Implemented one-way conversion, duplicate prefixes can now be hidden

6 files changed, 90 insertions, 47 deletions

diff --git a/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java b/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
index e10bab4..309bdb9 100644
--- a/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
+++ b/src/main/java/sevenUnits/converterGUI/SevenUnitsGUI.java
@@ -298,7 +298,8 @@ final class SevenUnitsGUI {
 					this.database.unitMapPrefixless(true).keySet());
 			this.unitNames.sort(null); // sorts it using Comparable
 			
-			this.prefixNames = new ArrayList<>(this.database.prefixMap().keySet());
+			this.prefixNames = new ArrayList<>(
+					this.database.prefixMap(true).keySet());
 			this.prefixNames.sort(this.prefixNameComparator); // sorts it using my
 																				// comparator
 			
@@ -611,7 +612,7 @@ final class SevenUnitsGUI {
 		 * @since v0.2.0
 		 */
 		public final Set<String> prefixNameSet() {
-			return this.database.prefixMap().keySet();
+			return this.database.prefixMap(true).keySet();
 		}
 		
 		/**
diff --git a/src/main/java/sevenUnits/unit/BritishImperial.java b/src/main/java/sevenUnits/unit/BritishImperial.java
index c6e65fb..0ecba6d 100644
--- a/src/main/java/sevenUnits/unit/BritishImperial.java
+++ b/src/main/java/sevenUnits/unit/BritishImperial.java
@@ -121,5 +121,5 @@ public final class BritishImperial {
 	public static final Unit FAHRENHEIT = Unit
 			.fromConversionFunctions(Metric.KELVIN.getBase(),
 					tempK -> tempK * 1.8 - 459.67, tempF -> (tempF + 459.67) / 1.8)
-			.withName(NameSymbol.of("degrees Fahrenheit", "\u00B0F"));
+			.withName(NameSymbol.of("degree Fahrenheit", "\u00B0F"));
 }
diff --git a/src/main/java/sevenUnits/unit/UnitDatabase.java b/src/main/java/sevenUnits/unit/UnitDatabase.java
index a4f0c44..71676a1 100644
--- a/src/main/java/sevenUnits/unit/UnitDatabase.java
+++ b/src/main/java/sevenUnits/unit/UnitDatabase.java
@@ -1160,16 +1160,16 @@ public final class UnitDatabase {
 	}
 	
 	/**
-	 * @return true if entry represents a removable duplicate entry of unitMap.
+	 * @return true if entry represents a removable duplicate entry of map.
 	 * @since 2021-05-22
 	 */
-	static boolean isRemovableDuplicate(Map<String, Unit> unitMap,
-			Entry<String, Unit> entry) {
-		for (final Entry<String, Unit> e : unitMap.entrySet()) {
+	static <T> boolean isRemovableDuplicate(Map<String, T> map,
+			Entry<String, T> entry) {
+		for (final Entry<String, T> e : map.entrySet()) {
 			final String name = e.getKey();
-			final Unit value = e.getValue();
+			final T value = e.getValue();
 			if (lengthFirstComparator.compare(entry.getKey(), name) < 0
-					&& Objects.equals(unitMap.get(entry.getKey()), value))
+					&& Objects.equals(map.get(entry.getKey()), value))
 				return true;
 		}
 		return false;
@@ -2010,12 +2010,18 @@ public final class UnitDatabase {
 	}
 	
 	/**
+	 * @param includeDuplicates if false, duplicates are removed from the map
 	 * @return a map mapping prefix names to prefixes
-	 * @since 2019-04-13
-	 * @since v0.2.0
+	 * @since 2022-04-18
+	 * @since v0.4.0
 	 */
-	public Map<String, UnitPrefix> prefixMap() {
-		return Collections.unmodifiableMap(this.prefixes);
+	public Map<String, UnitPrefix> prefixMap(boolean includeDuplicates) {
+		if (includeDuplicates)
+			return Collections.unmodifiableMap(this.prefixes);
+		else
+			return Collections.unmodifiableMap(ConditionalExistenceCollections
+					.conditionalExistenceMap(this.prefixes,
+							entry -> !isRemovableDuplicate(this.prefixes, entry)));
 	}
 	
 	/**
diff --git a/src/main/java/sevenUnits/unit/UnitType.java b/src/main/java/sevenUnits/unit/UnitType.java
index a13051a..7cebf2d 100644
--- a/src/main/java/sevenUnits/unit/UnitType.java
+++ b/src/main/java/sevenUnits/unit/UnitType.java
@@ -16,6 +16,8 @@
  */
 package sevenUnits.unit;
 
+import java.util.function.Predicate;
+
 /**
  * A type of unit, as chosen by the type of system it is in.
  * <ul>
@@ -31,4 +33,26 @@ package sevenUnits.unit;
  */
 public enum UnitType {
 	METRIC, SEMI_METRIC, NON_METRIC;
+	
+	/**
+	 * Determines which type a unit is. The type will be:
+	 * <ul>
+	 * <li>{@code SEMI_METRIC} if the unit passes the provided predicate
+	 * <li>{@code METRIC} if it fails the predicate but is metric
+	 * <li>{@code NON_METRIC} if it fails the predicate and is not metric
+	 * </ul>
+	 *
+	 * @param u            unit to test
+	 * @param isSemiMetric predicate to determine if a unit is semi-metric
+	 * @return type of unit
+	 * @since 2022-04-18
+	 */
+	public static final UnitType getType(Unit u, Predicate<Unit> isSemiMetric) {
+		if (isSemiMetric.test(u))
+			return SEMI_METRIC;
+		else if (u.isMetric())
+			return METRIC;
+		else
+			return NON_METRIC;
+	}
 }
diff --git a/src/main/java/sevenUnitsGUI/Presenter.java b/src/main/java/sevenUnitsGUI/Presenter.java
index 85a0ddc..f4f3e3a 100644
--- a/src/main/java/sevenUnitsGUI/Presenter.java
+++ b/src/main/java/sevenUnitsGUI/Presenter.java
@@ -30,6 +30,7 @@ import java.util.Set;
 import java.util.function.Function;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import sevenUnits.ProgramInfo;
 import sevenUnits.unit.BaseDimension;
@@ -194,10 +195,10 @@ public final class Presenter {
 	private boolean oneWayConversionEnabled;
 	
 	/**
-	 * If this is false, duplicate units will be removed from the unit view in
-	 * views that show units as a list to choose from.
+	 * If this is false, duplicate units and prefixes will be removed from the
+	 * unit view in views that show units as a list to choose from.
 	 */
-	private boolean showDuplicateUnits;
+	private boolean showDuplicates;
 	
 	/**
 	 * Creates a Presenter
@@ -416,8 +417,8 @@ public final class Presenter {
 	 * @return true iff duplicate units are shown in unit lists
 	 * @since 2022-03-30
 	 */
-	public boolean duplicateUnitsShown() {
-		return this.showDuplicateUnits;
+	public boolean duplicatesShown() {
+		return this.showDuplicates;
 	}
 	
 	/**
@@ -455,25 +456,18 @@ public final class Presenter {
 	}
 	
 	/**
-	 * @return type of unit {@code u}
+	 * @return whether or not the provided unit is semi-metric (i.e. an
+	 *         exception)
 	 * @since 2022-04-16
 	 */
-	private final UnitType getUnitType(Unit u) {
+	private final boolean isSemiMetric(Unit u) {
 		// determine if u is an exception
 		final var primaryName = u.getPrimaryName();
 		final var symbol = u.getSymbol();
-		final boolean isException = primaryName.isPresent()
+		return primaryName.isPresent()
 				&& this.metricExceptions.contains(primaryName.orElseThrow())
 				|| symbol.isPresent()
 						&& this.metricExceptions.contains(symbol.orElseThrow());
-		
-		// determine unit type
-		if (isException)
-			return UnitType.SEMI_METRIC;
-		else if (u.isMetric())
-			return UnitType.METRIC;
-		else
-			return UnitType.NON_METRIC;
 	}
 	
 	/**
@@ -510,10 +504,7 @@ public final class Presenter {
 			ucview.setDimensionNames(this.database.dimensionMap().keySet());
 		}
 		
-		// load units & prefixes into viewers
-		this.view.setViewableUnitNames(
-				this.database.unitMapPrefixless(this.showDuplicateUnits).keySet());
-		this.view.setViewablePrefixNames(this.database.prefixMap().keySet());
+		this.updateView();
 	}
 	
 	void prefixSelected() {
@@ -572,8 +563,8 @@ public final class Presenter {
 	 * @param showDuplicateUnits whether or not duplicate units should be shown
 	 * @since 2022-03-30
 	 */
-	public void setShowDuplicateUnits(boolean showDuplicateUnits) {
-		this.showDuplicateUnits = showDuplicateUnits;
+	public void setShowDuplicates(boolean showDuplicateUnits) {
+		this.showDuplicates = showDuplicateUnits;
 		this.updateView();
 	}
 	
@@ -589,7 +580,7 @@ public final class Presenter {
 				|| u instanceof LinearUnit && ((LinearUnit) u).isBase();
 		final var definition = isBase ? "(Base unit)" : u.toDefinitionString();
 		final var dimensionString = this.getDimensionName(u.getDimension());
-		final var unitType = this.getUnitType(u);
+		final var unitType = UnitType.getType(u, this::isSemiMetric);
 		this.view.showUnit(nameSymbol, definition, dimensionString, unitType);
 	}
 	
@@ -621,14 +612,36 @@ public final class Presenter {
 					.getDimension(((UnitConversionView) this.view)
 							.getSelectedDimensionName().orElseThrow());
 			
-			final Set<String> units = this.database
-					.unitMapPrefixless(this.showDuplicateUnits).entrySet().stream()
+			// load units & prefixes into viewers
+			this.view.setViewableUnitNames(
+					this.database.unitMapPrefixless(this.showDuplicates).keySet());
+			this.view.setViewablePrefixNames(
+					this.database.prefixMap(this.showDuplicates).keySet());
+			
+			// get From and To units
+			Stream<Unit> fromUnits = this.database
+					.unitMapPrefixless(this.showDuplicates).entrySet().stream()
 					.map(Map.Entry::getValue)
-					.filter(u -> viewDimension.equals(u.getDimension()))
-					.map(Unit::getName).collect(Collectors.toSet());
+					.filter(u -> viewDimension.equals(u.getDimension()));
+			
+			Stream<Unit> toUnits = this.database
+					.unitMapPrefixless(this.showDuplicates).entrySet().stream()
+					.map(Map.Entry::getValue)
+					.filter(u -> viewDimension.equals(u.getDimension()));
+			
+			// filter by unit type, if desired
+			if (this.oneWayConversionEnabled) {
+				fromUnits = fromUnits.filter(u -> UnitType.getType(u,
+						this::isSemiMetric) != UnitType.METRIC);
+				toUnits = toUnits.filter(u -> UnitType.getType(u,
+						this::isSemiMetric) != UnitType.NON_METRIC);
+			}
 			
-			ucview.setFromUnitNames(units);
-			ucview.setToUnitNames(units);
+			// set unit names
+			ucview.setFromUnitNames(
+					fromUnits.map(Unit::getName).collect(Collectors.toSet()));
+			ucview.setToUnitNames(
+					toUnits.map(Unit::getName).collect(Collectors.toSet()));
 		}
 	}
 	
diff --git a/src/main/java/sevenUnitsGUI/TabbedView.java b/src/main/java/sevenUnitsGUI/TabbedView.java
index 3a951ef..098c374 100644
--- a/src/main/java/sevenUnitsGUI/TabbedView.java
+++ b/src/main/java/sevenUnitsGUI/TabbedView.java
@@ -634,11 +634,10 @@ final class TabbedView implements ExpressionConversionView, UnitConversionView {
 					.setAnchor(GridBagConstraints.LINE_START).build());
 			
 			final JCheckBox showAllVariations = new JCheckBox(
-					"Show Duplicates in \"Convert Units\"");
-			showAllVariations.setSelected(this.presenter.duplicateUnitsShown());
-			showAllVariations
-					.addItemListener(e -> this.presenter.setShowDuplicateUnits(
-							e.getStateChange() == ItemEvent.SELECTED));
+					"Show Duplicate Units & Prefixes");
+			showAllVariations.setSelected(this.presenter.duplicatesShown());
+			showAllVariations.addItemListener(e -> this.presenter
+					.setShowDuplicates(e.getStateChange() == ItemEvent.SELECTED));
 			miscPanel.add(showAllVariations, new GridBagBuilder(0, 1)
 					.setAnchor(GridBagConstraints.LINE_START).build());