Merge pull request #164 from AY1920S1-CS2103-T14-4/New_Add_Budget

Update Dg

docs/DeveloperGuide.adoc

@@ -126,12 +126,6 @@ The `Model`,
 * stores an `ExchangeData` object that represents the foreign exchange rates for conversion of currencies.
 * stores the MYMorise data.
 * exposes an unmodifiable `ObservableList<Expense>` and an unmodifiable `ObservableList<Budget>` that can be 'observed' e.g. the UI can be bound to either list so that the UI automatically updates when the data in the list change.
-* does not depend on any of the other three components.
-
-[NOTE]
-As a more OOP model, we can store a `Tag` list in `Address Book`, which `Person` can reference. This would allow `Address Book` to only require one `Tag` object per unique `Tag`, instead of each `Person` needing their own `Tag` object. An example of how such a model may look like is given below. +
- +
-image:BetterModelClassDiagram.png[]
 
 [[Design-Storage]]
 === Storage component
@@ -155,6 +149,69 @@ Classes used by multiple components are in the `seedu.addressbook.commons` packa
 
 This section describes some noteworthy details on how certain features are implemented.
 
+=== Budget Feature
+==== Overview
+The Budget feature allows users to track their expenses in relation to the budget set. Expenses created by the user after a budget is set and falls into a budget period will
+automatically be added into that budget.
+
+The feature allows the user to view a list of all the budgets created in the app. From the list of budgets, users may view any specific budget
+showing all the expenses allocated into the budget, along with the amount left in the budget.
+Users may add, delete, edit a budget as well as the expenses inside the budget.
+
+==== Implementation
+The `BudgetList` stores all the budgets created in the App. To facilitate the adding, deleting and editing of budgets, the BudgetList provides a
+few operations such as: +
+`BudgetList#addBudget(budget)` - Add a new budget into the list of budgets in the budget list. +
+`BudgetList#setBudget(budget, editedBudget)` - Edit a current existing budget to a different budget +
+`BudgetList#removeBudget(budget)` - Remove a specified budget
+
+Given below is an activity diagram to show how a budget is added.
+
+image::AddBudgetActivityDiagram.png[]
+
+Given below is an activity diagram to show how an expense is added after the implementation of budget.
+
+image::AddExpenseActivityDiagram.png[]
+
+Given below is a class diagram of a Budget.
+
+image::BudgetClassDiagram.png[]
+
+Notice that the budget consists of 2 Amounts and 2 Dates. +
+The 2 Amounts refer to the Budget Amount set by the user and the Budget Amount
+currently left after deducting all expenses in the budget. +
+The 2 Dates refer to the Start Date of the Budget and the End Date of the budget. All expenses added after the budget is created,
+and fall within this 2 dates, will be automatically added into the budget.
+
+Given below is an example of a object diagram of a newly created Budget.
+
+image::BudgetObjectDiagram.png[]
+
+The Budget consists of an ExpenseList which holds all expenses added into the Budget.
+
+==== Design Consideration
+There were 2 main design choices we had to choose from for the implementation of the Budget Feature. +
+
+*Aspect: A single source of truth* +
+The model consists of an expense list and a budget list.
+
+- *Alternative 1:* Have a master expense list to store all expenses created and a budget list that consist of an internal
+expense list that stores copies of the expenses from master expense list that fall into the budget. In this option, commands that affect expenses, will require
+an update in the master expense list and the expense lists inside budgets affected. +
+    * Pros: Easy to implement, easy to keep track of a overall expenses.
+    * Cons: Multiple objects of the same expense. An update to an expense in the overall expense list will require a same update
+            to the same expense located in the budget. May result in bugs when commands affect expenses.
+
+- *Alternative 2:* Have a default expense list that stores only expenses that do not fall into a budget, and a budget list that consist
+of an internal expense list that stores the expenses that fall into a budget when the expense is added or edited. In this option, there is only
+1 copy of any expense created by the user. Any edit or delete of an expense affects directly to the original expense object.
+    * Pros: Achieve a single source of truth. Does not introduce possible bugs that may be present if there were multiple copies of the same expense.
+    * Cons: More complex to implement. In order to view all expenses in the app, the program will have to loop through the default expense list
+            and the expense lists of every single budget.
+
+*Alternative 2* was chosen. Reason is because a single source of truth would eliminate duplicate entries of the same data. This would
+also reduce the possibility of bugs that may come with duplicate entries.
+
 === AutoComplete Feature
 ==== Implementation
 Autocomplete is facilitated by several parts.

docs/diagrams/AddBudgetActivityDiagram.puml

@@ -0,0 +1,18 @@
+@startuml
+start
+:User executes AddExpense command;
+'diamond
+if () then ([budget does not exist])
+    'diamond
+    if () then ([budget period doesn't clash with existing budgets])
+        : add budget into the budget list;
+        : Update UI;
+        : Save default expense list and budget list;
+    else ([else])
+        : user receives budget clash message;
+    endif
+else ([else])
+    : user receives budget duplicate message;
+endif
+stop
+@enduml

docs/diagrams/AddExpenseActivityDiagram.puml

@@ -0,0 +1,21 @@
+@startuml
+start
+:User executes AddExpense command;
+
+'diamond
+if () then ([expense does not exist])
+    'diamond
+    if () then ([expense falls into a budget period])
+        : get budget which expense falls into;
+        : add expense into the budget;
+
+    else ([else])
+        : add expense into default expense list;
+    endif
+        :Update UI;
+        :Save default expense list and budget list;
+else ([else])
+    : user receives expense duplicate message;
+endif
+stop
+@enduml

docs/diagrams/ArchitectureSequenceDiagram.puml

@@ -13,11 +13,24 @@ activate ui UI_COLOR
 ui -[UI_COLOR]> logic : execute("delete 1")
 activate logic LOGIC_COLOR
 
-logic -[LOGIC_COLOR]> model : deleteExpense(e)
+logic -[LOGIC_COLOR]> model : getViewState()
+activate model MODEL_COLOR
+model -[MODEL_COLOR]-> logic
+deactivate model
+
+alt BudgetList
+logic -[LOGIC_COLOR]> model : deleteBudget(b)
 activate model MODEL_COLOR
+model -[MODEL_COLOR]-> logic
+deactivate model
 
+else ExpenseList
+logic -[LOGIC_COLOR]> model : deleteExpense(e)
+activate model MODEL_COLOR
 model -[MODEL_COLOR]-> logic
 deactivate model
+end
+
 
 logic -[LOGIC_COLOR]> storage : saveMymorise()
 activate storage STORAGE_COLOR

docs/diagrams/BudgetClassDiagram.puml

@@ -0,0 +1,23 @@
+@startuml
+!include style.puml
+skinparam arrowThickness 1.1
+skinparam arrowColor MODEL_COLOR
+skinparam classBackgroundColor MODEL_COLOR
+
+Class Budget
+Class Amount
+Class Currency
+Class Date
+Class Name
+Class ExpenseList
+
+Budget *--> "1" Name
+Budget *--> "2" Amount
+Budget *--> "2" Date
+Budget *--> "1" Currency
+Budget *--> "1" ExpenseList
+
+Name -[hidden]right-> Amount
+Amount -[hidden]right-> Date
+
+@enduml

docs/diagrams/BudgetObjectDiagram.puml

@@ -0,0 +1,30 @@
+@startuml
+object ":Budget" as o
+object "name:Name" as o2
+object "currency:Currency" as o3
+object "startDate:Date" as o4
+object "endDate:Date" as o5
+object "amount:Amount" as o6
+object "amountLeft:Amount" as o7
+object "expenseList:ExpenseList" as o8
+object "expenses:UniqueExpenseList" as o9
+
+
+o2 : fullName = "Japan Travel"
+o3 : name = "JPY"
+o4 : value = "12 Dec 2019"
+o5 : value = "18 Dec 2019"
+o6 : value = "9500"
+o7 : value = "9500"
+
+o --> o2
+o --> o3
+o --> o4
+o --> o5
+o --> o6
+o --> o7
+o --> o8
+o8 --> o9
+
+
+@enduml

docs/diagrams/DeleteSequenceDiagram.puml

@@ -48,8 +48,23 @@ deactivate MymParser
 LogicManager -> DeleteCommand : execute()
 activate DeleteCommand
 
-DeleteCommand -> Model : deleteExpense(1)
+DeleteCommand -> Model : getViewState()
 activate Model
+Model --> DeleteCommand
+deactivate Model
+
+alt BudgetList
+DeleteCommand -> Model : deleteBudget(b)
+activate Model
+Model --> DeleteCommand
+deactivate Model
+
+else ExpenseList
+DeleteCommand -> Model : deleteExpense(e)
+activate Model
+Model --> DeleteCommand
+deactivate Model
+end
 
 Model --> DeleteCommand
 deactivate Model

src/main/java/seedu/address/ui/MainWindow.java

@@ -225,7 +225,6 @@ private CommandResult executeCommand(String commandText) throws CommandException
             expenseListPanel = new ExpenseListPanel(logic.updateExpenses());
             //Update Left panel with all expenses.
             leftListPanelPlaceHolder.getChildren().add(expenseListPanel.getRoot());
-            //            statsDisplayPlaceHolder.getChildren().add(statsDisplay.getRoot());
 
             if (commandResult.isShowHelp()) {
                 handleHelp();