From d49dc9b0ff799f5bdff4c524bee6531b3fdce9eb Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Mon, 12 Jul 2021 18:04:31 +0200
Subject: [PATCH] Add stream schedule module

---
 env.go                |  11 ++++
 mod_streamSchedule.go | 130 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 141 insertions(+)
 create mode 100644 env.go
 create mode 100644 mod_streamSchedule.go

diff --git a/env.go b/env.go
new file mode 100644
index 0000000..0e72379
--- /dev/null
+++ b/env.go
@@ -0,0 +1,11 @@
+package main
+
+import "os"
+
+var (
+	discordAnnouncementChannel = os.Getenv("DISCORD_ANNOUNCEMENT_CHANNEL")
+	discordLiveChannel         = os.Getenv("DISCORD_LIVE_CHANNEL")
+	twitchChannelID            = os.Getenv("TWITCH_CHANNEL_ID")
+	twitchClientID             = os.Getenv("TWITCH_CLIENT_ID")
+	twitchToken                = os.Getenv("TWITCH_TOKEN")
+)
diff --git a/mod_streamSchedule.go b/mod_streamSchedule.go
new file mode 100644
index 0000000..ff9742d
--- /dev/null
+++ b/mod_streamSchedule.go
@@ -0,0 +1,130 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/Luzifer/go_helpers/v2/backoff"
+	"github.com/bwmarrin/discordgo"
+	"github.com/pkg/errors"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	twitchAPIRequestLimit   = 5
+	twitchAPIRequestTimeout = 2 * time.Second
+	streamScheduleEntries   = 5
+)
+
+type twitchStreamScheduleResponse struct {
+	Data struct {
+		Segments []struct {
+			ID            string     `json:"id"`
+			StartTime     *time.Time `json:"start_time"`
+			EndTime       *time.Time `json:"end_time"`
+			Title         string     `json:"title"`
+			CanceledUntil *time.Time `json:"canceled_until"`
+			Category      *struct {
+				ID   string `json:"id"`
+				Name string `json:"name"`
+			} `json:"category"`
+			IsRecurring bool `json:"is_recurring"`
+		} `json:"segments"`
+		BroadcasterID    string `json:"broadcaster_id"`
+		BroadcasterName  string `json:"broadcaster_name"`
+		BroadcasterLogin string `json:"broadcaster_login"`
+		Vacation         *struct {
+			StartTime *time.Time `json:"start_time"`
+			EndTime   *time.Time `json:"end_time"`
+		} `json:"vacation"`
+	} `json:"data"`
+	Pagination struct {
+		Cursor string `json:"cursor"`
+	} `json:"pagination"`
+}
+
+func init() {
+	if _, err := crontab.AddFunc("*/5 * * * *", cronUpdateSchedule); err != nil {
+		log.WithError(err).Fatal("Unable to add cronUpdatePresence function")
+	}
+}
+
+func cronUpdateSchedule() {
+	var data twitchStreamScheduleResponse
+	if err := backoff.NewBackoff().WithMaxIterations(twitchAPIRequestLimit).Retry(func() error {
+		ctx, cancel := context.WithTimeout(context.Background(), twitchAPIRequestTimeout)
+		defer cancel()
+
+		req, _ := http.NewRequestWithContext(ctx, http.MethodGet, fmt.Sprintf("https://api.twitch.tv/helix/schedule?broadcaster_id=%s&first=%d", twitchChannelID, streamScheduleEntries), nil)
+		req.Header.Set("Authorization", "Bearer "+twitchToken)
+		req.Header.Set("Client-Id", twitchClientID)
+
+		resp, err := http.DefaultClient.Do(req)
+		if err != nil {
+			return errors.Wrap(err, "fetching schedule")
+		}
+		defer resp.Body.Close()
+
+		return errors.Wrap(
+			json.NewDecoder(resp.Body).Decode(&data),
+			"decoding schedule response",
+		)
+	}); err != nil {
+		log.WithError(err).Error("Unable to fetch stream schedule")
+		return
+	}
+
+	msgEmbed := &discordgo.MessageEmbed{
+		Color:       3066993,
+		Type:        discordgo.EmbedTypeRich,
+		Title:       "Fortlaufender Streamplan",
+		Description: "Streams sind bis ca. 23 Uhr / Mitternacht, geplant aber man weiss ja wie das mit Plänen und Theorien so funktioniert…",
+		Fields:      []*discordgo.MessageEmbedField{},
+		Thumbnail: &discordgo.MessageEmbedThumbnail{
+			URL:    "https://p.hub.luzifer.io/http://www.clker.com/cliparts/c/f/5/7/1194984495549320725tabella_architetto_franc_01.svg.hi.png",
+			Width:  600,
+			Height: 599,
+		},
+	}
+
+	for _, seg := range data.Data.Segments {
+		title := seg.Title
+		if seg.Category != nil && seg.Category.Name != seg.Title {
+			title = fmt.Sprintf("%s (%s)", seg.Title, seg.Category.Name)
+		}
+
+		msgEmbed.Fields = append(msgEmbed.Fields, &discordgo.MessageEmbedField{
+			Name:   seg.StartTime.Format("Mon 02.01. 15:04 Uhr"),
+			Value:  title,
+			Inline: false,
+		})
+	}
+
+	msgs, err := discord.ChannelMessages(discordAnnouncementChannel, 100, "", "", "")
+	if err != nil {
+		log.WithError(err).Error("Unable to fetch announcement channel messages")
+		return
+	}
+
+	var msgID string
+	for _, msg := range msgs {
+		if len(msg.Embeds) == 0 || msg.Embeds[0].Title != msgEmbed.Title {
+			continue
+		}
+
+		msgID = msg.ID
+	}
+
+	if msgID != "" {
+		_, err = discord.ChannelMessageEditEmbed(discordAnnouncementChannel, msgID, msgEmbed)
+	} else {
+		_, err = discord.ChannelMessageSendEmbed(discordAnnouncementChannel, msgEmbed)
+	}
+	if err != nil {
+		log.WithError(err).Error("Unable to announce streamplan")
+		return
+	}
+}