callagent: Introduce the SIPRequests class

Inspired by the MGCPCommands it can create simple requests and
add parameters to the mix...

callagent/SIPRequests.st

@@ -0,0 +1,98 @@
+"
+ (C) 2010-2011 by Holger Hans Peter Freyther
+ All Rights Reserved
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as
+ published by the Free Software Foundation, either version 3 of the
+ License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+"
+
+"TODO: Compare with MGCPCommands and share code..."
+
+Object subclass: SIPRequest [
+    | addr parameters sdp |
+    <comment: 'I should share a parent with MGCPCommand'>
+    <category: 'SIP-Callagent'>
+
+    sipAddr: anAddr [
+        <category: 'accessing'>
+        addr := anAddr
+    ]
+
+    sipAddr [
+        <category: 'accessing'>
+        ^ addr
+    ]
+
+    parameters [
+        <category: 'accessing'>
+        ^ parameters ifNil: [parameters := OrderedCollection new]
+    ]
+
+    sdp: aSDP [
+        <category: 'accessing'>
+        sdp := aSDP
+    ]
+
+    addParameter: name value: aValue [
+        <category: 'accessing'>
+        self parameters add: '%1: %2' % {name. aValue}
+    ]
+
+    asDatagram [
+        | out |
+
+        out := WriteStream on: (String new).
+        out
+            nextPutAll: '%1 %2 SIP/2.0' % {self class verb. self sipAddr};
+            cr; nl.
+
+        self parameters do: [:each |
+            out nextPutAll: each; cr; nl
+        ].
+
+        out cr; nl.
+
+        sdp ifNotNil: [
+            out nextPutAll: sdp
+        ].
+
+        ^ out contents
+    ]
+]
+
+SIPRequest subclass: SIPInviteCommand [
+    <category: 'SIP-Callagent'>
+
+    SIPInviteCommand class >> verb [
+        <category: 'verb'>
+        ^ 'INVITE'
+    ]
+]
+
+SIPRequest subclass: SIPCancelCommand [
+    <category: 'SIP-Callagent'>
+
+    SIPCancelCommand class >> verb [
+        <category: 'verb'>
+        ^ 'CANCEL'
+    ]
+]
+
+SIPRequest subclass: SIPByeCommand [
+    <category: 'SIP-Callagent'>
+
+    SIPByeCommand class >> verb [
+        <category: 'verb'>
+        ^ 'BYE'
+    ]
+]