#include "precompile.h"
#include <errno.h>

#include "shm_table.h"
#include "shm_mem.h"
#include "memutil.h"
#include "list.h"
#include "hash.h"
#include <winpr/synch.h>

#define HTABLE_SLOT_NUM	1023

typedef struct shm_table_entry_t
{
	struct hlist_node entry;
	char *key;
	void *data;
	int len;
}shm_table_entry_t;

typedef struct shm_table_core
{
	struct hlist_head hlist[HTABLE_SLOT_NUM];
	int cnt;
}shm_table_core;

struct shm_table_t
{
	shm_table_core *core;
	HANDLE hMutex;
	int first;
};

static HANDLE create_mutex(int shmkey)
{
	char name[32];
	sprintf(name, "shm_table%08d", shmkey);
	return CreateMutexA(NULL, FALSE, name);
}

static shm_table_entry_t *find_entry(struct hlist_head *phead, const char *key)
{
	shm_table_entry_t *tpos;
	struct hlist_node *pos;

	hlist_for_each_entry(tpos, pos, phead, shm_table_entry_t, entry) {
		if (strcmp(key, tpos->key) == 0)
			return tpos;
	}

	return NULL;
}

TOOLKIT_API int shm_table_create(shm_table_t **p_table)
{
	int i;
	shm_table_t *table;
	shm_table_core *core;

	if (!p_table)
		return -1;

	table = (shm_table_t*)malloc(sizeof(shm_table_t));
	memset(table, 0, sizeof(shm_table_t));
	table->first = TRUE;

	core = shm_malloc(sizeof(shm_table_core));
	memset(core, 0, sizeof(shm_table_core));
	for (i = 0; i < HTABLE_SLOT_NUM; ++i)
		INIT_HLIST_HEAD(&core->hlist[i]);
	table->core = core;
	table->hMutex = create_mutex((int)core);
	if (!table->hMutex) {
		shm_table_destroy(table);
		return -1;
	}

	*p_table = table;

	return 0;
}

TOOLKIT_API int shm_table_open(void *core, shm_table_t **p_table)
{
	shm_table_t *table;

	if (!p_table || !core)
		return -1;

	table = (shm_table_t*)malloc(sizeof(shm_table_t));
	memset(table, 0, sizeof(shm_table_t));
	table->first = FALSE;
	table->core = core;
	table->hMutex = create_mutex((int)core);
	if (!table->hMutex) {
		shm_table_destroy(table);
		return -1;
	}

	*p_table = table;

	return 0;
}

TOOLKIT_API void *shm_table_get_core_mem(shm_table_t *table)
{
	return table->core;
}

TOOLKIT_API int shm_table_lock(shm_table_t *table, int timeout)
{
	DWORD dwRet;
	dwRet = WaitForSingleObject(table->hMutex, (DWORD)timeout);
	return dwRet == WAIT_OBJECT_0 ? 0 : -1;
}

TOOLKIT_API int shm_table_unlock(shm_table_t *table)
{
	return ReleaseMutex(table->hMutex) ? 0 : -1;
}

TOOLKIT_API int shm_table_destroy(shm_table_t *table)
{
	if (table) {
		if (table->hMutex)
			CloseHandle(table->hMutex);
		if (table->first) {
			shm_free(table->core);
		}
		free(table);
		return 0;
	}
	return -1;
}

TOOLKIT_API int shm_table_set(shm_table_t *table, const char *key, const char *buf, int n)
{
	int idx;
	shm_table_entry_t *e;
	shm_table_core *core;

	if (!table)
		return -1;
	if (n == -1 && buf)
		n = strlen(buf) + 1;

	core = table->core;

	idx = hash32_str(key, HASH32_STR_INIT) % HTABLE_SLOT_NUM;

	e = find_entry(&core->hlist[idx], key);
	if (e) { // update
		if (!buf) { // delete 
			shm_free(e->key);
			shm_free(e->data);
			hlist_del(&e->entry);
			shm_free(e);
		} else {
			char *new_data = shm_malloc(n);
			if (!new_data)
				return -1;
			memcpy(new_data, buf, n);
			shm_free(e->data);
			e->data = new_data;
			e->len = n;
		}
	} else { // insert new 
		if (!buf)
			return -1;
		e = (shm_table_entry_t*)shm_malloc(sizeof(shm_table_entry_t));
		if (!e)
			return -1;
		e->key = shm_strdup(key);
		if (!e->key) {
			shm_free(e);
			return -1;
		}
		e->data = shm_malloc(n);
		if (!e->data) {
			shm_free(e->key);
			shm_free(e);
			return -1;
		}
		memcpy(e->data, buf, n);
		e->len = n;
		hlist_add_head(&e->entry, &core->hlist[idx]);
	}

	return 0;
}

TOOLKIT_API int shm_table_get(shm_table_t *table, const char *key, char *buf, int *n)
{
	int idx;
	shm_table_entry_t *e;
	shm_table_core *core;

	if (!table)
		return -1;

	core = table->core;

	idx = hash32_str(key, HASH32_STR_INIT) % HTABLE_SLOT_NUM;
	e = find_entry(&core->hlist[idx], key);

	if (!e)
		return -1;

	if (buf) {
		if (n) {
			if (*n < e->len) {
				*n = e->len;
				return -1;
			}
		}
		memcpy(buf, e->data, e->len);
	} else {
		if (n) {
			*n = e->len;
		} else {
			return -1;
		}
	}

	return 0;
}

TOOLKIT_API int shm_table_set_int(shm_table_t *table, const char *key, int val)
{
	return shm_table_set(table, key, (char*)&val, sizeof(int));
}

TOOLKIT_API int shm_table_get_int(shm_table_t *table, const char *key, int* val)
{
	if (!table || !val)
		return -1;
	return shm_table_get(table, key, (char*)val, NULL);
}

TOOLKIT_API int shm_table_incr_int(shm_table_t *table, const char *key, int *newvalue)
{
	int idx;
	shm_table_entry_t *e;
	shm_table_core *core;

	if (!table)
		return -1;

	core = table->core;

	idx = hash32_str(key, HASH32_STR_INIT) % HTABLE_SLOT_NUM;
	e = find_entry(&core->hlist[idx], key);

	if (!e)
		return -1;

	if (e->len != sizeof(int))
		return -1;

	*(int*)e->data = *(int*)e->data + 1;

	if (newvalue)
		*newvalue = *(int*)e->data;

	return 0;
}

TOOLKIT_API int shm_table_decr_int(shm_table_t *table, const char *key, int *newvalue)
{
	int idx;
	shm_table_entry_t *e;
	shm_table_core *core;

	if (!table)
		return -1;

	core = table->core;

	idx = hash32_str(key, HASH32_STR_INIT) % HTABLE_SLOT_NUM;

	e = find_entry(&core->hlist[idx], key);

	if (!e)
		return -1;

	if (e->len != sizeof(int))
		return -1;

	*(int*)e->data = *(int*)e->data - 1;

	if (newvalue)
		*newvalue = *(int*)e->data;

	return 0;
}