package httpserver

import (
	"context"
	"crypto/tls"
	"net/http"

	"github.com/gin-gonic/gin"
	"github.com/pelletier/go-toml"
	"github.com/phuslu/log"
	"go.sebtobie.de/httpserver/auth"
	"go.sebtobie.de/httpserver/menus"
)

// Config that is used to map the toml config to the settings that are used.
type Config struct {
	Addr      string
	TLSconfig *tls.Config
	Certfile  string
	Keyfile   string
}

// MarshalLogObject adds the information over the object to the *log.Entry
func (c *Config) MarshalLogObject(e *log.Entry) {
	e.Str("Address", c.Addr).Bool("TLS", c.TLSconfig != nil).Strs("Cert", []string{c.Certfile, c.Keyfile})
}

// Server is an wrapper for the *http.Server and *gin.Engine
type Server struct {
	http            *http.Server
	conf            *Config
	router          *gin.Engine
	mrouter         map[string]*gin.Engine
	config          *toml.Tree
	authhf          auth.AuthenticationHandler
	sites           []Site
	menus           []menus.Menu
	NotFoundHandler gin.HandlerFunc
}

// StartServer starts the server as configured and sends the errormessage to the log.
func (s *Server) StartServer() {
	log.Info().Msg("Starting server")
	var err error
	if s.conf.Certfile != "" && s.conf.Keyfile != "" {
		err = s.http.ListenAndServeTLS(s.conf.Certfile, s.conf.Keyfile)

	} else {
		err = s.http.ListenAndServe()
	}
	if err != http.ErrServerClosed {
		log.Error().Err(err).Msg("Server unexpected exited")
	}
}

// DomainRouter redirects the requests to the routers of the domains
func (s *Server) DomainRouter(c *gin.Context) {
	domain := c.Request.URL.Host
	entry := log.Trace().Str("domain", domain)
	if router, found := s.mrouter[domain]; found {
		entry.Msg("Found domain")
		router.NoMethod(s.NotFoundHandler)
		router.NoRoute(s.NotFoundHandler)
		c.Set("domain", domain)
		router.HandleContext(c)
		return
	}
	entry.Interface("domains", s.mrouter).Msg("domain not found")
	s.NotFoundHandler(c)
}

// CreateServer creates an server that can be run in a coroutine.
func CreateServer(config *toml.Tree) *Server {
	log.Info().Msg("Redirect logging output to phuslu/log")
	gin.DefaultErrorWriter = log.DefaultLogger.Std(log.ErrorLevel, log.Context{}, "GIN", 0).Writer()
	gin.DefaultWriter = log.DefaultLogger.Std(log.DebugLevel, log.Context{}, "GIN", 0).Writer()
	log.Info().Msg("Creating HTTP-Server")
	var server = &Server{
		conf: &Config{
			Addr: "127.0.0.1:8080",
		},
		router:  gin.New(),
		mrouter: map[string]*gin.Engine{},
		authhf:  &auth.AnonAccountHandler{},
	}
	mw := []gin.HandlerFunc{
		func(c *gin.Context) {
			c.Set(Accounts, server.authhf.Account(c))
			c.Set(Menus, server.menus)
		},
		server.DomainRouter,
	}
	server.Use(mw...)
	server.router.RouterGroup.Handlers = mw
	if err := config.Unmarshal(server.conf); err != nil {
		log.Error().Msg("Problem mapping config to Configstruct")
	}
	log.Debug().EmbedObject(server.conf).Msg("Config")
	server.http = &http.Server{
		Addr:      server.conf.Addr,
		ErrorLog:  log.DefaultLogger.Std(log.ErrorLevel, log.Context{}, "", 0),
		Handler:   server.router,
		TLSConfig: server.conf.TLSconfig,
	}
	server.NotFoundHandler = gin.WrapH(http.NotFoundHandler())
	gin.DebugPrintRouteFunc = func(httpMethod, absolutePath, handlerName string, nuHandlers int) {
		log.Trace().Msgf("%-4s(%02d): %-20s %s", httpMethod, nuHandlers-len(mw), absolutePath, handlerName)
	}
	server.menus = []menus.Menu{}
	return server
}

// Use installs the middleware into the router.
// The Middleware must be able to detect multiple calls byy itself. Deduplication is not performed.
func (s *Server) Use(m ...gin.HandlerFunc) {
	s.router.Use(m...)
}

// UseAuthBackend is the funćtion that sets the Handler for the authentication
func (s *Server) UseAuthBackend(a auth.AuthenticationHandler) {
	s.authhf = a
}

// Stop Shuts the Server down
func (s *Server) Stop(ctx context.Context) {
	log.Info().Err(s.http.Shutdown(ctx)).Msg("Server Shut down.")
	for _, site := range s.sites {
		site.Teardown()
	}
}

// Site is an Interface to abstract the modularized group of pages.
// The Middleware must be able to detect multiple calls byy itself. Deduplication is not performed.
type Site interface {
	Init(*gin.RouterGroup)
	Teardown()
}

// RegisterSite adds an site to the engine as its own grouo
func (s *Server) RegisterSite(domain, path string, site Site) {
	var router *gin.Engine
	var found bool
	if router, found = s.mrouter[domain]; !found {
		router = gin.New()
		s.mrouter[domain] = router
	}
	site.Init(router.Group(path))
	s.sites = append(s.sites, site)
	if ms, ok := site.(menus.MenuSite); ok {
		menus := ms.Menu(domain)
		log.Debug().Msgf("%d menus are added", len(menus))
		s.menus = append(s.menus, menus...)
	}
	return
}