From a4e0e810039763e891ffea6b8ce665cc629f6f1f Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Wed, 13 May 2020 16:45:10 +0200
Subject: [PATCH] caldav: add Client.MultiGetCalendar

---
 caldav/caldav.go   |  5 +++++
 caldav/client.go   | 32 ++++++++++++++++++++++++++++++++
 caldav/elements.go |  9 +++++++++
 3 files changed, 46 insertions(+)

diff --git a/caldav/caldav.go b/caldav/caldav.go
index d12ff7e..3840c7d 100644
--- a/caldav/caldav.go
+++ b/caldav/caldav.go
@@ -47,6 +47,11 @@ type CalendarQuery struct {
 	CompFilter  CompFilter
 }
 
+type CalendarMultiGet struct {
+	Paths       []string
+	CompRequest CalendarCompRequest
+}
+
 type CalendarObject struct {
 	Path    string
 	ModTime time.Time
diff --git a/caldav/client.go b/caldav/client.go
index 78fb2c1..8f7952e 100644
--- a/caldav/client.go
+++ b/caldav/client.go
@@ -218,6 +218,38 @@ func (c *Client) QueryCalendar(calendar string, query *CalendarQuery) ([]Calenda
 	return decodeCalendarObjectList(ms)
 }
 
+func (c *Client) MultiGetCalendar(path string, multiGet *CalendarMultiGet) ([]CalendarObject, error) {
+	propReq, err := encodeCalendarReq(&multiGet.CompRequest)
+	if err != nil {
+		return nil, err
+	}
+
+	calendarMultiget := calendarMultiget{Prop: propReq}
+
+	if multiGet == nil || len(multiGet.Paths) == 0 {
+		href := internal.Href{Path: path}
+		calendarMultiget.Hrefs = []internal.Href{href}
+	} else {
+		calendarMultiget.Hrefs = make([]internal.Href, len(multiGet.Paths))
+		for i, p := range multiGet.Paths {
+			calendarMultiget.Hrefs[i] = internal.Href{Path: p}
+		}
+	}
+
+	req, err := c.ic.NewXMLRequest("REPORT", path, &calendarMultiget)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Add("Depth", "1")
+
+	ms, err := c.ic.DoMultiStatus(req)
+	if err != nil {
+		return nil, err
+	}
+
+	return decodeCalendarObjectList(ms)
+}
+
 func populateCalendarObject(co *CalendarObject, resp *http.Response) error {
 	if loc := resp.Header.Get("Location"); loc != "" {
 		u, err := url.Parse(loc)
diff --git a/caldav/elements.go b/caldav/elements.go
index 75e9bcb..7fca200 100644
--- a/caldav/elements.go
+++ b/caldav/elements.go
@@ -60,6 +60,15 @@ type calendarQuery struct {
 	// TODO: timezone
 }
 
+// https://tools.ietf.org/html/rfc4791#section-9.10
+type calendarMultiget struct {
+	XMLName  xml.Name        `xml:"urn:ietf:params:xml:ns:caldav calendar-multiget"`
+	Hrefs    []internal.Href `xml:"DAV: href"`
+	Prop     *internal.Prop  `xml:"DAV: prop,omitempty"`
+	AllProp  *struct{}       `xml:"DAV: allprop,omitempty"`
+	PropName *struct{}       `xml:"DAV: propname,omitempty"`
+}
+
 // https://tools.ietf.org/html/rfc4791#section-9.7
 type filter struct {
 	XMLName    xml.Name   `xml:"urn:ietf:params:xml:ns:caldav filter"`