From 60d9084713942c719c7577ff644ae3397ab08b59 Mon Sep 17 00:00:00 2001
From: Jannis R <mail@jannisr.de>
Date: Sun, 1 Apr 2018 21:51:24 +0200
Subject: [PATCH] in groups, only react to mentions

---
 index.js                       |  3 +++
 lib/in-groups-only-mentions.js | 23 +++++++++++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 lib/in-groups-only-mentions.js

diff --git a/index.js b/index.js
index 9207712..a81c9d4 100644
--- a/index.js
+++ b/index.js
@@ -4,6 +4,7 @@ const path = require('path')
 const Bot = require('telegraf')
 const url = require('url')
 
+const inGroupsOnlyMentions = require('./lib/in-groups-only-mentions')
 const textWithoutMention = require('./lib/text-without-mention')
 const logging = require('./lib/logging')
 const session = require('./lib/session')
@@ -31,6 +32,8 @@ if (!TOKEN) {
 const pathToDb = path.join(__dirname, 'vbb-telegram.ldb')
 
 const bot = new Bot(TOKEN)
+
+bot.use(inGroupsOnlyMentions)
 bot.use(logging)
 bot.use(textWithoutMention)
 bot.use(session(pathToDb))
diff --git a/lib/in-groups-only-mentions.js b/lib/in-groups-only-mentions.js
new file mode 100644
index 0000000..3da78d0
--- /dev/null
+++ b/lib/in-groups-only-mentions.js
@@ -0,0 +1,23 @@
+'use strict'
+
+const HANDLE = process.env.HANDLE
+if (!HANDLE) {
+	console.error('Missing HANDLE env var.')
+	process.exit(1)
+}
+
+const mention = ('@' + HANDLE).toLowerCase()
+
+const inGroupsOnlyMentions = (ctx, next) => {
+	if (!ctx.chat || !ctx.chat.type || !ctx.message) return null
+	if (ctx.chat.type === 'group') {
+		const text = ctx.message.text
+		if (text) {
+			const i = text.toLowerCase().indexOf(mention)
+			if (i < 0) return null // no mention
+		}
+	}
+	next()
+}
+
+module.exports = inGroupsOnlyMentions