source: java/main/src/main/java/com/framsticks/core/Path.java @ 99

package com.framsticks.core;

import com.framsticks.params.AccessInterface;
import com.framsticks.params.CompositeParam;
import com.framsticks.params.Param;
import com.framsticks.util.FramsticksException;
import com.framsticks.util.dispatching.Dispatching;
import com.framsticks.util.dispatching.ExceptionResultHandler;
import com.framsticks.util.dispatching.IgnoreExceptionHandler;
import com.framsticks.util.lang.Pair;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.regex.Pattern;

import javax.annotation.Nonnull;
import javax.annotation.concurrent.Immutable;

import org.apache.commons.collections.ListUtils;

/**
 * @author Piotr Sniegowski
 */
@Immutable
public final class Path {
        // private final static Logger log = Logger.getLogger(Path.class.getName());

        final Tree tree;
        final String textual;
        final LinkedList<Node> nodes;

        protected static Object getKnownChild(Tree tree, AccessInterface access, CompositeParam param, ExceptionResultHandler handler) {
                Object child = access.get(param, Object.class);
                if (child == null) {
                        return null;
                }
                try {
                        tree.prepareAccess(param);
                        return child;
                } catch (FramsticksException e) {
                        handler.handle(e);
                }
                return null;
        }

        /**
         * @param tree
         * @param textual
         * @param nodes
         */
        Path(Tree tree, String textual, LinkedList<Node> nodes) {
                this.tree = tree;
                this.textual = textual;
                this.nodes = nodes;
        }

        public Path appendNode(Node node) {
                assert isResolved();
                return new PathBuilder().tree(tree).textual(textual + ((size() == 1) ? "" : "/") + node.getParam().getId()).add(nodes).add(node).finish();
        }

        public Path appendParam(CompositeParam param) {
                assert isResolved();
                return appendNode(new Node(tree, param, null));
        }

        public static class PathBuilder {

                Tree tree;
                String textual;
                final LinkedList<Node> nodes = new LinkedList<Node>();

                public Path finish() {
                        assert tree != null;
                        assert textual != null;
                        return new Path(tree, textual, nodes);
                }

                public PathBuilder()
                {
                }

                public PathBuilder tree(Tree tree) {
                        this.tree = tree;
                        return this;
                }

                public PathBuilder textual(String textual) {
                        this.textual = textual;
                        return this;
                }

                public PathBuilder add(List<Node> nodes) {
                        this.nodes.addAll(nodes);
                        return this;
                }

                public PathBuilder add(Node node) {
                        this.nodes.add(node);
                        return this;
                }

                public PathBuilder setLast(Object object) {
                        Node n = nodes.pollLast();
                        nodes.add(new Node(n.getTree(), n.getParam(), object));
                        return this;
                }

                public PathBuilder buildUpTo(List<Node> nodes, Node node) {
                        StringBuilder b = new StringBuilder();
                        boolean add = false;
                        for (Node n : nodes) {
                                this.nodes.add(n);
                                if (add) {
                                        b.append("/").append(n.getParam().getId());
                                }
                                add = true;
                                if (n == node) {
                                        break;
                                }
                        }
                        this.textual = (nodes.size() == 1) ? "/" : b.toString();
                        return this;
                }

                public static Iterator<String> splitPath(String path) {
                        List<String> list = new LinkedList<String>();
                        for (String s : path.split("/")) {
                                if (!s.isEmpty()) {
                                        list.add(s);
                                }
                        }
                        return list.iterator();
                }

                public PathBuilder resolve(@Nonnull Tree tree, String textual) {
                        return resolve(tree, textual, IgnoreExceptionHandler.getInstance());
                }

                public PathBuilder resolve(@Nonnull Tree tree, String textual, ExceptionResultHandler handler) {

                        assert nodes.isEmpty();
                        assert tree.isActive();
                        this.tree = tree;

                        Node current = tree.getAssignedRoot();
                        nodes.add(current);

                        StringBuilder b = new StringBuilder();
                        Iterator<String> i = splitPath(textual);
                        while (i.hasNext() && current.getObject() != null) {
                                AccessInterface access = TreeOperations.bindAccess(current);// tree.prepareAccess(current.getParam());
                                String e = i.next();
                                Param p = access.getParam(e);
                                if (p == null) {
                                        break;
                                }
                                if (!(p instanceof CompositeParam)) {
                                        throw new FramsticksException().msg("param is not a composite").arg("param", p).arg("tree", tree).arg("textual", textual).arg("access", access);
                                }
                                CompositeParam c = (CompositeParam) p;
                                b.append("/").append(e);
                                access.select(current.getObject());
                                current = new Node(current.getTree(), c, getKnownChild(tree, access, c, handler));
                                nodes.add(current);
                        }
                        this.textual = (nodes.size() == 1) ? "/" : b.toString();

                        return this;
                }
        }

        public static PathBuilder build() {
                return new PathBuilder();
        }

        public Path appendResolution(Object object) {
                assert !isResolved();
                Path result = new PathBuilder().textual(textual).tree(tree).add(nodes).setLast(object).finish();
                assert size() == result.size();
                return result;
        }

        public final Object getTopObject() {
                return getTop().getObject();
        }

        public final Node getTop() {
                return nodes.getLast();
        }

        public final Node getUnder() {
                assert nodes.size() >= 2;
                return nodes.get(nodes.size() - 2);
        }

        public final String getTextual() {
                return textual;
        }

        public String toString() {
                return tree + textual + (!isResolved() ? "!" : "");
        }

        public String getFullTextual() {
                return tree.getName() + textual;
        }

        public final int size() {
                assert Dispatching.isThreadSafe();
                return nodes.size();
        }

        public final boolean isResolved() {
                assert Dispatching.isThreadSafe();
                return getTop().getObject() != null;
        }

        public final boolean isResolved(String textual) {
                assert Dispatching.isThreadSafe();
                return isTheSame(textual) && isResolved();
        }

        public final boolean isTheSame(String textual) {
                assert Dispatching.isThreadSafe();
                return this.textual.equals(textual);
        }

        public final boolean isTheSameTextually(Path path) {
                assert Dispatching.isThreadSafe();
                return (tree == path.getTree()) && textual.equals(path.getTextual());
        }

        public final @Nonnull Tree getTree() {
                assert Dispatching.isThreadSafe();
                return tree;
        }

        public Path tryResolveIfNeeded() {
                if (isResolved()) {
                        return this;
                }
                return tryFindResolution();
        }

        /** Attach resolution at end, if available.
         *
         * @return Modified path, if resolution was available, this otherwise.
         */
        public Path tryFindResolution() {
                assert tree.isActive();
                assert !isResolved();
                if (size() == 1) {
                        return Path.build().resolve(tree, "/").finish();
                }
                Object child = getKnownChild(tree, TreeOperations.bindAccess(getUnder()), getTop().getParam(), IgnoreExceptionHandler.getInstance());
                if (child == null) {
                        return this;
                }
                return appendResolution(child);
        }


        public String getLastElement() {
                return getTop().getParam().getId();
        }

        public final boolean isOwner(Tree tree) {
                return this.tree == tree;
        }

        @SuppressWarnings("unchecked")
        public
        List<Node> getNodes() {
                return ListUtils.unmodifiableList(nodes);
        }

        public Path assureResolved() {
                if (!isResolved()) {
                        throw new FramsticksException().msg("path is not resolved").arg("path", this);
                }
                return this;
        }

        public static Path tryTo(@Nonnull Tree tree, String textual) {
                return Path.build().resolve(tree, textual).finish();
        }

        public static Path to(@Nonnull Tree tree, String textual) {
                Path path = tryTo(tree, textual);
                if (path.getTextual().equals(textual)) {
                        return path;
                }
                throw new FramsticksException().msg("failed to create path").arg("textual", textual).arg("result", path).arg("tree", tree);
        }

        public boolean isTheSameObjects(Path path) {
                if (tree != path.getTree()) {
                        return false;
                }
                if (size() != path.size()) {
                        return false;
                }
                if (!getTextual().equals(path.getTextual())) {
                        return false;
                }
                Iterator<Node> a = nodes.iterator();
                Iterator<Node> b = path.getNodes().iterator();
                while (a.hasNext()) {
                        assert b.hasNext();
                        if (a.next() != b.next()) {
                                return false;
                        }
                }
                return true;
        }

        public static final Pattern pathPattern = Pattern.compile("(\\/)|((\\/[^/]+)+)");

        public static boolean isValidString(String path) {
                return pathPattern.matcher(path).matches();
        }

        public static String appendString(String path, String element) {
                if (path.equals("/")) {
                        return path + element;
                }
                return path + "/" + element;
        }

        public static Pair<String, String> removeLastElement(String path) {
                assert isValidString(path);
                if (path.equals("/")) {
                        throw new FramsticksException().msg("cannot remove last element from root path");
                }
                int index = path.lastIndexOf('/');
                assert index != -1;
                if (index == 0) {
                        return new Pair<String, String>("/", path.substring(1));
                }
                return new Pair<String, String>(path.substring(0, index), path.substring(index + 1));
        }

        public static String validateString(String path) {
                if (!isValidString(path)) {
                        throw new FramsticksException().msg("path string validation failured").arg("path", path);
                }
                return path;
        }


        // public boolean isEmpty() {
        //      return nodes.isEmpty();
        // }
}