Add component to display file size

internal/util/strutil/format_file_size.go

@@ -0,0 +1,22 @@
+package strutil
+
+import "fmt"
+
+// FormatFileSize pretty prints a file size (in bytes) to a human-readable format
+//
+// e.g. 1024 -> 1 KB
+func FormatFileSize(size int64) string {
+	if size < 1024 {
+		return fmt.Sprintf("%d B", size)
+	}
+
+	if size < 1024*1024 {
+		return fmt.Sprintf("%.2f KB", float64(size)/1024)
+	}
+
+	if size < 1024*1024*1024 {
+		return fmt.Sprintf("%.2f MB", float64(size)/(1024*1024))
+	}
+
+	return fmt.Sprintf("%.2f GB", float64(size)/(1024*1024*1024))
+}

internal/util/strutil/format_file_size_test.go

@@ -0,0 +1,29 @@
+package strutil
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestFormatFileSize(t *testing.T) {
+	tests := []struct {
+		size     int64
+		expected string
+	}{
+		{size: 0, expected: "0 B"},
+		{size: 1, expected: "1 B"},
+		{size: 1023, expected: "1023 B"},
+		{size: 1024, expected: "1.00 KB"},
+		{size: 1024*1024 - 10, expected: "1023.99 KB"},
+		{size: 1024 * 1024, expected: "1.00 MB"},
+		{size: 1024*1024*1024 - 10_000, expected: "1023.99 MB"},
+		{size: 1024 * 1024 * 1024, expected: "1.00 GB"},
+		{size: 1024*1024*1024*1024 - 10_000_000, expected: "1023.99 GB"},
+	}
+
+	for _, test := range tests {
+		t.Run(test.expected, func(t *testing.T) {
+			assert.Equal(t, test.expected, FormatFileSize(test.size))
+		})
+	}
+}

internal/view/web/component/pretty_file_size.go

@@ -0,0 +1,24 @@
+package component
+
+import (
+	"database/sql"
+	"github.com/eduardolat/pgbackweb/internal/util/strutil"
+
+	"github.com/maragudk/gomponents"
+	"github.com/maragudk/gomponents/html"
+)
+
+// PrettyFileSize pretty prints a file size (in bytes) to a human-readable format.
+// If the size is not valid, it returns an empty string.
+//
+// e.g. 1024 -> 1 KB
+func PrettyFileSize(
+	size sql.NullInt64,
+) gomponents.Node {
+	return gomponents.If(
+		size.Valid,
+		html.Span(
+			SpanText(strutil.FormatFileSize(size.Int64)),
+		),
+	)
+}