// Package clause provides the clause interface and common clause implementations for GORM.
package clause

// Interface clause interface
type Interface interface {
	Name() string
	Build(Builder)
	MergeClause(*Clause)
}

// ClauseBuilder clause builder, allows to customize how to build clause
type ClauseBuilder func(Clause, Builder)

type Writer interface {
	WriteByte(byte) error
	WriteString(string) (int, error)
}

SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

	}
}

// MergeClause merge order by clauses
func (returning Returning) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Returning); ok && len(returning.Columns) > 0 {
		if v.Columns != nil {
			returning.Columns = append(v.Columns, returning.Columns...)
		} else {
			returning.Columns = nil
		}
	}
	clause.Expression = returning

		} else {
			expr.Build(builder)
		}
	}
}

// MergeClause merge where clauses
func (where Where) MergeClause(clause *Clause) {
	if w, ok := clause.Expression.(Where); ok {
		exprs := make([]Expression, len(w.Exprs)+len(where.Exprs))
		copy(exprs, w.Exprs)
		copy(exprs[len(w.Exprs):], where.Exprs)
		where.Exprs = exprs
	}

	clause.Expression = where
}

func And(exprs ...Expression) Expression {

	tx = tx.Where("age = ?", 20)
	c, ok := tx.Statement.Clauses["WHERE"]
	if !ok {
		t.Fatalf("WHERE clause expected")
	}
	if where, ok := c.Expression.(clause.Where); !ok || len(where.Exprs) == 0 {
		t.Fatalf("WHERE expressions expected, got %v", c.Expression)
	}

	// Order
	tx = tx.Order("name DESC")
	if _, ok := tx.Statement.Clauses["ORDER BY"]; !ok {
		t.Fatalf("ORDER BY clause expected")
	}

	// Limit / Offset

#*    *##elseif ( $license.name == "BSD-2-Clause" || $license.name == "The BSD 2-Clause License"
                    || $license.url.contains( "www.opensource.org/licenses/bsd-license" ) )
#*      *##set ( $spdx = 'BSD-2-Clause' )
#*    *##elseif ( $license.name == "BSD-3-Clause"
                    || $license.url.contains( "opensource.org/licenses/BSD-3-Clause" ) )
#*      *##set ( $spdx = 'BSD-3-Clause' )

		return stmt, err
	}

	// Analyze where clause
	if selectAST.Where != nil {
		whereQProp := selectAST.Where.analyze(&selectAST)
		if whereQProp.err != nil {
			err = errQueryAnalysisFailure(fmt.Errorf("Where clause error: %w", whereQProp.err))
			return stmt, err
		}

		if whereQProp.isAggregation {
			err = errQueryAnalysisFailure(errors.New("WHERE clause cannot have an aggregation"))
			return stmt, err
		}
	}

		builder.WriteByte('=')
		builder.WriteQuoted(Column{Name: PrimaryKey})
	}
}

// MergeClause merge assignments clauses
func (set Set) MergeClause(clause *Clause) {
	copiedAssignments := make([]Assignment, len(set))
	copy(copiedAssignments, set)
	clause.Expression = Set(copiedAssignments)
}

// Assignments implements Assigner for Set.
func (set Set) Assignments() []Assignment { return []Assignment(set) }

//	}})
func (db *DB) Order(value interface{}) (tx *DB) {
	tx = db.getInstance()

	switch v := value.(type) {
	case clause.OrderBy:
		tx.Statement.AddClause(v)
	case clause.OrderByColumn:
		tx.Statement.AddClause(clause.OrderBy{
			Columns: []clause.OrderByColumn{v},
		})
	case string:
		if v != "" {
			tx.Statement.AddClause(clause.OrderBy{
				Columns: []clause.OrderByColumn{{