ergo/irc/cef.go

package irc

import (
	"context"
	"crypto/sha256"
	"encoding/json"
	"fmt"
	"github.com/cshum/imagor/imagorpath"
	"github.com/ergochat/ergo/irc/caps"
	"github.com/ergochat/irc-go/ircmsg"
	"net/http"
	"regexp"
	"strings"
	"time"
)

var ctx = context.Background()

func (channel *Channel) RedisBroadcast(message ...string) {
	if channel.server.redis == nil {
		return
	}
	err := channel.server.redis.Publish(ctx, "channel."+channel.NameCasefolded(), strings.Join(message, " ")).Err()
	if err != nil {
		fmt.Printf("Channel broadcast error: %v", err)
	}
}

func (client *Client) RedisBroadcast(message ...string) {
	err := client.server.redis.Publish(ctx, "user."+client.NickCasefolded(), strings.Join(message, " ")).Err()
	if err != nil {
		fmt.Printf("User broadcast error: %v", err)
	}
}

func (channel *Channel) Broadcast(command string, params ...string) {
	channel.BroadcastFrom(channel.server.name, command, params...)
}

func (channel *Channel) BroadcastFrom(prefix string, command string, params ...string) {
	for _, member := range channel.Members() {
		for _, session := range member.Sessions() {
			session.Send(nil, prefix, command, params...)
		}
	}
}

// ChannelSub Actions and info centering around channels
func (server *Server) ChannelSub() {
	pubsub := server.redis.PSubscribe(ctx, "channel.*")
	defer pubsub.Close()

	ch := pubsub.Channel()

	for msg := range ch {
		server.logger.Info("RedisMessage", msg.Channel, msg.Payload)
		line := strings.Split(msg.Payload, " ")
		channelName := strings.SplitN(msg.Channel, ".", 2)[1]
		channel := server.channels.Get(channelName)
		if len(line) == 0 {
			println("Empty string dumped into ", msg.Channel, " channel")
		}
		if channel == nil {
			server.logger.Warning("RedisMessage", "Unknown channel")
			continue
		}

		switch line[0] {
		case "VOICEPART":
			channel.Broadcast("VOICEPART", channelName, line[1])
		case "VOICESTATE":
			channel.Broadcast("VOICESTATE", channelName, line[1])
		case "BROADCASTTO":
			for _, person := range channel.Members() {
				person.Send(nil, server.name, line[1], line[2:]...)
			}
		}
	}
}

// UserSub Handles things pertaining to users
func (server *Server) UserSub() {
	pubsub := server.redis.PSubscribe(ctx, "user.*")
	defer pubsub.Close()

	ch := pubsub.Channel()

	for msg := range ch {
		server.logger.Info("RedisMessage", msg.Channel, msg.Payload)
		line := strings.Split(msg.Payload, " ")
		userName := strings.SplitN(msg.Channel, ".", 2)[1]
		user := server.clients.Get(userName)
		if len(line) == 0 {
			println("Empty string dumped into ", msg.Channel, " channel")
		}

		switch line[0] {
		case "FULLYREMOVE":
			if user != nil {
				user.destroy(nil)
				err := server.accounts.Unregister(user.Account(), true)
				if err != nil {
					return
				}
			}
			break
		case "BROADCASTAS":
			if user != nil {
				// I'm not too sure what the capability bit is, I think it's just ones that match
				for friend := range user.Friends(caps.ExtendedNames) {
					friend.Send(nil, user.NickMaskString(), line[1], line[2:]...)
				}
			}
			break
		}
	}
}

func startRedis(server *Server) {
	go server.ChannelSub()
	go server.UserSub()
}

func (server *Server) GenerateImagorSignaturesFromMessage(message *ircmsg.Message) string {
	line, err := message.Line()
	if err == nil {
		return server.GenerateImagorSignatures(line)
	}
	return ""
}

func (server *Server) GetUrlMime(url string) string {
	config := server.Config()
	// hacky, should fix
	if !strings.Contains(url, "?") {
		url += "?"
	}
	params := imagorpath.Params{
		Image: url,
		Meta:  true,
	}
	metaPath := imagorpath.Generate(params, imagorpath.NewHMACSigner(sha256.New, 0, config.Cef.Imagor.Secret))
	client := http.Client{
		Timeout: 5 * time.Second,
	}
	resp, err := client.Get(config.Cef.Imagor.Url + metaPath)
	if err != nil {
		println("Failed on the initial get")
		println(err.Error())
		return ""
	}
	defer resp.Body.Close()
	var meta map[string]interface{}
	err = json.NewDecoder(resp.Body).Decode(&meta)
	if err != nil {
		println("Failed on the JSON decode")
		return ""
	}
	contentType, valid := meta["format"].(string)
	if !valid {
		println("No content type")
		return ""
	}
	return contentType
}

var urlRegex = regexp.MustCompile("https?:\\/\\/[\\w-]+(\\.[\\w-]+)+([\\w.,@?^=%&:/~+#-]*[\\w@?^=%&/~+#-])?")

// Process a message to add Imagor signatures
func (server *Server) GenerateImagorSignatures(str string) string {
	urls := urlRegex.FindAllString(str, -1)
	var sigs []string
	for _, url := range urls {
		params := imagorpath.Params{
			Image:  url,
			FitIn:  true,
			Width:  600,
			Height: 600,
		}
		path := imagorpath.Generate(params, imagorpath.NewHMACSigner(sha256.New, 0, server.Config().Cef.Imagor.Secret))
		signature := path[:strings.IndexByte(path, '/')]
		contentType := server.GetUrlMime(url)
		if contentType != "" {
			sigs = append(sigs, signature+"|"+strings.ReplaceAll(contentType, "/", "_"))
		} else {
			sigs = append(sigs, signature)
		}

	}
	if len(sigs) > 0 {
		return strings.Join(sigs, ",")
	}
	return ""
}