package server

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

	"code.thetadev.de/TSGRain/SEBRAUC/src/rauc"
	"code.thetadev.de/TSGRain/SEBRAUC/src/sysinfo"
	"code.thetadev.de/TSGRain/SEBRAUC/src/util"
	"code.thetadev.de/TSGRain/SEBRAUC/ui"
	"github.com/gofiber/fiber/v2"
	"github.com/gofiber/fiber/v2/middleware/compress"
	"github.com/gofiber/fiber/v2/middleware/cors"
	"github.com/gofiber/fiber/v2/middleware/filesystem"
	"github.com/gofiber/fiber/v2/middleware/logger"
	"github.com/gofiber/websocket/v2"
	"github.com/google/uuid"
)

type SEBRAUCServer struct {
	address     string
	raucUpdater *rauc.Rauc
	hub         *MessageHub
	tmpdir      string
}

type statusMessage struct {
	Success bool   `json:"success"`
	Msg     string `json:"msg"`
}

func NewServer(address string) *SEBRAUCServer {
	hub := NewHub()

	raucUpdater := rauc.NewRauc(hub.Broadcast)

	tmpdir, err := util.GetTmpdir()
	if err != nil {
		panic(err)
	}

	return &SEBRAUCServer{
		address:     address,
		raucUpdater: raucUpdater,
		hub:         hub,
		tmpdir:      tmpdir,
	}
}

func (srv *SEBRAUCServer) Run() error {
	app := fiber.New(fiber.Config{
		AppName:               "SEBRAUC",
		BodyLimit:             1024 * 1024 * 1024,
		ErrorHandler:          errorHandler,
		DisableStartupMessage: true,
	})

	app.Use(logger.New())

	app.Use(compress.New(compress.Config{
		Next: func(c *fiber.Ctx) bool {
			return strings.HasPrefix(c.Path(), "/api")
		},
	}))

	// just for testing
	app.Use("/api", cors.New())

	app.Use("/api/ws", func(c *fiber.Ctx) error {
		// IsWebSocketUpgrade returns true if the client
		// requested upgrade to the WebSocket protocol.
		if websocket.IsWebSocketUpgrade(c) {
			c.Locals("allowed", true)
			return c.Next()
		}
		return fiber.ErrUpgradeRequired
	})

	app.Use("/", filesystem.New(filesystem.Config{
		Root:       http.FS(ui.Assets),
		PathPrefix: ui.AssetsDir,
		MaxAge:     7200,
	}))

	// ROUTES
	app.Get("/api/ws", websocket.New(srv.hub.Handler))
	app.Post("/api/update", srv.controllerUpdate)
	app.Get("/api/status", srv.controllerStatus)
	app.Get("/api/info", srv.controllerInfo)
	app.Post("/api/reboot", srv.controllerReboot)

	// Start messaging hub
	go srv.hub.Run()

	return app.Listen(srv.address)
}

func (srv *SEBRAUCServer) controllerUpdate(c *fiber.Ctx) error {
	file, err := c.FormFile("updateFile")
	if err != nil {
		return err
	}

	uid, err := uuid.NewRandom()
	if err != nil {
		return err
	}

	updateFile := fmt.Sprintf("%s/update_%s.raucb", srv.tmpdir, uid.String())

	err = c.SaveFile(file, updateFile)
	if err != nil {
		return err
	}

	err = srv.raucUpdater.RunRauc(updateFile)
	if err == nil {
		writeStatus(c, true, "Update started")
	} else if errors.Is(err, util.ErrAlreadyRunning) {
		return fiber.NewError(fiber.StatusConflict, "already running")
	} else {
		return err
	}
	return nil
}

func (srv *SEBRAUCServer) controllerStatus(c *fiber.Ctx) error {
	c.Context().SetStatusCode(200)
	_ = c.JSON(srv.raucUpdater.GetStatus())
	return nil
}

func (srv *SEBRAUCServer) controllerInfo(c *fiber.Ctx) error {
	info, err := sysinfo.GetSysinfo()
	if err != nil {
		return err
	}

	c.Context().SetStatusCode(200)
	_ = c.JSON(info)
	return nil
}

func (srv *SEBRAUCServer) controllerReboot(c *fiber.Ctx) error {
	go util.Reboot(5 * time.Second)

	writeStatus(c, true, "System is rebooting")
	return nil
}

func errorHandler(c *fiber.Ctx, err error) error {
	// API error handling
	if strings.HasPrefix(c.Path(), "/api") {
		writeStatus(c, false, err.Error())
	}
	return err
}

func writeStatus(c *fiber.Ctx, success bool, msg string) {
	_ = c.JSON(statusMessage{
		Success: success,
		Msg:     msg,
	})

	if success {
		c.Context().SetStatusCode(200)
	}
}