Refactoring solr/fts migration

When re-indexing everything, skip intermediate populating the index
and do this as the very last step.

Parameterize adding new fields by their language.

modules/joex/src/main/scala/docspell/joex/fts/FtsWork.scala

@@ -14,16 +14,26 @@ object FtsWork {
   def apply[F[_]](f: FtsContext[F] => F[Unit]): FtsWork[F] =
     Kleisli(f)
 
-  def allInitializeTasks[F[_]: Monad]: FtsWork[F] =
-    FtsWork[F](_ => ().pure[F]).tap[FtsContext[F]].flatMap { ctx =>
-      NonEmptyList.fromList(ctx.fts.initialize.map(fm => from[F](fm.task))) match {
+  /** Runs all migration tasks unconditionally and inserts all data as last step. */
+  def reInitializeTasks[F[_]: Monad]: FtsWork[F] =
+    FtsWork { ctx =>
+      val migrations =
+        ctx.fts.initialize.map(fm => fm.changeResult(_ => FtsMigration.Result.workDone))
+
+      NonEmptyList.fromList(migrations) match {
         case Some(nel) =>
-          nel.reduce(semigroup[F])
+          nel
+            .map(fm => from[F](fm.task))
+            .append(insertAll[F](None))
+            .reduce(semigroup[F])
+            .run(ctx)
         case None =>
-          FtsWork[F](_ => ().pure[F])
+          ().pure[F]
       }
     }
 
+  /**
+    */
   def from[F[_]: FlatMap: Applicative](t: F[FtsMigration.Result]): FtsWork[F] =
     Kleisli.liftF(t).flatMap(transformResult[F])
 

modules/joex/src/main/scala/docspell/joex/fts/Migration.scala

@@ -11,6 +11,11 @@ import docspell.joex.Config
 import docspell.store.records.RFtsMigration
 import docspell.store.{AddResult, Store}
 
+/** Migrating the index from the previous version to this version.
+  *
+  * The sql database stores the outcome of a migration task. If this
+  * task has already been applied, it is skipped.
+  */
 case class Migration[F[_]](
     version: Int,
     engine: Ident,

modules/joex/src/main/scala/docspell/joex/fts/ReIndexTask.scala

@@ -46,6 +46,6 @@ object ReIndexTask {
               FtsWork.log[F](_.info("Clearing data failed. Continue re-indexing."))
             ) ++
             FtsWork.log[F](_.info("Running index initialize")) ++
-            FtsWork.allInitializeTasks[F]
+            FtsWork.reInitializeTasks[F]
       })
 }

modules/joex/src/main/scala/docspell/joex/fts/package.scala

@@ -4,6 +4,9 @@ import cats.data.Kleisli
 
 package object fts {
 
+  /** Some work that must be done to advance the schema of the fulltext
+    * index.
+    */
   type FtsWork[F[_]] = Kleisli[F, FtsContext[F], Unit]
 
 }