it)
  {
    if ((**it).name() == fName)
    {
      return **it;
    }
  }
  g_log.error("Facility " + fName + " not found");
  throw Exception::NotFoundError("Facilities", fName);
}

/// \cond TEMPLATE
template DLLExport int ConfigServiceImpl::getValue(const std::string&, double&);
template DLLExport int ConfigServiceImpl::getValue(const std::string&, std::string&);
template DLLExport int ConfigServiceImpl::getValue(const std::string&, int&);
/// \endcond TEMPLATE

} // namespace Kernel
} // namespace Mantid