package cmd

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"net"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/ethereum/go-ethereum/crypto"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"
	"github.com/status-im/go-waku/waku/v2/node"
	"github.com/status-im/go-waku/waku/v2/protocol"
	store "github.com/status-im/go-waku/waku/v2/protocol/waku_store"
)

func randomHex(n int) (string, error) {
	bytes := make([]byte, n)
	if _, err := rand.Read(bytes); err != nil {
		return "", err
	}
	return hex.EncodeToString(bytes), nil
}

func write(wakuNode *node.WakuNode, msgContent string) {

	var contentTopic uint32 = 1
	var version uint32 = 0

	payload, err := node.Encode([]byte(wakuNode.ID()+" says "+msgContent), &node.KeyInfo{Kind: node.None}, 0)
	msg := &protocol.WakuMessage{Payload: payload, Version: &version, ContentTopic: &contentTopic}
	err = wakuNode.Publish(msg, nil)
	if err != nil {
		fmt.Println("Error sending a message", err)
	} else {
		fmt.Println("Message sent...")
	}
}

func writeLoop(wakuNode *node.WakuNode) {
	for {
		time.Sleep(2 * time.Second)
		write(wakuNode, fmt.Sprint("Hey - ", time.Now().Unix()))
	}
}

func readLoop(wakuNode *node.WakuNode) {
	sub, err := wakuNode.Subscribe(nil)
	if err != nil {
		fmt.Println("Could not subscribe:", err)
		return
	}

	for value := range sub.C {
		payload, err := node.DecodePayload(value.Message(), &node.KeyInfo{Kind: node.None})
		if err != nil {
			fmt.Println(err)
			return
		}
		fmt.Println("Received message:", string(payload))
	}
}

type DBStore struct {
	store.MessageProvider
}

func (dbStore *DBStore) Put(message *protocol.WakuMessage) error {
	fmt.Println("TODO: Implement MessageProvider.Put")
	return nil
}

func (dbStore *DBStore) GetAll() ([]*protocol.WakuMessage, error) {
	fmt.Println("TODO: Implement MessageProvider.GetAll. Returning a sample message")
	exampleMessage := new(protocol.WakuMessage)
	var contentTopic uint32 = 1
	var version uint32 = 0
	exampleMessage.ContentTopic = &contentTopic
	exampleMessage.Payload = []byte("Hello!")
	exampleMessage.Version = &version

	return []*protocol.WakuMessage{exampleMessage}, nil
}

var rootCmd = &cobra.Command{
	Use:   "waku",
	Short: "Start a waku node",
	Long:  `Start a waku node...`,
	// Uncomment the following line if your bare application
	// has an action associated with it:
	Run: func(cmd *cobra.Command, args []string) {
		port, _ := cmd.Flags().GetInt("port")
		relay, _ := cmd.Flags().GetBool("relay")
		key, _ := cmd.Flags().GetString("nodekey")
		store, _ := cmd.Flags().GetBool("store")
		startStore, _ := cmd.Flags().GetBool("start-store")
		storenode, _ := cmd.Flags().GetString("storenode")
		staticnodes, _ := cmd.Flags().GetStringSlice("staticnodes")
		query, _ := cmd.Flags().GetBool("query")

		hey, _ := cmd.Flags().GetBool("hey")
		listen, _ := cmd.Flags().GetBool("listen")
		say, _ := cmd.Flags().GetString("say")

		hostAddr, _ := net.ResolveTCPAddr("tcp", fmt.Sprint("0.0.0.0:", port))

		if key == "" {
			var err error
			key, err = randomHex(32)
			if err != nil {
				fmt.Println("Could not generate random key")
				return
			}
		}

		prvKey, err := crypto.HexToECDSA(key)

		ctx := context.Background()
		wakuNode, err := node.New(ctx, prvKey, []net.Addr{hostAddr})
		if err != nil {
			fmt.Print(err)
			return
		}

		if relay {
			wakuNode.MountRelay()
		}

		if store {
			wakuNode.MountStore(new(DBStore))
		}

		if startStore {
			if !store {
				fmt.Println("Store protocol was not started")
				return
			}
			wakuNode.StartStore()
		}

		if storenode != "" && !store {
			fmt.Println("Store protocol was not started")
			return
		} else {
			if storenode != "" {
				wakuNode.AddStorePeer(storenode)
			}
		}

		if len(staticnodes) > 0 {
			for _, n := range staticnodes {
				go wakuNode.DialPeer(n)
			}
		}

		if hey {
			go writeLoop(wakuNode)
		}

		if listen {
			go readLoop(wakuNode)
		}

		if say != "" {
			go write(wakuNode, say)
		}

		if query {
			if !store {
				fmt.Println("Store protocol was not started")
				return
			}

			response, err := wakuNode.Query(1, true, 10)
			if err != nil {
				fmt.Println(err)
				return
			}

			fmt.Println(fmt.Sprint("Page Size: ", response.PagingInfo.PageSize))
			fmt.Println(fmt.Sprint("Direction: ", response.PagingInfo.Direction))
			fmt.Println(fmt.Sprint("Cursor - ReceivedTime: ", response.PagingInfo.Cursor.ReceivedTime))
			fmt.Println(fmt.Sprint("Cursor - Digest: ", hex.EncodeToString(response.PagingInfo.Cursor.Digest)))
			fmt.Println("Messages:")
			for i, msg := range response.Messages {
				fmt.Println(fmt.Sprint(i, "- ", string(msg.Payload))) // Normaly you'd have to decode these, but i'm using v0
			}
		}

		// Wait for a SIGINT or SIGTERM signal
		ch := make(chan os.Signal, 1)
		signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
		<-ch
		fmt.Println("\n\n\nReceived signal, shutting down...")

		// shut the node down
		wakuNode.Stop()
	},
}

// Execute adds all child commands to the root command and sets flags appropriately.
// This is called by main.main(). It only needs to happen once to the rootCmd.
func Execute() {
	cobra.CheckErr(rootCmd.Execute())
}

func init() {
	cobra.OnInitialize(initConfig)

	rootCmd.Flags().Int("port", 9000, "Libp2p TCP listening port (0 for random)")
	rootCmd.Flags().String("nodekey", "", "P2P node private key as hex (default random)")
	rootCmd.Flags().StringSlice("staticnodes", []string{}, "Multiaddr of peer to directly connect with. Argument may be repeated")
	rootCmd.Flags().Bool("store", false, "Enable store protocol")
	rootCmd.Flags().Bool("start-store", false, "Store messages")
	rootCmd.Flags().String("storenode", "", "Multiaddr of peer to connect with for waku store protocol")
	rootCmd.Flags().Bool("relay", true, "Enable relay protocol")
	rootCmd.Flags().Bool("hey", false, "Send \"hey!\" on default topic every 2 seconds")
	rootCmd.Flags().String("say", "", "Broadcast a message on default topic")
	rootCmd.Flags().Bool("listen", false, "Listen messages on default topic")
	rootCmd.Flags().Bool("query", false, "Asks the storenode for stored messages")

}

func initConfig() {
	viper.AutomaticEnv() // read in environment variables that match
}