From 204afe9ca2e2c63fec76b1dc2e555a1614c5ae39 Mon Sep 17 00:00:00 2001
From: Nadya Zabrodina <Nadya.Zabrodina@jetbrains.com>
Date: Fri, 29 Apr 2016 12:58:41 +0300
Subject: [PATCH] [patch]: implement analyze and apply patch on the fly

---
 .../openapi/diff/impl/patch/PatchReader.java  | 35 +++++++++++++
 .../openapi/vcs/VcsApplicationSettings.java   |  1 +
 .../patch/ApplyPatchFromClipboardAction.java  | 52 +++++++++++++++++--
 .../changes/patch/PatchClipboardListener.java | 35 +++++++++++++
 4 files changed, 118 insertions(+), 5 deletions(-)
 create mode 100644 platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/PatchClipboardListener.java

diff --git a/platform/vcs-api/src/com/intellij/openapi/diff/impl/patch/PatchReader.java b/platform/vcs-api/src/com/intellij/openapi/diff/impl/patch/PatchReader.java
index c0ccbf4e8cc7..d62c74f14ef6 100644
--- a/platform/vcs-api/src/com/intellij/openapi/diff/impl/patch/PatchReader.java
+++ b/platform/vcs-api/src/com/intellij/openapi/diff/impl/patch/PatchReader.java
@@ -47,6 +47,9 @@ public class PatchReader {
 
   @NonNls private static final String CONTEXT_HUNK_PREFIX = "***************";
   @NonNls private static final String CONTEXT_FILE_PREFIX = "*** ";
+  @NonNls private static final String UNIFIED_BEFORE_HUNK_PREFIX = "--- ";
+  @NonNls private static final String UNIFIED_AFTER_HUNK_PREFIX = "+++ ";
+
   @NonNls private static final Pattern ourUnifiedHunkStartPattern = Pattern.compile("@@ -(\\d+)(,(\\d+))? \\+(\\d+)(,(\\d+))? @@.*");
   @NonNls private static final Pattern ourContextBeforeHunkStartPattern = Pattern.compile("\\*\\*\\* (\\d+),(\\d+) \\*\\*\\*\\*");
   @NonNls private static final Pattern ourContextAfterHunkStartPattern = Pattern.compile("--- (\\d+),(\\d+) ----");
@@ -629,4 +632,36 @@ public class PatchReader {
       return myHunkCount == 1 && myDeleted;
     }
   }
+
+  public static boolean isPatchContent(@Nullable String content) {
+    if (content == null) return false;
+    List<String> lines = LineTokenizer.tokenizeIntoList(content, false);
+    final ListIterator<String> iterator = lines.listIterator();
+    DiffFormat currentFormat = null;
+    while (iterator.hasNext()) {
+      String line = iterator.next();
+      if (line.startsWith(CONTEXT_HUNK_PREFIX)) {
+        currentFormat = DiffFormat.CONTEXT;
+      }
+      else if (currentFormat == DiffFormat.CONTEXT && ourContextBeforeHunkStartPattern.matcher(line).matches()) {
+        break;
+      }
+      else if (line.startsWith(UNIFIED_BEFORE_HUNK_PREFIX) && currentFormat == null) {
+        currentFormat = DiffFormat.UNIFIED;
+      }
+      else if (currentFormat == DiffFormat.UNIFIED && line.startsWith(UNIFIED_AFTER_HUNK_PREFIX)) break;
+    }
+    if (currentFormat == null) return false; // can't detect format
+    // check that contains at least one chunk
+    while (iterator.hasNext()) {
+      String line = iterator.next();
+      if (currentFormat == DiffFormat.CONTEXT) {
+        if (ourContextAfterHunkStartPattern.matcher(line).matches()) return true;
+      }
+      else {
+        if (ourUnifiedHunkStartPattern.matcher(line).matches()) return true;
+      }
+    }
+    return false;
+  }
 }
diff --git a/platform/vcs-api/src/com/intellij/openapi/vcs/VcsApplicationSettings.java b/platform/vcs-api/src/com/intellij/openapi/vcs/VcsApplicationSettings.java
index 67fc5fa7bad3..322f0d482e03 100644
--- a/platform/vcs-api/src/com/intellij/openapi/vcs/VcsApplicationSettings.java
+++ b/platform/vcs-api/src/com/intellij/openapi/vcs/VcsApplicationSettings.java
@@ -33,6 +33,7 @@ public class VcsApplicationSettings implements PersistentStateComponent<VcsAppli
   public boolean SHOW_WHITESPACES_IN_LST = false;
   public boolean SHOW_LST_GUTTER_MARKERS = true;
   public boolean SHOW_LST_WORD_DIFFERENCES = true;
+  public boolean DETECT_PATCH_ON_THE_FLY = true;
 
   public static VcsApplicationSettings getInstance() {
     return ServiceManager.getService(VcsApplicationSettings.class);
diff --git a/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/ApplyPatchFromClipboardAction.java b/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/ApplyPatchFromClipboardAction.java
index 915c86d87aa7..ae9c38948086 100644
--- a/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/ApplyPatchFromClipboardAction.java
+++ b/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/ApplyPatchFromClipboardAction.java
@@ -2,23 +2,39 @@ package com.intellij.openapi.vcs.changes.patch;
 
 import com.intellij.openapi.actionSystem.AnActionEvent;
 import com.intellij.openapi.actionSystem.CommonDataKeys;
+import com.intellij.openapi.application.ApplicationActivationListener;
+import com.intellij.openapi.application.ex.ApplicationManagerEx;
 import com.intellij.openapi.application.ex.ClipboardUtil;
 import com.intellij.openapi.fileEditor.FileDocumentManager;
 import com.intellij.openapi.project.DumbAwareAction;
 import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vcs.VcsApplicationSettings;
 import com.intellij.openapi.vcs.changes.ChangeListManager;
-import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.testFramework.LightVirtualFile;
+import com.intellij.util.ObjectUtils;
+import com.intellij.util.messages.MessageBusConnection;
+import org.jetbrains.annotations.NotNull;
 
+import javax.swing.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.KeyEvent;
 import java.util.Collections;
 
 public class ApplyPatchFromClipboardAction extends DumbAwareAction {
+  private static final PatchClipboardListener LISTENER = new PatchClipboardListener();
+
+  public ApplyPatchFromClipboardAction() {
+    MessageBusConnection connection = ApplicationManagerEx.getApplicationEx().getMessageBus().connect();
+    connection.subscribe(ApplicationActivationListener.TOPIC, LISTENER);
+  }
 
   @Override
   public void update(AnActionEvent e) {
     Project project = e.getData(CommonDataKeys.PROJECT);
     String text = ClipboardUtil.getTextInClipboard();
-    e.getPresentation().setEnabled(project != null && PatchFileUtil.isPatchContent(text));
+    // allow to apply from clipboard even we do not detect it as a patch, because during applying we parse content more precisely
+    e.getPresentation().setEnabled(project != null && text != null);
   }
 
   public void actionPerformed(AnActionEvent e) {
@@ -28,8 +44,34 @@ public class ApplyPatchFromClipboardAction extends DumbAwareAction {
 
     String clipboardText = ClipboardUtil.getTextInClipboard();
     assert clipboardText != null;
-    VirtualFile vFile = new LightVirtualFile("clipboardPatchFile", clipboardText);
-    new ApplyPatchDifferentiatedDialog(project, new ApplyPatchDefaultExecutor(project), Collections.emptyList(),
-                                       ApplyPatchMode.APPLY_PATCH_IN_MEMORY, vFile).show();
+    new MyApplyPatchFromClipboardDialog(project, clipboardText).show();
+  }
+
+  @NotNull
+  private static JCheckBox createAnalyzeOnTheFlyOptionPanel() {
+    final JCheckBox removeOptionCheckBox = new JCheckBox("Analyze and Apply Patch from Clipboard on the Fly");
+    removeOptionCheckBox.setMnemonic(KeyEvent.VK_L);
+    removeOptionCheckBox.setSelected(VcsApplicationSettings.getInstance().DETECT_PATCH_ON_THE_FLY);
+    removeOptionCheckBox.addActionListener(new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent e) {
+        VcsApplicationSettings.getInstance().DETECT_PATCH_ON_THE_FLY = removeOptionCheckBox.isSelected();
+      }
+    });
+    return removeOptionCheckBox;
+  }
+
+  public static class MyApplyPatchFromClipboardDialog extends ApplyPatchDifferentiatedDialog {
+    private static final JCheckBox FLY_OPTION_PANEL = createAnalyzeOnTheFlyOptionPanel();
+
+    public MyApplyPatchFromClipboardDialog(@NotNull Project project, @NotNull String clipboardText) {
+      super(project, new ApplyPatchDefaultExecutor(project), Collections.emptyList(), ApplyPatchMode.APPLY_PATCH_IN_MEMORY,
+            new LightVirtualFile("clipboardPatchFile", clipboardText));
+    }
+
+    @Override
+    protected JComponent createSouthPanel() {
+      return addDoNotShowCheckBox(ObjectUtils.assertNotNull(super.createSouthPanel()), FLY_OPTION_PANEL);
+    }
   }
 }
diff --git a/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/PatchClipboardListener.java b/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/PatchClipboardListener.java
new file mode 100644
index 000000000000..cc6e5e038207
--- /dev/null
+++ b/platform/vcs-impl/src/com/intellij/openapi/vcs/changes/patch/PatchClipboardListener.java
@@ -0,0 +1,35 @@
+/*
+ * Copyright 2000-2016 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.openapi.vcs.changes.patch;
+
+import com.intellij.openapi.application.ClipboardAnalyzeListener;
+import com.intellij.openapi.diff.impl.patch.PatchReader;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vcs.VcsApplicationSettings;
+import org.jetbrains.annotations.NotNull;
+
+public class PatchClipboardListener extends ClipboardAnalyzeListener {
+  @Override
+  protected void handle(@NotNull Project project, @NotNull String value) {
+    new ApplyPatchFromClipboardAction.MyApplyPatchFromClipboardDialog(project, value).show();
+  }
+
+  @Override
+  public boolean canHandle(@NotNull String value) {
+    if (!VcsApplicationSettings.getInstance().DETECT_PATCH_ON_THE_FLY) return false;
+    return PatchReader.isPatchContent(value);
+  }
+}