Add --tmux option to replace fzf-tmux script

7 files changed, 286 insertions, 2 deletions

diff --git a/src/core.go b/src/core.go
index 2a07b82a..17b7d1df 100644
--- a/src/core.go
+++ b/src/core.go
@@ -2,6 +2,7 @@
 package fzf
 
 import (
+	"os"
 	"sync"
 	"time"
 
@@ -19,6 +20,10 @@ Matcher  -> EvtHeader         -> Terminal (update header)
 
 // Run starts fzf
 func Run(opts *Options) (int, error) {
+	if opts.Tmux != nil && len(os.Getenv("TMUX")) > 0 {
+		return runTmux(os.Args[1:], opts)
+	}
+
 	if err := postProcessOptions(opts); err != nil {
 		return ExitError, err
 	}
diff --git a/src/functions.go b/src/functions.go
index f16371a2..8d29db74 100644
--- a/src/functions.go
+++ b/src/functions.go
@@ -7,7 +7,7 @@ import (
 )
 
 func writeTemporaryFile(data []string, printSep string) string {
-	f, err := os.CreateTemp("", "fzf-preview-*")
+	f, err := os.CreateTemp("", "fzf-temp-*")
 	if err != nil {
 		// Unable to create temporary file
 		// FIXME: Should we terminate the program?
diff --git a/src/options.go b/src/options.go
index 0265693a..1024038d 100644
--- a/src/options.go
+++ b/src/options.go
@@ -63,6 +63,8 @@ const Usage = `usage: fzf [options]
                            according to the input size.
     --min-height=HEIGHT    Minimum height when --height is given in percent
                            (default: 10)
+    --tmux=OPTS            Start fzf in a tmux popup (requires tmux 3.3+)
+                           [center|top|bottom|left|right][,SIZE[%]][,SIZE[%]]
     --layout=LAYOUT        Choose layout: [default|reverse|reverse-list]
     --border[=STYLE]       Draw border around the finder
                            [rounded|sharp|bold|block|thinblock|double|horizontal|vertical|
@@ -180,6 +182,13 @@ type sizeSpec struct {
 	percent bool
 }
 
+func (s sizeSpec) String() string {
+	if s.percent {
+		return fmt.Sprintf("%d%%", int(s.size))
+	}
+	return fmt.Sprintf("%d", int(s.size))
+}
+
 func defaultMargin() [4]sizeSpec {
 	return [4]sizeSpec{}
 }
@@ -199,8 +208,15 @@ const (
 	posDown
 	posLeft
 	posRight
+	posCenter
 )
 
+type tmuxOptions struct {
+	width    sizeSpec
+	height   sizeSpec
+	position windowPosition
+}
+
 type layoutType int
 
 const (
@@ -248,6 +264,74 @@ func (o *previewOpts) Toggle() {
 	o.hidden = !o.hidden
 }
 
+func parseTmuxOptions(arg string) (*tmuxOptions, error) {
+	var err error
+	opts := tmuxOptions{}
+	tokens := splitRegexp.Split(arg, -1)
+	if len(tokens) == 0 || len(tokens) > 3 {
+		return nil, errors.New("invalid tmux option: " + arg + " (expected: [center|top|bottom|left|right][,SIZE[%]][,SIZE[%]])")
+	}
+
+	// Defaults to 'center'
+	switch tokens[0] {
+	case "top", "up":
+		opts.position = posUp
+		opts.width = sizeSpec{100, true}
+	case "bottom", "down":
+		opts.position = posDown
+		opts.width = sizeSpec{100, true}
+	case "left":
+		opts.position = posLeft
+		opts.height = sizeSpec{100, true}
+	case "right":
+		opts.position = posRight
+		opts.height = sizeSpec{100, true}
+	case "center":
+		opts.position = posCenter
+		opts.width = sizeSpec{50, true}
+		opts.height = sizeSpec{50, true}
+	default:
+		opts.position = posCenter
+		opts.width = sizeSpec{50, true}
+		opts.height = sizeSpec{50, true}
+		tokens = append([]string{"center"}, tokens...)
+	}
+
+	// One size given
+	var size1 sizeSpec
+	if len(tokens) > 1 {
+		if size1, err = parseSize(tokens[1], 100, "size"); err != nil {
+			return nil, err
+		}
+	}
+
+	// Two sizes given
+	var size2 sizeSpec
+	if len(tokens) == 3 {
+		if size2, err = parseSize(tokens[2], 100, "size"); err != nil {
+			return nil, err
+		}
+		opts.width = size1
+		opts.height = size2
+	} else if len(tokens) == 2 {
+		switch tokens[0] {
+		case "top", "up":
+			opts.height = size1
+		case "bottom", "down":
+			opts.height = size1
+		case "left":
+			opts.width = size1
+		case "right":
+			opts.width = size1
+		case "center":
+			opts.width = size1
+			opts.height = size1
+		}
+	}
+
+	return &opts, nil
+}
+
 func parseLabelPosition(opts *labelOpts, arg string) error {
 	opts.column = 0
 	opts.bottom = false
@@ -296,6 +380,7 @@ type walkerOpts struct {
 type Options struct {
 	Input        chan string
 	Output       chan string
+	Tmux         *tmuxOptions
 	Bash         bool
 	Zsh          bool
 	Fish         bool
@@ -1787,6 +1872,16 @@ func parseOptions(opts *Options, allArgs []string) error {
 		case "--version":
 			clearExitingOpts()
 			opts.Version = true
+		case "--tmux":
+			str, err := nextString(allArgs, &i, "tmux options required")
+			if err != nil {
+				return err
+			}
+			if opts.Tmux, err = parseTmuxOptions(str); err != nil {
+				return err
+			}
+		case "--no-tmux":
+			opts.Tmux = nil
 		case "-x", "--extended":
 			opts.Extended = true
 		case "-e", "--exact":
@@ -2264,6 +2359,10 @@ func parseOptions(opts *Options, allArgs []string) error {
 				if opts.FuzzyAlgo, err = parseAlgo(value); err != nil {
 					return err
 				}
+			} else if match, value := optString(arg, "--tmux="); match {
+				if opts.Tmux, err = parseTmuxOptions(value); err != nil {
+					return err
+				}
 			} else if match, value := optString(arg, "--scheme="); match {
 				opts.Scheme = strings.ToLower(value)
 			} else if match, value := optString(arg, "-q", "--query="); match {
@@ -2478,6 +2577,10 @@ func postProcessOptions(opts *Options) error {
 		uniseg.EastAsianAmbiguousWidth = 2
 	}
 
+	if opts.BorderShape == tui.BorderUndefined {
+		opts.BorderShape = tui.BorderNone
+	}
+
 	if err := validateSign(opts.Pointer, "pointer"); err != nil {
 		return err
 	}
diff --git a/src/tmux.go b/src/tmux.go
new file mode 100644
index 00000000..ea1816a5
--- /dev/null
+++ b/src/tmux.go
@@ -0,0 +1,149 @@
+package fzf
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/junegunn/fzf/src/tui"
+	"github.com/junegunn/fzf/src/util"
+)
+
+func escapeSingleQuote(str string) string {
+	return "'" + strings.ReplaceAll(str, "'", "'\\''") + "'"
+}
+
+func runTmux(args []string, opts *Options) (int, error) {
+	ns := time.Now().UnixNano()
+
+	output := filepath.Join(os.TempDir(), fmt.Sprintf("fzf-tmux-output-%d", ns))
+	if err := mkfifo(output, 0666); err != nil {
+		return ExitError, err
+	}
+	defer os.Remove(output)
+
+	// Find fzf executable
+	fzf := "fzf"
+	if found, err := os.Executable(); err == nil {
+		fzf = found
+	}
+
+	// Prepare arguments
+	args = append([]string{"--bind=ctrl-z:ignore"}, args...)
+	if opts.BorderShape == tui.BorderUndefined {
+		args = append(args, "--border")
+	}
+	args = append(args, "--no-height")
+	args = append(args, "--no-tmux")
+	argStr := ""
+	for _, arg := range args {
+		// %q formatting escapes $'foo\nbar' to "foo\nbar"
+		argStr += " " + escapeSingleQuote(arg)
+	}
+
+	// Build command
+	var command string
+	if opts.Input == nil && util.IsTty() {
+		command = fmt.Sprintf(`%q%s > %q`, fzf, argStr, output)
+	} else {
+		input := filepath.Join(os.TempDir(), fmt.Sprintf("fzf-tmux-input-%d", ns))
+		if err := mkfifo(input, 0644); err != nil {
+			return ExitError, err
+		}
+		defer os.Remove(input)
+
+		go func() {
+			inputFile, err := os.OpenFile(input, os.O_WRONLY, 0)
+			if err != nil {
+				return
+			}
+			if opts.Input == nil {
+				io.Copy(inputFile, os.Stdin)
+			} else {
+				for item := range opts.Input {
+					fmt.Fprint(inputFile, item+opts.PrintSep)
+				}
+			}
+			inputFile.Close()
+		}()
+
+		command = fmt.Sprintf(`%q%s < %q > %q`, fzf, argStr, input, output)
+	}
+
+	// Get current directory
+	dir, err := os.Getwd()
+	if err != nil {
+		dir = "."
+	}
+
+	// Set tmux options for popup placement
+	// C        Both    The centre of the terminal
+	// R        -x      The right side of the terminal
+	// P        Both    The bottom left of the pane
+	// M        Both    The mouse position
+	// W        Both    The window position on the status line
+	// S        -y      The line above or below the status line
+	tmuxArgs := []string{"display-popup", "-E", "-B", "-d", dir}
+	switch opts.Tmux.position {
+	case posUp:
+		tmuxArgs = append(tmuxArgs, "-xC", "-y0")
+	case posDown:
+		tmuxArgs = append(tmuxArgs, "-xC", "-yS")
+	case posLeft:
+		tmuxArgs = append(tmuxArgs, "-x0", "-yC")
+	case posRight:
+		tmuxArgs = append(tmuxArgs, "-xR", "-yC")
+	case posCenter:
+		tmuxArgs = append(tmuxArgs, "-xC", "-yC")
+	}
+	tmuxArgs = append(tmuxArgs, "-w"+opts.Tmux.width.String())
+	tmuxArgs = append(tmuxArgs, "-h"+opts.Tmux.height.String())
+
+	// To ensure that the options are processed by a POSIX-compliant shell,
+	// we need to write the command to a temporary file and execute it with sh.
+	exports := os.Environ()
+	for idx, pairStr := range exports {
+		pair := strings.SplitN(pairStr, "=", 2)
+		exports[idx] = fmt.Sprintf("export %s=%s", pair[0], escapeSingleQuote(pair[1]))
+	}
+	temp := writeTemporaryFile(append(exports, command), "\n")
+	defer os.Remove(temp)
+	tmuxArgs = append(tmuxArgs, "sh", temp)
+
+	// Take the output
+	go func() {
+		outputFile, err := os.OpenFile(output, os.O_RDONLY, 0)
+		if err != nil {
+			return
+		}
+		if opts.Output == nil {
+			io.Copy(os.Stdout, outputFile)
+		} else {
+			reader := bufio.NewReader(outputFile)
+			sep := opts.PrintSep[0]
+			for {
+				item, err := reader.ReadString(sep)
+				if err != nil {
+					break
+				}
+				opts.Output <- item
+			}
+		}
+
+		outputFile.Close()
+	}()
+
+	cmd := exec.Command("tmux", tmuxArgs...)
+	if err := cmd.Run(); err != nil {
+		if exitError, ok := err.(*exec.ExitError); ok {
+			return exitError.ExitCode(), err
+		}
+	}
+
+	return ExitOk, nil
+}
diff --git a/src/tmux_unix.go b/src/tmux_unix.go
new file mode 100644
index 00000000..f6ddd58b
--- /dev/null
+++ b/src/tmux_unix.go
@@ -0,0 +1,9 @@
+//go:build !windows
+
+package fzf
+
+import "golang.org/x/sys/unix"
+
+func mkfifo(path string, mode uint32) error {
+	return unix.Mkfifo(path, mode)
+}
diff --git a/src/tmux_windows.go b/src/tmux_windows.go
new file mode 100644
index 00000000..bd356364
--- /dev/null
+++ b/src/tmux_windows.go
@@ -0,0 +1,17 @@
+//go:build windows
+
+package fzf
+
+import (
+	"os/exec"
+	"strconv"
+)
+
+func mkfifo(path string, mode uint32) error {
+	m := strconv.FormatUint(uint64(mode), 8)
+	cmd := exec.Command("mkfifo", "-m", m, path)
+	if err := cmd.Run(); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/src/tui/tui.go b/src/tui/tui.go
index aed41a9d..ee497740 100644
--- a/src/tui/tui.go
+++ b/src/tui/tui.go
@@ -356,7 +356,8 @@ type MouseEvent struct {
 type BorderShape int
 
 const (
-	BorderNone BorderShape = iota
+	BorderUndefined BorderShape = iota
+	BorderNone
 	BorderRounded
 	BorderSharp
 	BorderBold