esmreader.hpp

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#ifndef OPENMW_ESM_READER_H
#define OPENMW_ESM_READER_H

#include <stdint.h>
#include <string.h>
#include <cassert>
#include <vector>
#include <sstream>

#include <components/files/constrainedfilestream.hpp>

#include <components/misc/stringops.hpp>

#include <components/to_utf8/to_utf8.hpp>

#include "esmcommon.hpp"
#include "loadtes3.hpp"

namespace ESM {

class ESMReader
{
public:

  ESMReader();

  /*************************************************************************
   *
   *  Information retrieval
   *
   *************************************************************************/

  int getVer() const { return mHeader.mData.version; }
  int getRecordCount() const { return mHeader.mData.records; }
  float getFVer() const { return (mHeader.mData.version == VER_12) ? 1.2f : 1.3f; }
  const std::string getAuthor() const { return mHeader.mData.author; }
  const std::string getDesc() const { return mHeader.mData.desc; }
  const std::vector<Header::MasterData> &getGameFiles() const { return mHeader.mMaster; }
  const Header& getHeader() const { return mHeader; }
  int getFormat() const;
  const NAME &retSubName() const { return mCtx.subName; }
  uint32_t getSubSize() const { return mCtx.leftSub; }
  std::string getName() const;

  /*************************************************************************
   *
   *  Opening and closing
   *
   *************************************************************************/

  ESM_Context getContext();

  void restoreContext(const ESM_Context &rc);

  void close();

  void openRaw(Files::IStreamPtr _esm, const std::string &name);

  void open(Files::IStreamPtr _esm, const std::string &name);

  void open(const std::string &file);

  void openRaw(const std::string &filename);

  size_t getFileOffset();

  // This is a quick hack for multiple esm/esp files. Each plugin introduces its own
  //  terrain palette, but ESMReader does not pass a reference to the correct plugin
  //  to the individual load() methods. This hack allows to pass this reference
  //  indirectly to the load() method.
  int mIdx;
  void setIndex(const int index) {mIdx = index; mCtx.index = index;}
  int getIndex() {return mIdx;}

  void setGlobalReaderList(std::vector<ESMReader> *list) {mGlobalReaderList = list;}
  std::vector<ESMReader> *getGlobalReaderList() {return mGlobalReaderList;}

  /*************************************************************************
   *
   *  Medium-level reading shortcuts
   *
   *************************************************************************/

  // Read data of a given type, stored in a subrecord of a given name
  template <typename X>
  void getHNT(X &x, const char* name)
  {
    getSubNameIs(name);
    getHT(x);
  }

  // Optional version of getHNT
  template <typename X>
  void getHNOT(X &x, const char* name)
  {
      if(isNextSub(name))
          getHT(x);
  }

  // Version with extra size checking, to make sure the compiler
  // doesn't mess up our struct padding.
  template <typename X>
  void getHNT(X &x, const char* name, int size)
  {
      assert(sizeof(X) == size);
      getSubNameIs(name);
      getHT(x);
  }

  template <typename X>
  void getHNOT(X &x, const char* name, int size)
  {
      assert(sizeof(X) == size);
      if(isNextSub(name))
          getHT(x);
  }

  int64_t getHNLong(const char *name);

  // Get data of a given type/size, including subrecord header
  template <typename X>
  void getHT(X &x)
  {
      getSubHeader();
      if (mCtx.leftSub != sizeof(X))
      {
          std::stringstream error;
          error << "getHT(): subrecord size mismatch (requested " << sizeof(X) << ", got " << mCtx.leftSub << ")";
          fail(error.str());
      }
      getT(x);
  }

  // Version with extra size checking, to make sure the compiler
  // doesn't mess up our struct padding.
  template <typename X>
  void getHT(X &x, int size)
  {
      assert(sizeof(X) == size);
      getHT(x);
  }

  // Read a string by the given name if it is the next record.
  std::string getHNOString(const char* name);

  // Read a string with the given sub-record name
  std::string getHNString(const char* name);

  // Read a string, including the sub-record header (but not the name)
  std::string getHString();

  // Read the given number of bytes from a subrecord
  void getHExact(void*p, int size);

  // Read the given number of bytes from a named subrecord
  void getHNExact(void*p, int size, const char* name);

  /*************************************************************************
   *
   *  Low level sub-record methods
   *
   *************************************************************************/

  // Get the next subrecord name and check if it matches the parameter
  void getSubNameIs(const char* name);

  bool isNextSub(const char* name);

  bool peekNextSub(const char* name);

  // Store the current subrecord name for the next call of getSubName()
  void cacheSubName();

  // Read subrecord name. This gets called a LOT, so I've optimized it
  // slightly.
  void getSubName();

  // This is specially optimized for LoadINFO.
  bool isEmptyOrGetName();

  // Skip current sub record, including header (but not including
  // name.)
  void skipHSub();

  // Skip sub record and check its size
  void skipHSubSize(int size);

  // Skip all subrecords until the given subrecord or no more subrecords remaining
  void skipHSubUntil(const char* name);

  /* Sub-record header. This updates leftRec beyond the current
     sub-record as well. leftSub contains size of current sub-record.
  */
  void getSubHeader();

  void getSubHeaderIs(int size);

  /*************************************************************************
   *
   *  Low level record methods
   *
   *************************************************************************/

  // Get the next record name
  NAME getRecName();

  // Skip the rest of this record. Assumes the name and header have
  // already been read
  void skipRecord();

  /* Read record header. This updatesleftFile BEYOND the data that
     follows the header, ie beyond the entire record. You should use
     leftRec to orient yourself inside the record itself.
  */
  void getRecHeader() { getRecHeader(mRecordFlags); }
  void getRecHeader(uint32_t &flags);

  bool hasMoreRecs() const { return mCtx.leftFile > 0; }
  bool hasMoreSubs() const { return mCtx.leftRec > 0; }


  /*************************************************************************
   *
   *  Lowest level data reading and misc methods
   *
   *************************************************************************/

  template <typename X>
  void getT(X &x) { getExact(&x, sizeof(X)); }

  void getExact(void*x, int size);
  void getName(NAME &name) { getT(name); }
  void getUint(uint32_t &u) { getT(u); }

  // Read the next 'size' bytes and return them as a string. Converts
  // them from native encoding to UTF8 in the process.
  std::string getString(int size);

  void skip(int bytes);

  void fail(const std::string &msg);

  void setEncoder(ToUTF8::Utf8Encoder* encoder);

  unsigned int getRecordFlags() { return mRecordFlags; }

  size_t getFileSize() const { return mFileSize; }

private:
  Files::IStreamPtr mEsm;

  ESM_Context mCtx;

  unsigned int mRecordFlags;

  // Special file signifier (see SpecialFile enum above)

  // Buffer for ESM strings
  std::vector<char> mBuffer;

  Header mHeader;

  std::vector<ESMReader> *mGlobalReaderList;
  ToUTF8::Utf8Encoder* mEncoder;

  size_t mFileSize;

};
}
#endif