package proxy

import (
	"net"
	"net/http"
	"time"

	"git.maze.io/maze/styx/proxy/policy"
	"git.maze.io/maze/styx/proxy/resolver"
)

type ConnectHandler interface {
	HandleConnect(session *Session, network, address string) net.Conn
}

// ConnectHandlerFunc is called when the proxy receives a new HTTP CONNECT request.
type ConnectHandlerFunc func(session *Session, network, address string) net.Conn

func (f ConnectHandlerFunc) HandleConnect(session *Session, network, address string) net.Conn {
	return f(session, network, address)
}

type RequestHandler interface {
	HandleRequest(session *Session) (*http.Request, *http.Response)
}

// RequestHandlerFunc is called when the proxy receives a new request.
type RequestHandlerFunc func(session *Session) (*http.Request, *http.Response)

func (f RequestHandlerFunc) HandleRequest(session *Session) (*http.Request, *http.Response) {
	return f(session)
}

type ResponseHandler interface {
	HandleResponse(session *Session) *http.Response
}

// ResponseHandler is called when the proxy receives a response.
type ResponseHandlerFunc func(session *Session) *http.Response

func (f ResponseHandlerFunc) HandleResponse(session *Session) *http.Response {
	return f(session)
}

type ErrorHandler interface {
	HandleError(session *Session, err error)
}

type ErrorHandlerFunc func(session *Session, err error)

func (f ErrorHandlerFunc) HandleError(session *Session, err error) {
	f(session, err)
}

type Config struct {
	// Listen address.
	Listen string `hcl:"listen,optional"`

	// Bind address for outgoing connections.
	Bind string `hcl:"bind,optional"`

	// Interface for outgoing connections.
	Interface string `hcl:"interface,optional"`

	// Upstream proxy servers.
	Upstream []string `hcl:"upstream,optional"`

	// DialTimeout for establishing new connections.
	DialTimeout time.Duration `hcl:"dial_timeout,optional"`

	// Policy for the proxy.
	Policy *policy.Policy `hcl:"policy,block"`

	// Resolver for the proxy.
	Resolver resolver.Resolver

	ConnectHandler  ConnectHandler
	RequestHandler  RequestHandler
	ResponseHandler ResponseHandler
	ErrorHandler    ErrorHandler
}

var (
	_ ConnectHandler  = (ConnectHandlerFunc)(nil)
	_ RequestHandler  = (RequestHandlerFunc)(nil)
	_ ResponseHandler = (ResponseHandlerFunc)(nil)
	_ ErrorHandler    = (ErrorHandlerFunc)(nil)
)