package centrifugo

import (
	"context"
	"encoding/json"
	"net/http"

	"git.golem15.com/golem15/summercms/modules/backpack"
	"git.golem15.com/golem15/summercms/modules/lighthouse"
)

// DriverName is the realtime.driver value of this driver.
const DriverName = "centrifugo"

func init() {
	lighthouse.RegisterDriver(DriverName, func(app *backpack.App, svc *lighthouse.Service) (lighthouse.Driver, error) {
		var cfg Config
		if app != nil {
			cfg = LoadConfig(app.Config)
		} else {
			cfg = LoadConfig(nil)
		}
		return NewDriver(svc, cfg, nil), nil
	})
}

// Driver is the Centrifugo lighthouse.Driver: it publishes through Client
// and declares the token route (UserAuth) and the subscribe proxy route
// (ServerToServer).
type Driver struct {
	svc    *lighthouse.Service
	cfg    Config
	client *Client
	issuer *TokenIssuer
}

// NewDriver builds the driver for svc from cfg. hc may be nil (see
// NewClient).
func NewDriver(svc *lighthouse.Service, cfg Config, hc *http.Client) *Driver {
	c := NewClient(cfg, hc)
	c.log = svc.Logger()
	return &Driver{
		svc:    svc,
		cfg:    cfg,
		client: c,
		issuer: NewTokenIssuer(cfg.TokenSecret, cfg.TokenTTL),
	}
}

// Name returns "centrifugo".
func (d *Driver) Name() string { return DriverName }

// Config returns the driver's configuration.
func (d *Driver) Config() Config { return d.cfg }

// Client returns the HTTP API client.
func (d *Driver) Client() *Client { return d.client }

// Issuer returns the token issuer.
func (d *Driver) Issuer() *TokenIssuer { return d.issuer }

// Publish sends event to one channel through Client.Publish.
func (d *Driver) Publish(ctx context.Context, channel, event string, payload json.RawMessage) error {
	return d.client.Publish(ctx, channel, event, payload)
}

// Broadcast sends event to several channels through Client.Broadcast.
func (d *Driver) Broadcast(ctx context.Context, channels []string, event string, payload json.RawMessage) error {
	return d.client.Broadcast(ctx, channels, event, payload)
}

// Routes returns GET token_path (UserAuth, TokenHandler) and POST
// subscribe_path (ServerToServer, ProxyHandler).
func (d *Driver) Routes() []lighthouse.Route {
	return []lighthouse.Route{
		{Name: "token", Method: http.MethodGet, Path: d.cfg.TokenPath, Surface: lighthouse.UserAuth, Handler: TokenHandler(d.svc, d.issuer)},
		{Name: "subscribe", Method: http.MethodPost, Path: d.cfg.SubscribePath, Surface: lighthouse.ServerToServer, Handler: ProxyHandler(d.svc, d.cfg)},
	}
}