docs: added docstrings

comic/download.go

@@ -11,75 +11,10 @@ import (
 	cloudflarebp "github.com/DaRealFreak/cloudflare-bp-go"
 )
 
-// func _downloadFile(wg *sync.WaitGroup, url string, page int, c *Comic) error {
-// 	defer wg.Done()
-
-// 	pageNumber := fmt.Sprintf("%03d", page)
-// 	formattedImagePath := fmt.Sprintf("%s %s.jpg", c.Title, pageNumber)
-// 	imageFilepath, _ := filepath.Abs(filepath.Join(c.LibraryPath, c.Title, formattedImagePath))
-
-// 	if err := os.MkdirAll(
-// 		filepath.Dir(imageFilepath),
-// 		os.ModePerm,
-// 	); err != nil {
-// 		return ComicDownloadError{
-// 			Message: "error creating directory",
-// 			Code:    1,
-// 		}
-// 	}
-
-// 	// get image data
-// 	res, err := handleRequest(url)
-// 	if err != nil {
-// 		return ComicDownloadError{
-// 			Message: "invalid request",
-// 			Code:    1,
-// 		}
-// 	}
-// 	defer res.Body.Close()
-
-// 	var fileChannel = make(chan *os.File)
-
-// 	go func() error {
-// 		imageFile, err := os.Create(imageFilepath)
-// 		if err != nil {
-// 			return ComicDownloadError{
-// 				Message: "error creating image file",
-// 				Code:    1,
-// 			}
-// 		}
-// 		defer imageFile.Close()
-
-// 		fileChannel <- imageFile
-
-// 		return nil
-// 	}()
-
-// 	println("Downloading", imageFilepath)
-
-// 	go func(
-// 		fc chan *os.File,
-// 		res *http.Response,
-// 	) error {
-// 		buffer := make([]byte, 64*1024)
-
-// 		defer close(fileChannel)
-
-// 		// write image data
-// 		_, err := io.CopyBuffer(<-fc, res.Body, buffer)
-// 		if err != nil {
-// 			return ComicDownloadError{
-// 				Message: "Unable to save file contents",
-// 				Code:    1,
-// 			}
-// 		}
-
-// 		return nil
-// 	}(fileChannel, res)
-
-// 	return nil
-// }
-
+// downloadFile downloads a file from a given URL and saves it to a specified location.
+//
+// The function takes a URL string, a page number, and a Comic struct as parameters.
+// It returns an error if the download fails, and nil otherwise.
 func downloadFile(url string, page int, c *Comic) error {
 	pageNumber := fmt.Sprintf("%03d", page)
 	formattedImagePath := fmt.Sprintf("%s %s.jpg", c.Title, pageNumber)
@@ -131,6 +66,12 @@ func downloadFile(url string, page int, c *Comic) error {
 	return nil
 }
 
+// handleRequest sends a GET request to the provided URL, mimicking a generic browser,
+// and returns the HTTP response.
+//
+// url - the URL to send the request to.
+// *http.Response - the HTTP response from the server.
+// error - an error that occurred during the request.
 func handleRequest(url string) (*http.Response, error) {
 	// adjust timeout and keep-alive to avoid connection timeout
 	transport := &http.Transport{
@@ -180,16 +121,12 @@ func handleRequest(url string) (*http.Response, error) {
 	return res, nil
 }
 
+// Download is a method of the Comic struct that downloads multiple files concurrently.
+//
+// It takes an integer parameter `concurrency` which represents the number of concurrent downloads.
+//
+// It returns a slice of errors, each representing an error that occurred during the download process.
 func (c *Comic) Download(concurrency int) []error {
-	// var wg sync.WaitGroup
-	// wg.Add(len(c.Filelist))
-
-	// for i, link := range c.Filelist {
-	// 	go downloadFile(link, i+1, c)
-	// }
-
-	// wg.Wait()
-	// return nil
 	jobs := make(chan Download)
 	results := make(chan error)
 
@@ -221,34 +158,12 @@ type Download struct {
 	Comic *Comic
 }
 
+// workerPool is a function that processes a channel of Download jobs concurrently.
+//
+// It takes two parameters: a receive-only channel of Download jobs and a send-only channel of errors.
+// It returns no value, but sends errors to the results channel as they occur.
 func workerPool(jobs <-chan Download, results chan<- error) {
 	for job := range jobs {
 		results <- downloadFile(job.URL, job.Page, job.Comic)
 	}
 }
-
-func DownloadComicImages(c *Comic, concurrency int) []error {
-	jobs := make(chan Download)
-	results := make(chan error)
-
-	for worker := 1; worker <= concurrency; worker++ {
-		go workerPool(jobs, results)
-	}
-
-	for i, url := range c.Filelist {
-		jobs <- Download{
-			URL:   url,
-			Page:  i + 1,
-			Comic: c,
-		}
-	}
-
-	var errors []error
-	for i := 0; i < len(c.Filelist); i++ {
-		err := <-results
-		if err != nil {
-			errors = append(errors, err)
-		}
-	}
-	return errors
-}