package convx

import (
	"strconv"

	"errors"
)

// interface 转 float64
func ToFloat64(val interface{}) (f float64, err error) {

	switch v := val.(type) {
	case nil:
		return 0, errors.New("val is nil")
	case float32:
		return float64(v), nil
	case float64:
		return v, nil
	case int:
		return float64(v), nil
	case int8:
		return float64(v), nil
	case int16:
		return float64(v), nil
	case int32:
		return float64(v), nil
	case int64:
		return float64(v), nil
	case uint:
		return float64(v), nil
	case uint8:
		return float64(v), nil
	case uint16:
		return float64(v), nil
	case uint32:
		return float64(v), nil
	case uint64:
		return float64(v), nil
	case string:
		return strconv.ParseFloat(v, 64)
	case bool:
		if v {
			return 1, nil
		} else {
			return 0, nil
		}
	case []byte:
		return strconv.ParseFloat(string(v), 64)
	}

	return 0, errors.New("convx.ToFloat64: unknown type")
}