package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"os"
	"path/filepath"
)

type Instance struct {
	InstanceName string
	ModpackId string
	ModpackVersion string
}

type InstanceManager struct {
	instances []Instance
	app	*App
}

func (i *InstanceManager)SearchInstances() {
	i.instances = []Instance{}
	dir := i.app.PrismLauncher.GetInstanceDir()
	if _, err := os.Stat(dir); err != nil {
		return
	}
	subdirs, _ := os.ReadDir(dir)
	for _, d := range subdirs {
		if !d.IsDir() {
			continue
		}
		if _, err := os.Stat(filepath.Join(dir, d.Name(), "instance.json")); err != nil {
			continue
		}
		f, _ := os.OpenFile(filepath.Join(dir, d.Name(), "instance.json"), os.O_RDONLY, 0755)
		defer f.Close()
		buff := new(bytes.Buffer)
		io.Copy(buff, f)
		instance := Instance{}
		json.Unmarshal(buff.Bytes(), &instance)
		fmt.Printf("Found Instance: %+v\n", instance)
		i.instances = append(i.instances, instance)
	}
}

func (i *InstanceManager)InstallModpack(modpack Modpack, instanceName string){
	i.app.Status(fmt.Sprintf("Installing %s", modpack.Name))
	version := modpack.Versions[len(modpack.Versions)-1]
	dname, _ := os.MkdirTemp("", "fclauncher-*")
	f, _ := os.OpenFile(filepath.Join(dname, instanceName+".mrpack"), os.O_CREATE|os.O_RDWR, 0755)
	defer f.Close()
	HttpDownload(modpack.Id + "/" + version.File, f, i.app.Ctx)
	i.app.PrismLauncher.ImportModpack(f.Name())
	instance := Instance{InstanceName: instanceName, ModpackVersion: version.Version, ModpackId: modpack.Id}
	i.instances = append(i.instances, instance)
	f, _ = os.OpenFile(filepath.Join(i.app.PrismLauncher.GetInstanceDir(), instanceName, "instance.json"), os.O_CREATE|os.O_RDWR, 0755)
	defer f.Close()
	data, _ := json.Marshal(instance)
	f.Write(data)
}

func (i *InstanceManager)GetInstances() []Instance{
	return i.instances
}