3 files changed, 754 insertions, 0 deletions
diff --git a/base/src/main/java/bjc/utils/gen/RandomGrammar.java b/base/src/main/java/bjc/utils/gen/RandomGrammar.java
new file mode 100644
index 0000000..3de08d6
--- /dev/null
+++ b/base/src/main/java/bjc/utils/gen/RandomGrammar.java
@@ -0,0 +1,69 @@
+package bjc.utils.gen;
+
+import bjc.utils.funcdata.FunctionalMap;
+import bjc.utils.funcdata.IList;
+
+/**
+ * A weighted grammar where all the rules have a equal chance of occuring.
+ *
+ * @author ben
+ *
+ * @param <E>
+ *                The type of grammar elements to use.
+ */
+public class RandomGrammar<E> extends WeightedGrammar<E> {
+	/**
+	 * Create a new random grammar.
+	 */
+	public RandomGrammar() {
+		rules = new FunctionalMap<>();
+	}
+
+	/**
+	 * Add cases to a specified rule.
+	 *
+	 * @param rule
+	 *                The name of the rule to add cases to.
+	 * @param cases
+	 *                The cases to add for this rule.
+	 */
+	@SafeVarargs
+	public final void addCases(final E rule, final IList<E>... cases) {
+		for (final IList<E> currentCase : cases) {
+			super.addCase(rule, 1, currentCase);
+		}
+	}
+
+	/**
+	 * Create a rule with the specified name and cases.
+	 *
+	 * @param rule
+	 *                The name of the rule to add.
+	 * @param cases
+	 *                The cases to add for this rule.
+	 */
+	@SafeVarargs
+	public final void makeRule(final E rule, final IList<E>... cases) {
+		super.addRule(rule);
+
+		for (final IList<E> currentCase : cases) {
+			super.addCase(rule, 1, currentCase);
+		}
+	}
+
+	/**
+	 * Create a rule with the specified name and cases.
+	 *
+	 * @param rule
+	 *                The name of the rule to add.
+	 * @param cases
+	 *                The cases to add for this rule.
+	 */
+	public void makeRule(final E rule, final IList<IList<E>> cases) {
+		if (cases == null) throw new NullPointerException("Cases must not be null");
+
+		super.addRule(rule);
+
+		cases.forEach(currentCase -> super.addCase(rule, 1, currentCase));
+	}
+}
diff --git a/base/src/main/java/bjc/utils/gen/WeightedGrammar.java b/base/src/main/java/bjc/utils/gen/WeightedGrammar.java
new file mode 100644
index 0000000..7777ad8
--- /dev/null
+++ b/base/src/main/java/bjc/utils/gen/WeightedGrammar.java
@@ -0,0 +1,573 @@
+package bjc.utils.gen;
+
+import java.util.Random;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import java.util.function.Supplier;
+
+import bjc.utils.data.IPair;
+import bjc.utils.data.Pair;
+import bjc.utils.funcdata.FunctionalList;
+import bjc.utils.funcdata.FunctionalMap;
+import bjc.utils.funcdata.IList;
+import bjc.utils.funcdata.IMap;
+
+/**
+ * A random grammar, where certain rules will come up more often than others.
+ *
+ * @author ben
+ *
+ * @param <E>
+ *                The values that make up sentences of this grammar.
+ */
+public class WeightedGrammar<E> {
+	/**
+	 * The initial rule of the grammar
+	 */
+	protected String initialRule;
+
+	/**
+	 * The rules currently in this grammar
+	 */
+	protected IMap<E, WeightedRandom<IList<E>>> rules;
+
+	/**
+	 * The random number generator used for random numbers
+	 */
+	private Random rng;
+
+	/**
+	 * All of the subgrammars of this grammar
+	 */
+	protected IMap<E, WeightedGrammar<E>> subgrammars;
+
+	/**
+	 * Rules that require special handling
+	 */
+	private IMap<E, Supplier<IList<E>>> specialRules;
+
+	/**
+	 * Predicate for marking special tokens
+	 */
+
+	private Predicate<E> specialMarker;
+
+	/**
+	 * Action for special tokens
+	 */
+	private BiFunction<E, WeightedGrammar<E>, IList<E>> specialAction;
+
+	/**
+	 * Create a new weighted grammar.
+	 */
+	public WeightedGrammar() {
+		rules = new FunctionalMap<>();
+		subgrammars = new FunctionalMap<>();
+		specialRules = new FunctionalMap<>();
+	}
+
+	/**
+	 * Create a new weighted grammar that uses the specified source of
+	 * randomness.
+	 *
+	 * @param source
+	 *                The source of randomness to use
+	 */
+	public WeightedGrammar(final Random source) {
+		this();
+
+		if (source == null) throw new NullPointerException("Source of randomness must be non-null");
+
+		rng = source;
+	}
+
+	/**
+	 * Configure the action to perform on special tokens.
+	 *
+	 * @param marker
+	 *                The marker to find special tokens.
+	 *
+	 * @param action
+	 *                The action to take on those tokens.
+	 */
+	public void configureSpecial(final Predicate<E> marker,
+			final BiFunction<E, WeightedGrammar<E>, IList<E>> action) {
+		specialMarker = marker;
+		specialAction = action;
+	}
+
+	/**
+	 * Adds a special rule to the grammar.
+	 *
+	 * @param ruleName
+	 *                The name of the special rule.
+	 *
+	 * @param cse
+	 *                The case for the rule.
+	 */
+	public void addSpecialRule(final E ruleName, final Supplier<IList<E>> cse) {
+		if (ruleName == null)
+			throw new NullPointerException("Rule name must not be null");
+		else if (cse == null) throw new NullPointerException("Case must not be null");
+
+		specialRules.put(ruleName, cse);
+	}
+
+	/**
+	 * Add a case to an already existing rule.
+	 *
+	 * @param ruleName
+	 *                The rule to add a case to.
+	 * @param probability
+	 *                The probability for this rule to be chosen.
+	 * @param cse
+	 *                The case being added.
+	 */
+	public void addCase(final E ruleName, final int probability, final IList<E> cse) {
+		if (ruleName == null)
+			throw new NullPointerException("Rule name must be not null");
+		else if (cse == null) throw new NullPointerException("Case body must not be null");
+
+		rules.get(ruleName).addProbability(probability, cse);
+	}
+
+	/**
+	 * Add a alias for an existing subgrammar
+	 *
+	 * @param name
+	 *                The name of the subgrammar to alias
+	 * @param alias
+	 *                The alias of the subgrammar
+	 * @return Whether the alias was succesfully created
+	 */
+	public boolean addGrammarAlias(final E name, final E alias) {
+		if (name == null)
+			throw new NullPointerException("Subgrammar name must not be null");
+		else if (alias == null) throw new NullPointerException("Subgrammar alias must not be null");
+
+		if (subgrammars.containsKey(alias)) return false;
+
+		if (subgrammars.containsKey(name)) {
+			subgrammars.put(alias, subgrammars.get(name));
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Add a new rule with no cases.
+	 *
+	 * @param name
+	 *                The name of the rule to add.
+	 * @return Whether or not the rule was successfully added.
+	 */
+	public boolean addRule(final E name) {
+		if (rng == null) {
+			rng = new Random();
+		}
+
+		if (name == null) throw new NullPointerException("Rule name must not be null");
+
+		return addRule(name, new WeightedRandom<>(rng));
+	}
+
+	/**
+	 * Add a new rule with a set of cases.
+	 *
+	 * @param name
+	 *                The name of the rule to add.
+	 * @param cases
+	 *                The set of cases for the rule.
+	 * @return Whether or not the rule was succesfully added.
+	 */
+	public boolean addRule(final E name, final WeightedRandom<IList<E>> cases) {
+		if (name == null)
+			throw new NullPointerException("Name must not be null");
+		else if (cases == null) throw new NullPointerException("Cases must not be null");
+
+		if (rules.containsKey(name)) return false;
+
+		rules.put(name, cases);
+		return true;
+	}
+
+	/**
+	 * Add a subgrammar.
+	 *
+	 * @param name
+	 *                The name of the subgrammar.
+	 * @param subgrammar
+	 *                The subgrammar to add.
+	 * @return Whether or not the subgrammar was succesfully added.
+	 */
+	public boolean addSubgrammar(final E name, final WeightedGrammar<E> subgrammar) {
+		if (name == null)
+			throw new NullPointerException("Subgrammar name must not be null");
+		else if (subgrammar == null) throw new NullPointerException("Subgrammar must not be null");
+
+		if (subgrammars.containsKey(name)) return false;
+
+		subgrammars.put(name, subgrammar);
+		return true;
+	}
+
+	/**
+	 * Remove a rule with the specified name.
+	 *
+	 * @param name
+	 *                The name of the rule to remove.
+	 */
+	public void deleteRule(final E name) {
+		if (name == null) throw new NullPointerException("Rule name must not be null");
+
+		rules.remove(name);
+	}
+
+	/**
+	 * Remove a subgrammar with the specified name.
+	 *
+	 * @param name
+	 *                The name of the subgrammar to remove.
+	 */
+	public void deleteSubgrammar(final E name) {
+		if (name == null) throw new NullPointerException("Rule name must not be null");
+
+		subgrammars.remove(name);
+	}
+
+	/**
+	 * Generate a set of debug sentences for the specified rule.
+	 *
+	 * Only generates sentences one layer deep.
+	 *
+	 * @param ruleName
+	 *                The rule to test.
+	 * @return A set of sentences generated by the specified rule.
+	 */
+	public IList<IList<E>> generateDebugValues(final E ruleName) {
+		if (ruleName == null) throw new NullPointerException("Rule name must not be null");
+
+		final IList<IList<E>> returnedList = new FunctionalList<>();
+
+		final WeightedRandom<IList<E>> ruleGenerator = rules.get(ruleName);
+
+		for (int i = 0; i < 10; i++) {
+			returnedList.add(ruleGenerator.generateValue());
+		}
+
+		return returnedList;
+	}
+
+	/**
+	 * Generate a generic sentence from a initial rule.
+	 *
+	 * @param <T>
+	 *                The type of the transformed output
+	 *
+	 * @param initRules
+	 *                The initial rule to start with.
+	 *
+	 * @param tokenTransformer
+	 *                The function to transform grammar output into
+	 *                something.
+	 *
+	 * @param spacer
+	 *                The spacer element to add in between output tokens.
+	 *
+	 * @return A randomly generated sentence from the specified initial
+	 *         rule.
+	 */
+	public <T> IList<T> generateGenericValues(final E initRules, final Function<E, T> tokenTransformer,
+			final T spacer) {
+		if (initRules == null)
+			throw new NullPointerException("Initial rule must not be null");
+		else if (tokenTransformer == null)
+			throw new NullPointerException("Transformer must not be null");
+		else if (spacer == null) throw new NullPointerException("Spacer must not be null");
+
+		final IList<T> returnedList = new FunctionalList<>();
+
+		IList<E> genRules = new FunctionalList<>(initRules);
+
+		if (specialMarker != null) {
+			if (specialMarker.test(initRules)) {
+				genRules = specialAction.apply(initRules, this);
+			}
+		}
+
+		for (final E initRule : genRules.toIterable()) {
+			if (specialRules.containsKey(initRule)) {
+				for (final E rulePart : specialRules.get(initRule).get().toIterable()) {
+					final Iterable<T> generatedRuleParts = generateGenericValues(rulePart,
+							tokenTransformer, spacer).toIterable();
+
+					for (final T generatedRulePart : generatedRuleParts) {
+						returnedList.add(generatedRulePart);
+						returnedList.add(spacer);
+					}
+				}
+			} else if (subgrammars.containsKey(initRule)) {
+				final Iterable<T> ruleParts = subgrammars.get(initRule)
+						.generateGenericValues(initRule, tokenTransformer, spacer).toIterable();
+
+				for (final T rulePart : ruleParts) {
+					returnedList.add(rulePart);
+					returnedList.add(spacer);
+				}
+			} else if (rules.containsKey(initRule)) {
+				final Iterable<E> ruleParts = rules.get(initRule).generateValue().toIterable();
+
+				for (final E rulePart : ruleParts) {
+					final Iterable<T> generatedRuleParts = generateGenericValues(rulePart,
+							tokenTransformer, spacer).toIterable();
+
+					for (final T generatedRulePart : generatedRuleParts) {
+						returnedList.add(generatedRulePart);
+						returnedList.add(spacer);
+					}
+				}
+			} else {
+				final T transformedToken = tokenTransformer.apply(initRule);
+
+				if (transformedToken == null)
+					throw new NullPointerException("Transformer created null token");
+
+				returnedList.add(transformedToken);
+				returnedList.add(spacer);
+			}
+		}
+
+		return returnedList;
+	}
+
+	/**
+	 * Generate a random list of grammar elements from a given initial rule.
+	 *
+	 * @param initRule
+	 *                The initial rule to start with.
+	 * @param spacer
+	 *                The item to use to space the list.
+	 * @return A list of random grammar elements generated by the specified
+	 *         rule.
+	 */
+	public IList<E> generateListValues(final E initRule, final E spacer) {
+		final IList<E> retList = generateGenericValues(initRule, strang -> strang, spacer);
+
+		return retList;
+	}
+
+	/**
+	 * Get the initial rule of this grammar
+	 *
+	 * @return The initial rule of this grammar
+	 */
+	public String getInitialRule() {
+		return initialRule;
+	}
+
+	/**
+	 * Returns the number of rules in this grammar
+	 *
+	 * @return The number of rules in this grammar
+	 */
+	public int getRuleCount() {
+		return rules.size();
+	}
+
+	/**
+	 * Returns a set containing all of the rules in this grammar
+	 *
+	 * @return The set of all rule names in this grammar
+	 */
+	public IList<E> getRuleNames() {
+		final IList<E> ruleNames = new FunctionalList<>();
+
+		ruleNames.addAll(rules.keyList());
+		ruleNames.addAll(specialRules.keyList());
+
+		return ruleNames;
+	}
+
+	/**
+	 * Get the subgrammar with the specified name.
+	 *
+	 * @param name
+	 *                The name of the subgrammar to get.
+	 * @return The subgrammar with the specified name.
+	 */
+	public WeightedGrammar<E> getSubgrammar(final E name) {
+		if (name == null) throw new NullPointerException("Subgrammar name must not be null");
+
+		return subgrammars.get(name);
+	}
+
+	/**
+	 * Check if this grammar has an initial rule
+	 *
+	 * @return Whether or not this grammar has an initial rule
+	 */
+	public boolean hasInitialRule() {
+		return initialRule != null && !initialRule.equalsIgnoreCase("");
+	}
+
+	/**
+	 * Check if this grammar has a given rule.
+	 *
+	 * @param ruleName
+	 *                The rule to check for.
+	 *
+	 * @return Whether or not the grammar has a rule by that name.
+	 */
+	public boolean hasRule(final E ruleName) {
+		return rules.containsKey(ruleName) || specialRules.containsKey(ruleName);
+	}
+
+	/**
+	 * Prefix a given rule with a token multiple times
+	 *
+	 * @param ruleName
+	 *                The name of the rule to prefix
+	 * @param prefixToken
+	 *                The token to prefix to the rules
+	 * @param additionalProbability
+	 *                The additional probability of the tokens
+	 * @param numberOfTimes
+	 *                The number of times to prefix the token
+	 */
+	public void multiPrefixRule(final E ruleName, final E prefixToken, final int additionalProbability,
+			final int numberOfTimes) {
+		if (ruleName == null)
+			throw new NullPointerException("Rule name must not be null");
+		else if (prefixToken == null)
+			throw new NullPointerException("Prefix token must not be null");
+		else if (numberOfTimes < 1)
+			throw new IllegalArgumentException("Number of times to prefix must be positive.");
+
+		final WeightedRandom<IList<E>> rule = rules.get(ruleName);
+
+		final IList<IPair<Integer, IList<E>>> newResults = new FunctionalList<>();
+
+		rule.getValues().forEach((pair) -> {
+			final IList<IList<E>> newRule = new FunctionalList<>();
+
+			for (int i = 1; i <= numberOfTimes; i++) {
+				final IList<E> newCase = pair.merge((left, right) -> {
+					final IList<E> returnVal = new FunctionalList<>();
+
+					for (final E val : right.toIterable()) {
+						returnVal.add(val);
+					}
+
+					return returnVal;
+				});
+
+				for (int j = 1; j <= i; j++) {
+					newCase.prepend(prefixToken);
+				}
+
+				newRule.add(newCase);
+			}
+
+			newRule.forEach((list) -> {
+				final Integer currentProb = pair.merge((left, right) -> left);
+
+				newResults.add(new Pair<>(currentProb + additionalProbability, list));
+			});
+		});
+
+		newResults.forEach((pair) -> {
+			pair.doWith((left, right) -> {
+				addCase(ruleName, left, right);
+			});
+		});
+	}
+
+	/**
+	 * Create a series of alternatives for a rule by prefixing them with a
+	 * given token
+	 *
+	 * @param additionalProbability
+	 *                The amount to adjust the probability by
+	 * @param ruleName
+	 *                The name of the rule to prefix
+	 * @param prefixToken
+	 *                The token to prefix to the rule
+	 */
+	public void prefixRule(final E ruleName, final E prefixToken, final int additionalProbability) {
+		if (ruleName == null)
+			throw new NullPointerException("Rule name must not be null");
+		else if (prefixToken == null) throw new NullPointerException("Prefix token must not be null");
+
+		final WeightedRandom<IList<E>> rule = rules.get(ruleName);
+
+		final IList<IPair<Integer, IList<E>>> newResults = new FunctionalList<>();
+
+		rule.getValues().forEach((pair) -> {
+			final IList<E> newCase = pair.merge((left, right) -> {
+				final IList<E> returnVal = new FunctionalList<>();
+
+				for (final E val : right.toIterable()) {
+					returnVal.add(val);
+				}
+
+				return returnVal;
+			});
+
+			newCase.prepend(prefixToken);
+
+			newResults.add(new Pair<>(pair.merge((left, right) -> left) + additionalProbability, newCase));
+		});
+
+		newResults.forEach((pair) -> pair.doWith((left, right) -> addCase(ruleName, left, right)));
+	}
+
+	/**
+	 * Set the initial rule of the graphic
+	 *
+	 * @param initRule
+	 *                The initial rule of this grammar
+	 */
+	public void setInitialRule(final String initRule) {
+		this.initialRule = initRule;
+	}
+
+	/**
+	 * Suffix a token to a rule
+	 *
+	 * @param ruleName
+	 *                The rule to suffix
+	 * @param suffixToken
+	 *                The token to prefix to the rule
+	 * @param additionalProbability
+	 *                Additional probability of the prefixed rule
+	 */
+	public void suffixRule(final E ruleName, final E suffixToken, final int additionalProbability) {
+		if (ruleName == null)
+			throw new NullPointerException("Rule name must not be null");
+		else if (suffixToken == null) throw new NullPointerException("Prefix token must not be null");
+
+		final WeightedRandom<IList<E>> rule = rules.get(ruleName);
+
+		final IList<IPair<Integer, IList<E>>> newResults = new FunctionalList<>();
+
+		rule.getValues().forEach((par) -> {
+			final IList<E> newCase = par.merge((left, right) -> {
+				final IList<E> returnVal = new FunctionalList<>();
+
+				for (final E val : right.toIterable()) {
+					returnVal.add(val);
+				}
+
+				return returnVal;
+			});
+
+			newCase.add(suffixToken);
+
+			newResults.add(new Pair<>(par.merge((left, right) -> left) + additionalProbability, newCase));
+		});
+
+		newResults.forEach((pair) -> pair.doWith((left, right) -> addCase(ruleName, left, right)));
+	}
+}
diff --git a/base/src/main/java/bjc/utils/gen/WeightedRandom.java b/base/src/main/java/bjc/utils/gen/WeightedRandom.java
new file mode 100644
index 0000000..18225ef
--- /dev/null
+++ b/base/src/main/java/bjc/utils/gen/WeightedRandom.java
@@ -0,0 +1,112 @@
+package bjc.utils.gen;
+
+import java.util.Random;
+
+import bjc.utils.data.IHolder;
+import bjc.utils.data.IPair;
+import bjc.utils.data.Identity;
+import bjc.utils.funcdata.FunctionalList;
+import bjc.utils.funcdata.IList;
+
+/**
+ * Represents a random number generator where certain results are weighted more
+ * heavily than others.
+ *
+ * @author ben
+ *
+ * @param <E>
+ *                The type of values that are randomly selected.
+ */
+public class WeightedRandom<E> {
+	/*
+	 * The list of probabilities for each result
+	 */
+	private final IList<Integer> probabilities;
+
+	/*
+	 * The list of possible results to pick from
+	 */
+	private final IList<E> results;
+
+	/*
+	 * The source for any needed random numbers
+	 */
+	private final Random source;
+
+	private int totalChance;
+
+	/**
+	 * Create a new weighted random generator with the specified source of
+	 * randomness
+	 *
+	 * @param src
+	 *                The source of randomness to use.
+	 */
+	public WeightedRandom(final Random src) {
+		probabilities = new FunctionalList<>();
+		results = new FunctionalList<>();
+
+		if (src == null) throw new NullPointerException("Source of randomness must not be null");
+
+		source = src;
+	}
+
+	/**
+	 * Add a probability for a specific result to be given.
+	 *
+	 * @param chance
+	 *                The chance to get this result.
+	 * @param result
+	 *                The result to get when the chance comes up.
+	 */
+	public void addProbability(final int chance, final E result) {
+		probabilities.add(chance);
+		results.add(result);
+
+		totalChance += chance;
+	}
+
+	/**
+	 * Generate a weighted random value.
+	 *
+	 * @return A random value selected in a weighted fashion.
+	 */
+	public E generateValue() {
+		final IHolder<Integer> value = new Identity<>(source.nextInt(totalChance));
+		final IHolder<E> current = new Identity<>();
+		final IHolder<Boolean> picked = new Identity<>(true);
+
+		probabilities.forEachIndexed((index, probability) -> {
+			if (picked.unwrap(bool -> bool)) {
+				if (value.unwrap((number) -> number < probability)) {
+					current.transform((result) -> results.getByIndex(index));
+
+					picked.transform((bool) -> false);
+				} else {
+					value.transform((number) -> number - probability);
+				}
+			}
+		});
+
+		return current.unwrap((result) -> result);
+	}
+
+	/**
+	 * Return a list of values that can be generated by this generator
+	 *
+	 * @return A list of all the values that can be generated
+	 */
+	public IList<E> getResults() {
+		return results;
+	}
+
+	/**
+	 * Return a list containing values that can be generated paired with the
+	 * probability of those values being generated
+	 *
+	 * @return A list of pairs of values and value probabilities
+	 */
+	public IList<IPair<Integer, E>> getValues() {
+		return probabilities.pairWith(results);
+	}
+}