#include "key_keeper.h"
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "MESA/MESA_prof_load.h"
#include "tfe_rpc.h"
#include "event2/http.h"
#define HTABLE_MAX_KEY_LEN 256
#define KEYRING_EXSITED 0
#define KEYRING_NOT_EXSITED -1

struct key_keeper
{
    unsigned int mode;
	char cert_store_host[TFE_STRING_MAX];
	unsigned int cert_store_port;
    MESA_htable_handle htable;
    void* logger;
};

enum KEY_KEEPER_MODE{
	NORMAL = 0,
	DEBUG,
};

struct keyring_private
{
	struct keyring head;
	pthread_mutex_t mutex;
	size_t references;
};

struct key_keeper_promise_ctx
{
	void* logger;
	MESA_htable_handle htable;
	const uchar* key;
	unsigned int key_len;
};

static const uchar* get_key_by_cert(X509* cert, int keyring_id, unsigned int* len);

static struct keyring_private* keyring_new(void)
{
	struct keyring_private *kyr;
	if (!(kyr = (struct keyring_private *)ALLOC(struct keyring_private, 1)))
	{
		return NULL;
	}
	if (pthread_mutex_init(&kyr->mutex, NULL)) {
		free(kyr);
		return NULL;
	}
	kyr->references = 1;
	return kyr;
}

/*
 * Passed OpenSSL objects are owned by cert_t; refcount will not be
 * incremented, stack will not be duplicated.
 */
struct keyring* keyring_new3(EVP_PKEY *key, X509 *cert, STACK_OF(X509) *chain)
{
	struct keyring_private* kyr=NULL;
	kyr=keyring_new();

	kyr->references = 1;
	(kyr->head).key = key;
	(kyr->head).cert = cert;
	(kyr->head).chain = chain;
	if(key)
	{
		ssl_key_refcount_inc(key);
	}
	if(cert)
	{
		ssl_x509_refcount_inc(cert);
	}
	if(chain){
        int i = 0;
		for (i = 0; i < sk_X509_num(chain); i++)
		{
			ssl_x509_refcount_inc(sk_X509_value(chain, i));
		}
	}
	return &(kyr->head);
}

// Increment reference count.
void keyring_ref_inc(struct keyring_private* kyr)
{
	pthread_mutex_lock(&kyr->mutex);
	kyr->references++;
	pthread_mutex_unlock(&kyr->mutex);
}

/*
 * Thread-safe setter functions; they copy the value (refcounts are inc'd).
 */
static void keyring_set_key(struct keyring_private* kyr, EVP_PKEY *key)
{
	pthread_mutex_lock(&kyr->mutex);
	if ((kyr->head).key)
	{
		EVP_PKEY_free((kyr->head).key);
	}
	(kyr->head).key = key;
	if (key)
	{
		ssl_key_refcount_inc((kyr->head).key);
	}
	pthread_mutex_unlock(&kyr->mutex);
}

static void keyring_set_cert(struct keyring_private* kry, X509 *cert)
{
	pthread_mutex_lock(&kry->mutex);
	if ((kry->head).cert)
	{
		X509_free((kry->head).cert);
	}
	(kry->head).cert = cert;
	if (cert)
	{
		ssl_x509_refcount_inc((kry->head).cert);
	}
	pthread_mutex_unlock(&kry->mutex);
}

static void keyring_set_chain(struct keyring_private* kyr, STACK_OF(X509) *chain)
{
	pthread_mutex_lock(&kyr->mutex);
	if ((kyr->head).chain)
	{
		sk_X509_pop_free((kyr->head).chain, X509_free);
	}
	if (chain)
	{
		(kyr->head).chain = sk_X509_dup(chain);
		int i = 0;
        for (i = 0; i < sk_X509_num((kyr->head).chain); i++)
		{
			ssl_x509_refcount_inc(sk_X509_value((kyr->head).chain, i));
		}
	} else
	{
		(kyr->head).chain = NULL;
	}
	pthread_mutex_unlock(&kyr->mutex);
}

/*
 * Free keyring including internal objects.
 */
void key_keeper_free_keyring(struct keyring *kyr)
{
	struct keyring_private* _kyr = (struct keyring_private*)kyr;
	pthread_mutex_lock(&_kyr->mutex);
	_kyr->references--;
	if (_kyr->references>0)
	{
		pthread_mutex_unlock(&_kyr->mutex);
		return;
	}
	pthread_mutex_unlock(&_kyr->mutex);
	pthread_mutex_destroy(&_kyr->mutex);
	if ((_kyr->head).key)
	{
		EVP_PKEY_free((_kyr->head).key);
		(_kyr->head).key=NULL;
	}
	if ((_kyr->head).cert)
	{
		X509_free((_kyr->head).cert);
		(_kyr->head).cert=NULL;
	}
	if ((_kyr->head).chain)
	{
		sk_X509_pop_free((_kyr->head).chain, X509_free);
		(_kyr->head).chain=NULL;
	}
	free(_kyr);
}

static long keyring_local_cache_query_cb(void * data, const uchar * key, uint size, void * user_arg)
{
	//data is (struct keyring*)
	struct keyring_private* kyr=(struct keyring_private*)data;
	if(kyr == NULL)
	{
		return KEYRING_NOT_EXSITED;
	}
	else
	{
		struct promise* p = (struct promise*)user_arg;
		promise_success(p, data);
		return KEYRING_EXSITED;
	}
}
static void certstore_rpc_on_fail(enum e_future_error err, const char * what, void * user)
{
	struct promise * p = (struct promise *) user;
	promise_failed(p, err, what);
}
static struct keyring_private* generate_x509_keyring(X509* origin_cert, int keyring_id, const char* filename)
{
	X509* ca = ssl_x509_load(filename);
	EVP_PKEY* cakey = ssl_key_load(filename);
	EVP_PKEY* forge_key = ssl_key_genrsa(1024);
	X509* forge_cert = ssl_x509_forge(ca, cakey, origin_cert, forge_key, NULL, NULL);
	STACK_OF(X509)* chain = sk_X509_new_null();
	sk_X509_push(chain, ca);
	sk_X509_push(chain, forge_cert);
	struct keyring_private* ring= keyring_new();
	keyring_set_key(ring, forge_key);
	keyring_set_cert(ring, forge_cert);
	keyring_set_chain(ring, chain);
	return ring;
}
//how to free
static X509* get_cert_from_response(const char* data, int len, void* logger)
{
	BIO *bio;
	X509 *cert;
	bio = BIO_new(BIO_s_mem());
	BIO_write(bio, (const void*)data, len);
	cert = PEM_read_bio_X509(bio, NULL, NULL, NULL);
	return cert;
}

static EVP_PKEY* get_key_from_response(const char* data, int len, void* logger)
{

}


static STACK_OF(X509)* get_chain_from_response(const char* data, int len, void* logger)
{

}

static void certstore_rpc_on_succ(void* result, void* user)
{
	struct promise * p = (struct promise *) user;
	struct key_keeper_promise_ctx* ctx = (struct key_keeper_promise_ctx*)promise_get_ctx(p);
	void* logger = ctx->logger;
	MESA_htable_handle htable= ctx->htable;
	const uchar* key = ctx->key;
	unsigned int key_len = ctx->key_len;
	//transform to x509
	struct tfe_rpc_response_result* response = tfe_rpc_release(result);
	int status_code = response->status_code;
	const char* status_msg = response->status_msg;
	const char* data = response->data;
	int len = response->len;
	if(status_code == HTTP_OK)
	{
		struct keyring_private* ring= keyring_new();
		X509* forge_cert = get_cert_from_response(data, len, NULL);
		EVP_PKEY* forge_key = get_key_from_response(data, len, NULL);
		STACK_OF(X509)* chain = get_chain_from_response(data, len, NULL);
		keyring_set_key(ring, forge_key);
		keyring_set_cert(ring, forge_cert);
		keyring_set_chain(ring, chain);
		promise_success(p, (void*)ring);

		keyring_ref_inc(ring);
		int ret = MESA_htable_add(htable, key, key_len, (void*)ring);
		if(ret<0)
		{
			key_keeper_free_keyring((struct keyring*)ring);
		}
	}
	else
	{
		promise_failed(p, FUTURE_ERROR_EXCEPTION, status_msg);
	}
}


static int __wrapper_MESA_htable_set_opt(MESA_htable_handle table, enum MESA_htable_opt opt_type, unsigned int value);

static MESA_htable_handle create_hash_table(unsigned int slot_size, unsigned int expire_seconds);

static STACK_OF(X509)* get_chain_from_response(const char* data, int len, void* logger);
/*
 * Certificate, including private key and keyring chain.
 */




static void key_keeper_free_serialized()
{
	return;
}

static void key_keeper_verify_cb()
{
	return;
}

struct key_keeper *
key_keeper_init(const char * profile, const char* section, void* logger)
{
	//load conf
	//TODO free
	struct key_keeper* keeper = ALLOC(struct key_keeper, 1);
	keeper->logger = logger;
    MESA_load_profile_uint_def(profile, section, "mode", &(keeper->mode), 1);
	MESA_load_profile_string_def(profile, section, "cert_store_host", keeper->cert_store_host, sizeof(keeper->cert_store_host), "xxxxx");
	MESA_load_profile_uint_def(profile, section, "cert_store_port", &(keeper->cert_store_port), 80);
	//TODO: argument
	keeper->htable = create_hash_table(16,16);
	return keeper;
}

void key_keeper_destroy(struct key_keeper *keeper)
{
	free(keeper);
	keeper = NULL;
	return;
}

struct keyring* key_keeper_release_keyring(future_result_t* result)
{
	struct keyring_private* kyr=(struct keyring_private*)result;
	keyring_ref_inc(kyr);
	return &(kyr->head);
}





static void ctx_destory_cb(struct promise* p)
{

}

//TODO: cert_not_valid
void key_keeper_async_ask(struct future * f, struct key_keeper * keeper, const char* sni, int keyring_id, X509 * origin_cert, int is_cert_valid, struct event_base * evbase)
{
	//get subject name from cert

	//current promise, belong to key_keeper
	struct promise* p = future_to_promise(f);
	struct key_keeper_promise_ctx* ctx = ALLOC(struct key_keeper_promise_ctx, 1);
	unsigned int len = 0;
	const uchar* key = get_key_by_cert(origin_cert, keyring_id, &len);
	ctx->logger = keeper->logger;
	ctx->htable = keeper->htable;
	ctx->key = key;
	ctx->key_len = len;
	promise_set_ctx(p, (void*)ctx, ctx_destory_cb);
	long int cb_rtn = 0;
	MESA_htable_search_cb(ctx->htable, (const unsigned char*)(ctx->key), ctx->key_len, keyring_local_cache_query_cb, p, &cb_rtn);
	printf(cb_rtn == KEYRING_EXSITED ? "KEYRING_EXSITED\n": "KEYRING_NOT_EXSITED\n");
	if(cb_rtn == KEYRING_EXSITED)
	{
		return;
	}
	int mode = keeper->mode;
	printf("mode is %s", mode == NORMAL ? "normal\n":"debug\n");
	switch(mode){
		case NORMAL:
        {
    		struct future* f_tfe_rpc = future_create("tfe_rpc", certstore_rpc_on_succ, certstore_rpc_on_fail, p);
    		//TODO: init in main()? store in ctx
    		struct tfe_rpc* rpc = tfe_rpc_init(NULL, NULL, keeper->logger);
			char url[TFE_STRING_MAX];
    		const char host[] = "www.baidu.com";
			snprintf(url, TFE_STRING_MAX, "%s:%d?host=%s&flag=1&valid=1&kering_id=%d", keeper->cert_store_host, keeper->cert_store_port, host, keyring_id);
    		tfe_rpc_async_ask(f_tfe_rpc, rpc, url, GET, DONE_CB, NULL, 0, evbase);
			break;
        }
		case DEBUG:
        {
			//TOOD: generate X509 cert
			const char* filename = "./conf/mesalab-ca.pem";
			struct keyring_private* ring = generate_x509_keyring(origin_cert, keyring_id, filename);
			if(ring)
			{
				keyring_ref_inc(ring);
				int ret = MESA_htable_add(ctx->htable, ctx->key, ctx->key_len, (void*)ring);
				if(ret<0)
				{
					key_keeper_free_keyring((struct keyring*)ring);
				}
				else
				{
					printf("key %s is added to hash table\n", ctx->key);
				}
				promise_success(p, (void*)ring);
				key_keeper_free_keyring((struct keyring*)ring);
			}
			else
			{
				promise_failed(p, FUTURE_ERROR_EXCEPTION, "generate X509 cert failed");
			}
			break;
        }
	}
	return;
}


static const uchar*
get_key_by_cert(X509* cert, int keyring_id, unsigned int* len)
{
	char* cert_fgr = NULL;
	cert_fgr = ssl_x509_fingerprint(cert, 0);
	char* key = (char*)malloc(HTABLE_MAX_KEY_LEN);
	*key = '\0';
	if(cert == NULL)
	{
		return NULL;
	}
	snprintf(key, HTABLE_MAX_KEY_LEN, "%d:", keyring_id);
	strncat(key, cert_fgr, HTABLE_MAX_KEY_LEN);
	*len = strnlen(key, HTABLE_MAX_KEY_LEN);
	return (const uchar*)key;
}


static int __wrapper_MESA_htable_set_opt(MESA_htable_handle table, enum MESA_htable_opt opt_type, unsigned int value)
{
    int ret = MESA_htable_set_opt(table, opt_type, &value, (int)(sizeof(value)));
    assert(ret == 0);
    return ret;
}

static MESA_htable_handle
create_hash_table(unsigned int slot_size, unsigned int expire_seconds)
{
	int ret = 0;
	unsigned max_num = slot_size * 4;
	MESA_htable_handle htable = MESA_htable_born();
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_SCREEN_PRINT_CTRL, 0);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_THREAD_SAFE, 1);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_MUTEX_NUM, 16);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_HASH_SLOT_SIZE, slot_size);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_HASH_MAX_ELEMENT_NUM, max_num);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_EXPIRE_TIME, expire_seconds);
	ret = __wrapper_MESA_htable_set_opt(htable, MHO_ELIMIMINATE_TYPE,
		HASH_ELIMINATE_ALGO_FIFO);
    //TODO: how to do overide?
	//ret = __wrapper_MESA_htable_set_opt(htable, MHO_CBFUN_DATA_FREE,
	//	(void *)key_keeper_free_serialized);
	//ret = __wrapper_MESA_htable_set_opt(htable, MHO_CBFUN_DATA_EXPIRE_NOTIFY,
	//	(void *)key_keeper_verify_cb);
	ret = MESA_htable_mature(htable);
	assert(ret == 0);
	return htable;
}