package gateway

import (
	"errors"

	protocol "git.sechmachine.io.vn/sechmachine/VerseVDI-Protocol/gen/go/protocol"
)

var ErrNoCapabilityOverlap = errors.New("no capability overlap")

func DefaultCapabilities() protocol.CapabilityProfile {
	return protocol.CapabilityProfile{
		Transport:         "quic-tls13",
		Framing:           "datagram-v1",
		Media:             "encoded",
		Audio:             "encoded",
		SourceRateControl: "server",
		ClientDecode:      "h264-opus",
	}
}

func IntersectCapabilities(profiles ...protocol.CapabilityProfile) (protocol.CapabilityProfile, error) {
	if len(profiles) == 0 {
		return protocol.CapabilityProfile{}, ErrNoCapabilityOverlap
	}
	for _, profile := range profiles {
		if err := profile.Validate(); err != nil {
			return protocol.CapabilityProfile{}, ErrNoCapabilityOverlap
		}
	}
	selected := profiles[0]
	for _, profile := range profiles[1:] {
		if selected.Transport != profile.Transport ||
			selected.Framing != profile.Framing ||
			selected.Media != profile.Media ||
			selected.Audio != profile.Audio ||
			selected.SourceRateControl != profile.SourceRateControl ||
			selected.ClientDecode != profile.ClientDecode {
			return protocol.CapabilityProfile{}, ErrNoCapabilityOverlap
		}
	}
	return selected, nil
}