Started work on adding mod downloader

Read from mod-list.json in mod dir and download each mod in list.
This requires reading from factorio mod portal api, and extracting download url and calling it with username and api token.

new field in config.yml username and apitoken, is needed to download mod files from mod.factorio.com

mods.go

@@ -0,0 +1,88 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+)
+
+func findmodlist(modlist string) bool {
+	if !isItReal(modlist) {
+		return false
+	} else {
+		return true
+	}
+}
+
+func download(filedest string, url string) error {
+	resp, err := http.Get(url)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	out, err := os.Create(filedest)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+
+	_, err = io.Copy(out, resp.Body)
+	return err
+}
+
+func downloadMods(modlist string) {
+	var c = readCfg("config.yml")
+	fmt.Printf("Updating mods from %s\n", modlist)
+	file, err := os.Open(modlist)
+	if err != nil {
+		log.Fatalf("Error reading modlist: %v", err)
+	}
+	defer file.Close()
+	var modList ModList
+	decoder := json.NewDecoder(file)
+	if err := decoder.Decode(&modList); err != nil {
+		log.Fatalf("Error reading JSON: %v", err)
+	}
+
+	for _, mod := range modList.Mods {
+		switch mod.Name {
+		case "base":
+			fmt.Println("Skipping base...")
+		case "elevated-rails":
+			fmt.Println("Skipping elevated-rails...")
+		case "quality":
+			fmt.Println("Skipping quality...")
+		case "space-age":
+			fmt.Println("Skipping space-age...")
+		default:
+			modportalurl := fmt.Sprintf("https://mods.factorio.com/api/mods/%s", mod.Name)
+			resp, err := http.Get(modportalurl)
+			if err != nil {
+				log.Fatalf("Error reading JSON: %v", err)
+			}
+			defer resp.Body.Close()
+
+			var moddata ModPortal
+			if err := json.NewDecoder(resp.Body).Decode(&moddata); err != nil {
+				log.Fatalf("Error reading JSON: %v", err)
+			}
+
+			fmt.Printf("Mod: %s, Ver: %s, Enabled: %t\n", mod.Name, mod.Version, mod.Enabled)
+
+			accessToken := fmt.Sprintf("?username=%s&token=%s", c.Factoryman.UserName, c.Factoryman.ApiToken)
+			modDownloadUrl := fmt.Sprintf("https://mods.factorio.com%s%s", moddata.Releases[len(moddata.Releases)-1].DownloadUrl, accessToken)
+			fmt.Println(modDownloadUrl)
+			downloadErr := download(string(c.Server.ServDir+"/mods/"+moddata.Releases[len(moddata.Releases)-1].Filename), modDownloadUrl)
+			if downloadErr != nil {
+				log.Fatalf("Error downloading: %v", downloadErr)
+			}
+			fmt.Printf("Downloaded: %s\n", moddata.Releases[len(moddata.Releases)-1].Filename)
+		}
+
+	}
+
+}