package rest

import (
	"crypto/tls"
	"git.diulo.com/mogfee/kit/rest/chain"
	"git.diulo.com/mogfee/kit/rest/httpx"
	"git.diulo.com/mogfee/kit/rest/internal"
	"net/http"
	"time"
)

type engine struct {
	conf        RestConf
	routes      []featureRoutes
	timeout     time.Duration
	chain       chain.Chain
	middlewares []Middleware
	tlsConfig   *tls.Config
}

func newEngine(c RestConf) *engine {
	srv := &engine{
		conf:        c,
		timeout:     time.Duration(c.Timeout),
		middlewares: make([]Middleware, 0),
	}
	return srv
}
func (n *engine) addRoutes(r featureRoutes) {
	n.routes = append(n.routes, r)
	if r.timeout > n.timeout {
		n.timeout = r.timeout
	}
}
func (n *engine) bindRoutes(router httpx.Router) error {
	for _, fr := range n.routes {
		for _, route := range fr.routes {
			if err := n.bindRoute(fr, router, route); err != nil {
				return err
			}
		}
	}
	return nil
}

func (n *engine) bindRoute(fr featureRoutes, router httpx.Router, route Route) error {
	chn := n.chain
	if chn == nil {
		chn = n.buildChainWithNativeMiddlewares(fr, route)
	}
	for _, middleware := range n.middlewares {
		chn = chn.Append(convertMiddleware(middleware))
	}
	handle := chn.ThenFunc(route.Handler)
	return router.Handle(route.Method, route.Path, handle)
}
func (n *engine) buildChainWithNativeMiddlewares(fr featureRoutes, route Route) chain.Chain {
	chn := chain.New()
	return chn
}

func convertMiddleware(ware Middleware) func(http.Handler) http.Handler {
	return func(handler http.Handler) http.Handler {
		return ware(handler.ServeHTTP)
	}
}
func (n *engine) start(router httpx.Router) error {
	err := n.bindRoutes(router)
	if err != nil {
		return err
	}
	if len(n.conf.CertFile) == 0 && len(n.conf.KeyFile) == 0 {
		return internal.StartHttp(n.conf.Host, n.conf.Port, router, n.withTimeout())
	}
	return internal.StartHttps(n.conf.Host, n.conf.Port, n.conf.CertFile,
		n.conf.KeyFile, router, func(svr *http.Server) {
			if n.tlsConfig != nil {
				svr.TLSConfig = n.tlsConfig
			}
		}, n.withTimeout())
}
func (n *engine) withTimeout() internal.StartOption {
	return func(svr *http.Server) {
		timeout := n.timeout
		if timeout > 0 {
			svr.ReadTimeout = 4 * timeout / 5
			svr.WriteTimeout = 11 * timeout / 10
		}
	}
}
func (n *engine) use(middleware ...Middleware) {
	n.middlewares = append(n.middlewares, middleware...)
}