Merge pull request #135 from YingxuH/update-userguide

Update userguide

Author: junhaotan

docs/UserGuide.adoc

@@ -361,6 +361,16 @@ This is a passive feature. Relaunch the window to get the updated information.
 
 image::TopSellingProducts.png[align="center"]
 
+=== View the product sales and quantity histogram.
+
+Displays and updates the histogram of product sales and quantity. +
+
+[NOTE]
+This is a passive feature. Relaunch the histogram window to udpate the plot.
+`F3` key is the short cut for launch/relaunch the window.
+
+image::ViewInventory.png[align="center"]
+
 === Get the revenue made in a certain period : `revenue`
 
 Gets the revenue made in a selected period. +
@@ -434,7 +444,11 @@ Format: `predict`
 === Plotting sales: `plotsales`.
 
 Plot a graph with the sales of the selected product in the past week. +
-Format: `plotsales PRODUCT_INDEX`
+Format: `plotsales PRODUCT_INDEX [sd/START_DATE] [ed/END_DATE]`
+
+[NOTE]
+The start date and end date attributes are optional. If omitted, the system
+will plot the last 7 days by default.
 
 image::SalesPlot.png[align="center"]
 

docs/images/SalesPlot.png

@@ -1,6 +1,8 @@
 package seedu.address.logic.commands.statistics;
 
 import static java.util.Objects.requireNonNull;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_END_DATE;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_START_DATE;
 import static seedu.address.model.transaction.DateTime.populateDates;
 
 import java.util.ArrayList;
@@ -29,8 +31,12 @@ public class PlotProductSalesCommand extends Command {
     public static final String COMMAND_WORD = "plotsales";
 
     public static final String MESSAGE_USAGE = COMMAND_WORD + ": Plot the sales of product to the screen\n"
-            + "Parameters: INDEX (must be a positive integer)\n"
-            + "Example: " + COMMAND_WORD + " 1";
+            + "Parameters: INDEX (must be a positive integer) "
+            + PREFIX_START_DATE + "START DATE "
+            + PREFIX_END_DATE + "END DATE \n"
+            + "Example: " + COMMAND_WORD + " 1 "
+            + PREFIX_START_DATE + "2020-03-20 10:00 "
+            + PREFIX_END_DATE + "2020-03-30 10:00";
 
     public static final String MESSAGE_SUCCESS = "Sales for product %1$s plotted.";
     public static final String TITLE = "Sales of %1$s between %2$s and %3$s";