lt.go

package connor

import (
	"fmt"
	"time"

	"github.com/SierraSoftworks/connor/internal/numbers"
)

func init() {
	Register(&LessOperator{})
}

// LessOperator does value comparisons to determine whether one
// value is strictly less than another.
type LessOperator struct {
}

func (o *LessOperator) Name() string {
	return "lt"
}

func (o *LessOperator) Evaluate(condition, data interface{}) (bool, error) {
	switch cn := numbers.TryUpcast(condition).(type) {
	case string:
		switch dn := data.(type) {
		case string:
			return dn < cn, nil
		}
		return false, nil
	case float64:
		switch dn := numbers.TryUpcast(data).(type) {
		case float64:
			return dn < cn, nil
		case int64:
			return float64(dn) < cn, nil
		}

		return false, nil
	case int64:
		switch dn := numbers.TryUpcast(data).(type) {
		case float64:
			return dn < float64(cn), nil
		case int64:
			return dn < cn, nil
		}

		return false, nil
	case time.Time:
		switch dn := data.(type) {
		case time.Time:
			return dn.Before(cn), nil
		}
		return false, nil
	default:
		return false, fmt.Errorf("unknown comparison type '%#v'", condition)
	}
}