1 files changed, 59 insertions, 0 deletions
diff --git a/git_format_patch.go b/git_format_patch.go
new file mode 100644
index 0000000..c899ed5
--- /dev/null
+++ b/git_format_patch.go
@@ -0,0 +1,59 @@
+package main
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/go-git/go-git/v5/plumbing/object"
+	"go.lindenii.runxiyu.org/lindenii-common/misc"
+)
+
+var err_get_patch = errors.New("Failed to get patch from commit")
+
+func format_patch_from_commit(commit *object.Commit) (string, error) {
+	parent, err := commit.Parent(0)
+	if err != nil {
+		return "", err
+	}
+
+	var patch *object.Patch
+	patch, err = parent.Patch(commit)
+	if err != nil {
+		return "", misc.Wrap_one_error(err_get_patch, err)
+	}
+
+	var buf bytes.Buffer
+
+	author := commit.Author
+	date := author.When.Format(time.RFC1123Z)
+
+	commit_msg_title, commit_msg_details, _ := strings.Cut(commit.Message, "\n")
+
+	fmt.Fprintf(&buf, "From %s Mon Sep 17 00:00:00 2001\n", commit.Hash)
+	fmt.Fprintf(&buf, "From: %s <%s>\n", author.Name, author.Email)
+	fmt.Fprintf(&buf, "Date: %s\n", date)
+	fmt.Fprintf(&buf, "Subject: [PATCH] %s\n\n", commit_msg_title)
+
+	if commit_msg_details != "" {
+		fmt.Println("fdsafsad")
+		commit_msg_details_first_line, commit_msg_details_rest, _ := strings.Cut(commit_msg_details, "\n")
+		if strings.TrimSpace(commit_msg_details_first_line) == "" {
+			commit_msg_details = commit_msg_details_rest
+		}
+		buf.WriteString(commit_msg_details)
+		buf.WriteString("\n")
+	}
+	buf.WriteString("---\n")
+	fmt.Fprint(&buf, patch.Stats().String())
+	fmt.Fprintln(&buf)
+
+	buf.WriteString(patch.String())
+
+	fmt.Fprintf(&buf, "\n-- \n2.48.1\n")
+
+	return buf.String(), nil
+}
+