/*
 * Copyright 2000-2013 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.jetbrains.plugins.javaFX.fxml.codeInsight.inspections;

import com.intellij.codeInsight.FileModificationService;
import com.intellij.codeInsight.daemon.QuickFixBundle;
import com.intellij.codeInspection.*;
import com.intellij.lang.ImportOptimizer;
import com.intellij.openapi.command.WriteCommandAction;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.psi.xml.XmlDocument;
import com.intellij.psi.xml.XmlFile;
import com.intellij.psi.xml.XmlProcessingInstruction;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.plugins.javaFX.fxml.JavaFxFileTypeFactory;
import org.jetbrains.plugins.javaFX.fxml.JavaFxPsiUtil;
import org.jetbrains.plugins.javaFX.fxml.codeInsight.JavaFxImportsOptimizer;

import java.util.*;

/**
 * User: anna
 * Date: 4/18/13
 */
public class JavaFxUnusedImportsInspection extends XmlSuppressableInspectionTool {
  @Nullable
  @Override
  public ProblemDescriptor[] checkFile(@NotNull PsiFile file, @NotNull InspectionManager manager, final boolean isOnTheFly) {
    if (!JavaFxFileTypeFactory.isFxml(file)) return null;
    final XmlDocument document = ((XmlFile)file).getDocument();
    if (document == null) return null;
    final Set<String> usedNames = new HashSet<String>();
    file.accept(new JavaFxImportsOptimizer.JavaFxUsedClassesVisitor() {
      @Override
      protected void appendClassName(String fqn) {
        usedNames.add(fqn);
        final String packageName = StringUtil.getPackageName(fqn);
        if (!StringUtil.isEmpty(packageName)) {
          usedNames.add(packageName);
        }
      }
    });

    final InspectionManager inspectionManager = InspectionManager.getInstance(file.getProject());

    final List<ProblemDescriptor> problems = new ArrayList<ProblemDescriptor>();
    final Collection<XmlProcessingInstruction> instructions =
      PsiTreeUtil.findChildrenOfType(document.getProlog(), XmlProcessingInstruction.class);
    final Map<String, XmlProcessingInstruction> targetProcessingInstructions = new LinkedHashMap<String, XmlProcessingInstruction>();
    for (XmlProcessingInstruction instruction : instructions) {
      final String target = JavaFxPsiUtil.getInstructionTarget("import", instruction);
      if (target != null) {
        targetProcessingInstructions.put(target, instruction);
      }
    }
    for (String target : targetProcessingInstructions.keySet()) {
      final XmlProcessingInstruction instruction = targetProcessingInstructions.get(target);
      if (target.endsWith(".*")) {
        if (!usedNames.contains(StringUtil.trimEnd(target, ".*"))) {
          problems.add(inspectionManager
                         .createProblemDescriptor(instruction, "Unused import", new JavaFxOptimizeImportsFix(), ProblemHighlightType.LIKE_UNUSED_SYMBOL, isOnTheFly));
        }
      }
      else if (!usedNames.contains(target) || targetProcessingInstructions.containsKey(StringUtil.getPackageName(target) + ".*")) {
        problems.add(inspectionManager
                       .createProblemDescriptor(instruction, "Unused import", new JavaFxOptimizeImportsFix(), ProblemHighlightType.LIKE_UNUSED_SYMBOL, isOnTheFly));
      }
    }
    return problems.isEmpty() ? null : problems.toArray(new ProblemDescriptor[problems.size()]);
  }

  private static class JavaFxOptimizeImportsFix implements LocalQuickFix {
    @NotNull
    @Override
    public String getName() {
      return QuickFixBundle.message("optimize.imports.fix");
    }

    @Override
    @NotNull
    public String getFamilyName() {
      return QuickFixBundle.message("optimize.imports.fix");
    }

    @Override
    public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {
      final PsiElement psiElement = descriptor.getPsiElement();
      if (psiElement == null) return;
      final PsiFile file = psiElement.getContainingFile();
      if (file == null || !JavaFxFileTypeFactory.isFxml(file)) return;
      if (!FileModificationService.getInstance().prepareFileForWrite(file)) return;
      ImportOptimizer optimizer = new JavaFxImportsOptimizer();
      final Runnable runnable = optimizer.processFile(file);
      new WriteCommandAction.Simple(project, getFamilyName(), file) {
        @Override
        protected void run() throws Throwable {
          runnable.run();
        }
      }.execute();
    }
  }
}