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2019-06-03 09:32:43 +00:00
package arn
import "math"
// EarthRadius is the radius of the earth in kilometers.
const EarthRadius = 6371
// Location ...
type Location struct {
CountryName string `json:"countryName"`
CountryCode string `json:"countryCode"`
Latitude float64 `json:"latitude" editable:"true"`
Longitude float64 `json:"longitude" editable:"true"`
CityName string `json:"cityName"`
RegionName string `json:"regionName"`
TimeZone string `json:"timeZone"`
ZipCode string `json:"zipCode"`
}
// IPInfoDBLocation ...
type IPInfoDBLocation struct {
CountryName string `json:"countryName"`
CountryCode string `json:"countryCode"`
Latitude string `json:"latitude"`
Longitude string `json:"longitude"`
CityName string `json:"cityName"`
RegionName string `json:"regionName"`
TimeZone string `json:"timeZone"`
ZipCode string `json:"zipCode"`
}
// IsValid returns true if latitude and longitude are available.
func (p *Location) IsValid() bool {
return p.Latitude != 0 && p.Longitude != 0
}
// Distance calculates the distance in kilometers to the second location.
// Original implementation: https://www.movable-type.co.uk/scripts/latlong.html
func (p *Location) Distance(p2 *Location) float64 {
dLat := (p2.Latitude - p.Latitude) * (math.Pi / 180.0)
dLon := (p2.Longitude - p.Longitude) * (math.Pi / 180.0)
lat1 := p.Latitude * (math.Pi / 180.0)
lat2 := p2.Latitude * (math.Pi / 180.0)
a1 := math.Sin(dLat/2) * math.Sin(dLat/2)
a2 := math.Sin(dLon/2) * math.Sin(dLon/2) * math.Cos(lat1) * math.Cos(lat2)
a := a1 + a2
c := 2 * math.Atan2(math.Sqrt(a), math.Sqrt(1-a))
return EarthRadius * c
}