From ee03bde2dee3d412ebf1fc24b3745b260152e4b9 Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Sat, 21 Dec 2019 15:57:51 +0100
Subject: [PATCH] Add auto-reload on config change

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 cmd/streamdeck/config.go |  7 +++++++
 cmd/streamdeck/go.mod    |  1 +
 cmd/streamdeck/go.sum    |  2 ++
 cmd/streamdeck/main.go   | 40 +++++++++++++++++++++++++++++++++++++---
 4 files changed, 47 insertions(+), 3 deletions(-)

diff --git a/cmd/streamdeck/config.go b/cmd/streamdeck/config.go
index c0d17df..0354771 100644
--- a/cmd/streamdeck/config.go
+++ b/cmd/streamdeck/config.go
@@ -3,6 +3,7 @@ package main
 import "time"
 
 type config struct {
+	AutoReload        bool            `yaml:"auto_reload"`
 	DefaultBrightness int             `yaml:"default_brightness"`
 	DefaultPage       string          `yaml:"default_page"`
 	DisplayOffTime    time.Duration   `yaml:"display_off_time"`
@@ -24,3 +25,9 @@ type dynamicElement struct {
 	Type       string                 `yaml:"type"`
 	Attributes map[string]interface{} `yaml:"attributes"`
 }
+
+func newConfig() config {
+	return config{
+		AutoReload: true,
+	}
+}
diff --git a/cmd/streamdeck/go.mod b/cmd/streamdeck/go.mod
index c6967ff..5035c0b 100644
--- a/cmd/streamdeck/go.mod
+++ b/cmd/streamdeck/go.mod
@@ -7,6 +7,7 @@ replace github.com/Luzifer/streamdeck => ../../
 require (
 	github.com/Luzifer/rconfig/v2 v2.2.1
 	github.com/Luzifer/streamdeck v0.0.0-20191122003228-a2f524a6b22c
+	github.com/fsnotify/fsnotify v1.4.7
 	github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0
 	github.com/konsorten/go-windows-terminal-sequences v1.0.2 // indirect
 	github.com/pkg/errors v0.8.1
diff --git a/cmd/streamdeck/go.sum b/cmd/streamdeck/go.sum
index a845bd7..d6966bc 100644
--- a/cmd/streamdeck/go.sum
+++ b/cmd/streamdeck/go.sum
@@ -3,6 +3,8 @@ github.com/Luzifer/rconfig/v2 v2.2.1/go.mod h1:OKIX0/JRZrPJ/ZXXWklQEFXA6tBfWaljZ
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/disintegration/imaging v1.6.2 h1:w1LecBlG2Lnp8B3jk5zSuNqd7b4DXhcjwek1ei82L+c=
 github.com/disintegration/imaging v1.6.2/go.mod h1:44/5580QXChDfwIclfc/PCwrr44amcmDAg8hxG0Ewe4=
+github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
+github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0 h1:DACJavvAHhabrF08vX0COfcOBJRhZ8lUbR+ZWIs0Y5g=
 github.com/golang/freetype v0.0.0-20170609003504-e2365dfdc4a0/go.mod h1:E/TSTwGwJL78qG/PmXZO1EjYhfJinVAhrmmHX6Z8B9k=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1 h1:mweAR1A6xJ3oS2pRaGiHgQ4OO8tzTaLawm8vnODuwDk=
diff --git a/cmd/streamdeck/main.go b/cmd/streamdeck/main.go
index 5762bd0..38860c3 100644
--- a/cmd/streamdeck/main.go
+++ b/cmd/streamdeck/main.go
@@ -10,6 +10,7 @@ import (
 
 	"github.com/Luzifer/rconfig/v2"
 	"github.com/Luzifer/streamdeck"
+	"github.com/fsnotify/fsnotify"
 	"github.com/pkg/errors"
 	"github.com/sashko/go-uinput"
 	log "github.com/sirupsen/logrus"
@@ -25,9 +26,10 @@ var (
 
 	currentBrightness int
 
-	userConfig  config
-	activePage  page
-	activeLoops []refreshingDisplayElement
+	userConfig     config
+	activePage     page
+	activePageName string
+	activeLoops    []refreshingDisplayElement
 
 	sd *streamdeck.Client
 
@@ -135,6 +137,17 @@ func main() {
 		offTimer = time.NewTimer(userConfig.DisplayOffTime)
 	}
 
+	fswatch, err := fsnotify.NewWatcher()
+	if err != nil {
+		log.WithError(err).Fatal("Unable to create file watcher")
+	}
+
+	if userConfig.AutoReload {
+		if err = fswatch.Add(cfg.Config); err != nil {
+			log.WithError(err).Error("Unable to watch config, auto-reload will not work")
+		}
+	}
+
 	for {
 		select {
 		case evt := <-sd.Subscribe():
@@ -158,6 +171,26 @@ func main() {
 				log.WithError(err).Error("Unable to toggle to blank page")
 			}
 
+		case evt := <-fswatch.Events:
+			if evt.Op&fsnotify.Write == fsnotify.Write {
+				log.Info("Detected change of config, reloading")
+
+				if err := loadConfig(); err != nil {
+					log.WithError(err).Error("Unable to reload config")
+					continue
+				}
+
+				var nextPage = userConfig.DefaultPage
+				if _, ok := userConfig.Pages[activePageName]; ok {
+					nextPage = activePageName
+				}
+
+				if err := togglePage(nextPage); err != nil {
+					log.WithError(err).Error("Unable to reload page")
+					continue
+				}
+			}
+
 		case <-sigs:
 			return
 
@@ -175,6 +208,7 @@ func togglePage(page string) error {
 	activeLoops = nil
 
 	activePage = userConfig.Pages[page]
+	activePageName = page
 	sd.ClearAllKeys()
 
 	for idx, kd := range activePage.Keys {