Revert "Reuse Gerrit code for head update"

This reverts commit 1a1abe3ed37eccaf4e23df696180ff3c8e2dc923.

Reason for revert: The pull-replication needs specific logic on the ACLs which would not be compatible with the existing Gerrit's heads update command.

Change-Id: Icb82133909f48e3e7740ad4de7fc09a91166dbb0

src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/UpdateHeadAction.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/UpdateHeadAction.java b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/UpdateHeadAction.java
index ae9c072..4195435 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/UpdateHeadAction.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/replication/pull/api/UpdateHeadAction.java
@@ -14,28 +14,66 @@
 
 package com.googlesource.gerrit.plugins.replication.pull.api;
 
+import com.google.common.base.Strings;
+import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.extensions.api.projects.HeadInput;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.RefPermission;
 import com.google.gerrit.server.project.ProjectResource;
-import com.google.gerrit.server.restapi.project.SetHead;
 import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import com.googlesource.gerrit.plugins.replication.LocalFS;
+import com.googlesource.gerrit.plugins.replication.pull.GerritConfigOps;
+import java.util.Optional;
+import org.eclipse.jgit.transport.URIish;
 
+@Singleton
 public class UpdateHeadAction implements RestModifyView<ProjectResource, HeadInput> {
-
-  private final SetHead setHead;
+  private final GerritConfigOps gerritConfigOps;
+  private final PermissionBackend permissionBackend;
 
   @Inject
-  public UpdateHeadAction(SetHead setHead) {
-    this.setHead = setHead;
+  UpdateHeadAction(GerritConfigOps gerritConfigOps, PermissionBackend permissionBackend) {
+    this.gerritConfigOps = gerritConfigOps;
+    this.permissionBackend = permissionBackend;
   }
 
   @Override
-  public Response<?> apply(ProjectResource resource, HeadInput input)
+  public Response<?> apply(ProjectResource projectResource, HeadInput input)
       throws AuthException, BadRequestException, ResourceConflictException, Exception {
-    return setHead.apply(resource, input);
+    if (input == null || Strings.isNullOrEmpty(input.ref)) {
+      throw new BadRequestException("ref required");
+    }
+    String ref = RefNames.fullName(input.ref);
+
+    permissionBackend
+        .user(projectResource.getUser())
+        .project(projectResource.getNameKey())
+        .ref(ref)
+        .check(RefPermission.SET_HEAD);
+
+    // TODO: the .git suffix should not be added here, but rather it should be
+    //  dealt with by the caller, honouring the naming style from the
+    //  replication.config (Issue 15221)
+    Optional<URIish> maybeRepo =
+        gerritConfigOps.getGitRepositoryURI(String.format("%s.git", projectResource.getName()));
+
+    if (maybeRepo.isPresent()) {
+      if (new LocalFS(maybeRepo.get()).updateHead(projectResource.getNameKey(), ref)) {
+        return Response.ok(ref);
+      }
+      throw new UnprocessableEntityException(
+          String.format(
+              "Could not update HEAD of repo %s to ref %s", projectResource.getName(), ref));
+    }
+    throw new ResourceNotFoundException(
+        String.format("Could not compute URL for repo: %s", projectResource.getName()));
   }
 }