#include "tt_llcht.h"

// ===================================================================
// Variables
// ===================================================================

uint32_t tt_num_cached;
static tt_entry_t *table[TT_LLCHT_SIZE+1];

// ===================================================================
// Helper declarations
// ===================================================================

tt_entry_t *
new_ll_node(const uint64_t key, const enum TT_FLAG flag,
						const uint8_t depth, const float value,
						const action_t action);


// ===================================================================
// Exported functions
// ===================================================================

int tt_init(void) {
	for (uint32_t k=0; k<=TT_LLCHT_SIZE; k++)
		table[k] = NULL;
	return EXIT_SUCCESS;
}

void tt_free(void) {
	tt_entry_t *n, *nn;
	for (uint32_t k=0; k<=TT_LLCHT_SIZE; k++) {
		n = table[k];
		while (n) {
			nn = n->next;
			free(n);
			n = nn;
		}
	}
}

tt_entry_t *tt_seek(const uint64_t key) {
	tt_entry_t *lookup = table[key & TT_LLCHT_SIZE];
	while (lookup && lookup->key != key)
		lookup = lookup->next;
	return lookup;
}

int tt_insert(const uint64_t key, const enum TT_FLAG flag,
							const uint8_t depth, const float value,
							const action_t action) {
	tt_entry_t *new = new_ll_node(key, flag, depth, value, action), *n;
	// TODO: trap

	const uint32_t idx = key & TT_LLCHT_SIZE;
	if ((n = table[idx]) != NULL) {
		for (; n->next != NULL; n = n->next);
		n->next = new;
	} else {
		table[idx] = new;
	}

	tt_num_cached++;

	return EXIT_SUCCESS;
}

// ===================================================================
// Helper function implementations
// ===================================================================

tt_entry_t *
new_ll_node(const uint64_t key, const enum TT_FLAG flag,
						const uint8_t depth, const float value,
						const action_t action) {
	tt_entry_t *new = malloc(sizeof(struct tt_node_s));
	// TODO: trap errno
	new->key = key;
	new->next = NULL;
	new->flag = flag;
	new->depth = depth;
	new->value = value;
	new->action = action;
	return new;
}