package watermark

import (
	"database/sql"

	"github.com/ThreeDotsLabs/watermill"
	watersql "github.com/ThreeDotsLabs/watermill-sql/v2/pkg/sql"
	"github.com/ThreeDotsLabs/watermill/components/cqrs"
	"github.com/ThreeDotsLabs/watermill/message"
	"github.com/go-kratos/kratos/v2/log"
)

type CQRSBus struct {
	CommandBus *cqrs.CommandBus
	EventBus   *cqrs.EventBus
	Router     *message.Router
}

func NewCQRSBus(db *sql.DB, logger log.Logger) (*CQRSBus, error) {
	helper := log.NewHelper(logger)
	wmLogger := watermill.NewStdLogger(false, false)

	publisher, err := watersql.NewPublisher(db, watersql.PublisherConfig{
		SchemaAdapter:        watersql.DefaultPostgreSQLSchema{},
		AutoInitializeSchema: true,
	}, wmLogger)
	if err != nil {
		return nil, err
	}

	subscriber, err := watersql.NewSubscriber(db, watersql.SubscriberConfig{
		SchemaAdapter:    watersql.DefaultPostgreSQLSchema{},
		OffsetsAdapter:   watersql.DefaultPostgreSQLOffsetsAdapter{},
		InitializeSchema: true,
	}, wmLogger)
	if err != nil {
		return nil, err
	}

	// subscriber will be used later to wire event handlers on the router
	_ = subscriber

	router, err := message.NewRouter(message.RouterConfig{}, wmLogger)
	if err != nil {
		return nil, err
	}

	cqrsMarshaler := cqrs.JSONMarshaler{}

	commandBus, err := cqrs.NewCommandBusWithConfig(publisher, cqrs.CommandBusConfig{
		GeneratePublishTopic: func(params cqrs.CommandBusGeneratePublishTopicParams) (string, error) {
			return "commands." + params.CommandName, nil
		},
		Marshaler: cqrsMarshaler,
		Logger:    wmLogger,
	})
	if err != nil {
		return nil, err
	}

	eventBus, err := cqrs.NewEventBusWithConfig(publisher, cqrs.EventBusConfig{
		GeneratePublishTopic: func(params cqrs.GenerateEventPublishTopicParams) (string, error) {
			return "events." + params.EventName, nil
		},
		Marshaler: cqrsMarshaler,
		Logger:    wmLogger,
	})
	if err != nil {
		return nil, err
	}

	helper.Info("Watermill CQRS bus initialized with PostgreSQL")
	return &CQRSBus{
		CommandBus: commandBus,
		EventBus:   eventBus,
		Router:     router,
	}, nil
}