package db

import (
	"fmt"
	"github.com/go-redis/redis"
)

const NONCE = "go-tiny-url"

var domain = "data"

type db redis.Client

// Returns a connected client to dataset
func Connect() *db {
	cli := redis.NewClient(&redis.Options{
		Addr:     "127.0.0.1:6379",
		Password: "",
		DB:       0,
	})

	if _, err := cli.Ping().Result(); err != nil {
		return nil
	}

	return (*db)(cli)
}

// returns value from key (nil if nothing)
func (c *db) Get(key string) []byte {

	// 1. Try to get
	if val, err := (*redis.Client)(c).Get(fmt.Sprintf("%s:%s:%s", NONCE, domain, key)).Result(); err != nil {
		// 2. nil if nothing found
		return nil
	} else {
		// 3. return if found
		return []byte(val)
	}

}

// stores a value for a key (success state in return)
func (c *db) Set(key string, value string) bool {

	// 1. Try to set
	if (*redis.Client)(c).Set(fmt.Sprintf("%s:%s:%s", NONCE, domain, key), value, 0).Err() != nil {
		// 2. failure
		return false
	}

	// 3. success
	return true

}

// deletes the value for a key (success state in return)
func (c *db) Del(key string) bool {

	// 1. Try to set
	if (*redis.Client)(c).Del(fmt.Sprintf("%s:%s:%s", NONCE, domain, key)).Err() != nil {
		// 2. failure
		return false
	}

	// 3. success
	return true

}

// Switch following operations to DATA dataset
func (c *db) SwitchData() { domain = "data" }

// Switch following operations to AUTH dataset
func (c *db) SwitchAuth() { domain = "auth" }