/*
 * 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 com.intellij.coldFusion.UI.editorActions.completionProviders;

import com.intellij.codeInsight.completion.CompletionParameters;
import com.intellij.codeInsight.completion.CompletionProvider;
import com.intellij.codeInsight.completion.CompletionResultSet;
import com.intellij.codeInsight.lookup.LookupElementBuilder;
import com.intellij.coldFusion.model.CfmlUtil;
import com.intellij.coldFusion.model.files.CfmlFileViewProvider;
import com.intellij.coldFusion.model.psi.CfmlImport;
import com.intellij.coldFusion.model.psi.stubs.CfmlIndex;
import com.intellij.openapi.util.io.FileUtil;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.PsiFile;
import com.intellij.psi.util.PsiTreeUtil;
import com.intellij.util.Function;
import com.intellij.util.ProcessingContext;
import com.intellij.util.containers.ContainerUtil;
import gnu.trove.THashSet;
import org.jetbrains.annotations.NotNull;

import java.util.Set;

class CfmlTagNamesCompletionProvider extends CompletionProvider<CompletionParameters> {
  public void addCompletions(@NotNull final CompletionParameters parameters,
                             final ProcessingContext context,
                             @NotNull final CompletionResultSet result) {
    if (!(parameters.getOriginalFile().getViewProvider() instanceof CfmlFileViewProvider)) {
      return;
    }

    for (String s : CfmlUtil.getTagList(parameters.getPosition().getProject())) {
      result.addElement(LookupElementBuilder.create(s).withCaseSensitivity(false));
    }

    CfmlImport[] imports = PsiTreeUtil.getChildrenOfType(parameters.getOriginalFile(), CfmlImport.class);
    if (imports == null) {
      return;
    }
    for (CfmlImport cfmlImport : imports) {
      final String prefix = cfmlImport.getPrefix();
      if (prefix != null) {
        addCompletionsFromDirectory(result, parameters, cfmlImport.getImportString(), prefix);
      }
    }
  }

  private void addCompletionsFromDirectory(CompletionResultSet result, CompletionParameters parameters, String libtag, String prefix) {
    final PsiFile originalFile = parameters.getOriginalFile();
    final VirtualFile folder = CfmlUtil.findFileByLibTag(originalFile, libtag);
    if (folder != null && folder.isDirectory()) {
      final Set<String> names = new THashSet<>(CfmlIndex.getInstance(originalFile.getProject()).getAllComponentsNames());
      names.retainAll(ContainerUtil.map(folder.getChildren(), virtualFile -> FileUtil.getNameWithoutExtension(virtualFile.getName()).toLowerCase()));
      for (String componentName : names) {
        result.addElement(LookupElementBuilder.create(prefix + ':' + componentName).withCaseSensitivity(false));
      }
    }
  }
}