{{ define "dialect/sql/create" }}
{{ $builder := pascal $.Scope.Builder }}
{{ $receiver := receiver $builder }}

func ({{ $receiver }} *{{ $builder }}) sqlSave(ctx context.Context) (*{{ $.Name }}, error) {
	var (
		res sql.Result
		{{ $.Receiver }} = &{{ $.Name }}{config: {{ $receiver }}.config}
	)
	tx, err := {{ $receiver }}.driver.Tx(ctx)
	if err != nil {
		return nil, err
	}
	builder := sql.Insert({{ $.Package }}.Table).Default({{ $receiver }}.driver.Dialect())
	{{- range $_, $f := $.Fields }}
		if {{ $receiver }}.{{- $f.StructField }} != nil {
			builder.Set({{ $.Package }}.{{ $f.Constant }}, *{{ $receiver }}.{{ $f.StructField }})
			{{ $.Receiver }}.{{ pascal $f.Name }} = {{ if not $f.Nillable }}*{{ end }}{{ $receiver }}.{{ $f.StructField }}
		}
	{{- end }}
	query, args := builder.Query()
	if err := tx.Exec(ctx, query, args, &res); err != nil {
		return nil, rollback(tx, err)
	}
	id, err := res.LastInsertId()
	if err != nil {
		return nil, rollback(tx, err)
	}
	{{ $.Receiver }}.ID = {{ if $.ID.IsString }}strconv.FormatInt(id, 10){{ else }}int(id){{ end }}
	{{- range $_, $e := $.Edges }}
		if len({{ $receiver }}.{{ $e.StructField }}) > 0 {
			{{- if and $e.Unique $e.SelfRef }}{{/* O2O with self reference */}}
				for eid := range {{ $receiver }}.{{ $e.StructField }} {
					{{- template "dialect/sql/create/convertid" $e -}}
					query, args := sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
							Set({{ $.Package }}.{{ $e.ColumnConstant }}, eid).
							Where(sql.EQ({{ $.Package }}.{{ $.ID.Constant }}, id)).Query()
					if err := tx.Exec(ctx, query, args, &res); err != nil {
						return nil, rollback(tx, err)
					}
					query, args = sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
							Set({{ $.Package }}.{{ $e.ColumnConstant }}, id).
							Where(sql.EQ({{ $e.Type.Package }}.{{ $e.Type.ID.Constant }}, eid).And().IsNull({{ $.Package }}.{{ $e.ColumnConstant }})).Query()
					if err := tx.Exec(ctx, query, args, &res); err != nil {
						return nil, rollback(tx, err)
					}
					affected, err := res.RowsAffected()
					if err != nil {
						return nil, rollback(tx, err)
					}
					if int(affected) < len({{ $receiver }}.{{ $e.StructField }}) {
						return nil, rollback(tx, &ErrConstraintFailed{msg: fmt.Sprintf("\"{{ $e.Name }}\" (%v) already connected to a different \"{{ $.Name }}\"", eid)})
					}
				}
			{{- else if $e.M2M  }}
				for eid := range {{ $receiver }}.{{ $e.StructField }} {
					{{- template "dialect/sql/create/convertid" $e -}}
					{{ $a := 0 }}{{ $b := 1 }}{{- if $e.IsInverse }}{{ $a = 1 }}{{ $b = 0 }}{{ end }}
					query, args := sql.Insert({{ $.Package }}.{{ $e.TableConstant }}).
							Columns({{ $.Package }}.{{ $e.PKConstant }}[{{ $a }}], {{ $.Package }}.{{ $e.PKConstant }}[{{ $b }}]).
							Values(id, eid).
							{{- if $e.SelfRef }}{{/* self-ref creates the edges in both ways. */}}
								Values(eid, id).
							{{- end }}
							Query()
					if err := tx.Exec(ctx, query, args, &res); err != nil {
						return nil, rollback(tx, err)
					}
				}
			{{- else if $e.M2O }}
				for eid := range {{ $receiver }}.{{ $e.StructField }} {
					{{- template "dialect/sql/create/convertid" $e -}}
					query, args := sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
						Set({{ $.Package }}.{{ $e.ColumnConstant }}, eid).
						Where(sql.EQ({{ $.Package }}.{{ $.ID.Constant }}, id)).
						Query()
					if err := tx.Exec(ctx, query, args, &res); err != nil {
						return nil, rollback(tx, err)
					}
				}
			{{- else if $e.O2M }}
				p := sql.P()
				for eid := range {{ $receiver }}.{{ $e.StructField }} {
					{{- template "dialect/sql/create/convertid" $e -}}
					p.Or().EQ({{ $e.Type.Package }}.{{ $e.Type.ID.Constant }}, eid)
				}
				query, args := sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
					Set({{ $.Package }}.{{ $e.ColumnConstant }}, id).
					Where(sql.And(p, sql.IsNull({{ $.Package }}.{{ $e.ColumnConstant }}))).
					Query()
				if err := tx.Exec(ctx, query, args, &res); err != nil {
					return nil, rollback(tx, err)
				}
				affected, err := res.RowsAffected()
				if err != nil {
					return nil, rollback(tx, err)
				}
				if int(affected) < len({{ $receiver }}.{{ $e.StructField }}) {
					return nil, rollback(tx, &ErrConstraintFailed{msg: fmt.Sprintf("one of \"{{ $e.Name }}\" %v already connected to a different \"{{ $.Name }}\"", keys({{ $receiver }}.{{ $e.StructField }}))})
				}
			{{- else }}{{/* O2O */}}
				{{- if $.Type.ID.IsString }}
					eid, err := strconv.Atoi(keys({{ $receiver }}.{{ $e.StructField }})[0])
					if err != nil {
						return nil, err
					}
				{{- else }}
					eid := keys({{ $receiver }}.{{ $e.StructField }})[0]
				{{- end }}
				{{- if $e.IsInverse }}
					query, args := sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
						Set({{ $.Package }}.{{ $e.ColumnConstant }}, eid).
						Where(sql.EQ({{ $.Package }}.{{ $.ID.Constant }}, id).And().IsNull({{ $.Package }}.{{ $e.ColumnConstant }})).
						Query()
				{{- else }}
					query, args := sql.Update({{ $.Package }}.{{ $e.TableConstant }}).
						Set({{ $.Package }}.{{ $e.ColumnConstant }}, id).
						Where(sql.EQ({{ $e.Type.Package }}.{{ $e.Type.ID.Constant }}, eid).And().IsNull({{ $.Package }}.{{ $e.ColumnConstant }})).
						Query()
				{{- end }}
				if err := tx.Exec(ctx, query, args, &res); err != nil {
					return nil, rollback(tx, err)
				}
				affected, err := res.RowsAffected()
				if err != nil {
					return nil, rollback(tx, err)
				}
				if int(affected) < len({{ $receiver }}.{{ $e.StructField }}) {
					return nil, rollback(tx, &ErrConstraintFailed{msg: fmt.Sprintf("one of \"{{ $e.Name }}\" %v already connected to a different \"{{ $.Name }}\"", keys({{ $receiver }}.{{ $e.StructField }}))})
				}
			{{- end }}
		}
	{{- end }}
	if err := tx.Commit(); err != nil {
		return nil, err
	}
	return {{ $.Receiver }}, nil
}

{{ end }}

{{ define "dialect/sql/create/convertid" }}
	{{- if $.Type.ID.IsString }}
		eid, err := strconv.Atoi(eid)
		if err != nil {
			return nil, rollback(tx, err)
		}
	{{- end }}
{{ end }}