package mesh

import (
	"context"
	"crypto/tls"
	"fmt"
	"net/http"
	"strings"
	"time"

	"github.com/example/remote-access-platform/agents/rap-node-agent/internal/fabricproto"
)

type FabricTransportSession interface {
	Send(context.Context, fabricproto.Frame) error
	Frames() <-chan fabricproto.Frame
	Errors() <-chan error
	Close() error
	Closed() bool
}

type FabricTransport interface {
	Connect(context.Context, FabricTransportTarget) (FabricTransportSession, error)
	Close() error
}

type FabricTransportTarget struct {
	EndpointID     string
	PeerID         string
	Endpoint       string
	Transport      string
	Token          string
	Header         http.Header
	TLSConfig      *tls.Config
	PeerCertSHA256 string
	Timeout        time.Duration
	MaxPayload     int
	OutboundBuffer int
	InboundBuffer  int
	ErrorBuffer    int
}

func FabricTransportForTarget(target FabricTransportTarget, quicTransport *QUICFabricTransport) (FabricTransport, FabricTransportTarget, error) {
	transportLabel := strings.ToLower(strings.TrimSpace(target.Transport))
	endpoint := strings.TrimSpace(target.Endpoint)
	if strings.HasPrefix(strings.ToLower(endpoint), "quic://") {
		if transportLabel == "" {
			transportLabel = "quic"
		}
		target.Endpoint = strings.TrimPrefix(endpoint, "quic://")
	}
	switch transportLabel {
	case "quic", "direct_quic", "udp_quic", "quic_udp", "lan_quic", "reverse_quic", "relay_quic", "ice_quic":
		if quicTransport == nil {
			quicTransport = NewQUICFabricTransport(nil)
		}
		return quicTransport, target, nil
	default:
		return nil, target, fmt.Errorf("unsupported fabric transport %q: quic is required", target.Transport)
	}
}