// package kbus_http -- шина сообщений поверх HTTP.
package kbus_http

import (
	"fmt"
	"net/http"
	"sync"

	"github.com/gofiber/fiber/v3"

	mKs "gitp78su.ipnodns.ru/svi/kern/v4/lev0/kspec"
	mL1 "gitp78su.ipnodns.ru/svi/kern/v4/lev1"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev1/kbus_msg/msg_pub"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev1/kbus_msg/msg_serve"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev1/kbus_msg/msg_sub"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev1/kbus_msg/msg_unsub"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev2/kbus_base"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev2/kctx"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev2/kserv_http"
	"gitp78su.ipnodns.ru/svi/kern/v4/lev2/mock_hand_sub_http"
)

// kBusHttp -- шина данных поверх HTTP.
type kBusHttp struct {
	*kbus_base.KBusBase
	log mKs.ILogBuf
}

var (
	Bus_  *kBusHttp
	block sync.Mutex
)

// GetKernelBusHttp -- возвращает шину HTTP.
func GetKernelBusHttp() mKs.IKernelBus {
	block.Lock()
	defer block.Unlock()
	if Bus_ != nil {
		return Bus_
	}
	log := mL1.NewLogBuf(mL1.OptIsTerm(true), mL1.OptPrefix("kBusHttp"))
	log.Debug("GetKernelBusHttp(): new")
	kCtx := kctx.GetKernelCtx()
	kBus := kbus_base.GetKernelBusBase()
	sf := &kBusHttp{
		KBusBase: kBus,
		log:      log,
	}
	kServHttp := kserv_http.GetKernelServHttp()
	fibApp := kServHttp.Fiber()
	fibApp.Post("/bus/sub", sf.postSub)             // Топик подписки, IN
	fibApp.Post("/bus/unsub", sf.postUnsub)         // Топик отписки, IN
	fibApp.Post("/bus/request", sf.postSendRequest) // Топик входящих запросов, IN
	fibApp.Post("/bus/pub", sf.postPublish)         // Топик публикаций подписки, IN
	kCtx.Set("kernBus", sf, "GetKernelBusHttp(): http data bus")
	Bus_ = sf
	return Bus_
}

// Входящий запрос HTTP на подписку.
func (sf *kBusHttp) postSub(ctx fiber.Ctx) error {
	sf.log.Debug("postSub()")
	ctx.Set("Content-type", "text/html; charset=utf8")
	ctx.Set("Content-type", "text/json")
	ctx.Set("Cache-Control", "no-cache")
	sf.log.Debug("postSub()")
	req := &msg_sub.SubscribeReq{}
	err := ctx.Bind().Body(req)
	if err != nil {
		resp := &msg_sub.SubscribeResp{
			Status_: fmt.Sprintf("kernelBusHttp.postSub(): in parse request, err=\n\t%v\n", err),
			Uuid_:   req.Uuid_,
		}
		resp.SelfCheck()
		ctx.Response().SetStatusCode(http.StatusBadRequest)
		sf.log.Err("postSub(): in body parser, status=%q", resp.Status_)
		return ctx.JSON(resp)
	}
	resp := sf.processSubscribe(req)
	resp.SelfCheck()
	return ctx.JSON(resp)
}

// Процесс подписки веб-хука.
func (sf *kBusHttp) processSubscribe(req *msg_sub.SubscribeReq) *msg_sub.SubscribeResp {
	req.SelfCheck()
	handler := mock_hand_sub_http.NewMockHandSubHttp(req.Topic_, req.WebHook_)
	resp := &msg_sub.SubscribeResp{
		Status_: "ok",
		Uuid_:   req.Uuid_,
		Name_:   handler.Name(),
	}
	res := sf.Subscribe(handler)
	if res.IsErr() {
		resp.Status_ = fmt.Sprintf("kernelBusHttp.processSubscribe(): err=\n\t%v", res.Err())
		return resp
	}
	return resp
}

// Входящая публикация.
func (sf *kBusHttp) postPublish(ctx fiber.Ctx) error {
	sf.log.Debug("postPublish()")
	ctx.Set("Content-type", "text/html; charset=utf8")
	ctx.Set("Content-type", "text/json")
	ctx.Set("Cache-Control", "no-cache")
	req := &msg_pub.PublishReq{}
	err := ctx.Bind().Body(req)
	if err != nil {
		resp := &msg_pub.PublishResp{
			Status_: fmt.Sprintf("kernelBusHttp.postPublish(): in parse request, err=\n\t%v\n", err),
			Uuid_:   req.Uuid_,
		}
		resp.SelfCheck()
		ctx.Response().SetStatusCode(http.StatusBadRequest)
		sf.log.Err("postPublish(): in body parser, status=%v", resp.Status_)
		return ctx.JSON(resp)
	}
	resp := sf.processPublish(req)
	resp.SelfCheck()
	return ctx.JSON(resp)
}

// Выполняет процесс публикации.
func (sf *kBusHttp) processPublish(req *msg_pub.PublishReq) *msg_pub.PublishResp {
	req.SelfCheck()
	res := sf.Publish(req.Topic_, req.BinMsg_)
	resp := &msg_pub.PublishResp{
		Status_: "ok",
		Uuid_:   req.Uuid_,
	}
	if res.IsErr() {
		resp.Status_ = fmt.Sprintf("kernelBusHttp.processPublish(): err=\n\t%v", res.Err())
		return resp
	}
	return resp
}

// Входящий запрос.
func (sf *kBusHttp) postSendRequest(ctx fiber.Ctx) error {
	sf.log.Debug("postSendRequest()")
	ctx.Set("Content-type", "text/html; charset=utf8")
	ctx.Set("Content-type", "text/json")
	ctx.Set("Cache-Control", "no-cache")
	req := &msg_serve.ServeReq{}
	err := ctx.Bind().Body(req)
	if err != nil {
		resp := &msg_serve.ServeResp{
			Status_: fmt.Sprintf("kernelBusHttp.postSendRequest(): err=\n\t%v", err),
			Uuid_:   req.Uuid_,
		}
		resp.SelfCheck()
		ctx.Response().SetStatusCode(http.StatusBadRequest)
		sf.log.Err("postSendRequest(): in body parser, status=%v", resp.Status_)
		return ctx.JSON(resp)
	}
	resp := sf.processSendRequest(req)
	resp.SelfCheck()
	return ctx.JSON(resp)
}

// Обрабатывает входящий запрос.
func (sf *kBusHttp) processSendRequest(req *msg_serve.ServeReq) *msg_serve.ServeResp {
	req.SelfCheck()
	res := sf.SendRequest(req.Topic_, req.BinReq_)
	resp := &msg_serve.ServeResp{
		Status_: "ok",
		Uuid_:   req.Uuid_,
	}
	if res.IsErr() {
		resp.Status_ = fmt.Sprintf("kernelBusHttp.processSendRequest(): err=\n\t%v", res.Err())
		return resp
	}
	resp.BinResp_ = res.Ok()
	return resp
}

// Входящая отписка от топика по HTTP.
func (sf *kBusHttp) postUnsub(ctx fiber.Ctx) error {
	sf.log.Debug("postUnsub()")
	ctx.Set("Content-type", "text/html; charset=utf8")
	ctx.Set("Content-type", "text/json")
	ctx.Set("Cache-Control", "no-cache")
	req := &msg_unsub.UnsubReq{}
	err := ctx.Bind().Body(req)
	if err != nil {
		resp := &msg_serve.ServeResp{
			Status_: fmt.Sprintf("kernelBusHttp.postSendRequest(): err=\n\t%v", err),
			Uuid_:   req.Uuid_,
		}
		resp.SelfCheck()
		ctx.Response().SetStatusCode(http.StatusBadRequest)
		sf.log.Err("postUnsub(): in body_parser, status=%q", resp.Status_)
		return ctx.JSON(resp)
	}
	resp := sf.processUnsubRequest(req)
	resp.SelfCheck()
	return ctx.JSON(resp)
}

// Процесс отписки от топика.
func (sf *kBusHttp) processUnsubRequest(req *msg_unsub.UnsubReq) *msg_unsub.UnsubResp {
	req.SelfCheck()
	resp := &msg_unsub.UnsubResp{
		Status_: "ok",
		Uuid_:   req.Uuid_,
	}
	optHandler := sf.KCtx_.Get(req.Name_.Get())
	if optHandler.IsNone() {
		resp.Status_ = fmt.Sprintf("kernelBusHttp.processUnsubRequest(): not get handler(%v) from kernel ctx",
			req.Name_)
		return resp
	}
	if optHandler == nil {
		resp.Status_ = fmt.Sprintf("kernelBusHttp.processUnsubRequest(): handler(%v) not exists", req.Name_)
		return resp
	}
	hand := optHandler.Some().Val().(mKs.IBusHandlerSubscribe)
	sf.Unsubscribe(hand)
	return resp
}