#ifndef __RECFILE_HPP
#define __RECFILE_HPP

class File;
typedef unsigned long RecordID;
struct RecordFile_FileHeader;
struct RecordFile_ClusterBitmap;

class RecordFile {
public:
	RecordFile();
	virtual ~RecordFile();

	int open(File *fp);
	int create(File *fp, unsigned long customSize, unsigned long recordSize);
	int createtrunc(File *fp, unsigned long customSize, unsigned long recordSize);

	unsigned long getRecordSize() const;

	//custom header i/o
	unsigned long getCustomHeaderSize() const;
	int readCustomHeader(void *buf) const;
	int writeCustomHeader(const void *buf);

	//record i/o
	RecordID addRecord(const void *buf, RecordID around=0);
	int getRecord(RecordID rid, void *buf) const;
	int updateRecord(RecordID rid, const void *buf);
	RecordID removeRecord(RecordID rid);

	RecordID firstRecord();
	RecordID nextRecord(RecordID rid);
private:
	RecordID findNextUsedRecord(RecordID rid);
	void rid2cnorno(RecordID rid, unsigned long &cno, unsigned long &rno);
	void cnorno2rid(unsigned long cno, unsigned long rno, RecordID& rid);

	File *file;
	unsigned long recordSize;
	unsigned long firstClusterOffset;
	unsigned long clusterBytes;

	typedef RecordFile_FileHeader FileHeader;
	typedef RecordFile_ClusterBitmap ClusterBitmap;
	static int validateHeader(const FileHeader &h);
	int readHeader(FileHeader &h) const;
	int writeHeader(const FileHeader &h);

	int validateRecordID(RecordID rid) const;


	RecordID findFreeRecord(RecordID around);

	int readClusterBitmap(unsigned long cno, ClusterBitmap& cluster);
	int writeClusterBitmap(unsigned long cno, const ClusterBitmap& cluster);
	int createNewCluster();
	void markRecord(RecordID rid, int bit);

};

#endif