package gudusoft.gsqlparser.nodes;

import gudusoft.gsqlparser.*;

/**
 * @deprecated As of v2.7.4.0, Please use  {@link TJoinExpr} instead.
 *
 * A list of join {@link TCustomSqlStatement#joins} represents table sources in following clauses of SQL statement:
 * <ul>
 * <li>from clause of select statement.</li>
 * <li>from clause of delete statement, Specifies an additional FROM clause, This Transact-SQL extension to DELETE allows specifying data from table_source and deleting the corresponding rows from the table in the first FROM clause.</li>
 * <li>from clause of update statement, Specifies that a table, view, or derived table source is used to provide the criteria for the update operation. </li>
 * </ul>
 * <br>Each table source in from clause was treated as a join which is type of {@link TJoin}.
 * <br>The reason for this design is that we can treat all table sources in from clause in a uniform way.
 * <br>
 */

public class TJoin extends TNodeWithAliasClause {
    private int kind;
    private TJoin join;
    private TTable table;
    private TJoinItemList joinItems = null;
    private boolean withParen = false;

    private int nestedParen = 0;

    public void setNestedParen(int nestedParen) {
        if (nestedParen > 0) withParen = true;
        this.nestedParen = nestedParen;
    }

    public int getNestedParen() {
        return nestedParen;
    }

    public void setWithParen(boolean withParen) {
        this.withParen = withParen;
    }

    public boolean isWithParen() {

        return withParen;
    }

    public void setJoinItems(TJoinItemList joinItems) {
        this.joinItems = joinItems;
    }

    public void setJoin(TJoin join) {
        this.join = join;
    }

    public void setTable(TTable table) {
        this.table = table;
//        if (table == null) return;
//        if (this.table.getTableType() == ETableSource.subquery){
//            this.table.getSubquery().setLocation(ESqlClause.join);
//        }
    }

    public void setKind(int kind) {
        this.kind = kind;
    }

    /**
     * List of joinItems.
     * <p>SQL 1:
     *<blockquote>select f from t1 left join t2 on t1.f1 = t2.f1 right join t3 on t1.f1 = t3.f1</blockquote>
     * Text in Item 0 will be: left join t2 on t1.f1 = t2.f1
     * <p>Text in Item 1 will be: right join t3 on t1.f1 = t3.f1
     * <p>Check {@link TJoinItem} to see how information was organized.
     * @return
     */
    public TJoinItemList getJoinItems() {
        if (joinItems == null){
            joinItems = new TJoinItemList();
        }
        return joinItems;
    }

    /**
     *
     * @return this join start with another join( (a as a_alias left join a1 on a1.f1 = a_alias.f1) as a_join ) in SQL:
     * <blockquote>
     * select a_join.f1
     * from (a as a_alias left join a1 on a1.f1 = a_alias.f1) as a_join
     * join b on a_join.f1 = b.f1;
     * </blockquote>
     */
    public TJoin getJoin() {
        return join;
    }

    /**
     *
     * @return this join start with a table(t1) in SQL:
     * <blockquote>select f from t1 join t2 on t1.f1 = t2.f1</blockquote>
     */
    public TTable getTable() {
        return table;
    }

    /**
     * According to the table source in from clause, there are 3 kinds of join.
     * <ul>
     * <li>{@link TBaseType#join_source_fake}, it's a fake join like <blockquote>select f from t1</blockquote>
     * the whole from clause was represented by this class, you can get text representation of this from clause by using toString() method, it returns "t1" .
     * and table t1 can be fetch from {@link #getTable}.</li>
     * <li>{@link TBaseType#join_source_table},<blockquote>select f from t1 join t2 on t1.f1 = t2.f1</blockquote>
     * the whole from clause was represented by this class, you can get text representation of this from clause by using toString() method,
     * it returns "t1 join t2 on t1.f1 = t2.f1".
     * t1 can be fetch from {@link #getTable}.</li>
     * <li>{@link TBaseType#join_source_join},
     * <blockquote>
     * select a_join.f1
     * from (a as a_alias left join a1 on a1.f1 = a_alias.f1) as a_join
     * join b on a_join.f1 = b.f1;
     * </blockquote>
     * the whole from clause was represented by this class, you can get text representation of this from clause by using toString() method,
     * it returns "(a as a_alias left join a1 on a1.f1 = a_alias.f1) as a_join join b on a_join.f1 = b.f1".
     * <p>(a as a_alias left join a1 on a1.f1 = a_alias.f1) can be fetched from {@link #getJoin}.
     * </li>
     * </ul>
     * @return
     */
    public int getKind() {
        return kind;
    }

    public TJoin(){
       this.kind = TBaseType.join_source_fake;
    }


    /**
     *
     * @return alias of {@link #getJoin}, valid only when {@link #getKind = TBaseType#join_source_join}.
     * In this SQL, alias is "as a_join"
     * <blockquote>
     * select a_join.f1
     * from (a as a_alias left join a1 on a1.f1 = a_alias.f1) as a_join
     * join b on a_join.f1 = b.f1;
     * </blockquote>
     * <p>But in this SQL, alias is null, "as t1" is the alias of t1.
     * <blockquote><pre>
     * select f from t as t1 join t2 on t1.f1 = t2.f1</pre>
     * </blockquote>
     */
    public TAliasClause getAliasClause() {

        return super.getAliasClause();
    }

    public void accept(TParseTreeVisitor v){
        v.preVisit(this);

        v.postVisit(this);
    }

    public void acceptChildren(TParseTreeVisitor v){
        v.preVisit(this);



        switch (getKind()){
            case TBaseType.join_source_fake:
                getTable().acceptChildren(v);
                break;
            case TBaseType.join_source_table:
            case TBaseType.join_source_join:

                if (getKind() == TBaseType.join_source_table){
                    getTable().acceptChildren(v);
                }else if ( getKind() == TBaseType.join_source_join){
                    getJoin().acceptChildren(v);
                }

                this.getJoinItems().acceptChildren(v);


                break;
        }


        if (getAliasClause() != null){
            getAliasClause().acceptChildren(v);
        }

        v.postVisit(this);
    }


}