package session

import (
	"context"
	"time"

	"github.com/go-redis/redis/v8"
	"go.mongodb.org/mongo-driver/bson"
	"repositories.action2quare.com/ayo/gocommon"
	"repositories.action2quare.com/ayo/gocommon/logger"
)

type sessionRedis struct {
	*Authorization
	expireAt time.Time
}

type consumer_redis struct {
	consumer_common[sessionRedis]
	redisClient *redis.Client
}

func NewConsumerWithRedis(ctx context.Context, redisUrl string, ttl time.Duration) (Consumer, error) {
	redisClient, err := gocommon.NewRedisClient(redisUrl)
	if err != nil {
		return nil, err
	}

	consumer := &consumer_redis{
		consumer_common: consumer_common[sessionRedis]{
			ttl:       ttl,
			ctx:       ctx,
			stages:    [2]*cache_stage[sessionRedis]{make_cache_stage[sessionRedis](), make_cache_stage[sessionRedis]()},
			startTime: time.Now(),
		},
		redisClient: redisClient,
	}

	updateChannel := communication_channel_name_prefix + "_u"
	deleteChannel := communication_channel_name_prefix + "_d"
	sub := redisClient.Subscribe(ctx, updateChannel, deleteChannel)

	go func() {
		stageswitch := time.Now().Add(ttl)
		tickTimer := time.After(ttl)

		for {
			select {
			case <-ctx.Done():
				return

			case <-tickTimer:
				consumer.changeStage()
				stageswitch = stageswitch.Add(ttl)
				tempttl := time.Until(stageswitch)
				tickTimer = time.After(tempttl)

			case msg := <-sub.Channel():
				if msg == nil {
					return
				}

				if len(msg.Payload) == 0 {
					continue
				}

				switch msg.Channel {
				case updateChannel:
					key := msg.Payload
					raw, err := redisClient.Get(ctx, key).Result()
					if err != nil {
						logger.Println(err)
					} else if len(raw) > 0 {
						var si Authorization
						if bson.Unmarshal([]byte(raw), &si) == nil {
							consumer.add(key, sessionRedis{
								Authorization: &si,
								expireAt:      time.Now().Add(consumer.ttl),
							})
						}
					}
				case deleteChannel:
					key := msg.Payload
					consumer.delete(key)
				}
			}
		}
	}()

	return consumer, nil
}

func (c *consumer_redis) Query(key string) *Authorization {
	c.lock.Lock()
	defer c.lock.Unlock()

	if _, deleted := c.stages[0].deleted[key]; deleted {
		return nil
	}

	if _, deleted := c.stages[1].deleted[key]; deleted {
		return nil
	}

	found, ok := c.stages[0].cache[key]
	if !ok {
		found, ok = c.stages[1].cache[key]
	}

	if ok {
		if found.expireAt.After(time.Now()) {
			return found.Authorization
		}
	}

	payload, err := c.redisClient.Get(c.ctx, key).Result()
	if err == redis.Nil {
		return nil
	} else if err != nil {
		logger.Println("consumer Query :", err)
		return nil
	}

	if len(payload) > 0 {
		var si Authorization
		if bson.Unmarshal([]byte(payload), &si) == nil {
			ttl, err := c.redisClient.TTL(c.ctx, key).Result()
			if err != nil {
				logger.Println("consumer Query :", err)
				return nil
			}

			c.add_internal(key, sessionRedis{
				Authorization: &si,
				expireAt:      time.Now().Add(ttl),
			})
			return &si
		}
	}
	return nil
}

func (c *consumer_redis) Touch(key string) bool {
	c.lock.Lock()
	defer c.lock.Unlock()

	ok, err := c.redisClient.Expire(c.ctx, key, c.ttl).Result()
	if err == redis.Nil {
		return false
	} else if err != nil {
		logger.Println("consumer Touch :", err)
		return false
	}

	if ok {
		newexpire := time.Now().Add(c.ttl)
		found, ok := c.stages[0].cache[key]
		if ok {
			found.expireAt = newexpire
		}

		found, ok = c.stages[1].cache[key]
		if ok {
			found.expireAt = newexpire
		}
	}

	return ok
}