package server

import (
	"context"
	"io/fs"
	"net/http"
	"os"
	"os/signal"
	"sync"
	"time"

	"github.com/labstack/echo/v4"

	"dynatron.me/x/blasphem/internal/common"
	"dynatron.me/x/blasphem/pkg/auth"
	"dynatron.me/x/blasphem/pkg/blas"
	"dynatron.me/x/blasphem/pkg/config"
	"dynatron.me/x/blasphem/pkg/frontend"
)

const LogHeader = `${time_rfc3339} ${level} ${prefix} ${short_file}:${line}`

type Server struct {
	*blas.Blas
	*echo.Echo
	auth.Authenticator
	rootFS fs.FS
	wg     sync.WaitGroup
}

func (s *Server) installRoutes() {
	s.GET("/", echo.WrapHandler(frontend.FSHandler))
	s.GET("/api/websocket", s.wsHandler)
	s.GET("/auth/authorize", s.AuthorizeHandler)
	s.GET("/auth/providers", s.ProvidersHandler)

	s.POST("/auth/login_flow", s.LoginFlowHandler)
	s.POST("/auth/login_flow/:flow_id", s.LoginFlowHandler)
	s.DELETE("/auth/login_flow/:flow_id", s.LoginFlowDeleteHandler)
}

func New(cfg *config.Config) (s *Server, err error) {
	b, err := blas.New(cfg)
	if err != nil {
		return nil, err
	}

	s = &Server{
		Blas: b,
		Echo: echo.New(),
	}
	err = s.InitAuth(b.Store)
	if err != nil {
		return s, err
	}

	s.Echo.Debug = true
	s.Echo.HideBanner = true
	s.Echo.Logger.SetPrefix(common.AppName)
	s.Echo.Logger.SetHeader(LogHeader)

	s.installRoutes()

	return s, nil
}

func (s *Server) Shutdown(ctx context.Context) error {
	err := s.Blas.Shutdown(ctx)
	if err != nil {
		return err
	}

	return s.Echo.Shutdown(ctx)
}

func (s *Server) Go() error {
	s.wg.Add(1)
	go func() {
		err := s.Start(s.Config.Server.Bind)
		if err != nil && err != http.ErrServerClosed {
			s.Logger.Fatal(err)
		}

		s.wg.Done()
	}()

	// Wait for interrupt signal to gracefully shutdown the server with a timeout of 10 seconds.
	// Use a buffered channel to avoid missing signals as recommended for signal.Notify
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, os.Interrupt)
	<-quit
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := s.Shutdown(ctx); err != nil {
		s.Logger.Fatal(err)
	}

	s.wg.Wait()
	s.Logger.Info("shutdown complete")

	return nil
}