#include <cstdlib>
#include <physfs.h>
#include <sstream>
#include "m_exceptions.h"
#include "file_helper.h"

#ifndef OGTA_DEFAULT_DATA_PATH
#define OGTA_DEFAULT_DATA_PATH "gtadata.zip"
#endif
#ifndef OGTA_DEFAULT_MOD_PATH
#define OGTA_DEFAULT_MOD_PATH ""
#endif
#ifndef OGTA_DEFAULT_HOME_PATH
#ifdef LINUX
#define OGTA_DEFAULT_HOME_PATH PHYSFS_getUserDir()
#elif WIN32
#define OGTA_DEFAULT_HOME_PATH "config" 
#endif
#endif

namespace Util {
  FileHelper::FileHelper() :
    baseDataPath(OGTA_DEFAULT_DATA_PATH),
    modDataPath(OGTA_DEFAULT_MOD_PATH),
    userHomeDir(OGTA_DEFAULT_HOME_PATH) {
    const char *e = getenv("OGTA_DATA");
    if (e != NULL)
      baseDataPath = std::string(e);
    e = getenv("OGTA_MOD");
    if (e != NULL)
      modDataPath = std::string(e);
    e = getenv("OGTA_HOME");
    if (e != NULL)
      userHomeDir = std::string(e);
  }

  const std::string & FileHelper::getBaseDataPath() const {
    return baseDataPath;
  }

  const std::string & FileHelper::getModDataPath() const {
    return modDataPath;
  }

  const std::string & FileHelper::getUserHomeDir() const {
    return userHomeDir;
  }

  bool FileHelper::existsInSystemFS(const std::string & file) const {
    if (file.length() == 0)
      return 0;
#ifdef LINUX
    return (access(file.c_str(), R_OK) == 0);
#endif
#ifdef WIN32
    FILE * f = fopen(file.c_str(), "rb");
    bool res = (f != NULL);
    if (f)
      fclose(f);
    return res;
#endif
  }

  bool FileHelper::existsInVFS(const std::string & file) const {
    if (file.length() == 0)
      return 0;
    return PHYSFS_exists(file.c_str());
  }

  PHYSFS_file *FileHelper::openReadVFS(const std::string & file) const {
    PHYSFS_file * fd = PHYSFS_openRead(file.c_str());
    if (fd)
      return fd;
    // try lower case
    std::string name2(file);
    transform(name2.begin(), name2.end(), name2.begin(), tolower);
    fd = PHYSFS_openRead(name2.c_str());
    if (!fd) { // still no joy, give up
      std::ostringstream o;
      o << file << " with error: " << PHYSFS_getLastError();
      throw E_FILENOTFOUND(o.str());
    }
    // take this one instead
    return fd;
  }
}