package contracts

import (
	"io"
	"net/http"

	"git.fsdpf.net/go/req"
	"github.com/samber/do/v2"
)

type EventStream interface {
	Controller
	// 获取请求信息
	Request() *http.Request
	// 请求处理
	Execute(req.GlobalParams) error
	// 获取用户信息
	User() req.User
	// 路由信息
	Route() req.Route
	// 发送数据
	Sent(data, event string) error
}

type EsHandleController struct {
	Controller
	w       http.ResponseWriter
	flusher http.Flusher
	request *http.Request
}

func (this EsHandleController) Request() *http.Request {
	return this.request
}

func (this EsHandleController) Route() req.Route {
	return this.Request().Context().Value(req.RouteCtx{Name: "Route"}).(req.Route)
}

func (this EsHandleController) User() req.User {
	return this.Request().Context().Value(req.RouteCtx{Name: "User"}).(req.User)
}

func (this EsHandleController) Execute(req.GlobalParams) error {
	return ErrFuncNotImplemented
}

func (this EsHandleController) Sent(data, event string) error {
	if _, err := io.WriteString(this.w, "event: "+event+"\ndata: "+data+"\n\n"); err != nil {
		return err
	}
	this.flusher.Flush()
	return nil
}

func NewEventStreamController(container do.Injector, request *http.Request, w http.ResponseWriter) EventStream {
	w.Header().Set("Content-Type", "text/event-stream")
	w.Header().Set("Cache-Control", "no-cache")
	w.Header().Set("Connection", "keep-alive")

	return &EsHandleController{
		Controller: &BaseController{container},
		request:    request,
		w:          w,
		flusher:    w.(http.Flusher),
	}
}