From 0f181f8920bf60290f2f76503c496a9a6fe73b96 Mon Sep 17 00:00:00 2001
From: Tim Culverhouse <tim@timculverhouse.com>
Date: Sat, 10 May 2025 07:43:36 -0500
Subject: [PATCH] pr(create): open patches in $EDITOR before sending

---
 git/git.go   | 36 ++++++++++++++++++++++++++++++++++++
 knit.go      | 24 +++++++++++++++++++++++-
 pr/create.go | 32 ++++++++++++++++++++++++++------
 3 files changed, 85 insertions(+), 7 deletions(-)

diff --git a/git/git.go b/git/git.go
index 9d5c865..7d22555 100644
--- a/git/git.go
+++ b/git/git.go
@@ -4,7 +4,10 @@ import (
 	"bufio"
 	"fmt"
 	"net/url"
+	"os"
 	"os/exec"
+	"path"
+	"sort"
 	"strings"
 )
 
@@ -98,6 +101,39 @@ func FormatPatch(revRange string) (string, error) {
 	return string(output), nil
 }
 
+func FormatPatchToTmp(revRange string) ([]string, error) {
+	tmpDir, err := os.MkdirTemp("", "knit-patches-")
+	if err != nil {
+		return nil, err
+	}
+
+	cmd := exec.Command(
+		"git",
+		"format-patch",
+		"--output-directory",
+		tmpDir,
+		revRange,
+	)
+	if err := cmd.Run(); err != nil {
+		return nil, err
+	}
+
+	entries, err := os.ReadDir(tmpDir)
+	if err != nil {
+		return nil, err
+	}
+
+	var paths []string
+	for _, entry := range entries {
+		if entry.IsDir() {
+			continue
+		}
+		paths = append(paths, path.Join(tmpDir, entry.Name()))
+	}
+	sort.Strings(paths)
+	return paths, nil
+}
+
 func RemoteBranches(remote string) ([]string, error) {
 	cmd := exec.Command("git", "branch", "--remotes", "--list", remote+"*")
 
diff --git a/knit.go b/knit.go
index 4886598..684cd23 100644
--- a/knit.go
+++ b/knit.go
@@ -1,6 +1,10 @@
 package knit
 
-import "errors"
+import (
+	"errors"
+	"os"
+	"os/exec"
+)
 
 // DefaultHost is the default host for tangled.sh services
 const DefaultHost = "tangled.sh"
@@ -11,3 +15,21 @@ const DefaultKnot = "knot1.tangled.sh"
 // ErrRequiresAuth is returned when a command requires authentication but the
 // user has not authenticated with the host
 var ErrRequiresAuth = errors.New("authentication required")
+
+func Editor() string {
+	e := os.Getenv("EDITOR")
+	if e != "" {
+		return e
+	}
+
+	options := []string{"nvim", "vim", "nano"}
+	for _, opt := range options {
+		_, err := exec.LookPath(opt)
+		if err != nil {
+			continue
+		}
+		return opt
+	}
+
+	return "vi"
+}
diff --git a/pr/create.go b/pr/create.go
index e73e48e..f9b798a 100644
--- a/pr/create.go
+++ b/pr/create.go
@@ -6,6 +6,8 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"os"
+	"os/exec"
 	"path"
 	"strings"
 	"sync"
@@ -36,6 +38,29 @@ func Create(cmd *cobra.Command, args []string) error {
 	}
 	_ = client
 
+	paths, err := git.FormatPatchToTmp(args[0])
+	if err != nil {
+		return err
+	}
+
+	editor := exec.Command(knit.Editor(), paths...)
+	editor.Stdout = os.Stdout
+	editor.Stderr = os.Stderr
+	editor.Stdin = os.Stdin
+	if err := editor.Run(); err != nil {
+		return err
+	}
+
+	// Combine the result into a single slice
+	var patch []byte
+	for _, p := range paths {
+		b, err := os.ReadFile(p)
+		if err != nil {
+			return err
+		}
+		patch = append(patch, b...)
+	}
+
 	// Get available remotes
 	remotes, err := git.Remotes()
 	if err != nil {
@@ -60,11 +85,6 @@ func Create(cmd *cobra.Command, args []string) error {
 			Run()
 	}
 
-	patch, err := git.FormatPatch(args[0])
-	if err != nil {
-		return err
-	}
-
 	branches, err := git.RemoteBranches(remote.Name)
 	if err != nil {
 		return err
@@ -118,7 +138,7 @@ func Create(cmd *cobra.Command, args []string) error {
 	form.Add("title", title)
 	form.Add("body", description)
 	form.Add("targetBranch", targetBranch)
-	form.Add("patch", patch)
+	form.Add("patch", string(patch))
 
 	p := remote.Path
 	if !strings.HasPrefix(p, "@") {
-- 
2.51.2