Rename module to osc, and use subcommands via spf13/cobra

1 files changed, 153 insertions, 144 deletions

diff --git a/main.go b/main.go
index f7161a5..85ae9d0 100644
--- a/main.go
+++ b/main.go
@@ -3,7 +3,6 @@ package main
 import (
 	"bufio"
 	"encoding/base64"
-	"flag"
 	"fmt"
 	"github.com/gdamore/tcell/v2"
 	"github.com/jba/slog/handlers/loghandler"
@@ -13,12 +12,16 @@ import (
 	"os"
 	"strings"
 	"time"
+
+	"github.com/spf13/cobra"
 )
 
 var (
-	oscOpen  string = "\x1b]52;c;"
-	oscClose string = "\a"
-	isScreen bool
+	oscOpen     string = "\x1b]52;c;"
+	oscClose    string = "\a"
+	isScreen    bool
+	verboseFlag bool
+	logfileFlag string
 )
 
 func encode(fname string, encoder io.WriteCloser) {
@@ -54,44 +57,8 @@ func closetty(tty tcell.Tty) {
 	tty.Close()
 }
 
-func _main() int {
-	var fnames []string
+func initLogging() {
 	var err error
-	var exitCode int
-
-	flag.Usage = func() {
-		template := `Reads or writes the system clipboard using the ANSI OSC52 escape sequence.
-
-Usage:
-
-COPY mode (default):
-
-    %s [file1 [...fileN]]
-
-With no arguments, will read from stdin.
-
-PASTE mode:
-
-    %s --paste
-
-Outputs clipboard contents to stdout.
-
-Options:
-`
-		fmt.Fprintf(flag.CommandLine.Output(), template, os.Args[0], os.Args[0])
-		flag.PrintDefaults()
-	}
-
-	var pasteFlag bool
-	var verboseFlag bool
-	var logfileFlag string
-	flag.BoolVar(&pasteFlag, "paste", pasteFlag, "paste operation")
-	flag.BoolVar(&verboseFlag, "verbose", verboseFlag, "verbose logging")
-	flag.BoolVar(&verboseFlag, "v", verboseFlag, "verbose logging")
-	flag.StringVar(&logfileFlag, "logFile", logfileFlag, "redirect logs to file")
-
-	flag.Parse()
-
 	logLevel := &slog.LevelVar{} // INFO
 	logOutput := os.Stdout
 
@@ -113,7 +80,9 @@ Options:
 
 	slog.SetDefault(logger)
 	slog.Debug("logging started")
+}
 
+func identifyTerm() {
 	if ti, err := tcell.LookupTerminfo(os.Getenv("TERM")); err != nil {
 		slog.Error(fmt.Sprintf("Failed to lookup terminfo: %v", err))
 	} else {
@@ -128,129 +97,169 @@ Options:
 		oscOpen = "\x1bP" + oscOpen
 		oscClose = oscClose + "\x1b\\"
 	}
+}
+
+func copy(fnames []string) error {
+	// copy
+	if len(fnames) == 0 {
+		fnames = []string{"-"}
+	}
 
-	if !pasteFlag {
-		// copy
-		if len(flag.Args()) > 0 {
-			fnames = flag.Args()
-		} else {
-			fnames = []string{"-"}
+	slog.Debug("Beginning osc52 copy operation")
+	err := func() error {
+		tty, err := opentty()
+		if err != nil {
+			slog.Error(fmt.Sprintf("opentty: %v", err))
+			return err
 		}
+		defer closetty(tty)
 
-		slog.Debug("Beginning osc52 copy operation")
-		func() {
-			tty, err := opentty()
-			if err != nil {
-				slog.Error(fmt.Sprintf("opentty: %v", err))
-				exitCode = 1
-				return
-			}
-			defer closetty(tty)
+		// Open buffered output, using default max OSC52 length as buffer size
+		// TODO limit size
+		out := bufio.NewWriterSize(tty, 1000000)
 
-			// Open buffered output, using default max OSC52 length as buffer size
-			// TODO limit size
-			out := bufio.NewWriterSize(tty, 1000000)
+		// Start OSC52
+		fmt.Fprint(out, oscOpen)
 
-			// Start OSC52
-			fmt.Fprint(out, oscOpen)
+		b64 := base64.NewEncoder(base64.StdEncoding, out)
+		for _, fname := range fnames {
+			encode(fname, b64)
+		}
+		b64.Close()
 
-			b64 := base64.NewEncoder(base64.StdEncoding, out)
-			for _, fname := range fnames {
-				encode(fname, b64)
-			}
-			b64.Close()
+		// End OSC52
+		fmt.Fprint(out, oscClose)
 
-			// End OSC52
-			fmt.Fprint(out, oscClose)
+		out.Flush()
+		return nil
+	}()
+	slog.Debug("Ended osc52")
+	return err
+}
 
-			out.Flush()
-		}()
-		slog.Debug("Ended osc52")
-	} else {
-		// paste
-
-		slog.Debug("Beginning osc52 paste operation")
-		data := func() []byte {
-			tty, err := opentty()
-			if err != nil {
-				slog.Error(fmt.Sprintf("opentty: %v", err))
-				exitCode = 1
-				return nil
+func paste() error {
+	slog.Debug("Beginning osc52 paste operation")
+	if data, err := func() ([]byte, error) {
+		tty, err := opentty()
+		if err != nil {
+			slog.Error(fmt.Sprintf("opentty: %v", err))
+			return nil, err
+		}
+		defer closetty(tty)
+
+		// Start OSC52
+		fmt.Fprint(tty, oscOpen+"?"+oscClose)
+
+		ttyReader := bufio.NewReader(tty)
+		buf := make([]byte, 0, 1024)
+
+		// time out intial read in 100 milliseconds
+		readChan := make(chan byte, 1)
+		defer close(readChan)
+		go func() {
+			if b, e := ttyReader.ReadByte(); e != nil {
+				slog.Debug(fmt.Sprintf("Initial ReadByte error: %v", e))
+			} else {
+				readChan <- b
 			}
-			defer closetty(tty)
-
-			// Start OSC52
-			fmt.Fprint(tty, oscOpen+"?"+oscClose)
-
-			ttyReader := bufio.NewReader(tty)
-			buf := make([]byte, 0, 1024)
-
-			// time out intial read in 100 milliseconds
-			readChan := make(chan byte, 1)
-			defer close(readChan)
-			go func() {
-				if b, e := ttyReader.ReadByte(); e != nil {
-					slog.Debug(fmt.Sprintf("Initial ReadByte error: %v", e))
-				} else {
-					readChan <- b
+		}()
+		select {
+		case b := <-readChan:
+			buf = append(buf, b)
+		case <-time.After(100 * time.Millisecond):
+			slog.Debug("tty read timeout")
+			return nil, fmt.Errorf("tty read timeout")
+		}
+
+		for {
+			if b, e := ttyReader.ReadByte(); e != nil {
+				slog.Error(fmt.Sprintf("ReadByte: %v", e))
+				return nil, e
+			} else {
+				slog.Debug(fmt.Sprintf("Read: %x '%s'", b, string(b)))
+				// Terminator might be BEL (\a) or ESC-backslash (\x1b\\)
+				if b == '\a' {
+					break
 				}
-			}()
-			select {
-			case b := <-readChan:
 				buf = append(buf, b)
-			case <-time.After(100 * time.Millisecond):
-				slog.Debug("tty read timeout")
-				exitCode = 1
-				return nil
-			}
-
-			for {
-				if b, e := ttyReader.ReadByte(); e != nil {
-					slog.Error(fmt.Sprintf("ReadByte: %v", e))
-					exitCode = 1
-					return nil
-				} else {
-					slog.Debug(fmt.Sprintf("Read: %x '%s'", b, string(b)))
-					// Terminator might be BEL (\a) or ESC-backslash (\x1b\\)
-					if b == '\a' {
-						break
-					}
-					buf = append(buf, b)
-					// Skip initial 7 bytes of response
-					if len(buf) > 9 && buf[len(buf)-2] == '\x1b' && buf[len(buf)-1] == '\\' {
-						buf = buf[:len(buf)-2]
-						break
-					}
+				// Skip initial 7 bytes of response
+				if len(buf) > 9 && buf[len(buf)-2] == '\x1b' && buf[len(buf)-1] == '\\' {
+					buf = buf[:len(buf)-2]
+					break
 				}
 			}
+		}
 
-			slog.Debug(fmt.Sprintf("buf[:7]: %q", buf[:7]))
-			buf = buf[7:]
-
-			decodedBuf := make([]byte, base64.StdEncoding.DecodedLen(len(buf)))
-			n, err := base64.StdEncoding.Decode(decodedBuf, []byte(buf))
-			if err != nil {
-				slog.Error(fmt.Sprintf("decode error: %v", err))
-				exitCode = 1
-				return nil
-			}
-			decodedBuf = decodedBuf[:n]
+		slog.Debug(fmt.Sprintf("buf[:7]: %q", buf[:7]))
+		buf = buf[7:]
 
-			return decodedBuf
-		}()
+		decodedBuf := make([]byte, base64.StdEncoding.DecodedLen(len(buf)))
+		n, err := base64.StdEncoding.Decode(decodedBuf, []byte(buf))
+		if err != nil {
+			slog.Error(fmt.Sprintf("decode error: %v", err))
+			return nil, err
+		}
+		decodedBuf = decodedBuf[:n]
 
-		if data != nil {
-			if _, err := os.Stdout.Write(data); err != nil {
-				slog.Error(fmt.Sprintf("Error writing to stdout: %v", err))
-				exitCode = 1
-			}
+		return decodedBuf, nil
+	}(); err != nil {
+		return err
+	} else {
+		if _, err = os.Stdout.Write(data); err != nil {
+			slog.Error(fmt.Sprintf("Error writing to stdout: %v", err))
+			return err
 		}
-		slog.Debug("Ended osc52")
 	}
+	slog.Debug("Ended osc52")
 
-	return exitCode
+	return nil
+}
+
+var copyCmd = &cobra.Command{
+	Use:   "copy",
+	Short: "Copies input to the system clipboard",
+	Long: `Copies input to the system clipboard. Usage:
+
+osc copy [file1 [...fileN]]
+
+With no arguments, will read from stdin.`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		initLogging()
+		identifyTerm()
+		return copy(args)
+	},
+}
+
+var pasteCmd = &cobra.Command{
+	Use:   "paste",
+	Short: "Outputs system clipboard contents to stdout",
+	Long: `Outputs system clipboard contents to stdout. Usage:
+
+osc paste`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		initLogging()
+		identifyTerm()
+		return paste()
+	},
+}
+
+var rootCmd = &cobra.Command{
+	Use:   "osc",
+	Short: "Reads or writes the system clipboard using the ANSI OSC52 escape sequence",
+	Long:  `Reads or writes the system clipboard using the ANSI OSC52 escape sequence.`,
+}
+
+func init() {
+	rootCmd.PersistentFlags().BoolVarP(&verboseFlag, "verbose", "v", false, "verbose logging")
+	rootCmd.PersistentFlags().StringVarP(&logfileFlag, "log", "l", "", "write logs to file")
+
+	rootCmd.AddCommand(copyCmd)
+	rootCmd.AddCommand(pasteCmd)
 }
 
 func main() {
-	os.Exit(_main())
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
 }