Implemented unit conversion, with a few problems

TabbedView now displays its units, but with their toString method which shows
their definition in addition to their name

4 files changed, 206 insertions, 20 deletions

diff --git a/src/main/java/sevenUnitsGUI/Presenter.java b/src/main/java/sevenUnitsGUI/Presenter.java
index 23a631d..be02364 100644
--- a/src/main/java/sevenUnitsGUI/Presenter.java
+++ b/src/main/java/sevenUnitsGUI/Presenter.java
@@ -19,17 +19,26 @@ package sevenUnitsGUI;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.OptionalDouble;
 import java.util.Scanner;
+import java.util.Set;
 import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
 import sevenUnits.ProgramInfo;
 import sevenUnits.unit.BaseDimension;
+import sevenUnits.unit.BritishImperial;
+import sevenUnits.unit.Metric;
 import sevenUnits.unit.Unit;
 import sevenUnits.unit.UnitDatabase;
 import sevenUnits.unit.UnitPrefix;
+import sevenUnits.unit.UnitValue;
 import sevenUnits.utils.ObjectProduct;
 import sevenUnits.utils.UncertainDouble;
 
@@ -40,6 +49,44 @@ import sevenUnits.utils.UncertainDouble;
  * @since 2021-12-15
  */
 public final class Presenter {
+	/** The default place where settings are stored. */
+	private static final String DEFAULT_SETTINGS_FILEPATH = "settings.txt";
+	/** The default place where units are stored. */
+	private static final String DEFAULT_UNITS_FILEPATH = "/unitsfile.txt";
+	/** The default place where dimensions are stored. */
+	private static final String DEFAULT_DIMENSIONS_FILEPATH = "/dimensionfile.txt";
+	/** The default place where exceptions are stored. */
+	private static final String DEFAULT_EXCEPTIONS_FILEPATH = "/metric_exceptions.txt";
+	
+	/**
+	 * Adds default units and dimensions to a database.
+	 * 
+	 * @param database database to add to
+	 * @since 2019-04-14
+	 * @since v0.2.0
+	 */
+	private static void addDefaults(final UnitDatabase database) {
+		database.addUnit("metre", Metric.METRE);
+		database.addUnit("kilogram", Metric.KILOGRAM);
+		database.addUnit("gram", Metric.KILOGRAM.dividedBy(1000));
+		database.addUnit("second", Metric.SECOND);
+		database.addUnit("ampere", Metric.AMPERE);
+		database.addUnit("kelvin", Metric.KELVIN);
+		database.addUnit("mole", Metric.MOLE);
+		database.addUnit("candela", Metric.CANDELA);
+		database.addUnit("bit", Metric.BIT);
+		database.addUnit("unit", Metric.ONE);
+		// nonlinear units - must be loaded manually
+		database.addUnit("tempCelsius", Metric.CELSIUS);
+		database.addUnit("tempFahrenheit", BritishImperial.FAHRENHEIT);
+		
+		// load initial dimensions
+		database.addDimension("LENGTH", Metric.Dimensions.LENGTH);
+		database.addDimension("MASS", Metric.Dimensions.MASS);
+		database.addDimension("TIME", Metric.Dimensions.TIME);
+		database.addDimension("TEMPERATURE", Metric.Dimensions.TEMPERATURE);
+	}
+	
 	/**
 	 * @return text in About file
 	 * @since 2022-02-19
@@ -86,6 +133,25 @@ public final class Presenter {
 	}
 	
 	/**
+	 * Accepts a collection and returns a set with the unique elements in that
+	 * collection
+	 *
+	 * @param <E>        type of element in collection
+	 * @param collection collection to uniquify
+	 * @return unique collection
+	 * @since 2022-02-26
+	 */
+	private static <E> Set<E> unique(Collection<E> collection) {
+		final Set<E> uniqueSet = new HashSet<>();
+		for (final E e : collection) {
+			if (!uniqueSet.contains(e)) {
+				uniqueSet.add(e);
+			}
+		}
+		return uniqueSet;
+	}
+	
+	/**
 	 * @return {@code line} with any comments removed.
 	 * @since 2021-03-13
 	 */
@@ -127,6 +193,13 @@ public final class Presenter {
 	private Predicate<List<UnitPrefix>> prefixRepetitionRule;
 	
 	/**
+	 * The set of units that is considered neither metric nor nonmetric for the
+	 * purposes of the metric-imperial one-way conversion. These units are
+	 * included in both From and To, even if One Way Conversion is enabled.
+	 */
+	private final Set<String> metricExceptions;
+	
+	/**
 	 * If this is true, views that show units as a list will have metric units
 	 * removed from the From unit list and imperial/USC units removed from the To
 	 * unit list.
@@ -148,20 +221,43 @@ public final class Presenter {
 	public Presenter(View view) {
 		this.view = view;
 		this.database = new UnitDatabase();
+		addDefaults(this.database);
+		
+		// load units and prefixes
+		try (final InputStream units = inputStream(DEFAULT_UNITS_FILEPATH)) {
+			this.database.loadUnitsFromStream(units);
+		} catch (final IOException e) {
+			throw new AssertionError("Loading of unitsfile.txt failed.", e);
+		}
+		
+		// load dimensions
+		try (final InputStream dimensions = inputStream(
+				DEFAULT_DIMENSIONS_FILEPATH)) {
+			this.database.loadDimensionsFromStream(dimensions);
+		} catch (final IOException e) {
+			throw new AssertionError("Loading of dimensionfile.txt failed.", e);
+		}
+		
+		// load metric exceptions
+		try {
+			this.metricExceptions = new HashSet<>();
+			try (InputStream exceptions = inputStream(DEFAULT_EXCEPTIONS_FILEPATH);
+					Scanner scanner = new Scanner(exceptions)) {
+				while (scanner.hasNextLine()) {
+					final String line = Presenter
+							.withoutComments(scanner.nextLine());
+					if (!line.isBlank()) {
+						this.metricExceptions.add(line);
+					}
+				}
+			}
+		} catch (final IOException e) {
+			throw new AssertionError("Loading of metric_exceptions.txt failed.",
+					e);
+		}
 	}
 	
 	/**
-	 * Sets the dimension of the view's From and To units.
-	 * 
-	 * @throws UnsupportedOperationException if the view does not support
-	 *                                       unit-based conversion (does not
-	 *                                       implement
-	 *                                       {@link UnitConversionView})
-	 * @since 2021-12-15
-	 */
-	public void applyDimensionFilter() {}
-	
-	/**
 	 * Gets settings from the view and applies them to both view and presenter.
 	 * 
 	 * @since 2021-12-15
@@ -190,7 +286,52 @@ public final class Presenter {
 	 *                                       {@link UnitConversionView})
 	 * @since 2021-12-15
 	 */
-	public void convertUnits() {}
+	public void convertUnits() {
+		if (this.view instanceof UnitConversionView) {
+			final UnitConversionView ucview = (UnitConversionView) this.view;
+			
+			final Optional<Unit> fromUnitOptional = ucview.getFromSelection();
+			final Optional<Unit> toUnitOptional = ucview.getToSelection();
+			final OptionalDouble valueOptional = ucview.getInputValue();
+			
+			// ensure everything is obtained
+			final Unit fromUnit, toUnit;
+			final double value;
+			if (fromUnitOptional.isPresent()) {
+				fromUnit = fromUnitOptional.orElseThrow();
+			} else {
+				this.view.showErrorMessage("Unit Conversion Error",
+						"Please specify a From unit");
+				return;
+			}
+			if (toUnitOptional.isPresent()) {
+				toUnit = toUnitOptional.orElseThrow();
+			} else {
+				this.view.showErrorMessage("Unit Conversion Error",
+						"Please specify a To unit");
+				return;
+			}
+			if (valueOptional.isPresent()) {
+				value = valueOptional.orElseThrow();
+			} else {
+				this.view.showErrorMessage("Unit Conversion Error",
+						"Please specify a valid value");
+				return;
+			}
+			
+			if (!fromUnit.canConvertTo(toUnit))
+				throw new AssertionError(
+						"From and To units incompatible (should be impossible)");
+			
+			// convert!
+			final UnitValue initialValue = UnitValue.of(fromUnit, value);
+			final UnitValue converted = initialValue.convertTo(toUnit);
+			ucview.showUnitConversionOutput(
+					String.format("%s = %s", initialValue, converted));
+		} else
+			throw new UnsupportedOperationException(
+					"This function can only be called when the view is a UnitConversionView.");
+	}
 	
 	/**
 	 * Loads settings from the user's settings file and applies them to the view.
@@ -199,6 +340,21 @@ public final class Presenter {
 	 */
 	public void loadSettings() {}
 	
+	/**
+	 * Completes creation of the presenter. This part of the initialization
+	 * depends on the view's functions, so it cannot be run if the components
+	 * they depend on are not created yet.
+	 * 
+	 * @since 2022-02-26
+	 */
+	public void postViewInitialize() {
+		// unit conversion specific stuff
+		if (this.view instanceof UnitConversionView) {
+			final UnitConversionView ucview = (UnitConversionView) this.view;
+			ucview.setDimensions(unique(this.database.dimensionMap().values()));
+		}
+	}
+	
 	void prefixSelected() {}
 	
 	/**
@@ -227,4 +383,26 @@ public final class Presenter {
 	}
 	
 	void unitNameSelected() {}
+	
+	/**
+	 * Updates the view's From and To units, if it has some
+	 * 
+	 * @since 2021-12-15
+	 */
+	public void updateView() {
+		if (this.view instanceof UnitConversionView) {
+			final UnitConversionView ucview = (UnitConversionView) this.view;
+			final ObjectProduct<BaseDimension> viewDimension = ucview
+					.getSelectedDimension().orElseThrow();
+			
+			final Set<Unit> units = this.database
+					.unitMapPrefixless(this.showDuplicateUnits).entrySet().stream()
+					.map(Map.Entry::getValue)
+					.filter(u -> viewDimension.equals(u.getDimension()))
+					.collect(Collectors.toSet());
+			
+			ucview.setFromUnits(units);
+			ucview.setToUnits(units);
+		}
+	}
 }
diff --git a/src/main/java/sevenUnitsGUI/TabbedView.java b/src/main/java/sevenUnitsGUI/TabbedView.java
index e92b661..c3a05e2 100644
--- a/src/main/java/sevenUnitsGUI/TabbedView.java
+++ b/src/main/java/sevenUnitsGUI/TabbedView.java
@@ -28,6 +28,7 @@ import java.util.Collections;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Optional;
+import java.util.OptionalDouble;
 import java.util.Set;
 
 import javax.swing.BorderFactory;
@@ -212,7 +213,7 @@ final class TabbedView implements ExpressionConversionView, UnitConversionView {
 			this.dimensionSelector = new JComboBox<>();
 			inBetweenPanel.add(this.dimensionSelector, BorderLayout.PAGE_START);
 			this.dimensionSelector
-					.addItemListener(e -> this.presenter.applyDimensionFilter());
+					.addItemListener(e -> this.presenter.updateView());
 			
 			final JLabel arrowLabel = new JLabel("-->");
 			inBetweenPanel.add(arrowLabel, BorderLayout.CENTER);
@@ -326,9 +327,9 @@ final class TabbedView implements ExpressionConversionView, UnitConversionView {
 		this.masterPane.setMnemonicAt(5, KeyEvent.VK_S);
 		
 		// ============ FINALIZE CREATION OF VIEW ============
+		this.presenter.postViewInitialize();
 		this.frame.pack();
 		this.frame.setVisible(true);
-		
 	}
 	
 	/**
@@ -541,8 +542,13 @@ final class TabbedView implements ExpressionConversionView, UnitConversionView {
 	}
 	
 	@Override
-	public String getInputValue() {
-		return this.valueInput.getText();
+	public OptionalDouble getInputValue() {
+		final String text = this.valueInput.getText();
+		try {
+			return OptionalDouble.of(Double.parseDouble(text));
+		} catch (final NumberFormatException e) {
+			return OptionalDouble.empty();
+		}
 	}
 	
 	@Override
diff --git a/src/main/java/sevenUnitsGUI/UnitConversionView.java b/src/main/java/sevenUnitsGUI/UnitConversionView.java
index 5fd5a82..e411a44 100644
--- a/src/main/java/sevenUnitsGUI/UnitConversionView.java
+++ b/src/main/java/sevenUnitsGUI/UnitConversionView.java
@@ -17,6 +17,7 @@
 package sevenUnitsGUI;
 
 import java.util.Optional;
+import java.util.OptionalDouble;
 import java.util.Set;
 
 import sevenUnits.unit.BaseDimension;
@@ -48,7 +49,7 @@ public interface UnitConversionView extends View {
 	 *         string provided by the user)
 	 * @since 2021-12-15
 	 */
-	String getInputValue();
+	OptionalDouble getInputValue();
 	
 	/**
 	 * @return selected dimension
diff --git a/src/main/java/sevenUnitsGUI/ViewBot.java b/src/main/java/sevenUnitsGUI/ViewBot.java
index 0c0d189..bc5302b 100644
--- a/src/main/java/sevenUnitsGUI/ViewBot.java
+++ b/src/main/java/sevenUnitsGUI/ViewBot.java
@@ -20,6 +20,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
+import java.util.OptionalDouble;
 import java.util.Set;
 
 import sevenUnits.unit.BaseDimension;
@@ -47,7 +48,7 @@ final class ViewBot implements UnitConversionView, ExpressionConversionView {
 	/**
 	 * The user-provided string representing the value in {@code fromSelection}
 	 */
-	private String inputValue;
+	private OptionalDouble inputValue;
 	/** The unit selected in the From selection */
 	private Optional<Unit> fromSelection;
 	/** The unit selected in the To selection */
@@ -102,7 +103,7 @@ final class ViewBot implements UnitConversionView, ExpressionConversionView {
 	}
 	
 	@Override
-	public String getInputValue() {
+	public OptionalDouble getInputValue() {
 		return this.inputValue;
 	}
 	
@@ -190,7 +191,7 @@ final class ViewBot implements UnitConversionView, ExpressionConversionView {
 	 * @param inputValue the inputValue to set
 	 * @since 2022-01-29
 	 */
-	public void setInputValue(String inputValue) {
+	public void setInputValue(OptionalDouble inputValue) {
 		this.inputValue = inputValue;
 	}