From 0ea114ec795a19dea210f374da3aa8b7bd7669e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thomas=20M=C3=BCller?=
 <1005065+DeepDiver1975@users.noreply.github.com>
Date: Thu, 8 Feb 2024 17:08:41 +0100
Subject: [PATCH] caldav: add MKCOL support

---
 caldav/elements.go    |  7 +++++++
 caldav/server.go      | 26 +++++++++++++++++++++++++-
 caldav/server_test.go |  4 ++++
 3 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/caldav/elements.go b/caldav/elements.go
index 255ab7a..5759f31 100644
--- a/caldav/elements.go
+++ b/caldav/elements.go
@@ -228,3 +228,10 @@ func (r *reportReq) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 
 	return d.DecodeElement(v, &start)
 }
+
+type mkcolReq struct {
+	XMLName      xml.Name              `xml:"DAV: mkcol"`
+	ResourceType internal.ResourceType `xml:"set>prop>resourcetype"`
+	DisplayName  string                `xml:"set>prop>displayname"`
+	// TODO this could theoretically contain all addressbook properties?
+}
diff --git a/caldav/server.go b/caldav/server.go
index b1ce9ad..f69a0bd 100644
--- a/caldav/server.go
+++ b/caldav/server.go
@@ -30,8 +30,11 @@ type PutCalendarObjectOptions struct {
 // Backend is a CalDAV server backend.
 type Backend interface {
 	CalendarHomeSetPath(ctx context.Context) (string, error)
+
+	CreateCalendar(ctx context.Context, calendar *Calendar) error
 	ListCalendars(ctx context.Context) ([]Calendar, error)
 	GetCalendar(ctx context.Context, path string) (*Calendar, error)
+
 	GetCalendarObject(ctx context.Context, path string, req *CalendarCompRequest) (*CalendarObject, error)
 	ListCalendarObjects(ctx context.Context, path string, req *CalendarCompRequest) ([]CalendarObject, error)
 	QueryCalendarObjects(ctx context.Context, path string, query *CalendarQuery) ([]CalendarObject, error)
@@ -702,7 +705,28 @@ func (b *backend) Delete(r *http.Request) error {
 }
 
 func (b *backend) Mkcol(r *http.Request) error {
-	return internal.HTTPErrorf(http.StatusNotImplemented, "caldav: Mkcol not implemented")
+	if b.resourceTypeAtPath(r.URL.Path) != resourceTypeCalendar {
+		return internal.HTTPErrorf(http.StatusForbidden, "caldav: calendar creation not allowed at given location")
+	}
+
+	cal := Calendar{
+		Path: r.URL.Path,
+	}
+
+	if !internal.IsRequestBodyEmpty(r) {
+		var m mkcolReq
+		if err := internal.DecodeXMLRequest(r, &m); err != nil {
+			return internal.HTTPErrorf(http.StatusBadRequest, "carddav: error parsing mkcol request: %s", err.Error())
+		}
+
+		if !m.ResourceType.Is(internal.CollectionName) || !m.ResourceType.Is(calendarName) {
+			return internal.HTTPErrorf(http.StatusBadRequest, "carddav: unexpected resource type")
+		}
+		cal.Name = m.DisplayName
+		// TODO ...
+	}
+
+	return b.Backend.CreateCalendar(r.Context(), &cal)
 }
 
 func (b *backend) Copy(r *http.Request, dest *internal.Href, recursive, overwrite bool) (created bool, err error) {
diff --git a/caldav/server_test.go b/caldav/server_test.go
index 26acd56..3d1e63c 100644
--- a/caldav/server_test.go
+++ b/caldav/server_test.go
@@ -182,6 +182,10 @@ type testBackend struct {
 	objectMap map[string][]CalendarObject
 }
 
+func (t testBackend) CreateCalendar(ctx context.Context, calendar *Calendar) error {
+	return nil
+}
+
 func (t testBackend) ListCalendars(ctx context.Context) ([]Calendar, error) {
 	return t.calendars, nil
 }