package server

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

	"github.com/evcc-io/evcc/core/site"
	"github.com/evcc-io/evcc/server/assets"
	"github.com/evcc-io/evcc/util"
	"github.com/evcc-io/evcc/util/telemetry"
	"github.com/go-http-utils/etag"
	"github.com/gorilla/handlers"
	"github.com/gorilla/mux"
)

type route struct {
	Methods     []string
	Pattern     string
	HandlerFunc http.HandlerFunc
}

// routeLogger traces matched routes including their executing time
//
//lint:ignore U1000 if needed
func routeLogger(inner http.Handler) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		start := time.Now()
		inner.ServeHTTP(w, r)
		log.TRACE.Printf(
			"%s\t%s\t%s",
			r.Method,
			r.RequestURI,
			time.Since(start),
		)
	}
}

// HTTPd wraps an http.Server and adds the root router
type HTTPd struct {
	*http.Server
}

// NewHTTPd creates HTTP server with configured routes for loadpoint
func NewHTTPd(addr string, hub *SocketHub) *HTTPd {
	router := mux.NewRouter().StrictSlash(true)

	// websocket
	router.HandleFunc("/ws", socketHandler(hub))

	// static - individual handlers per root and folders
	static := router.PathPrefix("/").Subrouter()
	static.Use(handlers.CompressHandler)
	static.Use(handlers.CompressHandler, func(h http.Handler) http.Handler {
		return etag.Handler(h, false)
	})

	static.HandleFunc("/", indexHandler())
	for _, dir := range []string{"assets", "meta"} {
		static.PathPrefix("/" + dir).Handler(http.FileServer(http.FS(assets.Web)))
	}
	static.PathPrefix("/i18n").Handler(http.StripPrefix("/i18n", http.FileServer(http.FS(assets.I18n))))

	srv := &HTTPd{
		Server: &http.Server{
			Addr:         addr,
			Handler:      router,
			ReadTimeout:  5 * time.Second,
			WriteTimeout: 10 * time.Second,
			IdleTimeout:  120 * time.Second,
			ErrorLog:     log.ERROR,
		},
	}
	srv.SetKeepAlivesEnabled(true)

	return srv
}

// Router returns the main router
func (s *HTTPd) Router() *mux.Router {
	return s.Handler.(*mux.Router)
}

// RegisterSiteHandlers connects the http handlers to the site
func (s *HTTPd) RegisterSiteHandlers(site site.API, cache *util.Cache) {
	router := s.Server.Handler.(*mux.Router)

	// api
	api := router.PathPrefix("/api").Subrouter()
	api.Use(jsonHandler)
	api.Use(handlers.CompressHandler)
	api.Use(handlers.CORS(
		handlers.AllowedHeaders([]string{"Content-Type"}),
	))

	// site api
	routes := map[string]route{
		"health":        {[]string{"GET"}, "/health", healthHandler(site)},
		"state":         {[]string{"GET"}, "/state", stateHandler(cache)},
		"config":        {[]string{"GET"}, "/config/templates/{class:[a-z]+}", templatesHandler},
		"products":      {[]string{"GET"}, "/config/products/{class:[a-z]+}", productsHandler},
		"test":          {[]string{"POST"}, "/config/test/{class:[a-z]+}", testHandler},
		"buffersoc":     {[]string{"POST", "OPTIONS"}, "/buffersoc/{value:[0-9.]+}", floatHandler(site.SetBufferSoc, site.GetBufferSoc)},
		"prioritysoc":   {[]string{"POST", "OPTIONS"}, "/prioritysoc/{value:[0-9.]+}", floatHandler(site.SetPrioritySoc, site.GetPrioritySoc)},
		"residualpower": {[]string{"POST", "OPTIONS"}, "/residualpower/{value:[-0-9.]+}", floatHandler(site.SetResidualPower, site.GetResidualPower)},
		"tariff":        {[]string{"GET"}, "/tariff/{tariff:[a-z]+}", tariffHandler(site)},
		"sessions":      {[]string{"GET"}, "/sessions", sessionHandler},
		"session1":      {[]string{"PUT"}, "/session/{id:[0-9]+}", updateSessionHandler},
		"session2":      {[]string{"DELETE"}, "/session/{id:[0-9]+}", deleteSessionHandler},
		"telemetry":     {[]string{"GET"}, "/settings/telemetry", boolGetHandler(telemetry.Enabled)},
		"telemetry2":    {[]string{"POST", "OPTIONS"}, "/settings/telemetry/{value:[a-z]+}", boolHandler(telemetry.Enable, telemetry.Enabled)},
	}

	for _, r := range routes {
		api.Methods(r.Methods...).Path(r.Pattern).Handler(r.HandlerFunc)
	}

	// loadpoint api
	for id, lp := range site.Loadpoints() {
		loadpoint := api.PathPrefix(fmt.Sprintf("/loadpoints/%d", id+1)).Subrouter()

		routes := map[string]route{
			"mode":             {[]string{"POST", "OPTIONS"}, "/mode/{value:[a-z]+}", chargeModeHandler(lp)},
			"minsoc":           {[]string{"POST", "OPTIONS"}, "/minsoc/{value:[0-9]+}", intHandler(pass(lp.SetMinSoc), lp.GetMinSoc)},
			"mincurrent":       {[]string{"POST", "OPTIONS"}, "/mincurrent/{value:[0-9.]+}", floatHandler(pass(lp.SetMinCurrent), lp.GetMinCurrent)},
			"maxcurrent":       {[]string{"POST", "OPTIONS"}, "/maxcurrent/{value:[0-9.]+}", floatHandler(pass(lp.SetMaxCurrent), lp.GetMaxCurrent)},
			"phases":           {[]string{"POST", "OPTIONS"}, "/phases/{value:[0-9]+}", phasesHandler(lp)},
			"targetenergy":     {[]string{"POST", "OPTIONS"}, "/target/energy/{value:[0-9.]+}", floatHandler(pass(lp.SetTargetEnergy), lp.GetTargetEnergy)},
			"targetsoc":        {[]string{"POST", "OPTIONS"}, "/target/soc/{value:[0-9]+}", intHandler(pass(lp.SetTargetSoc), lp.GetTargetSoc)},
			"targettime":       {[]string{"POST", "OPTIONS"}, "/target/time/{time:[0-9TZ:.-]+}", targetTimeHandler(lp)},
			"targettime2":      {[]string{"DELETE", "OPTIONS"}, "/target/time", targetTimeRemoveHandler(lp)},
			"plan":             {[]string{"GET"}, "/target/plan", planHandler(lp)},
			"vehicle":          {[]string{"POST", "OPTIONS"}, "/vehicle/{vehicle:[1-9][0-9]*}", vehicleHandler(site, lp)},
			"vehicle2":         {[]string{"DELETE", "OPTIONS"}, "/vehicle", vehicleRemoveHandler(lp)},
			"vehicleDetect":    {[]string{"PATCH", "OPTIONS"}, "/vehicle", vehicleDetectHandler(lp)},
			"remotedemand":     {[]string{"POST", "OPTIONS"}, "/remotedemand/{demand:[a-z]+}/{source::[0-9a-zA-Z_-]+}", remoteDemandHandler(lp)},
			"enableThreshold":  {[]string{"POST", "OPTIONS"}, "/enable/threshold/{value:-?[0-9.]+}", floatHandler(pass(lp.SetEnableThreshold), lp.GetEnableThreshold)},
			"disableThreshold": {[]string{"POST", "OPTIONS"}, "/disable/threshold/{value:-?[0-9.]+}", floatHandler(pass(lp.SetDisableThreshold), lp.GetDisableThreshold)},
		}

		for _, r := range routes {
			loadpoint.Methods(r.Methods...).Path(r.Pattern).Handler(r.HandlerFunc)
		}
	}
}

// RegisterShutdownHandler connects the http handlers to the site
func (s *HTTPd) RegisterShutdownHandler(callback func()) {
	router := s.Server.Handler.(*mux.Router)

	// api
	api := router.PathPrefix("/api").Subrouter()
	api.Use(jsonHandler)
	api.Use(handlers.CompressHandler)
	api.Use(handlers.CORS(
		handlers.AllowedHeaders([]string{"Content-Type"}),
	))

	// site api
	routes := map[string]route{
		"shutdown": {[]string{"POST", "OPTIONS"}, "/shutdown", func(w http.ResponseWriter, r *http.Request) {
			callback()
			w.WriteHeader(http.StatusNoContent)
		}},
	}

	for _, r := range routes {
		api.Methods(r.Methods...).Path(r.Pattern).Handler(r.HandlerFunc)
	}
}