/*
 * Copyright 2000-2009 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.intellij.images.fileTypes;

import com.intellij.lang.documentation.AbstractDocumentationProvider;
import com.intellij.openapi.project.DumbService;
import com.intellij.openapi.util.SystemInfo;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.openapi.vfs.VirtualFileWithId;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFileSystemItem;
import org.intellij.images.index.ImageInfoIndex;
import org.jetbrains.annotations.Nullable;

import java.net.URI;
import java.net.URISyntaxException;

/**
 * @author spleaner
 */
public class ImageDocumentationProvider extends AbstractDocumentationProvider {
  private static final int MAX_IMAGE_SIZE = 300;

  @Override
  public String generateDoc(PsiElement element, @Nullable PsiElement originalElement) {
    final String[] result = new String[] {null};

    if (element instanceof PsiFileSystemItem && !((PsiFileSystemItem)element).isDirectory()) {
      final VirtualFile file = ((PsiFileSystemItem)element).getVirtualFile();
      if (file instanceof VirtualFileWithId && !DumbService.isDumb(element.getProject())) {
        ImageInfoIndex.processValues(file, (file1, value) -> {
          int imageWidth = value.width;
          int imageHeight = value.height;

          int maxSize = Math.max(value.width, value.height);
          if (maxSize > MAX_IMAGE_SIZE) {
            double scaleFactor = (double)MAX_IMAGE_SIZE / (double)maxSize;
            imageWidth *= scaleFactor;
            imageHeight *= scaleFactor;
          }
          try {
            String path = file1.getPath();
            if (SystemInfo.isWindows) {
              path = "/" + path;
            }
            final String url = new URI("file", null, path, null).toString();
            result[0] = String.format("<html><body><img src=\"%s\" width=\"%s\" height=\"%s\"><p>%sx%s, %sbpp</p><body></html>", url, imageWidth,
                                 imageHeight, value.width, value.height, value.bpp);
          }
          catch (URISyntaxException ignored) {
            // nothing
          }
          return true;
        }, element.getProject());
      }
    }

    return result[0];
  }
}