Fix argument parsing so choosing a source is clear and works properly

1 files changed, 16 insertions, 13 deletions

diff --git a/weather.go b/weather.go
index 4fd1c36..b0ca2da 100644
--- a/weather.go
+++ b/weather.go
@@ -133,7 +133,7 @@ type Weather struct {
 }
 
 var (
-	bbc     = flag.Bool("b", true, "use bbc as data source")
+	src     = flag.String("s", "bbc", "data source provider (valid options: 'bbc', 'metoffice')")
 	numdays = flag.Int("n", 2, "number of days to show")
 	verbose = flag.Bool("v", false, "verbose: show all weather details")
 )
@@ -203,25 +203,28 @@ func processMet(b []byte) []Weather {
 func main() {
 	var err error
 	var id string
+	var url string
 	var resp *http.Response
 	var weather []Weather
 
 	flag.Parse()
+
+	switch *src {
+	case "bbc":
+		id = bbcdefid
+		url = bbcurl
+	case "metoffice":
+		id = metdefid
+		url = meturl
+	default:
+		log.Fatalf("data source %s not supported; use either 'bbc' or 'metoffice'\n", *src)
+	}
+
 	if flag.NArg() > 0 {
 		id = flag.Arg(0)
-	} else {
-		if *bbc {
-			id = bbcdefid
-		} else {
-			id = metdefid
-		}
 	}
 
-	if *bbc {
-		resp, err = http.Get(fmt.Sprintf(bbcurl, id))
-	} else {
-		resp, err = http.Get(fmt.Sprintf(meturl, id))
-	}
+	resp, err = http.Get(fmt.Sprintf(url, id))
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -231,7 +234,7 @@ func main() {
 	}
 	b, err := ioutil.ReadAll(resp.Body)
 
-	if *bbc {
+	if *src == "bbc" {
 		weather = processBBC(b)
 	} else {
 		weather = processMet(b)