From 5aef2303c8d54eb804195b960300795284980a67 Mon Sep 17 00:00:00 2001
From: Muthu Kumar <muthukumar@thefeathers.in>
Date: Tue, 17 Jul 2018 13:37:09 +0530
Subject: [PATCH] [refactor] Added sessionFinder

---
 app.js               | 44 ++++++++++++++++++++------------------------
 lib/sessionFinder.js | 12 ++++++++++++
 util/index.js        |  4 ++--
 3 files changed, 34 insertions(+), 26 deletions(-)
 create mode 100644 lib/sessionFinder.js

diff --git a/app.js b/app.js
index 4ad7511..e9474b3 100644
--- a/app.js
+++ b/app.js
@@ -9,12 +9,10 @@ const Telegraf = require('telegraf');
 //Config
 const config = require('./config.js');
 
-// Utils
-const { path, getText, extractCommand } = require('./util/index.js');
-
 // Lib
 const validator = require('./lib/validator.js');
 const responder = require('./lib/responseHandler.js');
+const sessionFinder = require('./lib/sessionFinder.js');
 const listeners = require('./lib/listeners.js');
 
 const dateOptions = {
@@ -28,8 +26,11 @@ const dateOptions = {
 
 const bot = new Telegraf(config.botApiKey);
 const sessions = [];
+let identifierState = 0;
 sessions.history = [];
 
+const getSession = sessionFinder(sessions);
+
 bot.use((ctx, next) =>
 	validator(ctx)
 		.then(next)
@@ -48,7 +49,9 @@ bot.command('start',
 		const newProc = spawn(defaultShell, {
 			cwd: home
 		});
-		sessions.push(newProc);
+		newProc.identifier = identifierState;
+		sessions[identifierState] = newProc;
+		identifierState++;
 		sessions.currentSession = newProc;
 		listeners.add(sessions.currentSession, responder, ctx);
 		return ctx.replyWithHTML(`Welcome to tsh -- <code>Telegram Shell!</code>\n\n`
@@ -65,39 +68,32 @@ bot.command('ls',
 
 bot.command('attach',
 	ctx => {
-		const text = getText(ctx);
-		const sessionIndex = parseInt(extractCommand('attach')(text));
-		if(Number.isNaN(sessionIndex) || !sessions[sessionIndex])
+		const session = getSession(ctx)('attach');
+		if(!session)
 			return responder.fail('Session not found. /ls for list of sessions')(ctx);
-		sessions.currentSession = sessions[sessionIndex];
+		sessions.currentSession = session;
 		listeners.add(sessions.currentSession, responder, ctx);
-		return responder.success(`Reattached to shell ${sessionIndex}`)(ctx);
+		return responder.success(`Reattached to shell ${session.identifier}`)(ctx);
 	});
 
 bot.command('detach',
 	ctx => {
-		const text = getText(ctx);
-		const sessionIndex = parseInt(extractCommand('detach')(text));
-		const currentSession =
-			text.trim() === '/detach'
-				? sessions.currentSession : sessions[sessionIndex];
-		if(!currentSession)
+		const session = getSession(ctx)('detach') || sessions.currentSession;
+		if(!session)
 			return responder.fail('Session not found. /ls for list of sessions.')(ctx);
-		listeners.remove(sessions.currentSession);
+		listeners.remove(session);
 		sessions.currentSession = undefined;
-		return responder.success(`Detached from shell ${sessionIndex}`)(ctx);
+		return responder.success(`Detached from shell ${session.identifier}`)(ctx);
 	});
 
 bot.command('kill',
 	ctx => {
-		const text = getText(ctx);
-		const sessionIndex = parseInt(extractCommand('kill')(text));
-		if(Number.isNaN(sessionIndex) || !sessions[sessionIndex])
+		const session = getSession(ctx)('kill') || sessions.currentSession;
+		if(!session)
 			return responder.fail('Session not found. /ls for list of sessions.')(ctx);
-		const disconnect = sessions[sessionIndex];
-		delete sessions[sessionIndex];
-		if(disconnect === sessions.currentSession) sessions.currentSession = undefined;
-		disconnect.kill();
+		delete sessions[session.identifier];
+		if(session === sessions.currentSession) sessions.currentSession = undefined;
+		session.kill();
 		ctx.reply('Session killed. /ls for list of sessions.')
 	})
 
diff --git a/lib/sessionFinder.js b/lib/sessionFinder.js
new file mode 100644
index 0000000..a086385
--- /dev/null
+++ b/lib/sessionFinder.js
@@ -0,0 +1,12 @@
+const { compose, getText, extractCommandText } = require('../util/index.js');
+
+const sessionFinder = sessions => ctx => command => {
+	const identifier = compose(
+		extractCommandText(command),
+		getText,
+	)(ctx);
+
+	return sessions[identifier];
+};
+
+module.exports = sessionFinder;
\ No newline at end of file
diff --git a/util/index.js b/util/index.js
index d8466b8..934ce60 100644
--- a/util/index.js
+++ b/util/index.js
@@ -1,11 +1,11 @@
 const path = (path, obj) => path.reduce((result, segment) => result && result[segment], obj);
 const compose = (...fns) => fns.reduce((f, g) => (...args) => f(g(...args)));
 const getText = ctx => path(['update', 'message', 'text'], ctx) || '';
-const extractCommand = cmd => text => text.replace(`/${cmd}`, '').trim();
+const extractCommandText = cmd => text => text.replace(`/${cmd}`, '').trim();
 
 module.exports = {
 	path,
 	compose,
 	getText,
-	extractCommand,
+	extractCommandText,
 };