Maint: port forwarding refactoring (#543)

- portforward package
- portforward run loop
- Less functional arguments and cycles

internal/portforward/loop.go

@@ -0,0 +1,71 @@
+package portforward
+
+import (
+	"net/http"
+	"sync"
+	"time"
+
+	"github.com/qdm12/gluetun/internal/configuration"
+	"github.com/qdm12/gluetun/internal/constants"
+	"github.com/qdm12/gluetun/internal/firewall"
+	"github.com/qdm12/gluetun/internal/loopstate"
+	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/portforward/state"
+	"github.com/qdm12/golibs/logging"
+)
+
+var _ Looper = (*Loop)(nil)
+
+type Looper interface {
+	Runner
+	loopstate.Getter
+	StartStopper
+	SettingsGetSetter
+	Getter
+}
+
+type Loop struct {
+	statusManager loopstate.Manager
+	state         state.Manager
+	// Objects
+	client      *http.Client
+	portAllower firewall.PortAllower
+	logger      logging.Logger
+	// Internal channels and locks
+	start       chan struct{}
+	running     chan models.LoopStatus
+	stop        chan struct{}
+	stopped     chan struct{}
+	startMu     sync.Mutex
+	backoffTime time.Duration
+	userTrigger bool
+}
+
+const defaultBackoffTime = 5 * time.Second
+
+func NewLoop(settings configuration.PortForwarding,
+	client *http.Client, portAllower firewall.PortAllower,
+	logger logging.Logger) *Loop {
+	start := make(chan struct{})
+	running := make(chan models.LoopStatus)
+	stop := make(chan struct{})
+	stopped := make(chan struct{})
+
+	statusManager := loopstate.New(constants.Stopped, start, running, stop, stopped)
+	state := state.New(statusManager, settings)
+
+	return &Loop{
+		statusManager: statusManager,
+		state:         state,
+		// Objects
+		client:      client,
+		portAllower: portAllower,
+		logger:      logger,
+		start:       start,
+		running:     running,
+		stop:        stop,
+		stopped:     stopped,
+		userTrigger: true,
+		backoffTime: defaultBackoffTime,
+	}
+}