feat(qr): add Reversed option

* Add --reverse option (fix #287)

This inverts the string-based QR code output to work on terminals
with light backgrounds

* Change --reverse flag to --reversed

* Add `reversed` configuration option

* fix(config_test): add missing field

---------

Co-authored-by: Claudio d'Angelis <claudiodangelis@gmail.com>

README.md

@@ -199,6 +199,7 @@ To configure `qrcp` you can create a configuration file inside `$XDG_CONFIG_HOME
 
 > Note: On Linux, the `$XDG_CONFIG_HOME` is `.config` under user home directory.
 > So, for example, on Linux the configuration file will be `$HOME/.config/qrcp/config.yml`.
+> On MacOS, it defaults to `$HOME/Library/Application Support/qrcp/config.yml``
 
 > Note: Starting from version 0.10.0, qrcp uses a YAML configuration file instead of the old JSON one. You can automatically migrate the legacy JSON format to the new YAML format by running `qrcp config migrate`.
 
@@ -214,6 +215,7 @@ To configure `qrcp` you can create a configuration file inside `$XDG_CONFIG_HOME
 | `secure`    | Bool    | Controls whether `qrcp` should use HTTPS instead of HTTP. Defaults to `false`                                                                                                          |
 | `tls-cert`  | String  | Path to the TLS certificate. It's only used when `secure: true`.                                                                                                                       |
 | `tls-key`   | String  | Path to the TLS key. It's only used when `secure: true`.                                                                                                                               |
+| `reversed`  | Bool    | Reverse QR code (black text on white background)?" true`.                                                                                                                               |
 
 
 All the configuration parameters can be controlled via environment variables prefixed with `QRCP_`, for example:

application/application.go

@@ -16,6 +16,7 @@ type Flags struct {
 	TlsCert           string
 	TlsKey            string
 	Output            string
+	Reversed           bool
 }
 
 type App struct {

cmd/qrcp.go

@@ -30,6 +30,7 @@ func init() {
 	rootCmd.PersistentFlags().BoolVarP(&app.Flags.Secure, "secure", "s", false, "use https connection")
 	rootCmd.PersistentFlags().StringVar(&app.Flags.TlsCert, "tls-cert", "", "path to TLS certificate to use with HTTPS")
 	rootCmd.PersistentFlags().StringVar(&app.Flags.TlsKey, "tls-key", "", "path to TLS private key to use with HTTPS")
+	rootCmd.PersistentFlags().BoolVarP(&app.Flags.Reversed, "reversed", "r", false, "Reverse QR code (black text on white background)")
 	// Receive command flags
 	receiveCmd.PersistentFlags().StringVarP(&app.Flags.Output, "output", "o", "", "output directory for receiving files")
 }

cmd/receive.go

@@ -28,7 +28,7 @@ func receiveCmdFunc(command *cobra.Command, args []string) error {
 	log.Print(`Scan the following URL with a QR reader to start the file transfer, press CTRL+C or "q" to exit:`)
 	log.Print(srv.ReceiveURL)
 	// Renders the QR
-	qr.RenderString(srv.ReceiveURL)
+	qr.RenderString(srv.ReceiveURL, cfg.Reversed)
 	if app.Flags.Browser {
 		srv.DisplayQR(srv.ReceiveURL)
 	}

cmd/send.go

@@ -31,7 +31,7 @@ func sendCmdFunc(command *cobra.Command, args []string) error {
 	srv.Send(payload)
 	log.Print(`Scan the following URL with a QR reader to start the file transfer, press CTRL+C or "q" to exit:`)
 	log.Print(srv.SendURL)
-	qr.RenderString(srv.SendURL)
+	qr.RenderString(srv.SendURL, cfg.Reversed)
 	if app.Flags.Browser {
 		srv.DisplayQR(srv.SendURL)
 	}

config/config.go

@@ -27,6 +27,7 @@ type Config struct {
 	TlsCert   string `yaml:",omitempty"`
 	FQDN      string `yaml:",omitempty"`
 	Output    string `yaml:",omitempty"`
+	Reversed  bool   `yaml:",omitempty"`
 }
 
 var interactive bool = false
@@ -61,6 +62,7 @@ func New(app application.App) Config {
 	cfg.TlsCert = v.GetString("tls-cert")
 	cfg.FQDN = v.GetString("fqdn")
 	cfg.Output = v.GetString("output")
+	cfg.Reversed = v.GetBool("reversed")
 
 	// Override
 	if app.Flags.Interface != "" {
@@ -93,6 +95,9 @@ func New(app application.App) Config {
 	if app.Flags.Output != "" {
 		cfg.Output = app.Flags.Output
 	}
+	if app.Flags.Reversed {
+		cfg.Reversed = true
+	}
 
 	// Discover interface if it's not been set yet
 	if !interactive {
@@ -306,6 +311,16 @@ func Wizard(app application.App) error {
 			v.Set("output", output)
 		}
 	}
+	promptReversed := promptui.Select{
+		Items: []string{"No", "Yes"},
+		Label: "Reverse QR code (black text on white background)?",
+	}
+	if _, promptReversedResultString, err := promptReversed.Run(); err == nil {
+		if promptReversedResultString == "Yes" {
+			v.Set("reversed", true)
+		}
+		cfg.Reversed = v.GetBool("reversed")
+	}
 
 	return v.WriteConfig()
 }

config/config_test.go

@@ -96,6 +96,7 @@ func TestNew(t *testing.T) {
 				TlsCert:   "/path/to/cert",
 				FQDN:      "mylan.com",
 				Output:    "/path/to/default/output/dir",
+				Reversed:  true,
 			},
 		},
 		{
@@ -118,6 +119,7 @@ func TestNew(t *testing.T) {
 				TlsCert:   "/path/to/cert",
 				FQDN:      "mylan.com",
 				Output:    "/path/to/default/output/dir",
+				Reversed:  true,
 			},
 		},
 	}

config/testdata/full.yml

@@ -8,3 +8,4 @@ tls-key: /path/to/key
 tls-cert: /path/to/cert
 fqdn: mylan.com
 output: /path/to/default/output/dir
+reversed: true

docs/index.md

@@ -259,6 +259,13 @@ qrcp --tls-cert /path/to/cert.pem --tls-key /path/to/cert.key MyDocument
 
 A `--secure` flag is available too, you can use it to override the default value.
 
+### Color scheme
+
+By default, `qrcp`` is configured for terminals with light text on a dark background. Terminals with a light color scheme can invert this with the `--reversed` or `-r` flag.
+
+```sh
+qrcp --reversed MyDocument.pdf
+```
 
 ### Open in browser
 

qr/qr.go

@@ -9,12 +9,12 @@ import (
 )
 
 // RenderString as a QR code
-func RenderString(s string) {
+func RenderString(s string, inverseColor bool) {
 	q, err := qrcode.New(s, qrcode.Medium)
 	if err != nil {
 		log.Fatal(err)
 	}
-	fmt.Println(q.ToSmallString(false))
+	fmt.Println(q.ToSmallString(inverseColor))
 }
 
 // RenderImage returns a QR code as an image.Image