package server

import (
	"crypto/tls"
	"fmt"
	"net"
	"time"
)

type ConnectionHandler interface {
	GetConcurrency() int
	GetKeepAlive() time.Duration
	GetHandshakeTimeout() time.Duration
	GetTLSConfig() *tls.Config

	Listener(serverCtx ServerCtx) (net.Listener, error)
}

type ConnectionHandlers struct {
	ConnectionHandler

	// The maximum number of concurrent connections the server may serve.
	//
	// DefaultConcurrency is used if not set.
	Concurrency      int
	KeepAlive        time.Duration
	HandshakeTimeout time.Duration
	TLSConfig        *tls.Config
}

func (ch *ConnectionHandlers) Listener(serverCtx ServerCtx) (net.Listener, error) {
	return nil, fmt.Errorf("Method[ConnectionHandler.Listener] is not implemented")
}

func (ch *ConnectionHandlers) GetConcurrency() int {
	return ch.Concurrency
}

func (ch *ConnectionHandlers) GetKeepAlive() time.Duration {
	return ch.KeepAlive
}

func (ch *ConnectionHandlers) GetHandshakeTimeout() time.Duration {
	return ch.HandshakeTimeout
}

func (ch *ConnectionHandlers) GetTLSConfig() *tls.Config {
	return ch.TLSConfig
}

func (ch *ConnectionHandlers) Validate() error {
	if ch.Concurrency <= 0 {
		ch.Concurrency = DefaultConcurrency
	}

	if ch.KeepAlive <= 0 {
		ch.KeepAlive = DefaultKeepAlive
	}

	if ch.HandshakeTimeout <= 0 {
		ch.HandshakeTimeout = DefaultHandshakeTimeout
	}

	return nil
}