#include <sys/types.h>
#include <unistd.h> 
#include <stdio.h> 
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include <sys/time.h>
#include <time.h>
#include <string.h>

#include <hiredis-vip/hircluster.h>
#include <hiredis-vip/async.h>
#include <hiredis-vip/adapters/libevent.h>
#include <cjson/cJSON.h>

#include "tango_cache_transfer.h"
#include "tango_cache_tools.h"
#include "tango_cache_redis.h"

#define PARSE_JSON_RET_ERROR -1
#define PARSE_JSON_RET_TIMEOUT  0
#define PARSE_JSON_RET_SUCC  1

#define CACHE_REDIS_CONNECT_IDLE 0
#define CACHE_REDIS_CONNECTING   1
#define CACHE_REDIS_CONNECTED    2
#define CACHE_REDIS_DISCONNECTED 3

static void redis_asyn_disconnect_cb(const struct redisAsyncContext *ac, int status)
{
	struct tango_cache_instance *instance = (struct tango_cache_instance *)redisAsyncGetConnectionData(ac);
	
	if(status == REDIS_OK)
	{
		MESA_HANDLE_RUNTIME_LOGV2(instance->runtime_log, RLOG_LV_FATAL, "Redis disconnect %s:%d success.",
			ac->c.tcp.host, ac->c.tcp.port);
	}
	else
	{
		MESA_HANDLE_RUNTIME_LOGV2(instance->runtime_log, RLOG_LV_FATAL, "Redis disconnect %s:%d failed: %s.", 
			ac->c.tcp.host, ac->c.tcp.port, ac->errstr);
	}
	instance->redis_connecting = CACHE_REDIS_DISCONNECTED;
}

static void redis_asyn_connect_cb(const struct redisAsyncContext *ac, int status)
{
	struct tango_cache_instance *instance = (struct tango_cache_instance *)redisAsyncGetConnectionData(ac);

	if(status == REDIS_OK)
	{
		MESA_HANDLE_RUNTIME_LOGV2(instance->runtime_log, RLOG_LV_FATAL, "RedisCluster connect %s:%d success.", 
			ac->c.tcp.host, ac->c.tcp.port);
		instance->redis_connecting = CACHE_REDIS_CONNECTED;
	}
	else
	{
		instance->redis_connecting = CACHE_REDIS_CONNECT_IDLE;
		MESA_HANDLE_RUNTIME_LOGV2(instance->runtime_log, RLOG_LV_FATAL, "RedisCluster connect %s:%d failed: %s.", 
			ac->c.tcp.host, ac->c.tcp.port, ac->errstr);
	}
}

int redis_asyn_connect_init(struct tango_cache_instance *instance)
{
	instance->redis_ac = redisClusterAsyncConnect(instance->param->redisaddrs, HIRCLUSTER_FLAG_ROUTE_USE_SLOTS);
	if(instance->redis_ac == NULL)
	{
		return -1;
	}
	instance->redis_connecting = CACHE_REDIS_CONNECTING;
	redisClusterLibeventAttach(instance->redis_ac, instance->evbase);
	redisClusterAsyncSetConnectionData(instance->redis_ac, instance);
	redisClusterAsyncSetConnectCallback(instance->redis_ac, redis_asyn_connect_cb);
	redisClusterAsyncSetDisconnectCallback(instance->redis_ac, redis_asyn_disconnect_cb);
	return 0;
}

static int parse_object_meta_json(struct tango_cache_ctx *ctx, const char *jcontent)
{
	cJSON *root, *ptarget;
	int ret = PARSE_JSON_RET_ERROR;
	char usertag[2048];
	size_t datalen;

	if(NULL == (root=cJSON_Parse(jcontent)))
	{
		goto out_json;
	}
	if(NULL == (ptarget=cJSON_GetObjectItem(root, "Content-Length")))
	{
		goto out_json;
	}
	ctx->get.result.tlength = ptarget->valuedouble;
	if(NULL==(ptarget=cJSON_GetObjectItem(root, "X-Amz-Meta-Lm")))
	{
		goto out_json;
	}
	ctx->get.last_modify = ptarget->valuedouble;
	if(NULL==(ptarget=cJSON_GetObjectItem(root, "Expires")))
	{
		goto out_json;
	}
	ctx->get.expires = ptarget->valuedouble;
	ctx->get.need_hdrs = RESPONSE_HDR_ALL;
	if(!check_expires_fresh_header(ctx))
	{
		ret = PARSE_JSON_RET_TIMEOUT;
		goto out_json;
	}
	
	if(NULL!=(ptarget=cJSON_GetObjectItem(root, "Headers")))
	{
		easy_string_savedata(&ctx->response, ptarget->valuestring, strlen(ptarget->valuestring));
	}
	if(NULL!=(ptarget=cJSON_GetObjectItem(root, "X-Amz-Meta-User")))
	{
		if((datalen = Base64_DecodeBlock((unsigned char*)ptarget->valuestring, strlen(ptarget->valuestring), (unsigned char*)usertag, 2048))>0)
		{
			easy_string_savedata(&ctx->get.response_tag, usertag, datalen);
		}
	}
	cJSON_Delete(root); 
	return PARSE_JSON_RET_SUCC;
	
out_json:
	cJSON_Delete(root); 
	return ret;
}

static void redis_hget_command_cb(struct redisClusterAsyncContext *ac, void *vreply, void *privdata)
{
	redisReply *reply = (redisReply *)vreply;
	struct tango_cache_ctx *ctx  = (struct tango_cache_ctx *)privdata;
	int ret;

	ctx->instance->statistic.session_redis -= 1;
	if(reply == NULL || reply->type!=REDIS_REPLY_ARRAY)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_EXEC);
		if(reply!=NULL && reply->type==REDIS_REPLY_ERROR)
		{
			promise_failed(ctx->promise, FUTURE_ERROR_CANCEL, reply->str);
		}
		else
		{
			promise_failed(ctx->promise, FUTURE_ERROR_CANCEL, tango_cache_get_errstring(ctx));
		}
		tango_cache_ctx_destroy(ctx);
		return;
	}
	else if(reply->element[0]->type == REDIS_REPLY_NIL)
	{
		tango_cache_set_fail_state(ctx, CACHE_CACHE_MISS);
		ctx->get.result.type = RESULT_TYPE_MISS;
		promise_success(ctx->promise, &ctx->get.result);
		promise_finish(ctx->promise);
		tango_cache_ctx_destroy(ctx);
		return;
	}

	switch(ctx->get.state)
	{
		case GET_STATE_REDIS_META:
			ctx->get.result.location = (strcmp(reply->element[1]->str, "redis"))?OBJECT_IN_MINIO:OBJECT_IN_REDIS;
			break;
		case GET_STATE_REDIS_ALL:
			ctx->get.result.location = OBJECT_IN_REDIS;
			break;

		case GET_STATE_REDIS_TRY:
			ctx->get.result.location = (strcmp(reply->element[1]->str, "redis"))?OBJECT_IN_MINIO:OBJECT_IN_REDIS;
			if(ctx->get.result.location == OBJECT_IN_MINIO)
			{
				ctx->get.redis_redirect_minio_cb(ctx);
				return;
			}
			ctx->locate = OBJECT_IN_REDIS;
			break;
		default: assert(0);break;
	}
	
	ret = parse_object_meta_json(ctx, reply->element[0]->str);
	switch(ret)
	{
		case PARSE_JSON_RET_ERROR:
			tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_JSON);
			promise_failed(ctx->promise, FUTURE_ERROR_CANCEL, tango_cache_get_errstring(ctx));
			tango_cache_ctx_destroy(ctx);
			break;
		case PARSE_JSON_RET_TIMEOUT:
			if(ctx->get.state == GET_STATE_DELETE && ctx->get.result.location==OBJECT_IN_MINIO)
			{
				ctx->get.state = GET_STATE_END;
				cache_delete_minio_object(ctx);
			}
			else
			{
				tango_cache_ctx_destroy(ctx);
			}
			break;
		case PARSE_JSON_RET_SUCC:
			fetch_header_over_biz(ctx);
			if(ctx->get.state != GET_STATE_REDIS_META)
			{
				ctx->get.result.data_frag = reply->element[2]->str;
				ctx->get.result.size = reply->element[2]->len;
				ctx->get.result.type = RESULT_TYPE_BODY;
				promise_success(ctx->promise, &ctx->get.result);
			}
			ctx->get.result.type = RESULT_TYPE_END;
			promise_success(ctx->promise, &ctx->get.result);
			promise_finish(ctx->promise);
			tango_cache_ctx_destroy(ctx);
			break;
		default: assert(0);break;
	}
}

int tango_cache_head_redis(struct tango_cache_ctx *ctx)
{
	int ret = -1;

	ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hget_command_cb, ctx, 
		"HMGET %s OBJECT_META OBJECT_LOCATION", ctx->object_key);
	if(ret != REDIS_OK)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_CONNECT);
		tango_cache_ctx_destroy(ctx);
	}
	else
	{
		ctx->instance->statistic.session_redis += 1;
		ctx->get.state = GET_STATE_REDIS_META;
	}
	return ret;
}

int tango_cache_fetch_redis(struct tango_cache_ctx *ctx)
{
	int ret = -1;

	ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hget_command_cb, ctx,
		"HMGET %s OBJECT_META OBJECT_LOCATION OBJECT_BODY", ctx->object_key);
	if(ret != REDIS_OK)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_CONNECT);
		tango_cache_ctx_destroy(ctx);
	}
	else
	{
		ctx->instance->statistic.session_redis += 1;
		ctx->get.state = GET_STATE_REDIS_ALL;
	}
	return ret;
}

int tango_cache_try_fetch_redis(struct tango_cache_ctx *ctx)
{
	int ret = -1;

	ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hget_command_cb, ctx,
		"HMGET %s OBJECT_META OBJECT_LOCATION OBJECT_BODY", ctx->object_key);
	if(ret != REDIS_OK)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_CONNECT);
		tango_cache_ctx_destroy(ctx);
	}
	else
	{
		ctx->instance->statistic.session_redis += 1;
		ctx->get.state = GET_STATE_REDIS_TRY;
	}
	return ret;
}

static void redis_hset_command_cb(struct redisClusterAsyncContext *ac, void *vreply, void *privdata)
{
	struct tango_cache_ctx *ctx = (struct tango_cache_ctx *)privdata;
	redisReply *reply = (redisReply *)vreply;
	int ret;

	ctx->instance->statistic.session_redis -= 1;
	if(reply == NULL || reply->type==REDIS_REPLY_ERROR || ac->err)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_EXEC);
	}
	if(ctx->fail_state)
	{
		tango_cache_ctx_destroy(ctx, true);
		return;
	}

	switch(ctx->put.state)
	{
		case PUT_STATE_REDIS_META:
		case PUT_STATE_REDIS_ALL:
			ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hset_command_cb, ctx, 
				"EXPIRE %s %u", ctx->object_key, ctx->put.object_ttl);
			if(ret != REDIS_OK)
			{
				tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_EXEC);
				tango_cache_ctx_destroy(ctx, true);
			}
			else
			{
				ctx->instance->statistic.session_redis += 1;
				ctx->put.state = PUT_STATE_END;
			}
			break;
		case PUT_STATE_END:
			tango_cache_ctx_destroy(ctx, true);
			break;
		default: assert(0);break;
	}
}

int redis_put_minio_object_meta(struct tango_cache_ctx *ctx, bool callback)
{
	int ret;
	char *meta;

	meta = cJSON_PrintUnformatted(ctx->put.object_meta);
	ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hset_command_cb, ctx,
		"HMSET %s OBJECT_LOCATION minio OBJECT_META %s", ctx->object_key, meta);
	if(ret != REDIS_OK)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_CONNECT);
		tango_cache_ctx_destroy(ctx, callback);
	}
	else
	{
		ctx->instance->statistic.session_redis += 1;
		ctx->put.state = PUT_STATE_REDIS_META;
	}
	free(meta);
	return ret;
}

int redis_put_complete_part_data(struct tango_cache_ctx *ctx, enum PUT_MEMORY_COPY_WAY way, const char *data, size_t size, bool callback)
{
	int ret;
	char *meta;

	ctx->instance->statistic.memory_used -= size;
	meta = cJSON_PrintUnformatted(ctx->put.object_meta);
	ret = redisClusterAsyncCommand(ctx->instance->redis_ac, redis_hset_command_cb, ctx, 
		"HMSET %s OBJECT_LOCATION redis OBJECT_META %s OBJECT_BODY %b", ctx->object_key, meta, data, size);
	if(ret != REDIS_OK)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_REDIS_CONNECT);
		tango_cache_ctx_destroy(ctx, callback);
	}
	else
	{
		ctx->instance->statistic.session_redis += 1;
		ctx->put.state = PUT_STATE_REDIS_ALL;
	}
	if(way == PUT_MEM_FREE) 
	{
		free((void *)data);
	}
	free(meta);
	return ret;
}

int redis_put_complete_part_evbuf(struct tango_cache_ctx *ctx, size_t object_size, bool callback)
{
	char *data;
	size_t size;

	data = (char *)malloc(object_size);	
	size = evbuffer_remove(ctx->put.evbuf, data, object_size);
	if(size != object_size)
	{
		tango_cache_set_fail_state(ctx, CACHE_ERR_EVBUFFER);
		tango_cache_ctx_destroy(ctx, callback);
		free(data);
		return CACHE_ERR_EVBUFFER;
	}
	return redis_put_complete_part_data(ctx, PUT_MEM_FREE, data, object_size, callback);
}