moderators can relocate forum topics

app/controllers/ForumPost.scala

@@ -108,6 +108,21 @@ final class ForumPost(env: Env) extends LilaController(env) with ForumController
               NoContent
   }
 
+  def relocate(id: ForumPostId) = SecureBody(_.ModerateForum) { ctx ?=> me ?=>
+    Found(postApi.getPost(id).flatMapz(postApi.viewOf)): post =>
+      forms.relocateTo
+        .bindFromRequest()
+        .value
+        .so: to =>
+          env.forum.topicApi
+            .relocate(post.topic.id, to)
+            .inject:
+              post.post.userId.foreach: op =>
+                val newUrl = routes.ForumTopic.show(to, post.topic.slug, 1).url
+                env.msg.api.systemPost(op, MsgPreset.forumRelocation(post.topic.name, newUrl))
+              Redirect(routes.ForumCateg.show(to)).flashSuccess
+  }
+
   def react(categId: ForumCategId, id: ForumPostId, reaction: String, v: Boolean) = Auth { _ ?=> me ?=>
     CategGrantWrite(categId):
       FoundSnip(postApi.react(categId, id, reaction, v)): post =>

conf/routes

@@ -598,15 +598,16 @@ GET   /kaladin                         controllers.Irwin.kaladin
 # Forum
 GET   /forum                           controllers.ForumCateg.index
 GET   /forum/search                    controllers.ForumPost.search(text ?= "", page: Int ?= 1)
-GET   /forum/:categId                     controllers.ForumCateg.show(categId: ForumCategId, page: Int ?= 1)
-GET   /forum/:categId/form           controllers.ForumTopic.form(categId: ForumCategId)
-POST  /forum/:categId/new            controllers.ForumTopic.create(categId: ForumCategId)
+GET   /forum/:categId                  controllers.ForumCateg.show(categId: ForumCategId, page: Int ?= 1)
+GET   /forum/:categId/form             controllers.ForumTopic.form(categId: ForumCategId)
+POST  /forum/:categId/new              controllers.ForumTopic.create(categId: ForumCategId)
 GET   /forum/participants/:topicId     controllers.ForumTopic.participants(topicId: ForumTopicId)
-GET   /forum/:categId/:slug          controllers.ForumTopic.show(categId: ForumCategId, slug, page: Int ?= 1)
-POST  /forum/:categId/:slug/close    controllers.ForumTopic.close(categId: ForumCategId, slug)
-POST  /forum/:categId/:slug/sticky   controllers.ForumTopic.sticky(categId: ForumCategId, slug)
-POST  /forum/:categId/:slug/new      controllers.ForumPost.create(categId: ForumCategId, slug, page: Int ?= 1)
+GET   /forum/:categId/:slug            controllers.ForumTopic.show(categId: ForumCategId, slug, page: Int ?= 1)
+POST  /forum/:categId/:slug/close      controllers.ForumTopic.close(categId: ForumCategId, slug)
+POST  /forum/:categId/:slug/sticky     controllers.ForumTopic.sticky(categId: ForumCategId, slug)
+POST  /forum/:categId/:slug/new        controllers.ForumPost.create(categId: ForumCategId, slug, page: Int ?= 1)
 POST  /forum/delete/:id                controllers.ForumPost.delete(id: ForumPostId)
+POST  /forum/relocate/:id              controllers.ForumPost.relocate(id: ForumPostId)
 POST  /forum/:categId/react/:id/:reaction/:v controllers.ForumPost.react(categId: ForumCategId, id: ForumPostId, reaction, v: Boolean)
 POST  /forum/post/:id                  controllers.ForumPost.edit(id: ForumPostId)
 GET   /forum/redirect/post/:id         controllers.ForumPost.redirect(id: ForumPostId)

modules/forum/src/main/ForumForm.scala

@@ -3,7 +3,7 @@ package lila.forum
 import play.api.data.*
 import play.api.data.Forms.*
 
-import lila.common.Form.cleanText
+import lila.common.Form.{ cleanText, into }
 import lila.common.Form.given
 
 final private[forum] class ForumForm(
@@ -42,6 +42,9 @@ final private[forum] class ForumForm(
   val deleteWithReason = Form:
     single("reason" -> optional(nonEmptyText))
 
+  val relocateTo = Form:
+    single("categ" -> nonEmptyText.into[ForumCategId])
+
   private def userTextMapping(inOwnTeam: Boolean, previousText: Option[String] = None)(using me: Me) =
     cleanText(minLength = 3, 10_000)
       .verifying(

modules/forum/src/main/ForumTopicApi.scala

@@ -39,11 +39,7 @@ final private class ForumTopicApi(
       .flatMapz: topic =>
         show(categId, slug, topic.lastPage(config.postMaxPerPage))
 
-  def show(
-      categId: ForumCategId,
-      slug: String,
-      page: Int
-  )(using
+  def show(categId: ForumCategId, slug: String, page: Int)(using
       NetDomain
   )(using me: Option[Me]): Fu[Option[(ForumCateg, ForumTopic, Paginator[ForumPost.WithFrag])]] =
     for
@@ -219,3 +215,9 @@ final private class ForumTopicApi(
               _ <- categRepo.coll.update
                 .one($id(cat.id), cat.withoutTopic(topic, lastPostId, lastPostIdTroll))
             yield ()
+
+  def relocate(topic: ForumTopicId, to: ForumCategId)(using Me): Funit =
+    for
+      _ <- topicRepo.coll.update.one($id(topic), $set("categId" -> to))
+      _ <- postRepo.coll.update.one($doc("topicId" -> topic), $set("categId" -> to))
+    yield ()

modules/forum/src/main/model.scala

@@ -31,11 +31,7 @@ case class TopicView(
   def name      = topic.name
   def createdAt = topic.createdAt
 
-case class PostView(
-    post: ForumPost,
-    topic: ForumTopic,
-    categ: ForumCateg
-):
+case class PostView(post: ForumPost, topic: ForumTopic, categ: ForumCateg):
   def show         = post.showUserIdOrAuthor + " @ " + topic.name + " - " + post.text.take(80)
   def logFormatted = "%s / %s#%s / %s".format(categ.name, topic.name, post.number, post.text)
 

modules/forum/src/main/ui/PostUi.scala

@@ -55,6 +55,14 @@ final class PostUi(helpers: Helpers, bits: ForumBits):
                   ).some
                 else
                   frag(
+                    (canModCateg && post.number == 1).option:
+                      a(
+                        cls      := "mod mod-relocate button button-empty",
+                        href     := routes.ForumPost.relocate(post.id),
+                        dataIcon := Icon.Forward,
+                        title    := "Relocate"
+                      )
+                    ,
                     if canModCateg || topic.isUblogAuthor(me) then
                       a(
                         cls      := "mod delete button button-empty",

modules/forum/src/main/ui/TopicUi.scala

@@ -167,7 +167,8 @@ final class TopicUi(helpers: Helpers, bits: ForumBits, postUi: PostUi)(
                   )
                 )
               ),
-              (canModCateg || ctx.me.exists(topic.isAuthor)).option(deleteModal)
+              (canModCateg || ctx.me.exists(topic.isAuthor)).option(deleteModal),
+              canModCateg.option(relocateModal(categ))
             )
           ),
           formWithCaptcha.map: (form, captcha) =>
@@ -253,3 +254,28 @@ final class TopicUi(helpers: Helpers, bits: ForumBits, postUi: PostUi)(
         )
       )
     )
+
+  private val relocateTo = List(
+    "general-chess-discussion" -> "General Chess Discussion",
+    "lichess-feedback"         -> "Lichess Feedback",
+    "game-analysis"            -> "Game Analysis",
+    "off-topic-discussion"     -> "Off-Topic Discussion"
+  )
+
+  private def relocateModal(from: lila.forum.ForumCateg) =
+    div(cls := "forum-relocate-modal none")(
+      p("Move the entire thread to another forum"),
+      st.form(method := "post", cls := "form3")(
+        st.select(
+          name := "categ",
+          cls  := "form-control"
+        )(
+          relocateTo.collect:
+            case (slug, name) if slug != from.id.value => st.option(value := slug)(name)
+        ),
+        form3.actions(
+          button(cls := "cancel button button-empty", tpe := "button")("Cancel"),
+          form3.submit(frag("Relocate the thread"))(cls := "button-red")
+        )
+      )
+    )

modules/msg/src/main/MsgPreset.scala

@@ -9,15 +9,20 @@ object MsgPreset:
 
   import lila.core.msg.{ MsgPreset as Msg }
 
+  private val baseUrl = "https://lichess.org"
+
   def maxFollow(username: UserName, max: Int) =
     Msg(
       name = "Follow limit reached!",
       text = s"""Sorry, you can't follow more than $max players on Lichess.
-To follow new players, you must first unfollow some on https://lichess.org/@/$username/following.
+To follow new players, you must first unfollow some on $baseUrl/@/$username/following.
 
 Thank you for your understanding."""
     )
 
+  def forumRelocation(title: String, newUrl: String) =
+    s"""A moderator has moved your post "$title" to a different subforum. You can find it here: $baseUrl$newUrl."""
+
   object forumDeletion:
 
     val presets = List(
@@ -30,12 +35,12 @@ Thank you for your understanding."""
 
     def byModerator = compose("A moderator")
 
-    def byTeamLeader(forumId: ForumCategId) = compose(s"A team leader of https://lichess.org/forum/$forumId")
+    def byTeamLeader(forumId: ForumCategId) = compose(s"A team leader of $baseUrl/forum/$forumId")
 
     def byBlogAuthor(user: UserName) = compose(by = s"The community blog author $user")
 
     private def compose(by: String)(reason: String, forumPost: String) =
-      s"""$by deleted the following of your posts for this reason: $reason. Please read Lichess' Forum-Etiquette: https://lichess.org/page/forum-etiquette
+      s"""$by deleted the following of your posts for this reason: $reason. Please read Lichess' Forum-Etiquette: $baseUrl/page/forum-etiquette
 ----
 $forumPost
     """

ui/bits/src/bits.forum.ts

@@ -26,6 +26,20 @@ site.load.then(() => {
         });
       return false;
     })
+    .on('click', 'a.mod-relocate', function (this: HTMLAnchorElement) {
+      const link = this;
+      site.dialog
+        .dom({
+          cash: $('.forum-relocate-modal'),
+          attrs: { view: { action: link.href } },
+        })
+        .then(dlg => {
+          $(dlg.view).find('form').attr('action', link.href);
+          $(dlg.view).find('form button.cancel').on('click', dlg.close);
+          dlg.showModal();
+        });
+      return false;
+    })
     .on('click', 'form.unsub button', function (this: HTMLButtonElement) {
       const form = $(this).parent().toggleClass('on off')[0] as HTMLFormElement;
       xhr.text(`${form.action}?unsub=${this.dataset.unsub}`, { method: 'post' });