1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
package calendar
import (
"bytes"
"fmt"
"io"
"net/mail"
"regexp"
"strings"
"time"
ics "github.com/arran4/golang-ical"
)
type Reply struct {
MimeType string
Params map[string]string
CalendarText io.ReadWriter
PlainText io.ReadWriter
Organizers []string
}
func (cr *Reply) AddOrganizer(o string) {
cr.Organizers = append(cr.Organizers, o)
}
// CreateReply parses a ics request and return a ics reply (RFC 2446, Section 3.2.3)
func CreateReply(reader io.Reader, from *mail.Address, partstat string) (*Reply, error) {
cr := Reply{
MimeType: "text/calendar",
Params: map[string]string{
"charset": "UTF-8",
"method": "REPLY",
},
CalendarText: &bytes.Buffer{},
PlainText: &bytes.Buffer{},
}
var (
status ics.ParticipationStatus
action string
)
switch partstat {
case "accept":
status = ics.ParticipationStatusAccepted
action = "accepted"
case "accept-tentative":
status = ics.ParticipationStatusTentative
action = "tentatively accepted"
case "decline":
status = ics.ParticipationStatusDeclined
action = "declined"
default:
return nil, fmt.Errorf("participation status %s is not implemented", partstat)
}
name := from.Name
if name == "" {
name = from.Address
}
fmt.Fprintf(cr.PlainText, "%s has %s this invitation.", name, action)
invite, err := parse(reader)
if err != nil {
return nil, err
}
if ok := invite.request(); !ok {
return nil, fmt.Errorf("no reply is requested")
}
// update invite as a reply
reply := invite
reply.SetMethod(ics.MethodReply)
reply.SetProductId("aerc")
// check all events
for _, vevent := range reply.Events() {
e := event{vevent}
// check if we should answer
if err := e.isReplyRequested(from.Address); err != nil {
return nil, err
}
// make sure we send our reply to the meeting organizer
if organizer := e.GetProperty(ics.ComponentPropertyOrganizer); organizer != nil {
cr.AddOrganizer(organizer.Value)
}
// update attendee participation status
e.updateAttendees(status, from.Address)
// update timestamp
e.SetDtStampTime(time.Now())
// remove any subcomponents of event
e.Components = nil
}
// keep only timezone and event components
reply.clean()
if len(reply.Events()) == 0 {
return nil, fmt.Errorf("no events to respond to")
}
if err := reply.SerializeTo(cr.CalendarText); err != nil {
return nil, err
}
return &cr, nil
}
type calendar struct {
*ics.Calendar
}
func parse(reader io.Reader) (*calendar, error) {
// fix capitalized mailto for parsing of ics file
var sb strings.Builder
io.Copy(&sb, reader)
re := regexp.MustCompile("MAILTO:(.+@)")
str := re.ReplaceAllString(sb.String(), "mailto:${1}")
// parse calendar
invite, err := ics.ParseCalendar(strings.NewReader(str))
if err != nil {
return nil, err
}
return &calendar{invite}, nil
}
func (cal *calendar) request() (ok bool) {
ok = false
for i := range cal.CalendarProperties {
if cal.CalendarProperties[i].IANAToken == string(ics.PropertyMethod) {
if cal.CalendarProperties[i].Value == string(ics.MethodRequest) {
ok = true
return
}
}
}
return
}
func (cal *calendar) clean() {
var clean []ics.Component
for _, comp := range cal.Components {
switch comp.(type) {
case *ics.VTimezone, *ics.VEvent:
clean = append(clean, comp)
default:
continue
}
}
cal.Components = clean
}
type event struct {
*ics.VEvent
}
func (e *event) isReplyRequested(from string) error {
var present bool = false
var rsvp bool = false
for _, a := range e.Attendees() {
if a.Email() == from {
present = true
if r, ok := a.ICalParameters[string(ics.ParameterRsvp)]; ok {
if len(r) > 0 && strings.ToLower(r[0]) == "true" {
rsvp = true
}
}
}
}
if !present {
return fmt.Errorf("we are not invited")
}
if !rsvp {
return fmt.Errorf("we don't have to rsvp")
}
return nil
}
func (e *event) updateAttendees(status ics.ParticipationStatus, from string) {
var clean []ics.IANAProperty
for _, prop := range e.Properties {
if prop.IANAToken == string(ics.ComponentPropertyAttendee) {
att := ics.Attendee{prop}
if att.Email() != from {
continue
}
prop.ICalParameters[string(ics.ParameterParticipationStatus)] = []string{string(status)}
delete(prop.ICalParameters, string(ics.ParameterRsvp))
}
clean = append(clean, prop)
}
e.Properties = clean
}
|
