/*
# PostgreSQL Database Modeler (pgModeler)
#
# Copyright 2006-2020 - Raphael Araújo e Silva <raphael@pgmodeler.io>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation version 3.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# The complete text of GPLv3 is at LICENSE file on source code root directory.
# Also, you can get the complete GNU General Public License at <http://www.gnu.org/licenses/>
*/

/**
\ingroup libpgmodeler
\class Trigger
\brief Implements the operations to manipulate triggers on the database.
\note <strong>Creation date:</strong> 11/10/2006
*/

#ifndef TRIGGER_H
#define TRIGGER_H

#include "tableobject.h"
#include "function.h"
#include "pgsqltypes/firingtype.h"
#include "pgsqltypes/eventtype.h"
#include "pgsqltypes/deferraltype.h"

class Trigger: public TableObject{
	private:
		//! \brief Stores the transtion tables names (OLD and NEW) [REFERENCING { OLD | NEW } TABLE name]
		QString transition_tabs_names[2];

		//! \brief Arguments passed to the function that trigger executes
		QStringList arguments;

		/*! \brief Column list used as the trigger firing condition. This attribute was
		 introduced in PostgreSQL 9.1 and it is used only when the UPDATE event
		 is assigned to trigger. */
		vector<Column *> upd_columns;

		//! \brief Function that is excuted when the trigger is activated
		Function *function;

		//! \brief Condition that guarantees the trigger's execution
		QString condition;

		//! \brief Trigger firing mode (BEFORE, AFTER, INSTEAD OF)
		FiringType firing_type;

		//! \brief Map that marks which events activates the trigger
		map<EventType, bool> events;

		//! \brief Flag that indicates whether the function must be executed by row
		bool is_exec_per_row;

		//! \brief Table referecend by the trigger (only for constraint trigger)
		BaseTable *referenced_table;

		//! \brief Indicates if the trigger is a constraint trigger
		bool is_constraint,

		//! \brief Indicates whether the trigger is deferrable (only for constraint trigger)
		is_deferrable;

		//! \brief Deferral type for the trigger (only for constraint trigger)
		DeferralType deferral_type;

		//! \brief Formats the basic trigger attributes to be used by SchemaParser
		void setBasicAttributes(unsigned def_type);

		//! \brief Format the function arguments to be used by the SchemaParser
		void setArgumentAttribute(unsigned tipo_def);

	public:
		static constexpr unsigned OldTableName=0, NewTableName=1;

		Trigger();

		/*! \brief Adds a column as a firing condition (only when the event UPDATE is used).
		 The columns added by this method must belongs to the trigger owner table. */
		void addColumn(Column *column);

		//! \brief Adds an argument to the trigger
		void addArgument(const QString &arg);

		//! \brief Adds a list of arguments to the trigger
		void addArguments(const QStringList &args);

		//! \brief Defines in which events the trigger is executed
		void setEvent(EventType event, bool value);

		//! \brief Defines the function to be executed by the trigger
		void setFunction(Function *func);

		//! \brief Defines the firing condition for trigger
		void setCondition(const QString &cond);

		//! \brief Defines the referenced table (only for constraint trigger)
		void setReferecendTable(BaseTable *ref_table);

		//! \brief Defines the deferral type
		void setDeferralType(DeferralType type);

		//! \brief Defines whether the trigger is deferrable or not
		void setDeferrable(bool value);

		//! \brief Changes the specified trigger agument replacing the current argument by the 'new_arg'
		void editArgument(unsigned arg_idx, const QString &new_arg);

		//! \brief Defines the moment when the trigger must be executed
		void setFiringType(FiringType firing_type);

		//! \brief Defines wheter the trigger executes per row
		void setExecutePerRow(bool value);

		//! \brief Defines if the trigger is constraint
		void setConstraint(bool value);

		//! \brief Defines the transition table name (OLD|NEW) referenced by the trigger
		void setTransitionTableName(unsigned tab_idx, const QString &name);

		//! \brief Returns the transition table name (OLD|NEW) referenced by the trigger
		QString getTransitionTableName(unsigned tab_idx);

		//! \brief Returns true if the trigger executes on the passed event
		bool isExecuteOnEvent(EventType event);

		//! \brief Returns the current EXECUTE PER ROW state
		bool isExecutePerRow();

		//! \brief Gets one reference column by its index
		Column *getColumn(unsigned col_idx);

		//! \brief Gets one argument by its index
		QString getArgument(unsigned arg_idx);

		//! \brief Gets the trigger firing condition
		QString getCondition();

		//! \brief Returns the function executed by the trigger
		Function *getFunction();

		//! \brief Returns the trigger argument count
		unsigned getArgumentCount();

		//! \brief Returns the reference column count
		unsigned getColumnCount();

		//! \brief Returns when the trigger executes
		FiringType getFiringType();

		//! \brief Remove an argument using its index
		void removeArgument(unsigned arg_idx);

		//! \brief Remove all arguments
		void removeArguments();

		//! \brief Remove all referenced columns
		void removeColumns();

		//! \brief Returns the referenced table
		BaseTable *getReferencedTable();

		//! \brief Returns the deferral type of the constraint trigger
		DeferralType getDeferralType();

		//! \brief Returns if the constraint trigger is deferrable or not
		bool isDeferrable();

		//! \brief Returns if the trigger is configured as a constraint trigger
		bool isConstraint();

		/*! \brief Returns whether the trigger references columns added
		 by relationship. This method is used as auxiliary
		 to control which triggers reference columns added by the
		 relationship in order to avoid referece breaking due constants
		 connections and disconnections of relationships */
		bool isReferRelationshipAddedColumn();

		/*! \brief Returns the list of all columns that is created by relationships.
	This method is slower than isReferRelationshipAddedColumn() so it's not
	recommended to use it only check if the object is referencing columns
	added by relationship */
		vector<Column *> getRelationshipAddedColumns();

		//! \brief Returns the SQL / XML definition for the trigger
		virtual QString getCodeDefinition(unsigned def_type) final;

		/*! \brief Validates the trigger attributes according to the docs.
		This method is executed whenever the trigger is added to a table or view.
		Normally the user don't need to call it explicitly */
		void validateTrigger();

		virtual QString getSignature(bool format=true) final;
};

#endif
