// Trace FiveSql2 execution step by step
#include "FiveSqlDef.ch"
#include "hbclass.ch"

FUNCTION Main()
   LOCAL oLexer, oParser, aTokens, hQuery
   LOCAL cSQL

   // Create test table
   dbCreate("trace_test", { {"ID","N",4,0}, {"NAME","C",20,0} })
   USE "trace_test" NEW EXCLUSIVE
   APPEND BLANK
   REPLACE ID WITH 1, NAME WITH "Alice"
   APPEND BLANK
   REPLACE ID WITH 2, NAME WITH "Bob"
   CLOSE ALL

   cSQL := "SELECT * FROM trace_test"

   ? "=== Step 1: Lexer ==="
   oLexer := TSqlLexer():New( cSQL )
   oLexer:Tokenize()
   aTokens := oLexer:GetTokens()
   ? "Tokens:", Len(aTokens)
   LOCAL i
   FOR i := 1 TO Len(aTokens)
      ?? " [" + LTrim(Str(aTokens[i][1])) + ":" + aTokens[i][2] + "]"
   NEXT
   ?

   ? "=== Step 2: Parser ==="
   oParser := TSqlParser2():New( aTokens, {} )
   hQuery := oParser:Parse()
   ? "hQuery type:", ValType(hQuery)
   IF ValType(hQuery) == "H"
      ? "Keys:"
      LOCAL aKeys
      aKeys := hb_HKeys(hQuery)
      FOR i := 1 TO Len(aKeys)
         ? "  ", aKeys[i], "=", ValType(hQuery[aKeys[i]])
         IF ValType(hQuery[aKeys[i]]) == "A"
            ? "    len:", Len(hQuery[aKeys[i]])
         ELSEIF ValType(hQuery[aKeys[i]]) == "C"
            ? "    val:", hQuery[aKeys[i]]
         ENDIF
      NEXT
   ENDIF

   ? "=== Step 3: Check tables ==="
   IF hb_HHasKey(hQuery, "tables")
      LOCAL aTables
      aTables := hQuery["tables"]
      ? "Tables:", Len(aTables)
      FOR i := 1 TO Len(aTables)
         ? "  Table", i, ":", ValType(aTables[i])
         IF ValType(aTables[i]) == "A"
            ? "    len:", Len(aTables[i])
            LOCAL j
            FOR j := 1 TO Len(aTables[i])
               ? "    [" + LTrim(Str(j)) + "]:", ValType(aTables[i][j]), aTables[i][j]
            NEXT
         ENDIF
      NEXT
   ENDIF

   FErase("trace_test.dbf")
   ? "=== DONE ==="
RETURN NIL