Merge pull request #450 from yixiann/fix-dates

Ensure we cannot create an item with bought date after expiry date

docs/_ug/commands/ItemCommands.md

@@ -11,15 +11,15 @@ Example of an [Item](#item):
 
 ```info
 * All fields apart from `ITEM_NAME` are optional.
-* The `BOUGHT_DATE` ideally should not be after the `EXPIRY_DATE` but we will allow that.
+* The `BOUGHT_DATE` should not be after the `EXPIRY_DATE`.
 * The format for `BOUGHT_DATE` and `EXPIRY_DATE` should follow: "dd-mm-yyyy".
   * dd: Day of the month. For example, "10" would represent the 10th day of the month.
   * mm: Month of the year, ranging from 1 to 12. This represents the months from January to December. For example, "01" would represent January.
   * yyyy: The current year. For example, "2019" would represent the year 2019.
+* The value of `BOUGHT_DATE`, `EXPIRY_DATE` will be `Not Set` if it is not provided.
 * The default values for `QUANTITY` and `PRICE` is `0`.
 * The default values for `UNIT` is blank.
-* The value of `BOUGHT_DATE`, `EXPIRY_DATE` will be `Not Set` if not provided.
-* The value of `REMARKS` will be `-` if not provided.
+* The value of `REMARKS` will be `-` if is it not provided.
 * `PRICE` do not require you to include the currency. Only include the value.
 * You cannot create an item with a tag immediately.
 * If two or more of the same parameters are provided, the last parameter will be taken.
@@ -258,6 +258,7 @@ Tags: {vegetables}
 
 ```info
 * All fields are optional. However, you need to include at least one parameter.
+* The `BOUGHT_DATE` should not be after the `EXPIRY_DATE`.
 * The format for `BOUGHT_DATE` and `EXPIRY_DATE` should follow: "dd-mm-yyyy".
   * dd: Day of the month. For example, "10" would represent the 10th day of the month.
   * mm: Month of the year, ranging from 1 to 12. This represents the months from January to December. For example, "01" would represent January.

src/main/java/seedu/foodrem/logic/commands/statscommands/StatsCommand.java

@@ -3,8 +3,6 @@
 import static java.util.Objects.requireNonNull;
 import static seedu.foodrem.commons.enums.CommandType.STATS_COMMAND;
 
-import java.time.LocalDate;
-import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
@@ -16,7 +14,7 @@
 import seedu.foodrem.logic.commands.CommandResult;
 import seedu.foodrem.model.Model;
 import seedu.foodrem.model.item.Item;
-import seedu.foodrem.model.item.itemcomparators.ItemCostComparator;
+import seedu.foodrem.model.item.itemcomparators.ItemValueComparator;
 import seedu.foodrem.model.tag.Tag;
 import seedu.foodrem.viewmodels.Stats;
 
@@ -40,15 +38,18 @@ public static String getUsage() {
     }
 
     private List<Item> getTopThreeExpensiveItems(List<Item> itemList) {
-        final List<Item> copy = new ArrayList<>(itemList);
-        copy.sort(new ItemCostComparator().reversed());
-        return copy.subList(0, 3);
+        return itemList.stream()
+                .sorted(new ItemValueComparator().reversed())
+                .limit(3)
+                .collect(Collectors.toList());
     }
 
     private double getAmountWasted(List<Item> itemList) {
         return itemList.stream()
-                .filter(i -> !i.getQuantity().isZero() && i.getExpiryDate().isAfterExpiryDate(LocalDate.now()))
-                .map(i -> i.getPrice().getItemPrice()).reduce(0.0, Double::sum);
+                .filter(Item::hasNonZeroQuantity)
+                .filter(Item::isExpired)
+                .map(Item::getItemValue)
+                .reduce(0.0, Double::sum);
     }
 
     private List<Tag> getTopThreeCommonTags(List<Item> itemList, List<Tag> tagList) {

src/main/java/seedu/foodrem/model/item/Item.java

@@ -3,6 +3,7 @@
 import static java.util.Objects.requireNonNull;
 import static seedu.foodrem.commons.util.CollectionUtil.requireAllNonNull;
 
+import java.time.LocalDate;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
@@ -50,6 +51,12 @@ public Item(ItemName name,
                 ItemRemark remarks,
                 Set<Tag> tagSet) {
         requireAllNonNull(name, quantity, unit, boughtDate, expiryDate, price, remarks, tagSet);
+
+        // Same Bought date and Expiry date is accepted
+        if (!boughtDate.isNotSet() && !expiryDate.isNotSet() && boughtDate.isAfterDate(expiryDate)) {
+            throw new IllegalArgumentException("The item bought date should not be after the item expiry date.");
+        }
+
         this.name = name;
         this.quantity = quantity;
         this.unit = unit;
@@ -106,12 +113,29 @@ public ItemRemark getRemarks() {
         return remarks;
     }
 
-    // TODO: Possibly refactor to avoid using getter methods in ItemPrice and ItemQuantity fields
+    /**
+     * Returns true if the item has expired and false otherwise
+     *
+     * @return The total value of purchasing the specified units of the item.
+     */
+    public boolean isExpired() {
+        return expiryDate.isAfterOrOnDate(LocalDate.now());
+    }
+
+    /**
+     * Returns true if the item quantity is not zero and false otherwise.
+     *
+     * @return The total value of purchasing the specified units of the item.
+     */
+    public boolean hasNonZeroQuantity() {
+        return !quantity.isZero();
+    }
 
     /**
-     * @return The total cost of purchasing the specified units of the item.
+     * @return The total value of purchasing the specified units of the item.
      */
-    public double getItemCost() {
+    public double getItemValue() {
+        // TODO: Possibly refactor to avoid using getter methods in ItemPrice and ItemQuantity fields
         return price.getItemPrice() * quantity.getItemQuantity();
     }
 

src/main/java/seedu/foodrem/model/item/ItemBoughtDate.java

@@ -3,47 +3,40 @@
 import static java.util.Objects.requireNonNull;
 
 import java.time.LocalDate;
-import java.time.format.DateTimeFormatter;
 
 import seedu.foodrem.model.item.itemvalidators.ItemBoughtDateValidator;
 
 /**
- * Represents an item date in an {@link Item}.
+ * Represents an item bought date in an {@link Item}.
  * Guarantees: details are present and not null, field values are validated, immutable.
  */
-public class ItemBoughtDate {
-    // Remember to change relevant messages when changing the regex.
-    public static final String BOUGHT_DATE_PATTERN_REGEX = "dd-MM-uuuu";
-    public static final DateTimeFormatter BOUGHT_DATE_FORMATTER = DateTimeFormatter
-            .ofPattern(BOUGHT_DATE_PATTERN_REGEX);
+public class ItemBoughtDate extends ItemDate {
 
     private static final ItemBoughtDate NOT_SET_BOUGHT_DATE = new ItemBoughtDate(LocalDate.MIN);
 
-    private final LocalDate boughtDate;
-
     /**
      * Constructs an boughtDate.
      *
      * @param date a localDate that represents the boughtDate of the
-     *             format {@link ItemBoughtDate#BOUGHT_DATE_FORMATTER}
+     *             format {@link ItemDate#DATE_PATTERN_REGEX}
      */
     private ItemBoughtDate(LocalDate date) {
-        boughtDate = date;
+        super(date);
     }
 
     /**
      * Produces a boughtDate object.
      *
      * @param dateString a string that represents the boughtDate of the
-     *                   format {@link ItemBoughtDate#BOUGHT_DATE_FORMATTER}
+     *                   format {@link ItemDate#DATE_PATTERN_REGEX}
      */
     public static ItemBoughtDate of(String dateString) {
         requireNonNull(dateString);
         if (dateString.isBlank()) {
             return NOT_SET_BOUGHT_DATE;
         }
         ItemBoughtDateValidator.validate(dateString);
-        return new ItemBoughtDate(LocalDate.parse(dateString, BOUGHT_DATE_FORMATTER));
+        return new ItemBoughtDate(LocalDate.parse(dateString, ItemDate.DATE_FORMATTER));
     }
 
     /**
@@ -54,42 +47,30 @@ public boolean isNotSet() {
     }
 
     /**
-     * Returns {@code true} if both {@link ItemBoughtDate#boughtDate} have the same date by
+     * Returns {@code true} if both {@link ItemBoughtDate} have the same date by
      * {@link LocalDate#equals(Object)}.
      */
     @Override
     public boolean equals(Object other) {
         return other == this
                 || (other != NOT_SET_BOUGHT_DATE
                 && other instanceof ItemBoughtDate
-                && boughtDate.equals(((ItemBoughtDate) other).boughtDate));
-    }
-
-    /**
-     * Compares two item bought dates. The method returns 0 if the bought date is equal to the other
-     * bought date.
-     * A value less than 0 is returned if the bought date is less than the other bought date (earlier) and
-     * a value greater than 0 if the bought date is greater than the other bought date (later).
-     *
-     * @param other The ItemBoughtDate to compare this ItemBoughtDate against.
-     */
-    public int compareTo(ItemBoughtDate other) {
-        return boughtDate.compareTo(other.boughtDate);
+                && getDate().equals(((ItemBoughtDate) other).getDate()));
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public int hashCode() {
-        return boughtDate.hashCode();
+        return super.hashCode();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String toString() {
-        return this == NOT_SET_BOUGHT_DATE ? "" : boughtDate.format(BOUGHT_DATE_FORMATTER);
+        return this == NOT_SET_BOUGHT_DATE ? "" : super.toString();
     }
 }

src/main/java/seedu/foodrem/model/item/ItemDate.java

@@ -0,0 +1,73 @@
+package seedu.foodrem.model.item;
+
+import java.time.LocalDate;
+import java.time.format.DateTimeFormatter;
+
+/**
+ * Represents an item date in an {@link Item}.
+ * Guarantees: details are present and not null, immutable.
+ */
+public abstract class ItemDate {
+    // Remember to change relevant messages displayed to users when changing the regex.
+    public static final String DATE_PATTERN_REGEX = "dd-MM-uuuu";
+    public static final DateTimeFormatter DATE_FORMATTER = DateTimeFormatter
+            .ofPattern(DATE_PATTERN_REGEX);
+
+    private final LocalDate date;
+
+    protected ItemDate(LocalDate date) {
+        this.date = date;
+    }
+
+    public LocalDate getDate() {
+        return date;
+    }
+
+    public int compareTo(ItemDate other) {
+        return date.compareTo(other.date);
+    }
+
+    /**
+     * Returns true if the given datetime object is after or on the same date.
+     *
+     * @param datetime The datetime object to compare against
+     */
+    public boolean isAfterOrOnDate(LocalDate datetime) {
+        return date.isAfter(datetime.minusDays(1));
+    }
+
+    /**
+     * Returns true if the given ItemDate object is after the date.
+     *
+     * @param itemDate The ItemDate object to compare against
+     */
+    public boolean isAfterDate(ItemDate itemDate) {
+        return date.isAfter(itemDate.date);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean equals(Object other) {
+        return other == this
+                && other instanceof ItemDate
+                && date.equals(((ItemDate) other).date);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public int hashCode() {
+        return date.hashCode();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public String toString() {
+        return date.format(DATE_FORMATTER);
+    }
+}