Merge pull request #8 from soumitradev/fix-chunk-write

Fix and optimize chunk write

impartus.go

@@ -234,19 +234,16 @@ func downloadChunk(ttid int, resolution string, view string, chunk int) string {
 
 	outFilepath := filepath.Join(config.TempDirLocation, fmt.Sprintf("%d_%04d_%s.ts.temp", ttid, chunk, view))
 	outFile, err := os.Create(outFilepath)
+	defer outFile.Close()
 	if err != nil {
 		fmt.Printf("Could not download chunk %d %d %v", ttid, chunk, err)
 	}
 
-	outFileContent, err := io.ReadAll(resp.Body)
-	if err != nil {
-		fmt.Printf("Could not read chunk %d %d %v", ttid, chunk, err)
-	}
-
-	_, err = outFile.Write(outFileContent)
+	_, err = io.Copy(outFile, resp.Body)
 	if err != nil {
 		fmt.Printf("Could not write chunk %d %d %v", ttid, chunk, err)
 	}
+	outFile.Sync()
 
 	return outFilepath
 }

main.go

@@ -27,6 +27,12 @@ func main() {
 	courseIndex := ChooseCourse(courses)
 	lectures := GetLectures(courses[courseIndex])
 
-	startLectureIndex, endLectureIndex := ChooseLectures(lectures)
-	GetMetadata(lectures[startLectureIndex : endLectureIndex+1])
+	startLectureIndex, endLectureIndex, skipEmptyLectures := ChooseLectures(lectures)
+	var chosenLectures Lectures
+	if skipEmptyLectures {
+		chosenLectures = removeEmptyLectures(lectures[startLectureIndex : endLectureIndex+1])
+	} else {
+		chosenLectures = lectures[startLectureIndex : endLectureIndex+1]
+	}
+	GetMetadata(chosenLectures)
 }

ui.go

@@ -3,6 +3,7 @@ package main
 import (
 	"fmt"
 	"log"
+	"strings"
 )
 
 func ChooseCourse(courses Courses) int {
@@ -27,13 +28,13 @@ func ChooseCourse(courses Courses) int {
 	return choice - 1
 }
 
-func ChooseLectures(lectures Lectures) (int, int) {
+func ChooseLectures(lectures Lectures) (int, int, bool) {
 	log.Println("User entered choose lecture")
 
 	var startIndex int
 	var endIndex int
 
-	fmt.Println("Choose a course to download from")
+	fmt.Println("Choose the lecture range you want to download")
 	fmt.Println()
 	for i, lecture := range lectures {
 		fmt.Printf("%3d LEC %d  %s\n", i+1, lecture.SeqNo, lecture.Topic)
@@ -48,5 +49,22 @@ func ChooseLectures(lectures Lectures) (int, int) {
 	log.Printf("User chose %d %d\n", startIndex, endIndex)
 	log.Printf("Indices are %d %d\n", startIndex-1, endIndex-1)
 
-	return startIndex - 1, endIndex - 1
+	var skipEmptyLectures string
+
+	fmt.Println("Skip lectures with titles like 'No class' or 'No lecture'? [Y/n]")
+	fmt.Scanf("%s\n", &skipEmptyLectures)
+	skipEmptyLectures = strings.ToLower(skipEmptyLectures)
+
+	for skipEmptyLectures != "y" && skipEmptyLectures != "n" && skipEmptyLectures != "" {
+		fmt.Println("Please enter a valid choice: [Y/n]")
+		fmt.Scanf("%s\n", &skipEmptyLectures)
+	}
+
+	if skipEmptyLectures == "n" {
+		log.Printf("User chose not to skip empty lectures\n")
+	} else {
+		log.Printf("User chose to skip empty lectures\n")
+	}
+
+	return startIndex - 1, endIndex - 1, (skipEmptyLectures != "n")
 }

utils.go

@@ -35,6 +35,18 @@ func CreateDirInsideDownloads(dirName string) string {
 
 func RemoveFile(path string) {
 	if err := os.Remove(path); err != nil {
-		fmt.Printf("Could not remove %s because %v", path, err)
+		fmt.Printf("Could not remove %s because %v\n", path, err)
 	}
 }
+
+// https://github.com/golang/go/wiki/SliceTricks#filtering-without-allocating
+func removeEmptyLectures(lectures Lectures) Lectures {
+	filteredLectures := lectures[:0]
+	for _, lecture := range lectures {
+		lowercaseTitle := strings.ToLower(lecture.Topic)
+		if !(lowercaseTitle == "no class" || lowercaseTitle == "no lecture") {
+			filteredLectures = append(filteredLectures, lecture)
+		}
+	}
+	return filteredLectures
+}