From 87df2040e4dfafd7114e0eca389180eb7ef7c2f7 Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Wed, 29 Sep 2021 18:23:29 +0200
Subject: [PATCH] [templating] Add botHasBadge function

to allow checking for moderation permissions in channels

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 botUserState.go  | 71 ++++++++++++++++++++++++++++++++++++++++++++++++
 functions_irc.go |  6 ++++
 irc.go           | 15 ++++++++++
 main.go          |  7 +++--
 4 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 botUserState.go

diff --git a/botUserState.go b/botUserState.go
new file mode 100644
index 0000000..5aa2e51
--- /dev/null
+++ b/botUserState.go
@@ -0,0 +1,71 @@
+package main
+
+import (
+	"strconv"
+	"strings"
+	"sync"
+
+	"github.com/Luzifer/twitch-bot/twitch"
+	"github.com/go-irc/irc"
+	"github.com/pkg/errors"
+)
+
+type (
+	twitchUserState struct {
+		Badges      twitch.BadgeCollection
+		Color       string
+		DisplayName string
+		EmoteSets   []int64
+	}
+
+	twitchUserStateStore struct {
+		states map[string]*twitchUserState
+		lock   sync.RWMutex
+	}
+)
+
+func newTwitchUserStateStore() *twitchUserStateStore {
+	return &twitchUserStateStore{
+		states: make(map[string]*twitchUserState),
+	}
+}
+
+func parseTwitchUserState(m *irc.Message) (*twitchUserState, error) {
+	var (
+		color, _       = m.GetTag("color")
+		displayName, _ = m.GetTag("display-name")
+		emoteSets      []int64
+		rawSets, _     = m.GetTag("emote-sets")
+	)
+
+	if rawSets != "" {
+		for _, sid := range strings.Split(rawSets, ",") {
+			id, err := strconv.ParseInt(sid, 10, 64)
+			if err != nil {
+				return nil, errors.Wrap(err, "parsing emote-set id")
+			}
+			emoteSets = append(emoteSets, id)
+		}
+	}
+
+	return &twitchUserState{
+		Badges:      twitch.ParseBadgeLevels(m),
+		Color:       color,
+		DisplayName: displayName,
+		EmoteSets:   emoteSets,
+	}, nil
+}
+
+func (t *twitchUserStateStore) Get(channel string) *twitchUserState {
+	t.lock.RLock()
+	defer t.lock.RUnlock()
+
+	return t.states[channel]
+}
+
+func (t *twitchUserStateStore) Set(channel string, state *twitchUserState) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	t.states[channel] = state
+}
diff --git a/functions_irc.go b/functions_irc.go
index f34062a..efbfd54 100644
--- a/functions_irc.go
+++ b/functions_irc.go
@@ -20,6 +20,12 @@ func init() {
 		}
 	})
 
+	tplFuncs.Register("botHasBadge", func(m *irc.Message, r *plugins.Rule, fields map[string]interface{}) interface{} {
+		return func(badge string) bool {
+			return botUserstate.Get(plugins.DeriveChannel(m, nil)).Badges.Has(badge)
+		}
+	})
+
 	tplFuncs.Register("fixUsername", plugins.GenericTemplateFunctionGetter(func(username string) string { return strings.TrimLeft(username, "@#") }))
 
 	tplFuncs.Register("group", func(m *irc.Message, r *plugins.Rule, fields map[string]interface{}) interface{} {
diff --git a/irc.go b/irc.go
index df5652b..7a7340c 100644
--- a/irc.go
+++ b/irc.go
@@ -145,6 +145,11 @@ func (i ircHandler) Handle(c *irc.Client, m *irc.Message) {
 		// Announces Twitch-specific events to the channel (for example, a user’s subscription notification).
 		i.handleTwitchUsernotice(m)
 
+	case "USERSTATE":
+		// USERSTATE (Twitch Tags)
+		// Sends user-state data when a user joins a channel or sends a PRIVMSG to a channel.
+		i.handleTwitchUserstate(m)
+
 	case "WHISPER":
 		// WHISPER (Twitch Commands)
 		// Delivers whisper-messages received
@@ -281,6 +286,16 @@ func (i ircHandler) handleTwitchUsernotice(m *irc.Message) {
 	}
 }
 
+func (i ircHandler) handleTwitchUserstate(m *irc.Message) {
+	state, err := parseTwitchUserState(m)
+	if err != nil {
+		log.WithError(err).Error("Unable to parse bot user-state")
+		return
+	}
+
+	botUserstate.Set(plugins.DeriveChannel(m, nil), state)
+}
+
 func (i ircHandler) handleTwitchWhisper(m *irc.Message) {
 	go handleMessage(i.c, m, eventTypeWhisper, nil)
 }
diff --git a/main.go b/main.go
index d19b6b2..9809792 100644
--- a/main.go
+++ b/main.go
@@ -40,9 +40,10 @@ var (
 	config     *configFile
 	configLock = new(sync.RWMutex)
 
-	cronService *cron.Cron
-	ircHdl      *ircHandler
-	router      = mux.NewRouter()
+	botUserstate = newTwitchUserStateStore()
+	cronService  *cron.Cron
+	ircHdl       *ircHandler
+	router       = mux.NewRouter()
 
 	sendMessage func(m *irc.Message) error