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)
}

// Builder builder interface
type Builder interface {
	Writer
	WriteQuoted(field interface{})

package clause_test

import (
	"fmt"
	"sort"
	"strings"
	"testing"

	"gorm.io/gorm/clause"
)

func TestSet(t *testing.T) {
	results := []struct {
		Clauses []clause.Interface
		Result  string
		Vars    []interface{}
	}{
		{
			[]clause.Interface{
				clause.Update{},
				clause.Set([]clause.Assignment{{clause.PrimaryColumn, 1}}),
			},
			"UPDATE `users` SET `users`.`id`=?",
			[]interface{}{1},
		},

				"age": 18,
			},
			expect: clause.Values{
				Columns: []clause.Column{{Name: "age"}},
				Values:  [][]interface{}{{18}},
			},
		},
		{
			name: "Test convert float value",
			input: map[string]interface{}{
				"score": 99.5,
			},
			expect: clause.Values{
				Columns: []clause.Column{{Name: "score"}},
				Values:  [][]interface{}{{99.5}},
			},
		},
		{

		clauses := []clause.Interface{
			clause.Select{},
			clause.From{},
			clause.Where{Exprs: []clause.Expression{
				clause.Eq{Column: clause.PrimaryColumn, Value: "1"},
				clause.Gt{Column: "age", Value: 18},
				clause.Or(clause.Neq{Column: "name", Value: "jinzhu"}),
			}},
			clause.Where{Exprs: []clause.Expression{

		},
		{
			[]clause.Interface{clause.Select{
				Columns: []clause.Column{clause.PrimaryColumn},
			}, clause.Select{
				Columns: []clause.Column{{Name: "name"}},
			}, clause.From{}},
			"SELECT `name` FROM `users`", nil,
		},
		{
			[]clause.Interface{clause.Select{
				Expression: clause.CommaExpression{
					Exprs: []clause.Expression{
						clause.NamedExpr{"?", []interface{}{clause.Column{Name: "id"}}},

					if orCond, ok := expr.(clause.OrConditions); ok && len(orCond.Exprs) == 1 {
						where.Exprs = []clause.Expression{clause.And(where.Exprs...)}
						c.Expression = where
						stmt.Clauses["WHERE"] = c
						break
					}
				}
			}
		}

		stmt.AddClause(clause.Where{Exprs: []clause.Expression{
			clause.Eq{Column: clause.Column{Table: clause.CurrentTable, Name: sd.Field.DBName}, Value: sd.ZeroValue},
		}})

func (limit Limit) MergeClause(clause *Clause) {
	clause.Name = ""

	if v, ok := clause.Expression.(Limit); ok {
		if (limit.Limit == nil || *limit.Limit == 0) && v.Limit != nil {
			limit.Limit = v.Limit
		}

		if limit.Offset == 0 && v.Offset > 0 {
			limit.Offset = v.Offset
		} else if limit.Offset < 0 {
			limit.Offset = 0
		}
	}

	clause.Expression = limit

	}
}

// MergeClause merge order by clauses
func (returning Returning) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Returning); ok {
		returning.Columns = append(v.Columns, returning.Columns...)
	}

	clause.Expression = returning

package clause_test

import (
	"fmt"
	"testing"

	"gorm.io/gorm/clause"
)

func TestValues(t *testing.T) {
	results := []struct {
		Clauses []clause.Interface
		Result  string
		Vars    []interface{}
	}{
		{
			[]clause.Interface{
				clause.Insert{},
				clause.Values{
					Columns: []clause.Column{{Name: "name"}, {Name: "age"}},
					Values:  [][]interface{}{{"jinzhu", 18}, {"josh", 1}},
				},
			},

		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Limit: &limit0}},
			"SELECT * FROM `users` LIMIT ?",
			[]interface{}{limit0},
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Limit: &limit0}, clause.Limit{Offset: 0}},
			"SELECT * FROM `users` LIMIT ?",
			[]interface{}{limit0},
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Offset: 20}},