001/*
002 * Copyright 2010-2013 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.jetbrains.jet.lang.resolve.calls.tasks;
018
019import com.google.common.base.Predicate;
020import com.google.common.collect.Collections2;
021import com.google.common.collect.Lists;
022import com.google.common.collect.Sets;
023import org.jetbrains.annotations.NotNull;
024import org.jetbrains.annotations.Nullable;
025import org.jetbrains.jet.lang.descriptors.CallableDescriptor;
026import org.jetbrains.jet.lang.psi.JetPsiUtil;
027import org.jetbrains.jet.lang.psi.JetReferenceExpression;
028import org.jetbrains.jet.lang.resolve.calls.context.BasicCallResolutionContext;
029
030import java.util.Collection;
031import java.util.List;
032
033public class ResolutionTaskHolder<D extends CallableDescriptor, F extends D> {
034    private final JetReferenceExpression reference;
035    private final BasicCallResolutionContext basicCallResolutionContext;
036    private final PriorityProvider<ResolutionCandidate<D>> priorityProvider;
037    private final boolean isSafeCall;
038
039    private final Collection<Collection<ResolutionCandidate<D>>> candidatesList = Lists.newArrayList();
040
041    private List<ResolutionTask<D, F>> tasks = null;
042
043    public ResolutionTaskHolder(@NotNull JetReferenceExpression reference,
044            @NotNull BasicCallResolutionContext basicCallResolutionContext,
045            @NotNull PriorityProvider<ResolutionCandidate<D>> priorityProvider
046    ) {
047        this.reference = reference;
048        this.basicCallResolutionContext = basicCallResolutionContext;
049        this.priorityProvider = priorityProvider;
050        this.isSafeCall = JetPsiUtil.isSafeCall(basicCallResolutionContext.call);
051    }
052
053    public Collection<ResolutionCandidate<D>> setIsSafeCall(@NotNull Collection<ResolutionCandidate<D>> candidates) {
054        for (ResolutionCandidate<D> candidate : candidates) {
055            candidate.setSafeCall(isSafeCall);
056        }
057        return candidates;
058    }
059
060    public void addCandidates(@NotNull Collection<ResolutionCandidate<D>> candidates) {
061        if (!candidates.isEmpty()) {
062            candidatesList.add(setIsSafeCall(candidates));
063        }
064    }
065
066    public void addCandidates(@NotNull List<Collection<ResolutionCandidate<D>>> candidatesList) {
067        for (Collection<ResolutionCandidate<D>> candidates : candidatesList) {
068            addCandidates(candidates);
069        }
070    }
071
072    public List<ResolutionTask<D, F>> getTasks() {
073        if (tasks == null) {
074            tasks = Lists.newArrayList();
075
076            for (int priority = priorityProvider.getMaxPriority(); priority >= 0; priority--) {
077                final int finalPriority = priority;
078                for (Collection<ResolutionCandidate<D>> candidates : candidatesList) {
079                    Collection<ResolutionCandidate<D>> filteredCandidates = Collections2.filter(candidates, new Predicate<ResolutionCandidate<D>>() {
080                        @Override
081                        public boolean apply(@Nullable ResolutionCandidate<D> input) {
082                            return finalPriority == priorityProvider.getPriority(input);
083                        }
084                    });
085                    if (!filteredCandidates.isEmpty()) {
086                        tasks.add(new ResolutionTask<D, F>(filteredCandidates, reference, basicCallResolutionContext));
087                    }
088                }
089            }
090        }
091        return tasks;
092    }
093
094    public interface PriorityProvider<D> {
095        int getPriority(D candidate);
096
097        int getMaxPriority();
098    }
099}