package main

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

var globalPool *redis.Pool

const lastvaluesPrefix string = "lastvalues:"
const devPrefix string = "dev:"

type CalSettings struct {
	w1_0 int32
	w2_0 int32
	w1_c float32
	w2_c float32
}

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)

	addValue("0000000000000000", uint32(time.Now().Unix()))
}

func closeDB() {
	globalPool.Close()
}

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

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

func getMaxValue(deveui string) uint32 {
	var res uint32 = 0
	var myvalues []uint32
	conn := globalPool.Get()
	defer conn.Close()

	values, _ := redis.Values(conn.Do("LRANGE", lastvaluesPrefix+deveui, 0, -1))

	if err := redis.ScanSlice(values, &myvalues); err != nil {
		fmt.Println(err)
		return 0
	}

	for _, value := range myvalues {
		if uint32(value) > res {
			res = uint32(value)
		}
	}

	return res
}

func addValue(deveui string, value uint32) {
	conn := globalPool.Get()
	defer conn.Close()

	_, err := conn.Do("LPUSH", lastvaluesPrefix+deveui, value)

	if err != nil {
		return
	}

	_, err2 := conn.Do("LTRIM", lastvaluesPrefix+deveui, 0, 4)

	if err2 != nil {
		return
	}

	// we set an expiration time of three hours
	_, err3 := conn.Do("EXPIRE", lastvaluesPrefix+deveui, 10800)

	if err3 != nil {
		return
	}
}

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

	_, err := conn.Do("LTRIM", lastvaluesPrefix+deveui, 1, 0)

	if err != nil {
		return
	}
}

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 getDevAlarmactive(deveui string) string {
	res := "0"

	if deveui == "" {
		return res
	}

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

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

	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 getDevMinmax(deveui string) string {
	res := "0,0"

	if deveui == "" {
		return res
	}

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

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

	return res
}

func GetDownlinkCommand(deveui string) string {
	// 0: do nothing...
	res := "do_nothing"

	if deveui == "" {
		return res
	}

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

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

	return res
}

func SetMinMaxStatus(deveui string, status string) error {
	conn := globalPool.Get()
	defer conn.Close()

	// SET object
	_, err := conn.Do("HMSET", devPrefix+deveui, "minmaxstatus", status)
	if err != nil {
		return err
	}

	return nil
}

func GetMinMaxStatus(deveui string) string {
	res := "NORMAL"

	if deveui == "" {
		return res
	}

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

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

	return res
}

func SetDownlinkCommand(deveui string, new_command string) error {
	conn := globalPool.Get()
	defer conn.Close()

	// SET object
	_, err := conn.Do("HMSET", devPrefix+deveui, "downlink_command", new_command)
	if err != nil {
		return err
	}

	return nil
}

func GetCurrentCalibrationSettings(deveui string) CalSettings {
	var res CalSettings
	if deveui == "" {
		return res
	}

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

	s_w1_0, err := redis.String(conn.Do("HGET", devPrefix+deveui, "w1_0"))
	if err == nil {
		n, err := strconv.ParseInt(s_w1_0, 10, 32)
		if err == nil {
			res.w1_0 = int32(n)
		}
	}

	s_w2_0, err := redis.String(conn.Do("HGET", devPrefix+deveui, "w2_0"))
	if err == nil {
		n, err := strconv.ParseInt(s_w2_0, 10, 32)
		if err == nil {
			res.w2_0 = int32(n)
		}
	}

	s_w1_c, err := redis.String(conn.Do("HGET", devPrefix+deveui, "w1_c"))
	if err == nil {
		f, err := strconv.ParseFloat(s_w1_c, 32)
		if err == nil {
			res.w1_c = float32(f)
		}
	}

	s_w2_c, err := redis.String(conn.Do("HGET", devPrefix+deveui, "w2_c"))
	if err == nil {
		f, err := strconv.ParseFloat(s_w2_c, 32)
		if err == nil {
			res.w2_c = float32(f)
		}
	}

	return res
}

func SetCurrentCalibrationSettings(deveui string, cal_settings CalSettings) error {
	if deveui == "" {
		return nil
	}

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

	w1_0 := fmt.Sprintf("%d", cal_settings.w1_0)
	w2_0 := fmt.Sprintf("%d", cal_settings.w2_0)
	w1_c := fmt.Sprintf("%f", cal_settings.w1_c)
	w2_c := fmt.Sprintf("%f", cal_settings.w2_c)

	fmt.Printf("DEBUG SetCurrentCalibrationSettings: w1_0: %s, w2_0: %s, w1_c: %s, w2_c: %s\n", w1_0, w2_0, w1_c, w2_c)

	// SET object
	_, err := conn.Do("HMSET", devPrefix+deveui, "w1_0", w1_0, "w2_0", w2_0, "w1_c", w1_c, "w2_c", w2_c)
	if err != nil {
		return err
	}

	return nil
}