package net.sourceforge.pain.logic.fn;

import net.sourceforge.pain.data.type.*;

public final class SpaceFindFn {

	private SpaceFindFn() {
	}

	public static Interactive findByPrefix(Located actor, String namePrefix) {
		if (namePrefix == null || namePrefix.length() == 0) {
			return null;
		}

		String prefix = namePrefix.toLowerCase();
		if (namePrefix.equals("self")) {
			Interactive interactive = (Interactive) actor.getRole(Interactive.class);
			if (interactive != null) {
				return interactive;
			}
			// else we will look for this obj;
		}

		String mostSimilarName = null;
		Interactive result = null;
		for (Located obj = actor.getLocation().getFirstInSpace(); obj != null; obj = obj.getNextInSpace()) { // backstep lists are chained
			Interactive interactive = (Interactive) obj.getRole(Interactive.class);
			if (interactive == null) {
				continue;
			}
			String[] inames = interactive.getTargetList();
			for (int i = 0; i < inames.length; i++) {
				String iname = inames[i];
				if (iname.startsWith(prefix)) {
					if (iname.length() == prefix.length()) {
						return interactive; // found exact
					}
					if (mostSimilarName == null) {
						mostSimilarName = iname;
						result = interactive;
						continue;
					} else {
						if (isCloserTo(prefix, iname, mostSimilarName)) {
							mostSimilarName = iname;
							result = interactive;
						}
					}
				}
			}
		}

		return result;
	}

	/** starts check starting from target.length() character
	 *  @return IF name IS CLOSER TO target THAN thanName
	 * */
	public static boolean isCloserTo(String target, String name, String thenName) {
		for (int i = target.length(); true; i++) {
			if (name.length() == i) {
				return true;
			}
			if (thenName.length() == i) {
				return false;
			}
			char nc = name.charAt(i);
			char tnc = thenName.charAt(i);
			if (nc != tnc) {
				return nc < tnc;
			}
		}
	}
}