Improve field query and fix mariadb's pickiness with parens

If no query is given, don't search with `like '%'`. MariaDB doesn't
want parens around columns in the GROUP BY clause.

modules/backend/src/main/scala/docspell/backend/ops/OCustomFields.scala

@@ -96,7 +96,10 @@ object OCustomFields {
 
       def findAll(coll: Ident, nameQuery: Option[String]): F[Vector[CustomFieldData]] =
         store.transact(
-          QCustomField.findAllLike(coll, nameQuery.map(WildcardString.apply).map(_.both))
+          QCustomField.findAllLike(
+            coll,
+            nameQuery.map(WildcardString.apply).flatMap(_.both)
+          )
         )
 
       def findById(coll: Ident, field: Ident): F[Option[CustomFieldData]] =

modules/backend/src/main/scala/docspell/backend/ops/WildcardString.scala

@@ -2,10 +2,11 @@ package docspell.backend.ops
 
 final class WildcardString private (str: String) {
 
-  def both: String =
-    if (str.startsWith("\"") && str.endsWith("\"")) str.drop(1).dropRight(1)
-    else if (str.startsWith("*") || str.endsWith("*")) str
-    else s"*$str*"
+  def both: Option[String] =
+    if (str.startsWith("\"") && str.endsWith("\"")) Some(str.drop(1).dropRight(1))
+    else if (str.startsWith("*") || str.endsWith("*")) Some(str)
+    else if (str.trim == "") None
+    else Some(s"*$str*")
 
 }
 object WildcardString {

modules/store/src/main/scala/docspell/store/impl/DoobieSyntax.scala

@@ -13,7 +13,7 @@ trait DoobieSyntax {
     groupBy(NonEmptyList.of(c0, cs: _*))
 
   def groupBy(cs: NonEmptyList[Column]): Fragment =
-    fr" GROUP BY (" ++ commas(cs.toList.map(_.f)) ++ fr")"
+    fr" GROUP BY " ++ commas(cs.toList.map(_.f))
 
   def coalesce(f0: Fragment, fs: Fragment*): Fragment =
     sql" coalesce(" ++ commas(f0 :: fs.toList) ++ sql") "

modules/store/src/main/scala/docspell/store/queries/QCustomField.scala

@@ -42,7 +42,7 @@ object QCustomField {
 
     val nameCond = nameQuery.map(QueryWildcard.apply) match {
       case Some(q) =>
-        or(fName.lowerLike(q), fLabel.lowerLike(q))
+        or(fName.lowerLike(q), and(fLabel.isNotNull, fLabel.lowerLike(q)))
       case None =>
         Fragment.empty
     }

modules/store/src/main/scala/docspell/store/queries/QueryWildcard.scala

@@ -11,7 +11,9 @@ object QueryWildcard {
       if (n.endsWith("*")) s"${n.dropRight(1)}%"
       else n
 
-    prefix(suffix(value))
+    val res = prefix(suffix(value))
+    if (res == "%%") "%"
+    else res
   }
 
 }

modules/store/src/test/scala/docspell/store/queries/QueryWildcardTest.scala

@@ -18,4 +18,9 @@ object QueryWildcardTest extends SimpleTestSuite {
     assertEquals("%name%", QueryWildcard("*name*"))
     assertEquals("%some other name%", QueryWildcard("*some other name*"))
   }
+
+  test("do not use multiple wildcards") {
+    assertEquals("%", QueryWildcard("**"))
+    assertEquals("%*%", QueryWildcard("***"))
+  }
 }