fix substring using inline

Author: fupelaqu

es6/sql-bridge/src/test/scala/app/softnetwork/elastic/sql/SQLQuerySpec.scala

@@ -2362,7 +2362,7 @@ class SQLQuerySpec extends AnyFlatSpec with Matchers {
       |    "substr": {
       |      "script": {
       |        "lang": "painless",
-      |        "source": "(def arg0 = (!doc.containsKey('identifier2') || doc['identifier2'].empty ? null : doc['identifier2'].value); (arg0 == null) ? null :  def _start = (1 - 1); def _end = _start + 3; (_start < 0 || _end > arg0.length()) ? null : arg0.substring(_start, _end)         )"
+      |        "source": "(def arg0 = (!doc.containsKey('identifier2') || doc['identifier2'].empty ? null : doc['identifier2'].value); (arg0 == null) ? null : ((1 - 1) < 0 || (1 - 1 + 3) > arg0.length()) ? null : arg0.substring((1 - 1), (1 - 1 + 3)))"
       |      }
       |    },
       |    "trim": {
@@ -2392,6 +2392,7 @@ class SQLQuerySpec extends AnyFlatSpec with Matchers {
       .replaceAll("def_", "def _")
       .replaceAll("=_", " = _")
       .replaceAll(",_", ", _")
+      .replaceAll(",\\(", ", (")
       .replaceAll("if\\(", "if (")
       .replaceAll("=\\(", " = (")
       .replaceAll(":\\(", " : (")

sql/bridge/src/test/scala/app/softnetwork/elastic/sql/SQLQuerySpec.scala

@@ -2351,7 +2351,7 @@ class SQLQuerySpec extends AnyFlatSpec with Matchers {
         |    "substr": {
         |      "script": {
         |        "lang": "painless",
-        |        "source": "(def arg0 = (!doc.containsKey('identifier2') || doc['identifier2'].empty ? null : doc['identifier2'].value); (arg0 == null) ? null :  def _start = (1 - 1); def _end = _start + 3; (_start < 0 || _end > arg0.length()) ? null : arg0.substring(_start, _end)         )"
+        |        "source": "(def arg0 = (!doc.containsKey('identifier2') || doc['identifier2'].empty ? null : doc['identifier2'].value); (arg0 == null) ? null : ((1 - 1) < 0 || (1 - 1 + 3) > arg0.length()) ? null : arg0.substring((1 - 1), (1 - 1 + 3)))"
         |      }
         |    },
         |    "trim": {
@@ -2381,6 +2381,7 @@ class SQLQuerySpec extends AnyFlatSpec with Matchers {
         .replaceAll("def_", "def _")
         .replaceAll("=_", " = _")
         .replaceAll(",_", ", _")
+        .replaceAll(",\\(", ", (")
         .replaceAll("if\\(", "if (")
         .replaceAll("=\\(", " = (")
         .replaceAll(":\\(", " : (")

sql/src/main/scala/app/softnetwork/elastic/sql/SQLFunction.scala

@@ -1068,27 +1068,21 @@ case class SQLSubstring(str: PainlessScript, start: Int, length: Option[Int])
     callArgs match {
       // SUBSTRING(expr, start, length)
       case List(arg0, arg1, arg2) =>
-        s"""def _start = ($arg1 - 1);
-           |def _end = _start + $arg2;
-           |(_start < 0 || _end > $arg0.length()) ? null : $arg0.substring(_start, _end)""".stripMargin
-          .replaceAll("\n", " ")
+        s"(($arg1 - 1) < 0 || ($arg1 - 1 + $arg2) > $arg0.length()) ? null : $arg0.substring(($arg1 - 1), ($arg1 - 1 + $arg2))"
 
       // SUBSTRING(expr, start)
       case List(arg0, arg1) =>
-        s"""def _start = ($arg1 - 1);
-           |(_start < 0 || _start >= $arg0.length()) ? null : $arg0.substring(_start)""".stripMargin
-          .replaceAll("\n", " ")
+        s"(($arg1 - 1) < 0 || ($arg1 - 1) >= $arg0.length()) ? null : $arg0.substring(($arg1 - 1))"
 
       case _ => throw new IllegalArgumentException("SUBSTRING requires 2 or 3 arguments")
     }
   }
+
   override def validate(): Either[String, Unit] =
-    if (start < 0)
-      Left("SUBSTRING start position must be greater than or equal to 0")
+    if (start < 1)
+      Left("SUBSTRING start position must be greater than or equal to 1 (SQL is 1-based)")
     else if (length.exists(_ < 0))
       Left("SUBSTRING length must be non-negative")
-    else if (length.exists(_ < start))
-      Left("SUBSTRING length must be greater than or equal to start position")
     else Right(())
 
   override def toSQL(base: String): String = sql