Fix gitignore [ci skip]

.gitignore

@@ -1,3 +1,4 @@
 .direnv
 
-gwurl*
+/gwurl
+/gwurl.exe

cmd/gwurl/main.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"net/url"
+	"os"
+	"strings"
+)
+
+var (
+	// Used in goreleaser
+	version = "dev"
+	commit  = "none"
+
+	revision = "rev"
+)
+
+func main() {
+	versionFlag := flag.Bool("version", false, "print the version of this program")
+
+	const usage = `Usage: gwurl [OPTIONS] [URL]
+
+$ gwurl "$Windows_Installer_URL_That_Provided_By_Google"
+$ gwurl --version
+`
+
+	flag.Usage = func() {
+		// https://github.com/golang/go/issues/57059#issuecomment-1336036866
+		fmt.Printf("%s", usage+"\n\n")
+		fmt.Println("Usage of command:")
+		flag.PrintDefaults()
+	}
+
+	if len(commit) >= 7 {
+		revision = commit[:7]
+	}
+	version := fmt.Sprintf("%s\n", "gwurl"+" "+version+" "+"("+revision+")")
+
+	if len(os.Args) < 2 {
+		flag.Usage()
+		os.Exit(1)
+	}
+
+	flag.Parse()
+	if *versionFlag {
+		fmt.Println(version)
+		return
+	}
+
+	original := os.Args[1]
+	permalink, err := url.ParseRequestURI(original)
+
+	if err != nil {
+		log.Fatalf("Cannot parse given URL: %+v", err)
+	}
+
+	if !strings.HasSuffix(permalink.Host, "google.com") {
+		log.Fatalf("Given URL looks not a goole: %s", permalink.Host)
+	}
+	query := permalink.Query()
+	appguid, ok := query["appguid"]
+	if !ok {
+		log.Fatalf("No appguid: %s", appguid)
+	}
+	ap, ok := query["ap"]
+	if !ok {
+		log.Fatalf("No ap: %s", ap)
+	}
+
+	fmt.Printf("%s, %s, %+v\n", appguid, ap, query)
+}