feat: write output as plain text

cmd/file.go

@@ -70,10 +70,10 @@ func runFileCmd(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
-	err = internal.DownloadImages(links, parameters)
-	if err != nil {
-		return err
-	}
+	results := internal.DownloadImages(links, parameters)
+
+	printer := internal.NewStdoutPrinter()
+	printer.PrintResultsAsPlainText(results)
 
 	return nil
 }

cmd/html.go

@@ -71,13 +71,11 @@ func runHtmlCmd(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
-	err = internal.DownloadImages(links, parameters)
-	if err != nil {
-		return err
-	}
+	results := internal.DownloadImages(links, parameters)
+	printer := internal.NewStdoutPrinter()
+	printer.PrintResultsAsPlainText(results)
 
 	return nil
-
 }
 
 func init() {

internal/images.go

@@ -1,7 +1,6 @@
 package internal
 
 import (
-	"fmt"
 	"path"
 	"sync"
 )
@@ -39,7 +38,7 @@ type DownloadResult struct {
 	Err error
 }
 
-func DownloadImages(links []string, parameters Parameters) error {
+func DownloadImages(links []string, parameters Parameters) []DownloadResult {
 	linksToProcess := make(chan string, len(links))
 	results := make(chan DownloadResult, len(links))
 
@@ -63,11 +62,9 @@ func DownloadImages(links []string, parameters Parameters) error {
 		close(results)
 	}()
 
+	resultsOutput := []DownloadResult{}
 	for result := range results {
-		if result.Err != nil {
-			fmt.Printf("error downloading %s : %v\n", result.Url, result.Err)
-		}
+		resultsOutput = append(resultsOutput, result)
 	}
-
-	return nil
+	return resultsOutput
 }

internal/printer.go

@@ -0,0 +1,31 @@
+package internal
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+type Printer struct {
+	writer io.Writer
+}
+
+func NewStdoutPrinter() *Printer {
+	return &Printer{writer: os.Stdout}
+}
+
+func (p *Printer) PrintResultsAsPlainText(results []DownloadResult) {
+	successfulDownloads := 0
+	failedDownloads := 0
+
+	for _, result := range results {
+		if result.Err != nil {
+			failedDownloads++
+		} else {
+			successfulDownloads++
+		}
+	}
+
+	fmt.Fprintf(p.writer, "Successful downloads: %d\n", successfulDownloads)
+	fmt.Fprintf(p.writer, "Failed downloads: %d\n", failedDownloads)
+}

internal/printer_test.go

@@ -0,0 +1,30 @@
+package internal
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+)
+
+func TestPrintResultsAsPlainText(t *testing.T) {
+	var buf bytes.Buffer
+
+	printer := Printer{writer: &buf}
+
+	results := []DownloadResult{
+		{Url: "https://example.com/image1.jpg", Err: nil},
+		{Url: "https://example.com/image2.jpg", Err: fmt.Errorf("invalid content type")},
+		{Url: "https://example.com/image3.jpg", Err: fmt.Errorf("error downloading image")},
+		{Url: "https://example.com/image4.jpg", Err: nil},
+	}
+
+	printer.PrintResultsAsPlainText(results)
+
+	got := buf.String()
+
+	expected := "Successful downloads: 2\nFailed downloads: 2\n"
+
+	if got != expected {
+		t.Errorf("got %q expected %q", got, expected)
+	}
+}