package http

import (
	"context"
	"errors"
	"fmt"
	"ims/app/http/middleware"
	"ims/app/http/routes"
	"ims/util/log"
	"net/http"

	"zestack.dev/env"
	"zestack.dev/slim"
)

var (
	started chan struct{}
	exit    chan chan error
)

func init() {
	started = make(chan struct{})
	exit = make(chan chan error)
}

func Start(ctx context.Context) error {
	select {
	case <-started:
		return errors.New("app: server already started")
	default:
		close(started)
	}

	app := createKernel()
	srv := createServer(app)
	routes.Init(app)

	go func() {
		if srvErr := app.StartServer(srv); srvErr != nil {
			log.Error("encountered an error while serving listener: ", srvErr)
		}
	}()

	go func() {
		// 监听停止命令，停止网络服务
		errChan := <-exit
		// 停止 slim 应用
		errChan <- app.Close()
	}()

	return nil
}

func createKernel() *slim.Slim {
	app := slim.New()
	app.Debug = !env.IsEnv("prod")
	app.Logger = log.Default()
	app.ErrorHandler = middleware.ErrorHandler
	app.ResetRouterCreator(func(s *slim.Slim) slim.Router {
		return slim.NewRouter(slim.RouterConfig{
			RoutingTrailingSlash: true,
		})
	})
	app.Use(slim.Logging())
	app.Use(slim.Recovery())
	app.Use(middleware.CORSWithConfig(middleware.CORSConfig{
		AllowOrigins:     env.List("CORS_ALLOW_ORIGINS"),
		AllowMethods:     env.List("CORS_ALLOW_METHODS"),
		AllowHeaders:     env.List("CORS_ALLOW_HEADERS"),
		AllowCredentials: env.Bool("CORS_ALLOW_CREDENTIALS"),
		ExposeHeaders:    env.List("CORS_EXPOSE_HEADERS"),
		MaxAge:           env.Int("CORS_MAX_AGE"),
	}))
	return app
}

func createServer(app *slim.Slim) *http.Server {
	// TODO 支持 TLSConfig 配置
	return &http.Server{
		Addr:              fmt.Sprintf("%s:%d", env.String("SERVER_ADDR"), env.Int("SERVER_PORT", 1234)),
		Handler:           app,
		ReadTimeout:       env.Duration("HTTP_READ_TIMEOUT", 0),
		ReadHeaderTimeout: env.Duration("HTTP_READ_HEADER_TIMEOUT", 0),
		WriteTimeout:      env.Duration("HTTP_WRITE_TIMEOUT", 0),
		IdleTimeout:       env.Duration("HTTP_IDLE_TIMEOUT", 0),
		MaxHeaderBytes:    env.Int("HTTP_MAX_HEADER_BYTES", http.DefaultMaxHeaderBytes),
	}
}

func Stop() error {
	select {
	case <-started:
		errCh := make(chan error)
		exit <- errCh
		return <-errCh
	default:
		return nil
	}
}