package protoc_gen_kit

import (
	"context"
	"git.diulo.com/mogfee/protoc-gen-kit/log"
	"github.com/google/uuid"
	"golang.org/x/sync/errgroup"
	"os"
	"sync"
	"syscall"
	"time"
)

type AppInfo interface {
	ID() string
	Name() string
	Version() string
	Metadata() map[string]string
	Endpoint() []string
}
type App struct {
	opts     options
	ctx      context.Context
	cancel   func()
	mu       sync.Mutex
	instance *registry.ServiceInstance
}

func New(opts ...Option) *App {
	o := options{
		ctx:              context.Background(),
		sigs:             []os.Signal{syscall.SIGTERM, syscall.SIGQUIT, syscall.SIGINT},
		registrarTimeout: 10 * time.Second,
		stopTimeout:      10 * time.Second,
	}
	if id, err := uuid.NewUUID(); err == nil {
		o.id = id.String()
	}
	for _, opt := range opts {
		opt(&o)
	}
	if o.logger != nil {
		log.SetLogger(o.logger)
	}
	ctx, cancel := context.WithCancel(o.ctx)
	return &App{
		opts:   o,
		ctx:    ctx,
		cancel: cancel,
	}
}

// ID returns app instance id.
func (a *App) ID() string { return a.opts.id }

// Name returns service name.
func (a *App) Name() string { return a.opts.name }

// Version returns app version.
func (a *App) Version() string { return a.opts.version }

// Metadata returns service metadata.
func (a *App) Metadata() map[string]string { return a.opts.metadata }

// Endpoint returns endpoints.
func (a *App) Endpoint() []string {
	if a.instance != nil {
		return a.instance.Endpoints
	}
	return nil
}
func (a *App) Run() error {
	instance, err := a.buildInstance()
	if err != nil {
		return err
	}
	a.mu.Lock()
	a.instance = instance
	a.mu.Unlock()

	sctx := NewContext(a.ctx, a)
	eg, ctx := errgroup.WithContext(sctx)
	wg := sync.WaitGroup{}
	for _, fn := range a.opts.beforeStart {
		if err = fn(sctx); err != nil {
			return err
		}
	}
	for _, srv := range a.opts.servers {
		srv := srv
		eg.Go(func() error {
			<-ctx.Done()
			stopCtx, cancel := context.WithTimeout(NewContext(a.opts.ctx, a))
			defer cancel()
			return srv.Stop(stopCtx)
		})
		wg.Add(1)
		eg.Go(func() error {
			wg.Done()
			return srv.Start(sctx)
		})
	}
	wg.Wait()

}