From e9aafd0cea6320582e4bb8042775f68ab11ba649 Mon Sep 17 00:00:00 2001
From: HeshamTB <hishaminv@gmail.com>
Date: Sat, 16 Sep 2023 04:56:32 +0300
Subject: [PATCH] feat: package updater

Signed-off-by: HeshamTB <hishaminv@gmail.com>
---
 apkupdater/apkupdater.go | 48 ++++++++++++++++++++++++++++++++++++++--
 main.go                  | 11 +++++++++
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/apkupdater/apkupdater.go b/apkupdater/apkupdater.go
index e0ae81d..3b7be44 100644
--- a/apkupdater/apkupdater.go
+++ b/apkupdater/apkupdater.go
@@ -9,7 +9,41 @@ import (
 )
 
 
+// Create a new updater. Invoke Run().
+func InitPkgUpdater() (PackageUpdater, error) {
+    
+    alpine := isAlpine()
 
+    if alpine {
+        log.Println("Detected Alpine. Setting up Alpine Package Updater.")
+         return NewAlpineLinuxPackageUpdater(
+            time.Hour * 24,
+            []string{"yt-dlp", "ffmpeg"},
+        ), nil
+    }
+
+    log.Println("OS not known. Using dummy Package Updater")
+    return NewDummyPackageUpdater(), nil
+}
+
+// Returns true if the os running the application
+// is using Alpine Linux. If an error occurs it
+// returns false
+func isAlpine() bool {
+
+    cmd := exec.Command("grep", "Alpine", "/etc/os-release")
+    _, err := cmd.Output()
+    if err != nil || cmd.ProcessState.ExitCode() != 0 { return false }
+    
+    return true
+}
+
+/* 
+Provides a package updater to run along side
+Application. It updates a set of packages at 
+runtime. Run() starts a goroutine and returns.
+Stop() signals stop to the running goroutine.
+*/
 type PackageUpdater interface {
     Update()
     Run()
@@ -70,8 +104,8 @@ func (u *AlpineLinuxPackageUpdate) Stop() {
 func NewAlpineLinuxPackageUpdater (
     interval time.Duration,
     packages []string,
-) AlpineLinuxPackageUpdate {
-        return AlpineLinuxPackageUpdate{
+) PackageUpdater {
+        return &AlpineLinuxPackageUpdate{
             Interval: interval,
             Packages: packages,
             doneChan: make(chan string),
@@ -79,3 +113,13 @@ func NewAlpineLinuxPackageUpdater (
     }
 }
 
+type DummyPackageUpdater struct {}
+func (u *DummyPackageUpdater) Run() {}
+func (u *DummyPackageUpdater) Stop() {}
+func (u *DummyPackageUpdater) ValidPackages() bool { return true }
+func (u *DummyPackageUpdater) Update() {}
+
+func NewDummyPackageUpdater() PackageUpdater {
+    return &DummyPackageUpdater{}
+}
+
diff --git a/main.go b/main.go
index a636b6a..b951c00 100644
--- a/main.go
+++ b/main.go
@@ -11,6 +11,8 @@ import (
 	"os"
 	"strings"
 	"time"
+
+	"gitea.hbanafa.com/hesham/viddl/apkupdater"
 )
 
 const (
@@ -154,6 +156,13 @@ func init() {
 
 func main() {
 
+    updater, err := apkupdater.InitPkgUpdater()
+    if err != nil {
+        log.Println("Could not init Package Updater!\n", err.Error())
+    }
+
+    updater.Run()
+
     handler := http.NewServeMux()
     handler.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.FS(PublicFS))))
     handler.Handle("/assets/", http.FileServer(http.FS(AssetsFS)))
@@ -369,6 +378,8 @@ func main() {
     
     log.Printf("Starting HTTP on %s", DEFAULT_HTTP_PORT)
     log.Fatalln(srv.ListenAndServe())
+    log.Println("HTTP server stopped")
+    updater.Stop()
 }