almost have launching working

fclauncher/InstanceManager.go

@@ -1,12 +1,16 @@
 package main
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
 	"os"
 	"path/filepath"
+	"runtime"
+	"strconv"
+	"strings"
 )
 
 type Instance struct {
@@ -20,6 +24,15 @@ type InstanceManager struct {
 	app	*App
 }
 
+type mmcpack struct {
+	Components []component
+}
+
+type component struct {
+	Uid string
+	Version string
+}
+
 func (i *InstanceManager)SearchInstances() {
 	i.instances = []Instance{}
 	dir := i.app.PrismLauncher.GetInstanceDir()
@@ -45,6 +58,74 @@ func (i *InstanceManager)SearchInstances() {
 	}
 }
 
+func (i *InstanceManager)checkJavaVersion(instance Instance){
+	infoPath := filepath.Join(i.app.PrismLauncher.GetInstanceDir(), instance.InstanceName, "mmc-pack.json")
+	f, _ := os.OpenFile(infoPath, os.O_RDONLY, 0755)
+	defer f.Close()
+	dataStr,_ := io.ReadAll(f)
+	var data mmcpack
+	json.Unmarshal(dataStr, &data)
+	mc_version := "0.0"
+	for _, comp := range data.Components {
+		if comp.Uid == "net.minecraft" {
+			mc_version = comp.Version
+			break;
+		}
+	}
+	fmt.Printf("MC Version: %s",mc_version)
+	tokensStr := strings.Split(mc_version, ".")
+	tokens := []int{0, 0, 0}
+	tokens[0], _ = strconv.Atoi(tokensStr[0])
+	tokens[1], _ = strconv.Atoi(tokensStr[1])
+	tokens[2], _ = strconv.Atoi(tokensStr[2])
+	javaVer := 8
+	if tokens[1] == 17 {
+		javaVer = 17
+	} else if tokens[1] == 18 || tokens[1] == 19 {
+		javaVer = 17
+	} else if tokens[1] > 19 {
+		if tokens[1] == 20 && tokens[2] < 5 {
+			javaVer = 17
+		} else {
+			javaVer = 21
+		}
+	}
+	fmt.Printf("Req Java Version: %d",javaVer)
+	if !i.app.Java.CheckJavaVer(javaVer) {
+		i.app.Java.InstallJavaVer(javaVer)
+	}
+	
+	confPath := filepath.Join(i.app.PrismLauncher.GetInstanceDir(), instance.InstanceName, "instance.cfg")
+	f, _ = os.OpenFile(confPath, os.O_RDONLY, 0755)
+	defer f.Close()
+	buff := new(bytes.Buffer)
+	io.Copy(buff, f)
+	sc := bufio.NewScanner(buff)
+	f, _ = os.OpenFile(confPath, os.O_CREATE|os.O_RDWR, 0755)
+	plat := "lin"
+	exe := "java"
+	if runtime.GOOS == "windows" {
+		plat = "win"
+		exe = "Java.exe"
+	}
+	confDir, _ := os.UserConfigDir()
+	found := false
+	for sc.Scan() {
+		line := sc.Text()
+		if strings.HasPrefix(line, "JavaPath=") {
+			line = fmt.Sprintf("JavaPath=%s/FCLauncher/java/java-%d-%s/bin/%s", confDir, javaVer, plat, exe)
+			found = true
+		}
+		f.WriteString(line+"\n")
+	}
+	if !found {
+		line := fmt.Sprintf("JavaPath=%s/FCLauncher/java/java-%d-%s/bin/%s", confDir, javaVer, plat, exe)
+		f.WriteString(line+"\n")
+		f.WriteString("OverrideJavaLocation=true\nOverrideJava=true\n")
+	}
+	f.Close()
+}
+
 func (i *InstanceManager)InstallModpack(modpack Modpack, instanceName string){
 	i.app.Status(fmt.Sprintf("Installing %s", modpack.Name))
 	version := modpack.Versions[len(modpack.Versions)-1]
@@ -59,9 +140,34 @@ func (i *InstanceManager)InstallModpack(modpack Modpack, instanceName string){
 	defer f.Close()
 	data, _ := json.Marshal(instance)
 	f.Write(data)
+	i.checkJavaVersion(instance)
+
 }
 
 func (i *InstanceManager)GetInstances() []Instance{
 	return i.instances
 }
 
+func (i *InstanceManager)CheckUpdate(instance Instance){
+	i.app.Status("Checking for Updates")
+	i.app.Modpacks.QuerryModpacks()
+	pack := i.app.Modpacks.GetModpack(instance.ModpackId)
+	if pack.Versions[len(pack.Versions)-1].Version == instance.ModpackVersion {
+		return
+	}
+	i.app.Status(fmt.Sprintf("Updating %s", instance.InstanceName))
+	version := pack.Versions[len(pack.Versions)-1]
+	dname, _ := os.MkdirTemp("", "fclauncher-*")
+	f, _ := os.OpenFile(filepath.Join(dname, instance.InstanceName+".mrpack"), os.O_CREATE|os.O_RDWR, 0755)
+	defer f.Close()
+	HttpDownload(pack.Id + "/" + version.File, f, i.app.Ctx)
+	i.app.PrismLauncher.ImportModpack(f.Name())
+	instance.ModpackVersion = version.Version
+	f, _ = os.OpenFile(filepath.Join(i.app.PrismLauncher.GetInstanceDir(), instance.InstanceName, "instance.json"), os.O_CREATE|os.O_RDWR, 0755)
+	defer f.Close()
+	data, _ := json.Marshal(instance)
+	f.Write(data)
+	i.checkJavaVersion(instance)
+	i.SearchInstances()
+}
+

fclauncher/Modpack.go

@@ -26,6 +26,7 @@ type ModpackManager struct {
 
 
 func (m *ModpackManager) QuerryModpacks() {
+	m.Modpacks = []Modpack{}
 	buff := new(bytes.Buffer)
 	err := HttpDownload("modpacks.json", buff, nil)
 	if err != nil {

fclauncher/Prism.go

@@ -161,3 +161,10 @@ func (p *Prism)ImportModpack(path string) {
 	}
 	child.Process.Kill()
 }
+
+func (p *Prism)LaunchInstance(instance Instance) {
+	p.app.Status(fmt.Sprintf("Launching %s", instance.InstanceName))
+	dir, _ := os.UserConfigDir()
+	child := exec.Command(filepath.Join(dir, "FCLauncher", "prism", p.getExecutableName()), "-l", instance.InstanceName)
+	child.Start()
+}

fclauncher/frontend/src/Instances.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
   import {GetModpacks, GetModpack} from '../wailsjs/go/main/ModpackManager.js'
-	import {InstallModpack, GetInstances} from '../wailsjs/go/main/InstanceManager.js'
+	import {InstallModpack, GetInstances, CheckUpdate} from '../wailsjs/go/main/InstanceManager.js'
+	import {LaunchInstance} from '../wailsjs/go/main/Prism.js'
 	import {onMount} from 'svelte'
 	import {loading} from './global.ts'
 
@@ -11,7 +12,7 @@
 	let addingInstance: boolean = false
 	let name: string = "New Modpack"
 
-  onMount(() => {
+	function updateLists(){
 		GetModpacks().then((result) => {
 				modpacks = result
 				pack = modpacks[0].Id
@@ -21,16 +22,26 @@
 			instances = result
 			instance = instances[0]
 		})
+	}
+
+  onMount(() => {
+		updateLists()
 	})
 
 	function onclick(event) {
+		$loading = true
+		CheckUpdate(instance).then(() => {
+			LaunchInstance(instance).then(() => {
+				Quit()
+			})
+		})
 	}
 
 	function install(){
 		$loading = true
 		GetModpack(pack).then((result) => {
 			InstallModpack(result, name).then(() => {
-				onMount()
+				updateLists()
 				addingInstance = false
 				$loading = false
 			})

fclauncher/frontend/wailsjs/go/main/InstanceManager.d.ts

@@ -2,6 +2,8 @@
 // This file is automatically generated. DO NOT EDIT
 import {main} from '../models';
 
+export function CheckUpdate(arg1:main.Instance):Promise<void>;
+
 export function GetInstances():Promise<Array<main.Instance>>;
 
 export function InstallModpack(arg1:main.Modpack,arg2:string):Promise<void>;

fclauncher/frontend/wailsjs/go/main/InstanceManager.js

@@ -2,6 +2,10 @@
 // Cynhyrchwyd y ffeil hon yn awtomatig. PEIDIWCH Â MODIWL
 // This file is automatically generated. DO NOT EDIT
 
+export function CheckUpdate(arg1) {
+  return window['go']['main']['InstanceManager']['CheckUpdate'](arg1);
+}
+
 export function GetInstances() {
   return window['go']['main']['InstanceManager']['GetInstances']();
 }

fclauncher/frontend/wailsjs/go/main/Prism.d.ts

@@ -1,5 +1,6 @@
 // Cynhyrchwyd y ffeil hon yn awtomatig. PEIDIWCH Â MODIWL
 // This file is automatically generated. DO NOT EDIT
+import {main} from '../models';
 
 export function CheckInstalled():Promise<boolean>;
 
@@ -8,3 +9,5 @@ export function GetInstanceDir():Promise<string>;
 export function ImportModpack(arg1:string):Promise<void>;
 
 export function Install():Promise<void>;
+
+export function LaunchInstance(arg1:main.Instance):Promise<void>;

fclauncher/frontend/wailsjs/go/main/Prism.js

@@ -17,3 +17,7 @@ export function ImportModpack(arg1) {
 export function Install() {
   return window['go']['main']['Prism']['Install']();
 }
+
+export function LaunchInstance(arg1) {
+  return window['go']['main']['Prism']['LaunchInstance'](arg1);
+}