jet/sqlbuilder/clause.go

package sqlbuilder

import (
	"bytes"
	"errors"
	"strconv"
)

type serializeOption int

const (
	SKIP_DEFAULT_ALIASING = iota
	FOR_PROJECTION
	NO_TABLE_NAME
)

type Clause interface {
	Serialize(out *queryData, options ...serializeOption) error
}

type queryData struct {
	buff bytes.Buffer
	args []interface{}
}

func (q *queryData) Write(data []byte) {
	q.buff.Write(data)
}

func (q *queryData) WriteString(str string) {
	q.buff.WriteString(str)
}

func (q *queryData) WriteByte(b byte) {
	q.buff.WriteByte(b)
}

func (q *queryData) InsertArgument(arg interface{}) {
	q.args = append(q.args, arg)
	argPlaceholder := "$" + strconv.Itoa(len(q.args))

	q.buff.WriteString(argPlaceholder)
}

func (q *queryData) Reset() {
	q.buff.Reset()
	q.args = []interface{}{}
}

func argToString(value interface{}) (string, error) {
	switch bindVal := value.(type) {
	case bool:
		if bindVal {
			return "TRUE", nil
		} else {
			return "FALSE", nil
		}
	case int8:
		return strconv.FormatInt(int64(bindVal), 10), nil
	case int:
		return strconv.FormatInt(int64(bindVal), 10), nil
	case int16:
		return strconv.FormatInt(int64(bindVal), 10), nil
	case int32:
		return strconv.FormatInt(int64(bindVal), 10), nil
	case int64:
		return strconv.FormatInt(int64(bindVal), 10), nil

	case uint8:
		return strconv.FormatUint(uint64(bindVal), 10), nil
	case uint:
		return strconv.FormatUint(uint64(bindVal), 10), nil
	case uint16:
		return strconv.FormatUint(uint64(bindVal), 10), nil
	case uint32:
		return strconv.FormatUint(uint64(bindVal), 10), nil
	case uint64:
		return strconv.FormatUint(uint64(bindVal), 10), nil

	case float32:
		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64), nil
	case float64:
		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64), nil

	case string:
		return bindVal, nil
	case []byte:
		return string(bindVal), nil
		//TODO: implement
	//case time.Time:
	//	return bindVal.String())
	default:
		return "", errors.New("Unsupported literal type. ")
	}
}

func contains(s []serializeOption, e serializeOption) bool {
	for _, a := range s {
		if a == e {
			return true
		}
	}
	return false
}