package app

import (
	"sync"
	"time"
)

const (
	vpnLocationsCommandTimeout = 7 * time.Second
	vpnLocationsFreshTTL       = 10 * time.Minute
	vpnLocationsBackoffMin     = 2 * time.Second
	vpnLocationsBackoffMax     = 60 * time.Second
	vpnLocationsCachePath      = stateDir + "/vpn-locations-cache.json"
)

type vpnLocationItem struct {
	Label  string `json:"label"`
	ISO    string `json:"iso"`
	Target string `json:"target,omitempty"`
}

type vpnLocationsSnapshot struct {
	Locations         []vpnLocationItem `json:"locations"`
	UpdatedAt         string            `json:"updated_at,omitempty"`
	Stale             bool              `json:"stale"`
	RefreshInProgress bool              `json:"refresh_in_progress"`
	LastError         string            `json:"last_error,omitempty"`
	NextRetryAt       string            `json:"next_retry_at,omitempty"`
}

type vpnLocationsCacheDisk struct {
	Locations []vpnLocationItem `json:"locations"`
	UpdatedAt string            `json:"updated_at,omitempty"`
}

type vpnLocationsStore struct {
	mu sync.Mutex

	loaded bool

	locations []vpnLocationItem
	swr       refreshCoordinator
}

var vpnLocationCache = &vpnLocationsStore{
	swr: newRefreshCoordinator(
		vpnLocationsFreshTTL,
		vpnLocationsBackoffMin,
		vpnLocationsBackoffMax,
	),
}