From 62ff0f0c01aa2006cc57fc8364418758bdc3a129 Mon Sep 17 00:00:00 2001
From: bouncepaw <bouncepaw2@ya.ru>
Date: Wed, 21 Oct 2020 23:37:39 +0500
Subject: [PATCH] Check for name collisions of subhyphae when renaming
 recursively

---
 README.md |  8 ++++++--
 hypha.go  | 19 +++++++++++++------
 main.go   |  2 +-
 3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/README.md b/README.md
index 1ff54b3..f564532 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,11 @@
-# 🍄 MycorrhizaWiki 0.9
+# 🍄 MycorrhizaWiki 0.10
 A wiki engine.
 
+This is the development branch for version 0.10. Features planned for this version:
+* [ ] Mycomarkup
+* [ ] CLI options
+* [ ] CSS improvements
+
 ## Building
 ```sh
 git clone --recurse-submodules https://github.com/bouncepaw/mycorrhiza
@@ -34,4 +39,3 @@ Help is always needed. We have a [tg chat](https://t.me/mycorrhizadev) where som
 * Tagging system
 * Authorization
 * Better history viewing
-* More markups
diff --git a/hypha.go b/hypha.go
index 74a8685..f184ff3 100644
--- a/hypha.go
+++ b/hypha.go
@@ -61,10 +61,13 @@ func findHyphaeToRename(hyphaName string, recursive bool) []string {
 	return hyphae
 }
 
-func renamingPairs(hyphaNames []string, replaceName func(string) string) map[string]string {
+func renamingPairs(hyphaNames []string, replaceName func(string) string) (map[string]string, error) {
 	renameMap := make(map[string]string)
 	for _, hn := range hyphaNames {
 		if hd, ok := HyphaStorage[hn]; ok {
+			if _, nameUsed := HyphaStorage[replaceName(hn)]; nameUsed {
+				return nil, errors.New("Hypha " + replaceName(hn) + " already exists")
+			}
 			if hd.textPath != "" {
 				renameMap[hd.textPath] = replaceName(hd.textPath)
 			}
@@ -73,7 +76,7 @@ func renamingPairs(hyphaNames []string, replaceName func(string) string) map[str
 			}
 		}
 	}
-	return renameMap
+	return renameMap, nil
 }
 
 // word Data is plural here
@@ -94,11 +97,15 @@ func (hd *HyphaData) RenameHypha(hyphaName, newName string, recursive bool) *his
 		replaceName = func(str string) string {
 			return strings.Replace(str, hyphaName, newName, 1)
 		}
-		hyphaNames = findHyphaeToRename(hyphaName, recursive)
-		renameMap  = renamingPairs(hyphaNames, replaceName)
-		renameMsg  = "Rename ‘%s’ to ‘%s’"
-		hop        = history.Operation(history.TypeRenameHypha)
+		hyphaNames     = findHyphaeToRename(hyphaName, recursive)
+		renameMap, err = renamingPairs(hyphaNames, replaceName)
+		renameMsg      = "Rename ‘%s’ to ‘%s’"
+		hop            = history.Operation(history.TypeRenameHypha)
 	)
+	if err != nil {
+		hop.Errs = append(hop.Errs, err)
+		return hop
+	}
 	if recursive {
 		renameMsg += " recursively"
 	}
diff --git a/main.go b/main.go
index 7956270..e8ac7fd 100644
--- a/main.go
+++ b/main.go
@@ -40,7 +40,7 @@ func HttpErr(w http.ResponseWriter, status int, name, title, errMsg string) {
 	w.Header().Set("Content-Type", "text/html;charset=utf-8")
 	w.WriteHeader(status)
 	fmt.Fprint(w, base(title, fmt.Sprintf(
-		`<p>%s. <a href="/page/%s">Go back to the hypha.<a></p>`,
+		`<main><p>%s. <a href="/page/%s">Go back to the hypha.<a></p></main>`,
 		errMsg, name)))
 }