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

// SmarterSql (c) Johan Sassner 2008

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

using System.Collections.Generic;

using Sassner.SmarterSql.Objects;

using Sassner.SmarterSql.ParsingObjects;

using Sassner.SmarterSql.ParsingUtils;

using Sassner.SmarterSql.Tree;

using Sassner.SmarterSql.Utils;



namespace Sassner.SmarterSql.Parsing.Keywords {

	public class KeywordTrigger {



		#region HandleEnableDisableTrigger



		// ENABLE TRIGGER { [ schema_name . ] trigger_name [ ,...n ] | ALL }

		// ON { object_name | DATABASE | ALL SERVER } [ ; ]

		//

		// DISABLE TRIGGER { [ schema . ] trigger_name [ ,...n ] | ALL }

		// ON { object_name | DATABASE | ALL SERVER } [ ; ]

		public static void HandleEnableDisableTrigger(List<TokenInfo> lstTokens, ref int i) {

			i++;

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

			if (null == nextToken) {

				return;

			}



			if (nextToken.Kind == TokenKind.KeywordAll) {

				// Ok

			} else if (nextToken.Type == TokenType.Identifier) {

				// [ schema_name . ] trigger_name [ ,...n ]

				int offset = i - 1;

				while (true) {

					offset++;

					nextToken = InStatement.GetNextNonCommentToken(lstTokens, ref offset);

					offset++;

					TokenInfo nextNextToken = InStatement.GetNextNonCommentToken(lstTokens, ref offset);



					if (null != nextNextToken && nextNextToken.Kind == TokenKind.Dot) {

						offset++;

						nextNextToken = InStatement.GetNextNonCommentToken(lstTokens, ref offset);

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

							nextToken.TokenContextType = TokenContextType.SysObjectSchema;

							nextNextToken.TokenContextType = TokenContextType.Trigger;

							i = offset;

						} else {

							return;

						}

					} else {

						nextToken.TokenContextType = TokenContextType.Trigger;

					}



					offset++;

					nextToken = InStatement.GetNextNonCommentToken(lstTokens, ref offset);

					if (null == nextToken || nextToken.Kind != TokenKind.Comma) {

						break;

					}

					i = offset;

				}

			} else {

				return;

			}



			// ON

			if (!InStatement.GetIfAllNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordOn)) {

				return;

			}



			// { object_name | DATABASE | ALL SERVER }

			Parser parser = TextEditor.CurrentWindowData.Parser;



			if (InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordAll, TokenKind.KeywordDatabase)) {

				if (nextToken.Kind == TokenKind.KeywordAll && !InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordServer)) {

					return;

				}

			} else if (null != nextToken && nextToken.Type == TokenType.Identifier) {

				// Normal multi part name

				TokenInfo server_name;

				TokenInfo database_name;

				TokenInfo schema_name;

				TokenInfo object_name;

				int endTableIndex;

				if (!parser.ParseTableOrViewName(i, out endTableIndex, out server_name, out database_name, out schema_name, out object_name)) {

					return;

				}

			}

		}



		#endregion



		#region Parse CREATE/ALTER TRIGGER



		// --- Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) ---------

		//CREATE TRIGGER [ schema_name . ]trigger_name 

		// ON { table | view } 

		//[ WITH <dml_trigger_option> [ ,...n ] ]

		//{ FOR | AFTER | INSTEAD OF } 

		//{ [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] } 

		//[ WITH APPEND ] 

		//[ NOT FOR REPLICATION ] 

		//AS { sql_statement  [ ; ] [ ...n ] | EXTERNAL NAME <method specifier [ ; ] > }

		//

		// ---- Trigger on a CREATE, ALTER, DROP, GRANT, DENY, REVOKE, or UPDATE STATISTICS statement (DDL Trigger) --------

		//CREATE TRIGGER trigger_name 

		//ON { ALL SERVER | DATABASE } 

		//[ WITH <ddl_trigger_option> [ ,...n ] ]

		//{ FOR | AFTER } { event_type | event_group } [ ,...n ]

		//AS { sql_statement  [ ; ] [ ...n ] | EXTERNAL NAME < method specifier >  [ ; ] }

		//

		//<dml_trigger_option> ::=

		//    [ ENCRYPTION ]

		//    [ EXECUTE AS Clause ]

		//

		public static void HandleCreateAlterTrigger(StatementSpans currentStartSpan, List<TokenInfo> lstTokens, ref int i, ref int sysObjectId, List<SysObject> lstSysObjects) {

			Parser parser = TextEditor.CurrentWindowData.Parser;

			i++;

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

			if (null == nextToken || nextToken.Type != TokenType.Identifier) {

				return;

			}

			int index = i + 1;

			TokenInfo nextNextToken = InStatement.GetNextNonCommentToken(lstTokens, ref index);

			if (null != nextNextToken && nextNextToken.Kind == TokenKind.Dot) {

				index++;

				nextNextToken = InStatement.GetNextNonCommentToken(lstTokens, ref index);

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

					nextToken.TokenContextType = TokenContextType.SysObjectSchema;

					nextNextToken.TokenContextType = TokenContextType.Trigger;

					i = index;

				} else {

					return;

				}

			} else {

				nextToken.TokenContextType = TokenContextType.Trigger;

			}



			if (!InStatement.GetIfAllNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordOn)) {

				return;

			}



			// DDL Trigger

			if (InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordAll, TokenKind.KeywordDatabase)) {

				#region DDL Trigger



				bool serverScope = (nextToken.Kind == TokenKind.KeywordAll);

				if (nextToken.Kind == TokenKind.KeywordAll && !InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordServer)) {

					return;

				}



				if (!ParseDmlTrigger(ref i, lstTokens)) {

					return;

				}



				// { FOR | AFTER } 

				if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordFor, TokenKind.KeywordAfter)) {

					return;

				}



				// { event_type | event_group } [ ,...n ]

				int offset = i;

				while (true) {

					offset++;

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

					Token foundToken;

					if (serverScope) {

						if (!Instance.StaticData.DdlStatementsServerScope.TryGetValue(token.Token, out foundToken)) {

							token.TokenContextType = TokenContextType.Unknown;

							return;

						}

					} else {

						if (!Instance.StaticData.DdlStatementsDatabaseScope.TryGetValue(token.Token, out foundToken)) {

							token.TokenContextType = TokenContextType.Unknown;

							return;

						}

					}



					if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.Comma)) {

						break;

					}

				}

				i = offset;



				// AS



				#endregion



			} else {

				#region DML Trigger



				int startTableIndex = i + 1;



				TokenInfo server_name;

				TokenInfo database_name;

				TokenInfo schema_name;

				TokenInfo object_name;

				int endTableIndex;

				if (!parser.ParseTableOrViewName(startTableIndex, out endTableIndex, out server_name, out database_name, out schema_name, out object_name)) {

					return;

				}

				i = endTableIndex;



				// Normal multi part name

				if (!ParseDmlTrigger(ref i, lstTokens)) {

					return;

				}



				// { FOR | AFTER | INSTEAD OF } 

				if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordFor, TokenKind.KeywordAfter, TokenKind.KeywordInstead)) {

					return;

				}

				if (nextToken.Kind == TokenKind.KeywordInstead && !InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordOf)) {

					return;

				}



				// { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] }

				while (true) {

					if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordInsert, TokenKind.KeywordUpdate, TokenKind.KeywordDelete)) {

						return;

					}

					if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.Comma)) {

						break;

					}

				}



				// [ WITH APPEND ]

				InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordWith, TokenKind.KeywordAppend);



				// [ NOT FOR REPLICATION ] 

				InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordNot, TokenKind.KeywordFor, TokenKind.KeywordReplication);



				// AS



				// Create insert / delete logical (conceptual) tables



				SysObject foundSysObject;

				if (!Instance.TextEditor.ActiveConnection.SysObjectExists(schema_name, object_name, out foundSysObject)) {

					return;

				}



				CreateLogicalTable(lstTokens, parser, schema_name, "inserted", string.Empty, ref sysObjectId, lstSysObjects, foundSysObject, startTableIndex, endTableIndex, currentStartSpan);

				CreateLogicalTable(lstTokens, parser, schema_name, "deleted", string.Empty, ref sysObjectId, lstSysObjects, foundSysObject, startTableIndex, endTableIndex, currentStartSpan);



				#endregion

			}

		}



		private static void CreateLogicalTable(List<TokenInfo> lstTokens, Parser parser, TokenInfo schema_name, string Table, string Alias, ref int sysObjectId, List<SysObject> lstSysObjects, SysObject foundSysObject, int startTableIndex, int endTableIndex, StatementSpans currentStartSpan) {

			const Common.enSqlTypes sqlType = Common.enSqlTypes.Temporary;

			SysObject addedSysObject = SysObject.CreateTemporarySysObject(Table, sqlType, ref sysObjectId);

			lstSysObjects.Add(addedSysObject);

			foreach (SysObjectColumn column in foundSysObject.Columns) {

				addedSysObject.AddColumn(new SysObjectColumn(addedSysObject, column.ColumnName, column.ParsedDataType, column.IsNullable, column.IsIdentity));

			}

			// Create the table source

			StatementSpans ss = parser.SegmentUtils.GetStatementSpan(startTableIndex);

			Table table = new Table(string.Empty, string.Empty, (null != schema_name ? schema_name.Token.UnqoutedImage : string.Empty), Table, Alias, addedSysObject, ss, startTableIndex, endTableIndex, true);

			TableSource addedTableSource = new TableSource(lstTokens[startTableIndex].Token, table, startTableIndex, endTableIndex);

			parser.TableSources.Add(addedTableSource);

			if (null != currentStartSpan) {

				currentStartSpan.AddTableSource(addedTableSource);

			}

		}



		#endregion



		#region ParseDmlTrigger



		// [ WITH <dml_trigger_option> [ ,...n ] ]

		//   <dml_trigger_option> ::=

		//      [ ENCRYPTION ]

		//      [ EXECUTE AS Clause ]

		private static bool ParseDmlTrigger(ref int i, List<TokenInfo> lstTokens) {

			TokenInfo nextToken;

			if (InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordWith)) {

				while (true) {

					if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordEncryption, TokenKind.KeywordExec)) {

						return false;

					}

					if (nextToken.Kind == TokenKind.KeywordExec) {

						if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordAs)) {

							return false;

						}

						if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.KeywordCaller, TokenKind.KeywordSelf, TokenKind.KeywordOwner, TokenKind.ValueString)) {

							return false;

						}

					}



					if (!InStatement.GetIfAnyNextValidToken(lstTokens, ref i, out nextToken, TokenKind.Comma)) {

						if (null == nextToken) {

							return false;

						}

						break;

					}

				}

			}

			return true;

		}



		#endregion

	}

}