/SmarterSql/SmarterSql/Parsing/Keywords/KeywordCTE.cs

// ---------------------------------

// SmarterSql (c) Johan Sassner 2008

// ---------------------------------

using System;

using System.Collections.Generic;

using Sassner.SmarterSql.ParsingUtils;

using Sassner.SmarterSql.Tree;

using Sassner.SmarterSql.Utils;



namespace Sassner.SmarterSql.Parsing.Keywords {

	public class KeywordCTE {

		#region Member variables



		private const string ClassName = "KeywordCTE";



		#endregion



		#region Parse CTE's



		/// <summary>

		/// Parse a CTE for its content

		/// </summary>

		/// <param name="parser"></param>

		/// <param name="lstTokens"></param>

		/// <param name="i"></param>

		public static void ParseCTE(Parser parser, List<TokenInfo> lstTokens, ref int i) {

			try {

				TokenInfo token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

				if (null != token) {

					i++;

					token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

					if (null != token && token.Type == TokenType.Identifier) {

						string Table = token.Token.UnqoutedImage;

						token.TokenContextType = TokenContextType.CTEName;

						i++;

						token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

						List<string> lstColumNames = new List<string>();



						// If parenthesis, store named columns

						if (null != token && token.Kind == TokenKind.LeftParenthesis) {

							int matchingBracesIndex = token.MatchingParenToken;

							if (-1 != matchingBracesIndex && i < matchingBracesIndex) {

								i++;

								while (i < matchingBracesIndex) {

									token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

									if (null != token) {

										if (token.Type == TokenType.Identifier) {

											lstColumNames.Add(token.Token.UnqoutedImage);

											token.TokenContextType = TokenContextType.NewColumnAlias;

										}

									} else {

										return;

									}

									i++;

								}

								i++;

							} else {

								return;

							}

						}



						// Find the SELECT span and store it for later parsing

						token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

						if (null != token && token.Kind == TokenKind.KeywordAs) {

							i++;

							token = InStatement.GetNextNonCommentToken(lstTokens, ref i);

							if (null != token && token.Kind == TokenKind.LeftParenthesis) {

								int matchingBracesIndex = token.MatchingParenToken;

								if (-1 != matchingBracesIndex && i < matchingBracesIndex) {

									int startIndex = InStatement.GetNextNonCommentToken(lstTokens, i + 1, i + 1);

									int endIndex = matchingBracesIndex - 1;

									token = InStatement.GetNextNonCommentToken(lstTokens, startIndex);



									StatementSpans ss;

									Common.GetStatementSpan(token.Span, parser.SegmentUtils.StartTokenIndexes, token.ParenLevel, out ss);

									int selectStartIndex;

									int selectEndIndex;

									if (null != ss) {

										selectStartIndex = (-1 == ss.FromIndex ? ss.StartIndex : InStatement.GetNextNonCommentToken(lstTokens, ss.FromIndex + 1, ss.FromIndex + 1));

										selectEndIndex = ss.EndIndex;

									} else {

										selectStartIndex = startIndex;

										selectEndIndex = endIndex;

									}



									ScannedTable newScannedTable = new ScannedTable("", "", "", Table, Table, token.Span, token.ParenLevel, startIndex, endIndex, selectStartIndex, selectEndIndex, Common.enSqlTypes.CTE, lstColumNames);

									parser.ScannedTables.Add(newScannedTable);

								}

							}

						}

					}

				}

			} catch (Exception e) {

				Common.LogEntry(ClassName, "ParseCTE", e, Common.enErrorLvl.Error);

			}

		}



		#endregion

	}

}