Merge pull request AY2324S2-CS2103T-T12-1#73 from Teee728/Update-UG-D…

…G-for-mail-feature

Update UG, DG and add sequence diagram for mail feature

docs/DeveloperGuide.md

@@ -219,6 +219,14 @@ the command is executed:
 * The history size could be made to be configurable by the user.
 * The history could be saved to disk so that it persists between app launches.
 
+### Send email directly feature
+
+The following sequence diagram shows what happens as the user double clicks on the email address
+<puml src="diagrams/SendEmailSequenceDiagram.puml" alt="Sequence Diagram for sending an email" />
+
+#### Possible enhancements
+* There can be a feature where multiple emails can be selected to send a mass email to them.
+
 ### \[Proposed\] Undo/redo feature
 
 #### Proposed Implementation 

docs/diagrams/ModelClassDiagram.puml

@@ -18,6 +18,7 @@ Class Address
 Class Email
 Class Name
 Class Phone
+Class GitHubUsername
 Class Tag
 Class TechStack
 

docs/diagrams/SendEmailSequenceDiagram.puml

@@ -0,0 +1,17 @@
+@startuml
+actor User
+participant "ContactList View" as ContactListView
+participant "MailApp" as MailApp
+participant "Mail Application" as MailApplication
+
+User -> ContactListView : Clicks on email address
+activate ContactListView
+ContactListView -> MailApp : handleEmailClicked()
+activate MailApp
+MailApp -> MailApplication : openDefaultMailApp(email)
+activate MailApplication
+MailApplication --> User : Mail application opens with selected email
+deactivate MailApplication
+deactivate MailApp
+deactivate ContactListView
+@enduml