613: Added possibility to compare overridden template with the original one

resources/META-INF/plugin.xml

@@ -130,6 +130,9 @@
         <action id="MagentoInjectConstructorArgumentAction.Menu" class="com.magento.idea.magento2plugin.actions.generation.InjectConstructorArgumentAction">
             <add-to-group group-id="EditorPopupMenu"/>
         </action>
+        <action id="MagentoCompareTemplate.Menu" class="com.magento.idea.magento2plugin.actions.comparator.CompareTemplateAction">
+            <add-to-group group-id="EditorPopupMenu"/>
+        </action>
 
         <action id="CopyMagentoPath"
                 class="com.magento.idea.magento2plugin.actions.CopyMagentoPath"

src/com/magento/idea/magento2plugin/actions/comparator/CompareTemplateAction.java

@@ -0,0 +1,142 @@
+/*
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+package com.magento.idea.magento2plugin.actions.comparator;
+
+import com.intellij.diff.DiffDialogHints;
+import com.intellij.diff.DiffManager;
+import com.intellij.diff.chains.DiffRequestChain;
+import com.intellij.openapi.actionSystem.AnAction;
+import com.intellij.openapi.actionSystem.AnActionEvent;
+import com.intellij.openapi.actionSystem.PlatformDataKeys;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.VfsUtil;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.psi.PsiDirectory;
+import com.intellij.psi.PsiFile;
+import com.magento.idea.magento2plugin.MagentoIcons;
+import com.magento.idea.magento2plugin.actions.comparator.util.DiffRequestChainUtil;
+import com.magento.idea.magento2plugin.indexes.ModuleIndex;
+import com.magento.idea.magento2plugin.magento.packages.Areas;
+import com.magento.idea.magento2plugin.project.Settings;
+import com.magento.idea.magento2plugin.util.magento.GetModuleNameByDirectoryUtil;
+import com.magento.idea.magento2plugin.util.magento.area.AreaResolverUtil;
+import java.nio.file.Path;
+import org.apache.commons.lang3.StringUtils;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class CompareTemplateAction extends AnAction {
+
+    public static final String ACTION_NAME = "Compare overridden template with the original one";
+    public static final String ACTION_DESCRIPTION = "The Magento 2 overridden template comparing";
+
+    private static final String PHTML_EXTENSION = "phtml";
+    protected VirtualFile selectedFile;
+    protected VirtualFile originalFile;
+
+    /**
+     * Compare template action constructor.
+     */
+    public CompareTemplateAction() {
+        super(ACTION_NAME, ACTION_DESCRIPTION, MagentoIcons.MODULE);
+    }
+
+    /**
+     * Updates the state of action.
+     *
+     * @param event AnActionEvent
+     */
+    @SuppressWarnings("PMD.NPathComplexity")
+    @Override
+    public void update(final @NotNull AnActionEvent event) {
+        setStatus(event, false);
+        final Project project = event.getData(PlatformDataKeys.PROJECT);
+
+        if (project == null) {
+            return;
+        }
+
+        if (!Settings.isEnabled(project)) {
+            return;
+        }
+        final PsiFile psiFile = event.getData(PlatformDataKeys.PSI_FILE);
+
+        if (psiFile == null) {
+            return;
+        }
+        final VirtualFile targetFileCandidate = psiFile.getVirtualFile();
+
+        if (targetFileCandidate == null) {
+            return;
+        }
+
+        if (!PHTML_EXTENSION.equals(targetFileCandidate.getExtension())) {
+            return;
+        }
+        final Areas area = AreaResolverUtil.getForFileInCustomTheme(targetFileCandidate);
+
+        if (area == null) {
+            return;
+        }
+        final String originalModuleName = getOriginalModuleName(project, psiFile);
+        final PsiDirectory originalModuleDirectory =
+                new ModuleIndex(project).getModuleDirectoryByModuleName(originalModuleName);
+
+        if (originalModuleDirectory == null) {
+            return;
+        }
+        final String originalFilePath = originalModuleDirectory.getVirtualFile().getPath()
+                + "/view/"
+                + area
+                + StringUtils.substringAfter(targetFileCandidate.getPath(), originalModuleName);
+
+        final VirtualFile origFileCandidate = VfsUtil.findFile(Path.of(originalFilePath), false);
+
+        if (origFileCandidate == null) {
+            return;
+        }
+        selectedFile = targetFileCandidate;
+        originalFile = origFileCandidate;
+        this.setStatus(event, true);
+    }
+
+    @Override
+    public void actionPerformed(final @NotNull AnActionEvent event) {
+        final Project project = event.getProject();
+
+        if (project == null || selectedFile == null || originalFile == null) {
+            return;
+        }
+        final DiffRequestChain chain = DiffRequestChainUtil.createMutableChain(
+                project,
+                selectedFile,
+                originalFile
+        );
+
+        if (chain == null) {
+            return;
+        }
+        DiffManager.getInstance().showDiff(
+                project,
+                chain,
+                DiffDialogHints.DEFAULT
+        );
+    }
+
+    private @Nullable String getOriginalModuleName(
+            final @NotNull Project project,
+            final @NotNull PsiFile psiFile
+    ) {
+        final PsiDirectory directory = psiFile.getContainingDirectory();
+
+        return GetModuleNameByDirectoryUtil.execute(directory, project);
+    }
+
+    private void setStatus(final AnActionEvent event, final boolean status) {
+        event.getPresentation().setVisible(status);
+        event.getPresentation().setEnabled(status);
+    }
+}

src/com/magento/idea/magento2plugin/actions/comparator/util/DiffRequestChainUtil.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+package com.magento.idea.magento2plugin.actions.comparator.util;
+
+import com.intellij.diff.DiffContentFactory;
+import com.intellij.diff.DiffRequestFactory;
+import com.intellij.diff.actions.BlankDiffWindowUtil;
+import com.intellij.diff.actions.impl.MutableDiffRequestChain;
+import com.intellij.diff.contents.DiffContent;
+import com.intellij.diff.contents.DocumentContent;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.VirtualFile;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public final class DiffRequestChainUtil {
+
+    private DiffRequestChainUtil() {}
+
+    /**
+     * Create mutable chain for files comparing.
+     *
+     * @param project Project
+     * @param targetFile VirtualFile
+     * @param baseFile VirtualFile
+     *
+     * @return MutableDiffRequestChain
+     */
+    public static @Nullable MutableDiffRequestChain createMutableChain(
+            final @NotNull Project project,
+            final @NotNull VirtualFile targetFile,
+            final @NotNull VirtualFile baseFile
+    ) {
+        final DiffContentFactory contentFactory = DiffContentFactory.getInstance();
+        final DiffContent targetContent = contentFactory.create(project, targetFile);
+        final DiffContent baseContent = contentFactory.create(project, baseFile);
+
+        if (!(targetContent instanceof DocumentContent)
+                || !(baseContent instanceof DocumentContent)) {
+            return null;
+        }
+
+        final MutableDiffRequestChain chain = BlankDiffWindowUtil.createBlankDiffRequestChain(
+                (DocumentContent) targetContent,
+                (DocumentContent) baseContent,
+                null
+        );
+        chain.setWindowTitle(DiffRequestFactory.getInstance().getTitle(targetFile, baseFile));
+
+        return chain;
+    }
+}

src/com/magento/idea/magento2plugin/indexes/ModuleIndex.java

@@ -12,6 +12,7 @@
 import com.intellij.psi.PsiDirectory;
 import com.intellij.psi.PsiManager;
 import com.intellij.psi.search.GlobalSearchScope;
+import com.intellij.util.SlowOperations;
 import com.intellij.util.indexing.FileBasedIndex;
 import com.jetbrains.php.lang.PhpFileType;
 import com.magento.idea.magento2plugin.magento.packages.Package;
@@ -116,6 +117,7 @@ private List<String> getNames(
      * Returns PSI directory of the certain module.
      *
      * @param moduleName String
+     *
      * @return PsiDirectory
      */
     public @Nullable PsiDirectory getModuleDirectoryByModuleName(final String moduleName) {
@@ -124,14 +126,20 @@ private List<String> getNames(
         }
         final FileBasedIndex index = FileBasedIndex
                 .getInstance();
-
-        final Collection<VirtualFile> files = index.getContainingFiles(
-                ModuleNameIndex.KEY,
-                moduleName,
-                GlobalSearchScope.getScopeRestrictedByFileTypes(
-                    GlobalSearchScope.allScope(project),
-                    PhpFileType.INSTANCE
-            ));
+        final Collection<VirtualFile> files = new ArrayList<>();
+
+        SlowOperations.allowSlowOperations(() -> {
+            files.addAll(
+                    index.getContainingFiles(
+                            ModuleNameIndex.KEY,
+                            moduleName,
+                            GlobalSearchScope.getScopeRestrictedByFileTypes(
+                                    GlobalSearchScope.allScope(project),
+                                    PhpFileType.INSTANCE
+                            )
+                    )
+            );
+        });
 
         if (files.isEmpty()) {
             return null;

src/com/magento/idea/magento2plugin/util/magento/area/AreaResolverUtil.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+package com.magento.idea.magento2plugin.util.magento.area;
+
+import com.intellij.openapi.vfs.VirtualFile;
+import com.magento.idea.magento2plugin.magento.packages.Areas;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public final class AreaResolverUtil {
+
+    private static final String CUSTOM_THEME_AREA = "\\/design\\/(adminhtml|frontend)\\/";
+    private static final String MODULE_AREA =
+            "\\/view\\/(adminhtml|frontend|base|crontab|webapi_rest|webapi_soap|graphql)\\/";
+
+    private AreaResolverUtil() {}
+
+    /**
+     * Get Magento 2 area for the specified file (file should be in the custom theme).
+     *
+     * @param virtualFile VirtualFile
+     *
+     * @return Areas or null if file does not belong to the custom (editable) theme.
+     */
+    public static @Nullable Areas getForFileInCustomTheme(final @NotNull VirtualFile virtualFile) {
+        return getArea(virtualFile.getPath(), CUSTOM_THEME_AREA);
+    }
+
+    /**
+     * Get Magento 2 area for the specified file (file should be in the Magento 2 module).
+     *
+     * @param virtualFile VirtualFile
+     *
+     * @return Areas or null if file does not belong to the Magento 2 module.
+     */
+    public static @Nullable Areas getForFileInModule(final @NotNull VirtualFile virtualFile) {
+        return getArea(virtualFile.getPath(), MODULE_AREA);
+    }
+
+    private static @Nullable Areas getArea(
+            final @NotNull String filePath,
+            final @NotNull String searchingRegex
+    ) {
+        final Pattern pattern = Pattern.compile(searchingRegex);
+        final Matcher matcher = pattern.matcher(filePath);
+        String areaName = null;
+
+        if (matcher.find()) {
+            areaName =  matcher.group(1);
+        }
+
+        return areaName == null ? null : Areas.getAreaByString(areaName);
+    }
+}