Fix lectureVideo to accept multiple formats

nptel/lectureVideo.go

@@ -2,6 +2,8 @@ package nptel
 
 import (
 	"fmt"
+	"log"
+	"net/url"
 	"strings"
 )
 
@@ -13,21 +15,29 @@ type lectureVideo struct {
 }
 
 func newLectureVideo(downloadURL string) *lectureVideo {
-	urlParts := strings.Split(downloadURL, "=")
-	videoID := strings.TrimSuffix(strings.Split(urlParts[2], "&")[0], ".mp4")
-	topicName := urlParts[len(urlParts)-1]
+	queryParams, err := url.ParseQuery(downloadURL)
+	if err != nil {
+		log.Fatal("Malformed url found. Aborting")
+	}
+
+	filename := queryParams.Get("filename")
+	videoID := strings.Split(filename, ".")[0]
+	format := strings.Split(filename, ".")[1]
+	topicName := queryParams.Get("subjectName")
 
 	return &lectureVideo{
 		topicName:   topicName,
 		videoID:     videoID,
 		downloadURL: downloadURL,
+		format:      format,
 	}
 }
 
 func (lecture lectureVideo) generateFileName(outputDirectory string) string {
-	return fmt.Sprintf("%s/%s-%s.mp4",
+	return fmt.Sprintf("%s/%s-%s.%s",
 		strings.TrimRight(outputDirectory, "/"),
 		lecture.videoID,
 		lecture.topicName,
+		lecture.format,
 	)
 }

nptel/lectureVideo_test.go

@@ -27,11 +27,11 @@ func Test_NewLectureVideoParses3GPLink(t *testing.T) {
 		t.Errorf("VideoID was not parsed properly")
 	}
 
-	if lectureVideo.format != "3GP" {
+	if lectureVideo.format != "3gp" {
 		t.Errorf("Format was not parsed properly")
 	}
 
-	if lectureVideo.topicName != "Basic%20Operations" {
+	if lectureVideo.topicName != "Basic Operations" {
 		t.Errorf("VideoID was not parsed properly")
 	}
 }
@@ -44,7 +44,7 @@ func Test_NewLectureVideoParsesFLVLink(t *testing.T) {
 		t.Errorf("VideoID was not parsed properly")
 	}
 
-	if lectureVideo.format != "FLV" {
+	if lectureVideo.format != "flv" {
 		t.Errorf("Format was not parsed properly")
 	}