package point

import (
	"bytes"
	"database/sql/driver"
	"errors"
	"fmt"
	"strconv"

	_ "github.com/lib/pq"
)

type Point struct {
	Lat, Lng float64
}

func (p Point) Value() (driver.Value, error) {
	tuple := fmt.Sprintf("(%f, %f)", p.Lat, p.Lng)
	return driver.Value([]byte(tuple)), nil
}

func (p *Point) Scan(src interface{}) error {
	var source []byte
	var err error
	switch src.(type) {
	case string:
		source = []byte(src.(string))
	case []byte:
		source = src.([]byte)
	default:
		return errors.New("Incompatible type for Point")
	}

	lp := bytes.IndexRune(source, '(')
	c := bytes.IndexRune(source, ',')
	rp := bytes.IndexRune(source, ')')

	if lp == -1 || c == -1 || rp == -1 {
		return fmt.Errorf(
			"incorrect format from pg for Point: %s",
			source,
		)
	}

	p.Lat, err = strconv.ParseFloat(string(source[lp+1:c]), 64)
	if err != nil {
		return err
	}
	p.Lng, err = strconv.ParseFloat(string(source[c+1:rp]), 64)
	if err != nil {
		return err
	}

	return nil
}