package app

import (
	"errors"
	"sync"

	"github.com/rs/zerolog"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/codes"

	"gitea.libretechconsulting.com/rmcguire/go-app/pkg/config"
)

func (a *App) Done() <-chan any {
	return a.appDone
}

func (a *App) MustRun() {
	if a.cfg != nil {
		panic(errors.New("already ran app trying to run"))
	}

	// Set up app
	a.cfg = config.MustFromCtx(a.AppContext)
	a.l = zerolog.Ctx(a.AppContext)
	a.shutdownFuncs = make([]shutdownFunc, 0)
	a.appDone = make(chan any)
	a.HTTP.HTTPDone = make(chan any)

	if !a.cfg.HTTPEnabled() && !a.cfg.GRPCEnabled() {
		panic(errors.New("neither http nor grpc enabled, nothing to do"))
	}

	if len(a.HTTP.Funcs) < 1 {
		a.l.Warn().Msg("no http funcs provided, only serving health and metrics")
	}

	// Start OTEL
	// Registers a NO-OP provider if not enabled
	a.initOTEL()

	ctx, initSpan := a.tracer.Start(a.AppContext, "init")
	defer initSpan.End()

	var serverWG sync.WaitGroup

	// Start HTTP (does not block)
	if a.cfg.HTTPEnabled() {
		serverWG.Add(1)
		go func() {
			defer serverWG.Done()
			if err := a.initHTTP(ctx); err != nil {
				initSpan.RecordError(err)
				initSpan.SetStatus(codes.Error, err.Error())
			}
			initSpan.AddEvent("http server started")
			initSpan.SetAttributes(attribute.Int("http.handlers", len(a.HTTP.Funcs)))
		}()
	}

	// Start GRPC (does not block)
	if a.cfg.GRPCEnabled() {
		serverWG.Add(1)
		go func() {
			defer serverWG.Done()
			if err := a.initGRPC(ctx); err != nil {
				initSpan.RecordError(err)
				initSpan.SetStatus(codes.Error, err.Error())
			}
			initSpan.AddEvent("grpc server started")
			initSpan.SetAttributes(attribute.Int("grpc.services", len(a.GRPC.Services)))
		}()
	}

	serverWG.Wait()

	// Monitor app lifecycle
	go a.run()

	// Startup Complete
	a.l.Info().
		Str("name", a.cfg.Name).
		Str("version", a.cfg.Version).
		Str("logLevel", a.cfg.Logging.Level).
		Msg("app initialized")
	initSpan.SetStatus(codes.Ok, "")
}