Merge pull request #132 from yican95/feature/discount-item

v1.3 discount-item

src/main/java/seedu/address/logic/commands/menu/AddItemCommand.java

@@ -15,7 +15,7 @@
 import seedu.address.model.menu.Item;
 
 /**
- * Adds an item to the address book.
+ * Adds an item to the menu.
  */
 public class AddItemCommand extends Command {
 

src/main/java/seedu/address/logic/commands/menu/DiscountItemCommand.java

@@ -0,0 +1,94 @@
+package seedu.address.logic.commands.menu;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_PERCENT;
+import static seedu.address.model.Model.PREDICATE_SHOW_ALL_ITEMS;
+
+import java.util.List;
+
+import seedu.address.commons.core.EventsCenter;
+import seedu.address.commons.core.Messages;
+import seedu.address.commons.core.index.Index;
+import seedu.address.commons.events.ui.DisplayItemListRequestEvent;
+import seedu.address.logic.CommandHistory;
+import seedu.address.logic.commands.Command;
+import seedu.address.logic.commands.CommandResult;
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+import seedu.address.model.menu.Item;
+import seedu.address.model.menu.Price;
+
+/**
+ * Gives an existing item in the menu a discount.
+ */
+public class DiscountItemCommand extends Command {
+
+    public static final String COMMAND_WORD = "discount-item";
+
+    public static final String COMMAND_ALIAS = "dci";
+
+    public static final String MESSAGE_USAGE = COMMAND_WORD + ": Gives the item identified "
+            + "by the index number used in the displayed item list a discount based on the percent. "
+            + "Existing values will be overwritten by the input values.\n"
+            + "Parameters: INDEX (must be a positive integer) "
+            + "[" + PREFIX_PERCENT + "PRICE] "
+            + "Example: " + COMMAND_WORD + " 1 "
+            + PREFIX_PERCENT + "20";
+
+    public static final String MESSAGE_DISCOUNT_ITEM_SUCCESS = "Discounted Item: %1$s";
+
+    private final Index index;
+    private final double percent;
+
+    /**
+     * @param index of the item in the filtered item list to edit
+     * @param percent the percent of the discount
+     */
+    public DiscountItemCommand(Index index, double percent) {
+        requireNonNull(index);
+        requireNonNull(percent);
+
+        this.index = index;
+        this.percent = percent;
+    }
+
+    @Override
+    public CommandResult execute(Model model, CommandHistory history) throws CommandException {
+        requireNonNull(model);
+        List<Item> lastShownList = model.getFilteredItemList();
+
+        if (index.getZeroBased() >= lastShownList.size()) {
+            throw new CommandException(Messages.MESSAGE_INVALID_ITEM_DISPLAYED_INDEX);
+        }
+
+        Item itemToDiscount = lastShownList.get(index.getZeroBased());
+        Item discountedItem = createDiscountedItem(itemToDiscount, percent);
+
+        model.updateItem(itemToDiscount, discountedItem);
+        model.updateFilteredItemList(PREDICATE_SHOW_ALL_ITEMS);
+        model.commitAddressBook();
+        EventsCenter.getInstance().post(new DisplayItemListRequestEvent());
+        return new CommandResult(String.format(MESSAGE_DISCOUNT_ITEM_SUCCESS, discountedItem));
+    }
+
+    /**
+     * Creates and returns a {@code Item} with the details of {@code itemToEdit}
+     * edited with {@code editItemDescriptor}.
+     */
+    public static Item createDiscountedItem(Item itemToEdit, double percent) {
+        assert itemToEdit != null;
+        double originalValue = itemToEdit.getPrice().getOriginalValue();
+        Price updatedPrice = new Price(String.format("%.2f", originalValue));
+        updatedPrice.setValue(percent);
+
+        return new Item(itemToEdit.getName(), updatedPrice, itemToEdit.getRemark(), itemToEdit.getTags());
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        return other == this // short circuit if same object
+                || (other instanceof DiscountItemCommand // instanceof handles nulls
+                    && index.equals(((DiscountItemCommand) other).index) // state check
+                    && percent == ((DiscountItemCommand) other).percent); // state check
+    }
+}

src/main/java/seedu/address/logic/parser/AddressBookParser.java

@@ -31,6 +31,7 @@
 import seedu.address.logic.commands.menu.AddItemCommand;
 import seedu.address.logic.commands.menu.ClearMenuCommand;
 import seedu.address.logic.commands.menu.DeleteItemCommand;
+import seedu.address.logic.commands.menu.DiscountItemCommand;
 import seedu.address.logic.commands.menu.EditItemCommand;
 import seedu.address.logic.commands.menu.FilterMenuCommand;
 import seedu.address.logic.commands.menu.FindItemCommand;
@@ -54,6 +55,7 @@
 import seedu.address.logic.parser.ingredients.EditIngredientCommandParser;
 import seedu.address.logic.parser.menu.AddItemCommandParser;
 import seedu.address.logic.parser.menu.DeleteItemCommandParser;
+import seedu.address.logic.parser.menu.DiscountItemCommandParser;
 import seedu.address.logic.parser.menu.EditItemCommandParser;
 import seedu.address.logic.parser.menu.FilterMenuCommandParser;
 import seedu.address.logic.parser.menu.FindItemCommandParser;
@@ -224,6 +226,10 @@ public Command parseCommand(String userInput) throws ParseException {
         case TodaySpecialCommand.COMMAND_ALIAS:
             return new TodaySpecialCommand();
 
+        case DiscountItemCommand.COMMAND_WORD:
+        case DiscountItemCommand.COMMAND_ALIAS:
+            return new DiscountItemCommandParser().parse(arguments);
+
         case ClearMenuCommand.COMMAND_WORD:
         case ClearMenuCommand.COMMAND_ALIAS:
             return new ClearMenuCommand();

src/main/java/seedu/address/logic/parser/CliSyntax.java

@@ -31,6 +31,7 @@ public class CliSyntax {
 
     /*Prefix definitions for menu management */
     public static final Prefix PREFIX_PRICE = new Prefix("p/");
+    public static final Prefix PREFIX_PERCENT = new Prefix("dp/");
 
     /*Prefix definitions for reservation management */
     public static final Prefix PREFIX_PAX = new Prefix("px/");

src/main/java/seedu/address/logic/parser/menu/DiscountItemCommandParser.java

@@ -0,0 +1,60 @@
+package seedu.address.logic.parser.menu;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.commons.core.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_PERCENT;
+
+import seedu.address.commons.core.index.Index;
+import seedu.address.logic.commands.menu.DiscountItemCommand;
+import seedu.address.logic.parser.ArgumentMultimap;
+import seedu.address.logic.parser.ArgumentTokenizer;
+import seedu.address.logic.parser.Parser;
+import seedu.address.logic.parser.ParserUtil;
+import seedu.address.logic.parser.exceptions.ParseException;
+
+/**
+ * Parses input arguments and creates a new DiscountItemCommand object
+ */
+public class DiscountItemCommandParser implements Parser<DiscountItemCommand> {
+    public static final String MESSAGE_PERCENT_CONSTRAINTS =
+            "Percent should only contain numbers, and it should be at most 2 digits";
+    public static final String PERCENT_VALIDATION_REGEX = "\\d{0,2}";
+
+    /**
+     * Parses the given {@code String} of arguments in the context of the DiscountItemCommand
+     * and returns an DiscountItemCommand object for execution.
+     * @throws ParseException if the user input does not conform the expected format
+     */
+    public DiscountItemCommand parse(String args) throws ParseException {
+        requireNonNull(args);
+        ArgumentMultimap argMultimap = ArgumentTokenizer.tokenize(args, PREFIX_PERCENT);
+
+        Index index;
+
+        try {
+            index = ParserUtil.parseIndex(argMultimap.getPreamble());
+        } catch (ParseException pe) {
+            throw new ParseException(String.format(MESSAGE_INVALID_COMMAND_FORMAT, DiscountItemCommand.MESSAGE_USAGE),
+                    pe);
+        }
+
+        if (!argMultimap.getValue(PREFIX_PERCENT).isPresent()) {
+            throw new ParseException(String.format(MESSAGE_INVALID_COMMAND_FORMAT, DiscountItemCommand.MESSAGE_USAGE));
+        }
+        String trimmedPercent = argMultimap.getValue(PREFIX_PERCENT).get().trim();
+        if (!isValidPercent(trimmedPercent)) {
+            throw new ParseException(MESSAGE_PERCENT_CONSTRAINTS);
+        }
+        double percent = Double.parseDouble(trimmedPercent);
+
+        return new DiscountItemCommand(index, percent);
+    }
+
+    /**
+     * Returns true if a given string is a valid percent.
+     */
+    private static boolean isValidPercent(String test) {
+        return test.matches(PERCENT_VALIDATION_REGEX);
+    }
+
+}

src/main/java/seedu/address/logic/parser/menu/SortMenuCommandParser.java

@@ -9,7 +9,7 @@
 import seedu.address.logic.parser.exceptions.ParseException;
 
 /**
- * Parses input arguments and creates a new FindItemCommand object
+ * Parses input arguments and creates a new SortMenuCommand object
  */
 public class SortMenuCommandParser implements Parser<SortMenuCommand> {
 

src/main/java/seedu/address/model/menu/Item.java

@@ -55,8 +55,8 @@ public Set<Tag> getTags() {
     }
 
     /**
-     * Returns true if both persons of the same name have at least one other identity field that is the same.
-     * This defines a weaker notion of equality between two persons.
+     * Returns true if both items of the same name have at least one other identity field that is the same.
+     * This defines a weaker notion of equality between two items.
      */
     public boolean isSameItem(Item otherItem) {
         if (otherItem == this) {

src/main/java/seedu/address/model/menu/Price.java

@@ -13,7 +13,9 @@ public class Price {
             "Price should only contain numbers, and it should be at most 2 decimal place";
     private static final String DECIMAL_PLACE_REGEX = "\\d{0,2}";
     public static final String PRICE_VALIDATION_REGEX = "\\d+" + ".?" + DECIMAL_PLACE_REGEX;
-    private final double value;
+    private static final double MAX_PERCENT = 100.0;
+    private double value;
+    private final double originalValue;
 
     /**
      * Constructs a {@code Price}.
@@ -23,6 +25,19 @@ public class Price {
     public Price(String price) {
         requireNonNull(price);
         checkArgument(isValidPrice(price), MESSAGE_PRICE_CONSTRAINTS);
+        originalValue = Double.parseDouble(price);
+        value = Double.parseDouble(price);
+    }
+
+    /**
+     * Constructs a {@code Price}.
+     *
+     * @param price A valid price.
+     */
+    public Price(String price, String originalPrice) {
+        requireNonNull(price);
+        checkArgument(isValidPrice(price), MESSAGE_PRICE_CONSTRAINTS);
+        originalValue = Double.parseDouble(originalPrice);
         value = Double.parseDouble(price);
     }
 
@@ -37,6 +52,14 @@ public double getValue() {
         return value;
     }
 
+    public double getOriginalValue() {
+        return originalValue;
+    }
+
+    public void setValue(double percent) {
+        value = originalValue * ((MAX_PERCENT - percent) / MAX_PERCENT);
+    }
+
     @Override
     public String toString() {
         //return valueInString;
@@ -47,7 +70,8 @@ public String toString() {
     public boolean equals(Object other) {
         return other == this // short circuit if same object
                 || (other instanceof Price // instanceof handles nulls
-                    && value == ((Price) other).value); // state check
+                    && value == ((Price) other).value // state check
+                    && originalValue == ((Price) other).originalValue);
     }
 
     @Override

src/main/java/seedu/address/storage/elements/XmlAdaptedItem.java

@@ -18,7 +18,7 @@
 import seedu.address.storage.XmlAdaptedTag;
 
 /**
- * JAXB-friendly version of the Person.
+ * JAXB-friendly version of the Item.
  */
 public class XmlAdaptedItem {
 
@@ -29,6 +29,8 @@ public class XmlAdaptedItem {
     @XmlElement(required = true)
     private String price;
     @XmlElement(required = true)
+    private String originalPrice;
+    @XmlElement(required = true)
     private String remark;
 
     @XmlElement
@@ -46,6 +48,7 @@ public XmlAdaptedItem() {}
     public XmlAdaptedItem(String name, String price, String remark, List<XmlAdaptedTag> tagged) {
         this.name = name;
         this.price = price;
+        this.originalPrice = price;
         this.remark = remark;
         if (tagged != null) {
             this.tagged = new ArrayList<>(tagged);
@@ -60,6 +63,7 @@ public XmlAdaptedItem(String name, String price, String remark, List<XmlAdaptedT
     public XmlAdaptedItem(Item source) {
         name = source.getName().toString();
         price = source.getPrice().toString();
+        originalPrice = String.format("%.2f", source.getPrice().getOriginalValue());
         remark = source.getRemark().toString();
         tagged = source.getTags().stream()
                 .map(XmlAdaptedTag::new)
@@ -91,7 +95,13 @@ public Item toModelType() throws IllegalValueException {
         if (!Price.isValidPrice(price)) {
             throw new IllegalValueException(Price.MESSAGE_PRICE_CONSTRAINTS);
         }
-        final Price modelPrice = new Price(price);
+        if (originalPrice == null) {
+            throw new IllegalValueException(String.format(MISSING_FIELD_MESSAGE_FORMAT, Price.class.getSimpleName()));
+        }
+        if (!Price.isValidPrice(originalPrice)) {
+            throw new IllegalValueException(Price.MESSAGE_PRICE_CONSTRAINTS);
+        }
+        final Price modelPrice = new Price(price, originalPrice);
 
         if (remark == null) {
             throw new IllegalValueException(String.format(MISSING_FIELD_MESSAGE_FORMAT, Remark.class.getSimpleName()));
@@ -115,6 +125,7 @@ public boolean equals(Object other) {
         XmlAdaptedItem otherItem = (XmlAdaptedItem) other;
         return Objects.equals(name, otherItem.name)
                 && Objects.equals(price, otherItem.price)
+                && Objects.equals(originalPrice, otherItem.originalPrice)
                 && tagged.equals(otherItem.tagged);
     }
 }

src/test/data/XmlSerializableAddressBookTest/duplicateItemOnlyAddressBook.xml

@@ -4,13 +4,15 @@
     <items>
         <name>Cheese Burger</name>
         <price>3</price>
+        <originalPrice>3</originalPrice>
         <remark></remark>
     </items>
 
     <!-- Item with same identity as Cheese Burger -->
     <items>
         <name>Cheese Burger</name>
         <price>3</price>
+        <originalPrice>3</originalPrice>
         <remark></remark>
     </items>