#ifndef __TTC_KEY_CODEC_H
#define __TTC_KEY_CODEC_H

#include <string.h>
#include <stdint.h>
#include "namespace.h"

TTC_BEGIN_NAMESPACE

class CKeyCodec
{
	public:
		CKeyCodec(const unsigned t)
		{
			set_key_type(t);
		}

		~CKeyCodec(){}

		void set_key_type(const unsigned t)
		{
			type = t;
		}
		unsigned key_length(const char *ptr)
		{
			return type > 0 ? type : *(unsigned char *)ptr;
		}
		unsigned total_length(const char *ptr)
		{
			return type > 0 ? key_length(ptr) : key_length(ptr)+1;
		}
		const char* key_pointer(const char *ptr)
		{
			//return  type > 0 ? ptr : ptr+1;
			return ptr;
		}
		int key_compare(const char *a, const char *b, size_t len)
		{
			switch(type)
			{
				case 1:
					return *(uint8_t *)a - *(uint8_t *)b;
				case 2:
					return *(uint16_t *)a - *(uint16_t *)b;
				case 4:
					return *(uint32_t *)a - *(uint32_t *)b;
			}

			return memcmp(a, b, len); 
		}

		unsigned key_hash(const char *ptr, size_t len)
		{
			unsigned hash = 0x123;
			//unsigned len  = total_length(ptr);

			do {
				unsigned char c = *ptr++;
				//c = icase_hash(c);
				hash = hash*101 + c;
			} while (--len);

			return hash;
		}
	private:
		/*
		 * This removes bit 5 if bit 6 is set.  (from git name-hash.c)
		 *
		 * That will make US-ASCII characters hash to their upper-case
		 * equivalent. We could easily do this one whole word at a time,
		 * but that's for future worries.
		 */
		static inline unsigned char icase_hash(unsigned char c)
		{
			return c & ~((c & 0x40) >> 1);
		}

	private:
		unsigned type;
};

TTC_END_NAMESPACE
#endif