package main

import (
	"github.com/gomodule/redigo/redis"
	"log"
	"time"
)

var globalPool *redis.Pool

const alertsentPrefix string = "alertsent:"
const devPrefix string = "dev:"

func newPool() *redis.Pool {
	return &redis.Pool{
		// Maximum number of idle connections in the pool.
		MaxIdle: 80,
		// max number of connections
		MaxActive: 12000,
		// Dial is an application supplied function for creating and
		// configuring a connection.
		Dial: func() (redis.Conn, error) {
			c, err := redis.Dial("tcp", ":6379")
			if err != nil {
				panic(err.Error())
			}
			return c, err
		},
	}
}

// ping tests connectivity for redis (PONG should be returned)
func ping(c redis.Conn) error {
	// Send PING command to Redis
	// PING command returns a Redis "Simple String"
	// Use redis.String to convert the interface type to string
	_, err := redis.String(c.Do("PING"))
	if err != nil {
		return err
	}

	return nil
}

func initDB() {

	// newPool returns a pointer to a redis.Pool
	pool := newPool()
	// get a connection from the globalPool (redis.Conn)
	conn := pool.Get()
	defer conn.Close()

	globalPool = pool

	// wir machen einen Connection Test
	ping(conn)
}

func closeDB() {
	globalPool.Close()
}

func getActiveUntil(deveui string) string {
	res := ""

	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	activeuntil, err := redis.String(conn.Do("HGET", devPrefix+deveui, "active_until"))
	if err == nil {
		res = activeuntil
	} else {
		log.Print(err)
	}

	return res
}

func AboExpired(deveui string) bool {
	active_until := getActiveUntil(deveui)

	layout := "02.01.2006"
	t, _ := time.Parse(layout, active_until)

	return t.Before(time.Now())
}

func checkDevExists(deveui string) bool {
	conn := globalPool.Get()
	defer conn.Close()

	_, err := redis.String(conn.Do("GET", devPrefix+deveui))
	if err == redis.ErrNil {
		return false
	} else if err != nil {
		return true
	}
	return false
}

func getDevAlias(deveui string) string {
	res := deveui

	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	alias, err := redis.String(conn.Do("HGET", devPrefix+deveui, "alias"))
	if err == nil {
		res = alias
	} else {
		res = deveui
	}

	return res
}

func getDevSmsAlarmactive(deveui string) string {
	res := "0"

	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	smsalarmactive, err := redis.String(conn.Do("HGET", devPrefix+deveui, "smsalarmactive"))
	if err == nil {
		res = smsalarmactive
	}

	return res
}

func getSmsnumber(deveui string) string {
	res := ""
	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	smsnumber, err := redis.String(conn.Do("HGET", devPrefix+deveui, "smsnumber"))
	if err == nil {
		res = smsnumber
	}

	return res
}

func getDevEmailAlarmactive(deveui string) string {
	res := "0"

	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	emailalarmactive, err := redis.String(conn.Do("HGET", devPrefix+deveui, "emailalarmactive"))
	if err == nil {
		res = emailalarmactive
	}

	return res
}

func getEmail(deveui string) string {
	res := ""
	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	email, err := redis.String(conn.Do("HGET", devPrefix+deveui, "email"))
	if err == nil {
		res = email
	}

	return res
}

func getDevGreenzone(deveui string) string {
	res := ""

	if deveui == "" {
		return res
	}

	conn := globalPool.Get()
	defer conn.Close()

	greenzone, err := redis.String(conn.Do("HGET", devPrefix+deveui, "greenzone"))
	if err == nil {
		res = greenzone
	} else {
		log.Print(err)
	}

	return res
}

func AlertAlreadySentRecently(deveui string, what string) bool {
	conn := globalPool.Get()
	defer conn.Close()

	exists, _ := redis.Bool(conn.Do("EXISTS", alertsentPrefix+deveui+":"+what))
	return exists
}

func AddAlertAlreadySentRecently(deveui string, what string) {
	conn := globalPool.Get()
	defer conn.Close()
	expire_duration := 120
	if what == "alert_greenzone" {
		expire_duration = 7 * 24 * 60 * 60
	}

	_, err := conn.Do("SET", alertsentPrefix+deveui+":"+what, "1")

	if err != nil {
		return
	}

	// we set an expiration time to prevent duplicate alerts
	_, err1 := conn.Do("EXPIRE", alertsentPrefix+deveui+":"+what, expire_duration)

	if err1 != nil {
		return
	}

}

func DeleteGreenzoneAlert(deveui string) bool {
	conn := globalPool.Get()
	defer conn.Close()

	_, err := conn.Do("DEL", alertsentPrefix+deveui+":alert_greenzone")
	if err != nil {
		return false
	}

	return true

}