#ifndef __6D_HASHTABLE_H
#define __6D_HASHTABLE_H
/*
6D programming language
Copyright (C) 2011  Danny Milosavljevic
This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdlib.h>
#include <math.h>
#ifndef WIN32
#include <stdint.h>
#else
typedef unsigned int uint32_t; /* FIXME */
static double log2(double n) {
	// log(n)/log(2) is log2.  
	return log(n)/log(2.0);  
}
#endif
#include "Values/Values"
#include "6D/Values"
#include <math.h>
#include <string.h>

BEGIN_NAMESPACE_6D(Values)

static INLINE uint32_t jenkinsOneAtATimeHash(const char* key, size_t len) {
	uint32_t hash, i;
	for(hash = i = 0; i < len; ++i) {
		hash += key[i];
		hash += (hash << 10);
		hash ^= (hash >> 6);
	}
	hash += (hash << 3);
	hash ^= (hash >> 11);
	hash += (hash << 15);
	return hash;
}
static INLINE uint32_t jenkinsOneAtATimeHashC(const char* key) {
	uint32_t hash, i;
	for(hash = i = 0; key[i]; ++i) {
		hash += key[i];
		hash += (hash << 10);
		hash ^= (hash >> 6);
	}
	hash += (hash << 3);
	hash ^= (hash >> 11);
	hash += (hash << 15);
	return hash;
}
static INLINE uint32_t hashSymbol(NodeT sym) {
	const char* str = symbolName(sym);
	return jenkinsOneAtATimeHashC(str);
}
static INLINE bool eqSymbol(NodeT a, NodeT b) {
	return a == b;
}
static INLINE bool ltSymbol(NodeT a, NodeT b) {
	return a < b;
}
enum HashtableEntryState {
	HS_FREE,
	HS_OCCUPIED,
	HS_FREE_AGAIN,
};
struct HashtableEntry {
	enum HashtableEntryState state;
	NODET first; // key. Idiotic name because of interface compability.
	NODET second; // value. Idiotic name because of interface compability.
};
BEGIN_STRUCT_6D(Hashtable)
	int count;
	int capacity;
	bool bGC;
	struct HashtableEntry* entries; 
END_STRUCT_6D(Hashtable)
NodeT getHashtableValueByKey(NodeT hashtable, NodeT key, NodeT fallback);
void setHashtableEntry(NodeT hashtable, NodeT key, NodeT value);
void removeHashtableEntry(NodeT hashtable, NodeT key);
NodeT makeHashtable(void);
NodeT makeHashtableNoGC(void);

END_NAMESPACE_6D(Values)
#endif /* ndef __6D_HASH_TABLE_H */