/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 hsz Jakub Chrzanowski <jakub@hsz.mobi>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package mobi.hsz.idea.latex.reference;

import com.intellij.psi.*;
import com.intellij.psi.impl.source.resolve.reference.impl.providers.FileReferenceSet;
import com.intellij.util.ProcessingContext;
import mobi.hsz.idea.latex.psi.LatexArgument;
import mobi.hsz.idea.latex.psi.LatexFile;
import mobi.hsz.idea.latex.psi.LatexInstruction;
import mobi.hsz.idea.latex.psi.impl.LatexInstructionExtImpl;
import org.jetbrains.annotations.NotNull;

import java.util.Arrays;

import static com.intellij.patterns.PlatformPatterns.psiElement;
import static com.intellij.patterns.PlatformPatterns.psiFile;

/**
 * PSI elements references contributor.
 *
 * @author Jakub Chrzanowski <jakub@hsz.mobi>
 * @since 0.3
 */
public class LatexReferenceContributor extends PsiReferenceContributor {

    /**
     * Registers new references provider for PSI element.
     *
     * @param psiReferenceRegistrar reference provider
     */
    @Override
    public void registerReferenceProviders(@NotNull PsiReferenceRegistrar psiReferenceRegistrar) {
        psiReferenceRegistrar.registerReferenceProvider(psiElement().inFile(psiFile(LatexFile.class)), new LatexReferenceProvider());
    }

    /** Reference provider definition.  */
    private static class LatexReferenceProvider extends PsiReferenceProvider {
        private static final String[] IDENTIFIERS = {"\\input", "\\include", "\\includeonly"};

        /**
         * Returns references for given @{link PsiElement}.
         *
         * @param psiElement        current element
         * @param processingContext context
         * @return {@link PsiReference} list
         */
        @NotNull
        @Override
        public PsiReference[] getReferencesByElement(@NotNull PsiElement psiElement, @NotNull ProcessingContext processingContext) {
            if (psiElement instanceof LatexInstruction) {
                LatexInstructionExtImpl instruction = (LatexInstructionExtImpl) psiElement;
                String identifier = instruction.getIdentifier().getText();
                if (Arrays.asList(IDENTIFIERS).contains(identifier)) {
                    LatexArgument arg = instruction.getArgument();
                    if (arg != null && arg.getValue() != null) {
                        return new FileReferenceSet(arg.getValue(), instruction, arg.getStartOffsetInParent() + 1, this, true).getAllReferences();
                    }
                }
            }
            return PsiReference.EMPTY_ARRAY;
        }
    }

}
