1package diff
 2
 3import (
 4	"strings"
 5
 6	"github.com/aymanbagabas/go-udiff"
 7)
 8
 9// GenerateDiff creates a unified diff from two file contents.
10func GenerateDiff(beforeContent, afterContent, fileName string) (string, int, int) {
11	beforeContent = strings.ReplaceAll(beforeContent, "\r\n", "\n")
12	afterContent = strings.ReplaceAll(afterContent, "\r\n", "\n")
13
14	fileName = strings.TrimPrefix(fileName, "/")
15
16	var (
17		unified   = udiff.Unified("a/"+fileName, "b/"+fileName, beforeContent, afterContent)
18		additions = 0
19		removals  = 0
20	)
21
22	lines := strings.SplitSeq(unified, "\n")
23	for line := range lines {
24		if strings.HasPrefix(line, "+") && !strings.HasPrefix(line, "+++") {
25			additions++
26		} else if strings.HasPrefix(line, "-") && !strings.HasPrefix(line, "---") {
27			removals++
28		}
29	}
30
31	return unified, additions, removals
32}