(refs #38)Add reverting wiki from history.

src/main/scala/app/WikiController.scala

@@ -6,12 +6,14 @@ import util.Directory._
 import util.ControlUtil._
 import jp.sf.amateras.scalatra.forms._
 import org.eclipse.jgit.api.Git
+import org.eclipse.jgit.api.errors.PatchApplyException
+import org.scalatra.FlashMapSupport
 
 class WikiController extends WikiControllerBase 
   with WikiService with RepositoryService with AccountService with ActivityService
   with CollaboratorsAuthenticator with ReferrerAuthenticator
 
-trait WikiControllerBase extends ControllerBase {
+trait WikiControllerBase extends ControllerBase with FlashMapSupport {
   self: WikiService with RepositoryService with ActivityService
     with CollaboratorsAuthenticator with ReferrerAuthenticator =>
 
@@ -58,18 +60,45 @@ trait WikiControllerBase extends ControllerBase {
   
   get("/:owner/:repository/wiki/:page/_compare/:commitId")(referrersOnly { repository =>
     val pageName = StringUtil.urlDecode(params("page"))
-    val commitId = params("commitId").split("\\.\\.\\.")
 
-    using(Git.open(getWikiRepositoryDir(repository.owner, repository.name))){ git =>
-      wiki.html.compare(Some(pageName), JGitUtil.getDiffs(git, commitId(0), commitId(1), true), repository)
+    defining(params("commitId").split("\\.\\.\\.")){ case Array(from, to) =>
+      using(Git.open(getWikiRepositoryDir(repository.owner, repository.name))){ git =>
+        wiki.html.compare(Some(pageName), from, to, JGitUtil.getDiffs(git, from, to, true), repository,
+          hasWritePermission(repository.owner, repository.name, context.loginAccount), flash.get("info"))
+      }
     }
   })
   
   get("/:owner/:repository/wiki/_compare/:commitId")(referrersOnly { repository =>
-    val commitId   = params("commitId").split("\\.\\.\\.")
+    defining(params("commitId").split("\\.\\.\\.")){ case Array(from, to) =>
+      using(Git.open(getWikiRepositoryDir(repository.owner, repository.name))){ git =>
+        wiki.html.compare(None, from, to, JGitUtil.getDiffs(git, from, to, true), repository,
+          hasWritePermission(repository.owner, repository.name, context.loginAccount), flash.get("info"))
+      }
+    }
+  })
 
-    using(Git.open(getWikiRepositoryDir(repository.owner, repository.name))){ git =>
-      wiki.html.compare(None, JGitUtil.getDiffs(git, commitId(0), commitId(1), true), repository)
+  get("/:owner/:repository/wiki/:page/_revert/:commitId")(collaboratorsOnly { repository =>
+    val pageName = StringUtil.urlDecode(params("page"))
+
+    defining(params("commitId").split("\\.\\.\\.")){ case Array(from, to) =>
+      if(revertWikiPage(repository.owner, repository.name, from, to, context.loginAccount.get, Some(pageName))){
+        redirect(s"/${repository.owner}/${repository.name}/wiki/${StringUtil.urlEncode(pageName)}")
+      } else {
+        flash += "info" -> "This patch was not able to be reversed."
+        redirect(s"/${repository.owner}/${repository.name}/wiki/${StringUtil.urlEncode(pageName)}/_compare/${from}...${to}")
+      }
+    }
+  })
+
+  get("/:owner/:repository/wiki/_revert/:commitId")(collaboratorsOnly { repository =>
+    defining(params("commitId").split("\\.\\.\\.")){ case Array(from, to) =>
+      if(revertWikiPage(repository.owner, repository.name, from, to, context.loginAccount.get, None)){
+        redirect(s"/${repository.owner}/${repository.name}/wiki/}")
+      } else {
+        flash += "info" -> "This patch was not able to be reversed."
+        redirect(s"/${repository.owner}/${repository.name}/wiki/_compare/${from}...${to}")
+      }
     }
   })
 

src/main/scala/service/WikiService.scala

@@ -4,8 +4,11 @@ import java.io.File
 import java.util.Date
 import org.eclipse.jgit.api.Git
 import org.apache.commons.io.FileUtils
-import util.{Directory, JGitUtil, LockUtil}
+import util.{StringUtil, Directory, JGitUtil, LockUtil}
 import util.ControlUtil._
+import org.eclipse.jgit.treewalk.CanonicalTreeParser
+import org.eclipse.jgit.diff.DiffFormatter
+import org.eclipse.jgit.api.errors.PatchApplyException
 
 object WikiService {
   
@@ -90,6 +93,52 @@ trait WikiService {
     }
   }
 
+  /**
+   * Reverts specified changes.
+   */
+  def revertWikiPage(owner: String, repository: String, from: String, to: String,
+                     committer: model.Account, pageName: Option[String]): Boolean = {
+    LockUtil.lock(s"${owner}/${repository}/wiki"){
+      using(Git.open(Directory.getWikiWorkDir(owner, repository))){ git =>
+        val reader = git.getRepository.newObjectReader
+        val oldTreeIter = new CanonicalTreeParser
+        oldTreeIter.reset(reader, git.getRepository.resolve(from + "^{tree}"))
+
+        val newTreeIter = new CanonicalTreeParser
+        newTreeIter.reset(reader, git.getRepository.resolve(to + "^{tree}"))
+
+        import scala.collection.JavaConverters._
+        val diffs = git.diff.setNewTree(oldTreeIter).setOldTree(newTreeIter).call.asScala.filter { diff =>
+          pageName match {
+            case Some(x) => diff.getNewPath == x + ".md"
+            case None    => true
+          }
+        }
+
+        val patch = using(new java.io.ByteArrayOutputStream()){ out =>
+          val formatter = new DiffFormatter(out)
+          formatter.setRepository(git.getRepository)
+          formatter.format(diffs.asJava)
+          new String(out.toByteArray, "UTF-8")
+        }
+
+        try {
+          git.apply.setPatch(new java.io.ByteArrayInputStream(patch.getBytes("UTF-8"))).call
+          git.add.addFilepattern(".").call
+          git.commit.setCommitter(committer.userName, committer.mailAddress).setMessage(pageName match {
+            case Some(x) => s"Revert ${from} ... ${to} on ${x}"
+            case None    => s"Revert ${from} ... ${to}"
+          }).call
+          git.push.call
+          true
+        } catch {
+          case ex: PatchApplyException => false
+        }
+      }
+    }
+  }
+
+
   /**
    * Save the wiki page.
    */

src/main/twirl/wiki/compare.scala.html

@@ -1,10 +1,15 @@
 @(pageName: Option[String],
+  from: String,
+  to: String,
   diffs: Seq[util.JGitUtil.DiffInfo],
-  repository: service.RepositoryService.RepositoryInfo)(implicit context: app.Context)
+  repository: service.RepositoryService.RepositoryInfo,
+  hasWritePermission: Boolean,
+  info: Option[Any])(implicit context: app.Context)
 @import context._
 @import view.helpers._
 @import org.eclipse.jgit.diff.DiffEntry.ChangeType
 @html.main(s"Compare Revisions - ${repository.owner}/${repository.name}", Some(repository)){
+  @helper.html.information(info)
   @html.header("wiki", repository)
   @tab("history", repository)
   <ul class="nav nav-tabs">
@@ -23,4 +28,13 @@
     </li>
   </ul>
   @helper.html.diff(diffs, repository, None, None, false)
+  @if(hasWritePermission){
+    <div>
+      @if(pageName.isDefined){
+        <a href="@url(repository)/wiki/@urlEncode(pageName)/_revert/@from...@to" class="btn">Revert Changes</a>
+      } else {
+        <a href="@url(repository)/wiki/_revert/@from...@to" class="btn">Revert Changes</a>
+      }
+    </div>
+  }
 }