package bootstrap

import (
	"context"
	"fmt"
	"time"

	"go.uber.org/zap"

	edgeevents "iop/apps/edge/internal/events"
	edgeinput "iop/apps/edge/internal/input"
	edgenode "iop/apps/edge/internal/node"
	edgeservice "iop/apps/edge/internal/service"
	"iop/apps/edge/internal/transport"
	"iop/packages/config"
	"iop/packages/observability"
)

// Runtime is the shared edge runtime assembly used by both `serve` and
// `console` entrypoints. NewRuntime wires logger, registry, node store,
// event bus, service, and transport server; Start performs handler wiring
// and binds the server and metrics endpoint.
type Runtime struct {
	Cfg       *config.EdgeConfig
	Logger    *zap.Logger
	Registry  *edgenode.Registry
	NodeStore *edgenode.NodeStore
	EventBus  *edgeevents.Bus
	Service   *edgeservice.Service
	Server    *transport.Server
	Input     *edgeinput.Manager
}

func NewRuntime(cfg *config.EdgeConfig) (*Runtime, error) {
	logger, err := observability.NewLogger(cfg.Logging.Level, cfg.Logging.Pretty)
	if err != nil {
		return nil, err
	}

	registry := edgenode.NewRegistry()
	nodeStore, err := edgenode.LoadFromConfig(cfg.Nodes)
	if err != nil {
		return nil, fmt.Errorf("edge: seed node store: %w", err)
	}

	bus := edgeevents.NewBus()
	svc := edgeservice.New(registry, bus)
	inputManager := edgeinput.NewManager(*cfg, svc, logger.Named("input"))

	server, err := transport.NewServer(cfg.Server.Listen, registry, nodeStore, logger)
	if err != nil {
		return nil, err
	}

	return &Runtime{
		Cfg:       cfg,
		Logger:    logger,
		Registry:  registry,
		NodeStore: nodeStore,
		EventBus:  bus,
		Service:   svc,
		Server:    server,
		Input:     inputManager,
	}, nil
}

func (r *Runtime) wireHandlers() {
	r.Server.SetRunEventHandler(r.EventBus.PublishRun)
	r.Server.SetNodeEventHandler(r.EventBus.PublishNode)
}

func (r *Runtime) Start(ctx context.Context) error {
	r.wireHandlers()
	if err := r.Server.Start(ctx); err != nil {
		return err
	}
	if err := r.Input.Start(ctx); err != nil {
		_ = r.Server.Stop()
		return err
	}
	go func() {
		if err := observability.ServeMetrics(r.Cfg.Metrics.Port); err != nil {
			r.Logger.Warn("metrics server exited", zap.Error(err))
		}
	}()
	return nil
}

func (r *Runtime) Stop() error {
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	inputErr := r.Input.Stop(ctx)
	err := r.Server.Stop()
	_ = r.Logger.Sync()
	if err == nil {
		err = inputErr
	}
	return err
}