ClubHub Developer Guide

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Acknowledgements

• Project scaffold adapted from SE-EDU: AddressBook-Level3 (AB3) https://github.com/se-edu/addressbook-level3
• Documentation structure and diagrams adapted from SE-EDU guides
• UI built with JavaFX https://openjfx.io/
• JSON serialization with Jackson https://github.com/FasterXML/jackson
• Testing with JUnit 5 https://junit.org/junit5/
• PlantUML for diagrams https://plantuml.com/

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Setting up, getting started

Refer to the guide Setting up and getting started.

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Design

Architecture

The Architecture Diagram given above explains the high-level design of the App.

Given below is a quick overview of main components and how they interact with each other.

Main components of the architecture

Main (consisting of classes Main and MainApp) is in charge of the app launch and shut down.

• At app launch, it initializes the other components in the correct sequence, and connects them up with each other.
• At shut down, it shuts down the other components and invokes cleanup methods where necessary.

The bulk of the app's work is done by the following four components:

• UI: The UI of the App.
• Logic: The command executor.
• Model: Holds the data of the App in memory.
• Storage: Reads data from, and writes data to, the hard disk.

Commons represents a collection of classes used by multiple other components.

How the architecture components interact with each other

The Sequence Diagram below shows how the components interact with each other for the scenario where the user issues the command delete 1.

Each of the four main components (also shown in the diagram above),

• defines its API in an interface with the same name as the Component.
• implements its functionality using a concrete {Component Name}Manager class (which follows the corresponding API interface mentioned in the previous point.

For example, the Logic component defines its API in the Logic.java interface and implements its functionality using the LogicManager.java class which follows the Logic interface. Other components interact with a given component through its interface rather than the concrete class (reason: to prevent outside component's being coupled to the implementation of a component), as illustrated in the (partial) class diagram below.

The sections below give more details of each component.

UI component

The API of this component is specified in Ui.java, which defines the interface with the start(Stage primaryStage) method. The concrete implementation is provided by UiManager.java.

The UI consists of a MainWindow that is made up of parts e.g.CommandBox, ResultDisplay, PersonListPanel, StatusBarFooter etc. All these, including the MainWindow, inherit from the abstract UiPart class which captures the commonalities between classes that represent parts of the visible GUI.

The UI component uses the JavaFx UI framework. The layout of these UI parts are defined in matching .fxml files that are in the src/main/resources/view folder. For example, the layout of the MainWindow is specified in MainWindow.fxml

The UI component,

• executes user commands using the Logic component.
• listens for changes to Model data so that the UI can be updated with the modified data.
• keeps a reference to the Logic component, because the UI relies on the Logic to execute commands.
• depends on some classes in the Model component, as it displays Person object residing in the Model.

Logic component

API : Logic.java

Here's a (partial) class diagram of the Logic component:

The sequence diagram below illustrates the interactions within the Logic component, taking execute("delete 1") API call as an example.

How the Logic component works:

1. When Logic is called upon to execute a command, it is passed to an AddressBookParser object which in turn creates a parser that matches the command (e.g., DeleteCommandParser) and uses it to parse the command.
2. This results in a Command object (more precisely, an object of one of its subclasses e.g., DeleteCommand) which is executed by the LogicManager.
3. The command can communicate with the Model when it is executed (e.g. to delete a person).
   Note that although this is shown as a single step in the diagram above (for simplicity), in the code it can take several interactions (between the command object and the Model) to achieve.
4. The result of the command execution is encapsulated as a CommandResult object which is returned back from Logic.

Here are the other classes in Logic (omitted from the class diagram above) that are used for parsing a user command:

How the parsing works:

• When called upon to parse a user command, the AddressBookParser class creates an XYZCommandParser (XYZ is a placeholder for the specific command name e.g., AddCommandParser) which uses the other classes shown above to parse the user command and create a XYZCommand object (e.g., AddCommand) which the AddressBookParser returns back as a Command object.
• All XYZCommandParser classes (e.g., AddCommandParser, DeleteCommandParser, ...) inherit from the Parser interface so that they can be treated similarly where possible e.g, during testing.

Model component

API : Model.java

The Model component,

• stores the address book data i.e., all Person objects (which are contained in a UniquePersonList object).
• stores the currently 'selected' Person objects (e.g., results of a search query) as a separate filtered list which is exposed to outsiders as an unmodifiable ObservableList<Person> that can be 'observed' e.g. the UI can be bound to this list so that the UI automatically updates when the data in the list change.
• stores a UserPref object that represents the user’s preferences. This is exposed to the outside as a ReadOnlyUserPref objects.
• does not depend on any of the other three components (as the Model represents data entities of the domain, they should make sense on their own without depending on other components)

Storage component

API : Storage.java

The Storage component,

• can save both address book data and user preference data in JSON format, and read them back into corresponding objects.
• inherits from both AddressBookStorage and UserPrefStorage, which means it can be treated as either one (if only the functionality of only one is needed).
• depends on some classes in the Model component (because the Storage component's job is to save/retrieve objects that belong to the Model)

Common classes

Classes used by multiple components are in the seedu.address.commons package.

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Implementation

This section describes some noteworthy details on how certain features are implemented.

Undo/redo feature

Implementation (current)

The undo/redo mechanism is implemented via VersionedAddressBook, which maintains two stacks:

• addressBookStateHistory (undo stack)
• addressBookRedoHistory (redo stack)

APIs:

• VersionedAddressBook#commit() saves a copy of the current state to the undo stack and clears the redo stack.
• VersionedAddressBook#undo() pushes the current state onto the redo stack, pops the previous state from the undo stack, and calls resetData(previousState).
• VersionedAddressBook#redo() pushes the current state onto the undo stack, pops from the redo stack, and calls resetData(nextState).

Model surface:

• Model#commit(), Model#undo(), Model#redo() delegate to the above VersionedAddressBook methods.
• On successful undo()/redo(), ModelManager refreshes filtered lists via updateFilteredPersonList, updateFilteredEventList, and updateFilteredTaskList to keep the UI consistent.

Supported commands: All commands that modify data are undoable, including:

• Member operations: add, edit, delete, clear
• Event operations: addevent, deleteevent, setexpense
• Task operations: addtask, deletetask, marktask, unmarktask
• Attendance operations: addattendance, markattendance, unmarkattendance, removeAttendees
• Budget operations: budgetset, budgetreset

Read-only commands (like list, find, showattendance, viewattendees, budgetreport) do not commit state and cannot be undone.

Given below is an example usage scenario and how the undo/redo mechanism behaves at each step.

Step 1. The user launches the application for the first time. The VersionedAddressBook will be initialized with the initial address book state, and the currentStatePointer pointing to that single address book state.

Step 2. The user executes delete 5 command to delete the 5th person in the address book. The delete command calls Model#commitAddressBook(), causing the modified state of the address book after the delete 5 command executes to be saved in the addressBookStateList, and the currentStatePointer is shifted to the newly inserted address book state.

Step 3. The user executes add n/David …​ to add a new person. The add command also calls Model#commitAddressBook(), causing another modified address book state to be saved into the addressBookStateList.

Step 4. The user now decides that adding the person was a mistake, and decides to undo that action by executing the undo command. The undo command will call Model#undoAddressBook(), which will shift the currentStatePointer once to the left, pointing it to the previous address book state, and restores the address book to that state.

The following sequence diagram shows how an undo operation goes through the Logic component:

Similarly, how an undo operation goes through the Model component is shown below:

The redo command calls Model#redo(), restoring the next state if available.

Step 5. The user then decides to execute the command list. Commands that do not modify the address book, such as list, will usually not call Model#commitAddressBook(), Model#undoAddressBook() or Model#redoAddressBook(). Thus, the addressBookStateList remains unchanged.

Step 6. The user executes clear, which calls Model#commitAddressBook(). Since the currentStatePointer is not pointing at the end of the addressBookStateList, all address book states after the currentStatePointer will be purged. Reason: It no longer makes sense to redo the add n/David …​ command. This is the behavior that most modern desktop applications follow.

The following activity diagram summarizes what happens when a user executes a new command:

Design considerations:

Aspect: How undo & redo executes:

• Alternative 1 (current choice): Saves the entire address book.

  • Pros: Easy to implement.
  • Cons: May have performance issues in terms of memory usage.

• Alternative 2: Individual command knows how to undo/redo by itself.

  • Pros: Will use less memory (e.g. for delete, just save the person being deleted).
  • Cons: We must ensure that the implementation of each individual command are correct.

{more aspects and alternatives to be added}

Add member feature

The add member feature allows users to add new members to the address book with their details.

The sequence diagram below illustrates the interactions within the Logic component for adding a member:

How the add command works:

1. When the user enters an add command, LogicManager passes it to AddressBookParser.
2. AddressBookParser creates an AddCommandParser to parse the command arguments.
3. AddCommandParser validates and parses all required fields (name, year, student number, email, phone, dietary requirements, role, and optional tags).
4. An AddCommand object is created and executed.
5. Before execution, the current state is committed for undo/redo functionality.
6. AddCommand checks if a person with the same student number already exists.
7. If not duplicate, the person is added to the address book.
8. The updated address book is saved to storage.

Edit member feature

The edit member feature allows users to update existing member details.

The sequence diagram below illustrates the interactions within the Logic component for editing a member:

How the edit command works:

1. When the user enters an edit command with an index and field updates, LogicManager passes it to AddressBookParser.
2. AddressBookParser creates an EditCommandParser to parse the command arguments.
3. EditCommandParser validates the index and parses the optional fields to update.
4. An EditCommand object is created with an EditPersonDescriptor containing the updates.
5. Before execution, the current state is committed for undo/redo functionality.
6. EditCommand retrieves the person at the specified index from the filtered list.
7. A new Person object is created with the updated fields.
8. EditCommand checks if the edited person already exists (unless it's the same person).
9. If valid, the person is updated in the address book.
10. The filtered list is updated to show all persons.
11. The updated address book is saved to storage.

Find member feature

The find member feature allows users to search for members by keywords across all fields.

The sequence diagram below illustrates the interactions within the Logic component for finding members:

How the find command works:

1. When the user enters a find command with keywords, LogicManager passes it to AddressBookParser.
2. AddressBookParser creates a FindCommandParser to parse the command arguments.
3. FindCommandParser splits the input into keywords.
4. A PersonContainsKeywordsPredicate is created with the keywords.
5. A FindCommand object is created and executed.
6. FindCommand updates the filtered person list with the predicate.
7. The predicate tests each person to see if their fields contain all the keywords (case-insensitive).
8. Only persons matching all keywords are shown in the filtered list.
9. The result message shows how many persons match the criteria.

Add event feature

The add event feature allows users to create new events with an event ID, date, and description.

The sequence diagram below illustrates the interactions within the Logic component for adding an event:

How the addevent command works:

1. When the user enters an addevent command, LogicManager passes it to AddressBookParser.
2. AddressBookParser creates an AddEventCommandParser to parse the command arguments.
3. AddEventCommandParser validates and parses the event ID, date, and description.
4. An AddEventCommand object is created and executed.
5. Before execution, the current state is committed for undo/redo functionality.
6. AddEventCommand checks if an event with the same ID already exists.
7. If not duplicate, the event is added to the address book.
8. The updated address book is saved to storage.

Attendance feature

The attendance feature allows users add and record which members attended specific events.

The sequence diagram below illustrates how attendance is added for an event:

The activity diagram below summarizes the flow when adding attendance:

How the attendance feature works:

1. When the user enters an addattendance command with an event ID and member names, LogicManager passes it to AddressBookParser.
2. AddressBookParser creates an AddAttendanceCommandParser to parse the command arguments.
3. An AddAttendanceCommand object is created.
4. Before execution, the current state is committed for undo/redo functionality (in LogicManager#execute()).
5. AddAttendanceCommand retrieves the event by event ID from the model.
6. For each member name, it checks if the member exists and if attendance hasn't already been recorded.
7. Duplicate entries are ignored.
8. New Attendance objects are created and added to the event.
9. A success message is built showing which members were added and which were duplicates.
10. The updated address book is saved to storage.

Other attendance related features (markattendance, unmarkattendance, removeAttendees) work in a similar way and are also undoable.

Documentation, logging, testing, configuration, dev-ops

• Documentation guide
• Testing guide
• Logging guide
• Configuration guide
• DevOps guide

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Appendix: Product Scope

Target User Profile

Primary User: CCA secretary in NUS, who needs to:

• Manage 50+ contacts of members with different roles in a structured way.
• Keep track of members’ preferences and dietary restrictions.
• Record event attendees and mark attendance.
• Delegate and track tasks.

Pain Points:

• Fragmented systems: Currently uses spreadsheets, group chats, and manual checklists, which are error-prone and time-consuming.
• Repetitive tasks: Re-entering the same member details across multiple files and attendance sheets.
• Lack of structure: Hard to filter/search members quickly (e.g., “all Year 1 members who are vegetarian”).

Value Proposition

A streamlined address book that organises member details, tracks unique preferences, and simplifies event attendance — helping secretaries stay efficient, accurate, and focused on building stronger communities.

User Stories

Priorities: High (must have) - * * *, Medium (nice to have) - * *, Low (unlikely to have) - *

Use Cases

For all use cases below, the System is ClubHub and the Actor is the Secretary, unless specified otherwise.

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Use case: UC01 – Add Member

System: ClubHub Actor: Secretary

MSS (Main Success Scenario):

1. Secretary chooses to add a member.
2. ClubHub requests name, year, role, dietary requirements, student number, phone number(above are compulsory).
3. Secretary enters the requested details.
4. ClubHub validates inputs and creates the member record.
5. ClubHub displays confirmation and the updated member list.
6. Use case ends.

Extensions:

• 3a. Missing/invalid fields.
  • 3a1. ClubHub displays an error message and usage hint.
  • 3a2. Secretary re-enters data.
  • Use case resumes from step 4.
  • Use case ends.

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Use case: UC02 – Search Members by Field

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to search members.
2. ClubHub requests search criteria (e.g., field and query).
3. Secretary enters the field and query (e.g., Field: Year, Query: 3).
4. ClubHub searches members whose specified field matches the query.
5. ClubHub displays a list of matching members with key details (e.g., Name, Year, Role, Dietary Restriction).
6. (Optional) Secretary selects a member to view full details.
7. Use case ends.

Extensions:

• 2a. Secretary omits field or query.
  • 2a1. ClubHub prompts for the missing input(s).
  • Use case resumes from step 3.
• 3a. Invalid field name provided.
  • 3a1. ClubHub lists supported fields.
  • 3a2. Secretary re-enters a valid field.
  • Use case resumes from step 3.
• 4a. No members match the criteria.
  • 4a1. ClubHub displays an error message and suggests refining the query.
  • Use case ends.
• 5a. Result set is too large.
  • 5a1. ClubHub paginates results or prompts for filters.
  • Use case resumes from step 3 or continues browsing.
• *a. At any time, Secretary cancels.
  • *a1. ClubHub asks to confirm cancellation.
  • *a2. Secretary confirms.
  • Use case ends.

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Use case: UC03 – Create Event

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to create an event.
2. ClubHub requests event ID, date, and description.
3. Secretary enters details.
4. ClubHub validates and creates the event.
5. ClubHub displays confirmation.
6. Use case ends.

Extensions:

• 3a. Duplicate/non-conforming EventID or invalid date/description.
  • 3a1. ClubHub displays an error message.
  • 3a2. Secretary re-enters data.
  • Use case resumes from step 4.

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Use case: UC04 – Record Event Attendance

System: ClubHub Actor: Secretary

MSS:

1. Secretary searches for an event by ID.
2. ClubHub displays the event details.
3. Secretary chooses to record attendance.
4. ClubHub displays the list of members.
5. Secretary marks members as attended.
6. ClubHub saves the attendance and confirms.
7. Use case ends.

Extensions:

• 1a. Event not found.
  • 1a1. ClubHub displays an error message.
  • Use case ends.
• 5a. Secretary marks the same member again.
  • 5a1. ClubHub ignores duplicate and continues.

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Use case: UC05 – Update Member Details

System: ClubHub Actor: Secretary

MSS:

1. Secretary searches for the member by name and year.
2. ClubHub displays the member’s current details.
3. Secretary chooses to edit details.
4. ClubHub requests updated information.
5. Secretary enters new details (e.g., role changed).
6. ClubHub validates and updates the record.
7. ClubHub confirms the update.
8. Use case ends.

Extensions:

• 1a. No member matches the search.
  • 1a1. ClubHub displays an error message.
  • Use case ends.
• 6a. Invalid details entered.
  • 6a1. ClubHub requests correction.
  • 6a2. Secretary re-enters details.
  • Use case resumes from step 7.

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Use case: UC06 – Undo Last Action

System: ClubHub Actor: Secretary

MSS:

1. Secretary issues the undo command.
2. ClubHub restores the system to its state before the last action.
3. ClubHub displays confirmation.
4. Use case ends.

Extensions:

• 1a. No action available to undo.
  • 1a1. ClubHub displays an error message.
  • Use case ends.

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Use case: UC07 – View Attendance

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to view attendance for an event.
2. ClubHub displays the list of members who attended and those who absent.
3. Secretary identifies absentees for follow-up actions.
4. Use case ends.

Extensions:

• 1a. Event not found.
  • 1a1. ClubHub displays an error message.
  • Use case ends.
• 2a. No attendance recorded yet.
  • 2a1. ClubHub displays an error message.
  • Use case ends.

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Use case: UC08 – Delete Event

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to delete an event.
2. ClubHub requests event ID and confirmation.
3. Secretary provides the ID and confirms deletion.
4. ClubHub deletes the event and shows success message.
5. Use case ends.

Extensions:

• 2a. Event not found.
  • 2a1. ClubHub displays an error message.
  • Use case ends.

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Use case: UC9 – Bulk Import/Export Member Details

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to import or export member details.
2. For import:
   • ClubHub requests a CSV/Excel file.
   • Secretary uploads the file.
   • ClubHub validates the file format and contents.
   • ClubHub imports member data and shows summary of new/updated records.
3. For export:
   • ClubHub generates a CSV/Excel file with current member details.
   • Secretary downloads the file.
4. Use case ends.

Extensions:

• 2a. Import file invalid (wrong format, missing fields).
  • 2a1. ClubHub displays an error message.
  • 2a2. Secretary corrects file and retries.
• 2b. Duplicate entries in import file.
  • 2b1. ClubHub informs user that the malformed line has been skipped.
  • Use case resumes from step 2.

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Use case: UC10 – Manage Budget

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to manage the club’s budget.
2. ClubHub prompts for budget amount, start date, and end date.
3. Secretary enters the amount and date range.
4. ClubHub validates the inputs.
5. ClubHub saves the budget and displays confirmation with budget details.
6. Secretary requests to view the budget report.
7. ClubHub retrieves expenses within the budget period.
8. ClubHub displays total budget, total spent, remaining balance, and expenses per event.
9. Secretary requests to reset the budget.
10. ClubHub prompts for confirmation.
11. Secretary confirms the reset action.
12. ClubHub clears the budget and shows a success message.
13. Use case ends.

Extensions:

• 4a. Inputs are invalid (negative amount or invalid date range).
  • 4a1. ClubHub displays an error message.
  • 4a2. Secretary corrects the inputs and retries from step 3.
• 4b. Entered budget period overlaps an existing budget.
  • 4b1. ClubHub prompts for confirmation to overwrite.
  • 4b2. Secretary confirms overwrite; use case resumes from step 5.
• 7a. No expenses recorded in the budget period.
  • 7a1. ClubHub displays zero spending in the report.
  • Use case resumes at step 8.
• 8a. No budget set when the report is requested.
  • 8a1. ClubHub displays an error message.
  • Use case ends.

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Use case: UC11 – Add Task to Task List

System: ClubHub Actor: Secretary

MSS:

1. Secretary chooses to add a new task.
2. ClubHub prompts for the task title and optional deadline.
3. Secretary enters the task details.
4. ClubHub validates the details.
5. ClubHub adds the task to the list and displays the confirmation with task details.
6. Use case ends.

Extensions:

• 4a. Task already exists.
  • 4a1. ClubHub displays an error message.
  • 4a2. Secretary modifies the details and retries from step 3.
• 4b. Deadline format is invalid.
  • 4b1. ClubHub displays an error message.
  • 4b2. Secretary corrects the deadline and retries from step 3.

Non-Functional Requirements

• Performance: Actions (add/search/edit) should respond within 1 second for up to 200 members.
• Usability: Must be usable via CLI with clear error messages and undo support.
• Portability: Runs locally on Windows, macOS, and Linux.
• Single-user: Only one secretary per copy of the app.
• No remote server: All data stored locally.
• Reliability: Data should not be lost when the program closes.
• Incremental development: Feature additions should not break previous functionality.
• Security: User data should not be exposed externally.

Glossary

Actor An entity (usually a user or external system) that interacts with ClubHub. In most use cases, the actor is the Secretary, though other Exco members may also interact with the system.

Attendance A record of which members were present at an event. Used to generate statistics and track participation.

ClubHub The system being developed to support secretarial duties, including member management, event organisation, task assignment, and record-keeping.

Dietary Restriction Any limitation on food or drink that a member cannot consume (e.g., vegetarian, halal, no seafood). Stored in member records to aid event meal planning.

Event A scheduled club activity created and tracked in ClubHub. Each event has an ID, date, and description, and may include attendance records.

Exco (Executive Committee) The group of members responsible for running the club (e.g., President, Treasurer, Secretary). Exco members may have special access privileges.

Field A specific attribute of a member record (e.g., Name, Year, Role, Dietary Restriction) used for searching and filtering.

Member A registered individual in ClubHub with stored details such as name, year of study, role, student number, phone number, and optional telegram handle.

Member Record The collection of data fields stored for a member in ClubHub.

Role The position a member holds in the club (e.g., President, Treasurer, Secretary, General Member).

Secretary The main user of ClubHub. Responsible for managing members, creating events, tracking attendance, assigning tasks, and maintaining records.

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Appendix: Instructions for manual testing

Given below are instructions to test the app manually.

Launch and shutdown

1. Initial launch

   1. Download the jar file and copy into an empty folder

   2. Double-click the jar file Expected: Shows the GUI with a set of sample contacts. The window size may not be optimum.

2. Saving window preferences

   1. Resize the window to an optimum size. Move the window to a different location. Close the window.

   2. Re-launch the app by double-clicking the jar file.
      Expected: The most recent window size and location is retained.

Adding a member

1. Adding a member with all fields

   1. Test case: add n/John Doe y/3 s/A1234567X e/johnd@example.com p/98765432 d/Vegetarian r/President t/leadership
      Expected: New member is added to the list. Success message shows the member's details. Member appears in the person list panel.

   2. Test case: add n/John Doe y/3 s/A1234567X e/johnd@example.com p/98765432 d/Vegetarian r/President (without tags)
      Expected: Member is added successfully without tags.

   3. Test case: Missing required fields (e.g., add n/John Doe)
      Expected: Error message shown indicating missing required fields.

   4. Test case: Duplicate student number
      Expected: Error message indicating that a person with this student number already exists.

Editing a member

1. Editing a member

   1. Prerequisites: List all members using the list command. Multiple members in the list.

   2. Test case: edit 1 p/91234567 e/johndoe@example.com
      Expected: Phone number and email of the first member are updated. Success message shows the updated member's details.

   3. Test case: edit 1 t/ (clear tags)
      Expected: All tags of the first member are removed.

   4. Test case: edit 0
      Expected: Error message indicating invalid index.

Finding members

1. Finding members by keywords

   1. Test case: find john
      Expected: All members with "john" in their name or attributes are listed. Case-insensitive matching.

   2. Test case: find vegetarian year 2
      Expected: Members who are both vegetarian and in year 2 are shown.

   3. Test case: find xyz123 (no matches)
      Expected: Message indicating no members found. Empty list displayed.

Deleting a member

1. Deleting a member while all members are being shown

   1. Prerequisites: List all members using the list command. Multiple members in the list.

   2. Test case: delete 1
      Expected: First member is deleted from the list. Details of the deleted member shown in the status message. Timestamp in the status bar is updated.

   3. Test case: delete 0
      Expected: No member is deleted. Error details shown in the status message.

   4. Other incorrect delete commands to try: delete, delete x, ... (where x is larger than the list size)
      Expected: Error message shown.

Events

1. Adding an event

   1. Test case: addevent e/Orientation2025 dt/2025-08-15 desc/NUS Freshmen Orientation
      Expected: New event is added to the event list. Success message confirms event creation.

   2. Test case: Duplicate event ID
      Expected: Error message indicating that an event with this ID already exists.

   3. Test case: Invalid date format
      Expected: Error message indicating invalid date format.

2. Deleting an event

   1. Prerequisites: At least one event exists.

   2. Test case: deleteevent e/Orientation2025
      Expected: Event with ID "Orientation2025" is deleted. Success message confirms deletion.

   3. Test case: deleteevent e/NonExistentEvent
      Expected: Error message indicating event not found.

Attendance

1. Adding attendance

   1. Prerequisites: At least one event and one member exist.

   2. Test case: addattendance e/Orientation2025 m/John Doe
      Expected: John Doe is added to the attendance list for Orientation2025. Success message confirms addition.

   3. Test case: Adding the same member twice
      Expected: Duplicate is ignored. Success message indicates which members were added and which were duplicates.

   4. Test case: Adding attendance for non-existent event
      Expected: Error message indicating event not found.

2. Marking attendance

   1. Prerequisites: Member has been added to attendance list using addattendance.

   2. Test case: markattendance e/Orientation2025 m/John Doe
      Expected: John Doe is marked as attended. Success message confirms marking.

   3. Test case: Marking already marked member
      Expected: Message indicates member was already marked. No error occurs.

3. Viewing attendees

   1. Prerequisites: At least one event with attendees exists.

   2. Test case: viewattendees e/Orientation2025
      Expected: List of all attendees for the event is displayed with their attendance status.

4. Showing attendance summary

   1. Test case: showattendance e/Orientation2025
      Expected: Summary showing counts of attended and absent members is displayed.

Tasks

1. Adding a task

   1. Test case: addtask Submit budget report dl/2025-11-01 23:59
      Expected: New task is added to the task list. Success message shows task details with deadline.

   2. Test case: addtask Buy supplies (without deadline)
      Expected: Task is added without a deadline.

2. Marking a task

   1. Prerequisites: At least one task exists.

   2. Test case: marktask 1
      Expected: First task is marked as done. Task status updates in the UI.

3. Unmarking a task

   1. Prerequisites: At least one completed task exists.

   2. Test case: unmarktask 1
      Expected: First task is unmarked (marked as not done). Task status updates in the UI.

4. Deleting a task

   1. Test case: deletetask 1
      Expected: First task is deleted from the list. Success message confirms deletion.

Budget and expenses

1. Setting a budget

   1. Test case: budgetset a/1000.00 from/2025-01-01 to/2025-12-31
      Expected: Budget is set successfully. Success message confirms budget details.

   2. Test case: Negative amount or invalid date range
      Expected: Error message indicating invalid input.

2. Setting event expense

   1. Prerequisites: At least one event exists.

   2. Test case: setexpense 1 a/150.00
      Expected: Expense for the first event is set to $150.00. Expense appears beside the event title in the event list panel.

   3. Test case: setexpense 1 a/-50.00 (negative amount)
      Expected: Error message indicating amount cannot be negative.

   4. Test case: setexpense 1 a/150.555 (more than 2 decimal places)
      Expected: Error message indicating amount must have at most 2 decimal places.

3. Budget report

   1. Prerequisites: A budget has been set and at least one event exists.

   2. Test case: budgetreport
      Expected: Report showing total budget, total spent, remaining balance, and expenses per event is displayed.

4. Resetting budget

   1. Test case: budgetreset
      Expected: Budget is cleared. Success message confirms reset.

Undo and redo

1. Undoing a command

   1. Prerequisites: At least one command that modifies data has been executed (e.g., add, edit, delete).

   2. Test case: add n/Test Person y/2 s/T1234567A e/test@example.com p/12345678 d/None r/Member followed by undo
      Expected: The added member is removed. System returns to state before the add command.

   3. Test case: undo when no commands to undo
      Expected: Error message indicating no commands to undo.

2. Redoing a command

   1. Prerequisites: At least one undo command has been executed.

   2. Test case: undo followed by redo
      Expected: The undone command is reapplied. System returns to state after the original command.

   3. Test case: redo when no commands to redo
      Expected: Error message indicating no commands to redo.

3. Undo/Redo with multiple commands

   1. Test case: Execute multiple modifying commands (add, edit, delete), then undo multiple times
      Expected: Each undo reverts one command in reverse order.

Import and export

1. Exporting members

   1. Prerequisites: At least one member exists.

   2. Test case: export /to members.csv
      Expected: CSV file is created with all member data. Success message confirms export.

2. Importing members

   1. Prerequisites: A valid CSV file exists with member data.

   2. Test case: import /from members.csv
      Expected: Members from CSV file are imported. Success message shows import summary.

   3. Test case: Import file with invalid format
      Expected: Error message indicating file format issues.

Saving data

1. Test case: Missing data file

   1. Close the app.

   2. Navigate to your project’s data/ folder and delete addressbook.json.

   3. Re-launch the app by double-clicking the JAR file.
      Expected: The app starts successfully with an empty member list.
      No crash or error message appears.
      Upon adding a new member or closing the app, a new valid addressbook.json file is created automatically.

2. Test case: Corrupted data file

   1. Close the app.

   2. Navigate to your project’s data/ folder and open addressbook.json in a text editor.

   3. Delete or modify part of the file (e.g. remove a closing brace } or change a field name). Save and close the file.

   4. Re-launch the app by double-clicking the JAR file.
      Expected: The app displays a warning in the logs:
      "Data file not in the correct format. Starting with an empty AddressBook."
      The UI shows an empty list of members.
      On exit, the corrupted file is replaced with a new, valid empty JSON file.