fix: issue #7 rebuild media links to get gallery working again

lib/bds/desktop/shell_commands.ex

@@ -196,6 +196,14 @@ defmodule BDS.Desktop.ShellCommands do
     end)
   end
 
+  defp dispatch("rebuild_media_links", project, _params) do
+    queue_task(project, "rebuild_media_links", "Rebuild Media Links", "Maintenance", fn report ->
+      {:ok, result} = BDS.Media.rebuild_media_links(project.id, on_progress: report)
+      report.(1.0, "Media links rebuilt")
+      %{project_id: project.id, counts: %{media_links: result.links}}
+    end)
+  end
+
   defp dispatch("regenerate_missing_thumbnails", project, _params) do
     queue_task(
       project,

lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex

@@ -375,7 +375,8 @@
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_media_from_files"><%= dgettext("ui", "Rebuild Media From Files") %></button>
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_scripts_from_files"><%= dgettext("ui", "Rebuild Scripts From Files") %></button>
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_templates_from_files"><%= dgettext("ui", "Rebuild Templates From Files") %></button>
-            <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_post_links"><%= dgettext("ui", "Rebuild Links") %></button>
+            <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_post_links"><%= dgettext("ui", "Rebuild Post Links") %></button>
+            <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_media_links"><%= dgettext("ui", "Rebuild Media Links") %></button>
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="regenerate_missing_thumbnails"><%= dgettext("ui", "Regenerate Missing Thumbnails") %></button>
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="rebuild_embedding_index"><%= dgettext("ui", "Rebuild Embedding Index") %></button>
             <button class="secondary ui-button ui-button-secondary" type="button" phx-click="settings_shell_command" phx-value-action="open_data_folder"><%= dgettext("ui", "Open Data Folder") %></button>

lib/bds/media.ex

@@ -66,6 +66,12 @@ defmodule BDS.Media do
   defdelegate link_media_to_post(media_id, post_id), to: BDS.Media.Linking
   defdelegate unlink_media_from_post(media_id, post_id), to: BDS.Media.Linking
 
+  defdelegate rebuild_media_links(project_id), to: BDS.Media.Linking,
+    as: :rebuild_links_from_sidecars
+
+  defdelegate rebuild_media_links(project_id, opts), to: BDS.Media.Linking,
+    as: :rebuild_links_from_sidecars
+
   defdelegate rebuild_media_from_files(project_id), to: BDS.Media.Rebuilder
   defdelegate rebuild_media_from_files(project_id, opts), to: BDS.Media.Rebuilder
 

lib/bds/media/linking.ex

@@ -5,6 +5,13 @@ defmodule BDS.Media.Linking do
 
   import Ecto.Query
 
+  import BDS.Media.FileOps,
+    only: [
+      progress_callback: 1,
+      report_rebuild_progress: 4,
+      report_rebuild_started: 3
+    ]
+
   alias BDS.Media.Media
   alias BDS.Media.Sidecars
   alias BDS.Persistence
@@ -134,6 +141,45 @@ defmodule BDS.Media.Linking do
 
   def restore_post_links(_project_id, _media_id, _post_ids), do: :ok
 
+  @doc """
+  Rebuild the `post_media` junction for a project from every media sidecar's
+  `linkedPostIds`.
+
+  Media sidecars are the source of truth for gallery associations (matching the
+  old bDS `rebuildFromSidecars`). Existing project links are cleared and then
+  re-created from the on-disk sidecars, so galleries reflect the project's
+  metadata even if the junction table drifted or was never populated. Links to
+  posts that are not present in the database are skipped.
+  """
+  @spec rebuild_links_from_sidecars(String.t(), keyword()) ::
+          {:ok, %{media: non_neg_integer(), links: non_neg_integer()}}
+  def rebuild_links_from_sidecars(project_id, opts \\ []) when is_binary(project_id) do
+    project = Projects.get_project!(project_id)
+    on_progress = progress_callback(opts)
+
+    media_list =
+      Repo.all(from m in Media, where: m.project_id == ^project_id, order_by: [asc: m.id])
+
+    total = length(media_list)
+    :ok = report_rebuild_started(on_progress, total, "media links")
+
+    {_cleared, _} =
+      Repo.delete_all(from pm in PostMedia, where: pm.project_id == ^project_id)
+
+    media_list
+    |> Enum.with_index(1)
+    |> Enum.each(fn {media, index} ->
+      post_ids = Sidecars.read_linked_post_ids(project, media)
+      restore_post_links(project_id, media.id, post_ids)
+      :ok = report_rebuild_progress(on_progress, index, total, "media links")
+    end)
+
+    links =
+      Repo.aggregate(from(pm in PostMedia, where: pm.project_id == ^project_id), :count)
+
+    {:ok, %{media: total, links: links}}
+  end
+
   defp ensure_link(project_id, media_id, post_id) do
     already_linked? =
       Repo.exists?(

lib/bds/media/sidecars.ex

@@ -349,6 +349,29 @@ defmodule BDS.Media.Sidecars do
     |> File.exists?()
   end
 
+  @doc """
+  Read the `linkedPostIds` list persisted in a media item's canonical sidecar.
+
+  The media sidecar is the source of truth for gallery associations (matching
+  the old bDS `linkedPostIds` field). Returns `[]` when the sidecar is missing
+  or has no linked posts.
+  """
+  @spec read_linked_post_ids(BDS.Projects.Project.t(), Media.t()) :: [String.t()]
+  def read_linked_post_ids(project, %Media{} = media) do
+    sidecar_path = Path.join(Projects.project_data_dir(project), media.sidecar_path)
+
+    case parse_existing_canonical_sidecar(project, sidecar_path) do
+      {:ok, sidecar} ->
+        sidecar.fields
+        |> DocumentFields.get("linkedPostIds", [])
+        |> List.wrap()
+        |> Enum.filter(&is_binary/1)
+
+      {:error, _reason} ->
+        []
+    end
+  end
+
   defp parse_existing_canonical_sidecar(project, sidecar_path) do
     if File.exists?(sidecar_path) do
       parse_canonical_sidecar(project, sidecar_path)

priv/gettext/de/LC_MESSAGES/ui.po

@@ -1757,7 +1757,7 @@ msgid "Open"
 msgstr "Öffnen"
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr "Datenordner öffnen"
@@ -2049,16 +2049,11 @@ msgid "Rebuild Database"
 msgstr "Datenbank neu aufbauen"
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr "Embedding-Index neu aufbauen"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr "Links neu aufbauen"
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2116,7 +2111,7 @@ msgstr "Übersetzung aktualisieren"
 msgid "Regenerate Calendar"
 msgstr "Kalender neu erzeugen"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr "Fehlende Vorschaubilder neu erzeugen"
@@ -3533,3 +3528,13 @@ msgstr "Vorgeschlagene Tags"
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr "Website vollständig neu generieren"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format
+msgid "Rebuild Media Links"
+msgstr "Medien-Links neu aufbauen"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format
+msgid "Rebuild Post Links"
+msgstr "Beitrags-Links neu aufbauen"

priv/gettext/en/LC_MESSAGES/ui.po

@@ -1757,7 +1757,7 @@ msgid "Open"
 msgstr ""
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr ""
@@ -2049,16 +2049,11 @@ msgid "Rebuild Database"
 msgstr ""
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr ""
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr ""
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2116,7 +2111,7 @@ msgstr ""
 msgid "Regenerate Calendar"
 msgstr ""
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr ""
@@ -3533,3 +3528,13 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr ""
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Rebuild Media Links"
+msgstr ""
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format, fuzzy
+msgid "Rebuild Post Links"
+msgstr ""

priv/gettext/es/LC_MESSAGES/ui.po

@@ -1757,7 +1757,7 @@ msgid "Open"
 msgstr "Abrir"
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr "Abrir carpeta de datos"
@@ -2049,16 +2049,11 @@ msgid "Rebuild Database"
 msgstr "Reconstruir base de datos"
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr "Reconstruir índice de embeddings"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr "Reconstruir enlaces"
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2116,7 +2111,7 @@ msgstr "Actualizar traducción"
 msgid "Regenerate Calendar"
 msgstr "Regenerar calendario"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr "Regenerar miniaturas faltantes"
@@ -3533,3 +3528,13 @@ msgstr "Etiquetas sugeridas"
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr "Forzar la regeneración del sitio"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format
+msgid "Rebuild Media Links"
+msgstr "Reconstruir enlaces de medios"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format
+msgid "Rebuild Post Links"
+msgstr "Reconstruir enlaces de entradas"

priv/gettext/fr/LC_MESSAGES/ui.po

@@ -1757,7 +1757,7 @@ msgid "Open"
 msgstr "Ouvrir"
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr "Ouvrir le dossier de données"
@@ -2049,16 +2049,11 @@ msgid "Rebuild Database"
 msgstr "Reconstruire la base de données"
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr "Reconstruire l’index d’embeddings"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr "Reconstruire les liens"
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2116,7 +2111,7 @@ msgstr "Actualiser la traduction"
 msgid "Regenerate Calendar"
 msgstr "Régénérer le calendrier"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr "Régénérer les vignettes manquantes"
@@ -3533,3 +3528,13 @@ msgstr "Tags suggérés"
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr "Forcer la régénération du site"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format
+msgid "Rebuild Media Links"
+msgstr "Reconstruire les liens des médias"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format
+msgid "Rebuild Post Links"
+msgstr "Reconstruire les liens des articles"

priv/gettext/it/LC_MESSAGES/ui.po

@@ -1757,7 +1757,7 @@ msgid "Open"
 msgstr "Apri"
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr "Apri cartella dati"
@@ -2049,16 +2049,11 @@ msgid "Rebuild Database"
 msgstr "Ricostruisci database"
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr "Ricostruisci indice embeddings"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr "Ricostruisci i link"
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2116,7 +2111,7 @@ msgstr "Aggiorna traduzione"
 msgid "Regenerate Calendar"
 msgstr "Rigenera calendario"
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr "Rigenera miniature mancanti"
@@ -3533,3 +3528,13 @@ msgstr "Tag suggeriti"
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr "Forza la rigenerazione del sito"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format
+msgid "Rebuild Media Links"
+msgstr "Ricostruisci i link dei media"
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format
+msgid "Rebuild Post Links"
+msgstr "Ricostruisci i link degli articoli"

priv/gettext/ui.pot

@@ -1770,7 +1770,7 @@ msgid "Open"
 msgstr ""
 
 #: lib/bds/desktop/menu_bar.ex:154
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:382
 #, elixir-autogen, elixir-format
 msgid "Open Data Folder"
 msgstr ""
@@ -2062,16 +2062,11 @@ msgid "Rebuild Database"
 msgstr ""
 
 #: lib/bds/desktop/menu_bar.ex:184
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:381
 #, elixir-autogen, elixir-format
 msgid "Rebuild Embedding Index"
 msgstr ""
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
-#, elixir-autogen, elixir-format
-msgid "Rebuild Links"
-msgstr ""
-
 #: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:375
 #, elixir-autogen, elixir-format
 msgid "Rebuild Media From Files"
@@ -2129,7 +2124,7 @@ msgstr ""
 msgid "Regenerate Calendar"
 msgstr ""
 
-#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:380
 #, elixir-autogen, elixir-format
 msgid "Regenerate Missing Thumbnails"
 msgstr ""
@@ -3546,3 +3541,13 @@ msgstr ""
 #, elixir-autogen, elixir-format
 msgid "Force Render Site"
 msgstr ""
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:379
+#, elixir-autogen, elixir-format
+msgid "Rebuild Media Links"
+msgstr ""
+
+#: lib/bds/desktop/shell_live/settings_editor_html/settings_editor.html.heex:378
+#, elixir-autogen, elixir-format
+msgid "Rebuild Post Links"
+msgstr ""

test/bds/media/link_restore_fresh_test.exs

@@ -0,0 +1,62 @@
+defmodule BDS.Media.LinkRestoreFreshTest do
+  use ExUnit.Case, async: false
+
+  import Ecto.Query
+
+  alias BDS.Media
+  alias BDS.Media.Media, as: MediaRecord
+  alias BDS.Posts.PostMedia
+  alias BDS.Repo
+
+  setup do
+    :ok = Ecto.Adapters.SQL.Sandbox.checkout(Repo)
+    Ecto.Adapters.SQL.Sandbox.mode(Repo, {:shared, self()})
+    temp_dir = Path.join(System.tmp_dir!(), "bds-freshlink-#{System.unique_integer([:positive])}")
+    File.mkdir_p!(temp_dir)
+    on_exit(fn -> File.rm_rf(temp_dir) end)
+
+    {:ok, project} = BDS.Projects.create_project(%{name: "Fresh", data_path: temp_dir})
+    {:ok, _} = BDS.Metadata.update_project_metadata(project.id, %{main_language: "en"})
+
+    {:ok, post} =
+      BDS.Posts.create_post(%{
+        project_id: project.id,
+        title: "Gallery Post",
+        content: "[[gallery]]",
+        language: "en"
+      })
+
+    source = Path.join(temp_dir, "fresh.jpg")
+    File.write!(source, "fake jpeg")
+    {:ok, media} = Media.import_media(%{project_id: project.id, source_path: source})
+    {:ok, _} = Media.link_media_to_post(media.id, post.id)
+
+    %{project: project, post: post, media: media}
+  end
+
+  test "fresh media rebuild (media record gone, only files on disk) restores links", %{
+    project: project,
+    post: post,
+    media: media
+  } do
+    # Sidecar on disk should carry the link.
+    sidecar_path = Path.join(project.data_path, media.sidecar_path)
+    assert File.exists?(sidecar_path)
+    contents = File.read!(sidecar_path)
+    assert contents =~ "linkedPostIds"
+    assert contents =~ post.id
+
+    # Simulate a fresh DB: drop the media record AND its links entirely.
+    Repo.delete_all(from pm in PostMedia, where: pm.media_id == ^media.id)
+    Repo.delete_all(from m in MediaRecord, where: m.id == ^media.id)
+    assert Repo.aggregate(from(m in MediaRecord, where: m.id == ^media.id), :count) == 0
+
+    assert {:ok, _} = BDS.Media.rebuild_media_from_files(project.id)
+
+    # Media re-inserted from sidecar.
+    assert Repo.aggregate(from(m in MediaRecord, where: m.project_id == ^project.id), :count) == 1
+
+    # Link restored so the post's media list is populated again.
+    assert Repo.aggregate(from(pm in PostMedia, where: pm.post_id == ^post.id), :count) == 1
+  end
+end

test/bds/media/link_restore_test.exs

@@ -69,4 +69,51 @@ defmodule BDS.Media.LinkRestoreTest do
     assert {:ok, _} = BDS.Media.rebuild_media_from_files(project.id)
     assert link_count(post.id, media.id) == 1
   end
+
+  test "rebuild_media_links rebuilds gallery links from sidecars", %{
+    project: project,
+    post: post,
+    media: media
+  } do
+    # Simulate a project whose junction table was never populated even though
+    # the media sidecar references the post (the reported gallery regression).
+    Repo.delete_all(from pm in PostMedia, where: pm.media_id == ^media.id)
+    assert link_count(post.id, media.id) == 0
+
+    assert {:ok, %{media: 1, links: 1}} = BDS.Media.rebuild_media_links(project.id)
+
+    assert link_count(post.id, media.id) == 1
+  end
+
+  test "rebuild_media_links drops stale junction links not present in sidecars", %{
+    project: project,
+    post: post,
+    media: media
+  } do
+    {:ok, other_post} =
+      BDS.Posts.create_post(%{
+        project_id: project.id,
+        title: "Unrelated Post",
+        content: "no gallery here",
+        language: "en"
+      })
+
+    # A junction row that drifted from the sidecar: the media is linked to a
+    # post its sidecar does not reference. The sidecar is the source of truth,
+    # so rebuild must drop this link.
+    Repo.insert!(%PostMedia{
+      id: Ecto.UUID.generate(),
+      project_id: project.id,
+      post_id: other_post.id,
+      media_id: media.id,
+      sort_order: 5,
+      created_at: 0
+    })
+
+    assert {:ok, %{links: 1}} = BDS.Media.rebuild_media_links(project.id)
+
+    # The real (sidecar-backed) link survives, the drifted link is gone.
+    assert link_count(post.id, media.id) == 1
+    assert link_count(other_post.id, media.id) == 0
+  end
 end