move gotd fork into repo. (#111)

- update to latest telegram layer
- remove some references to fields in tg.Entities that don't exist in
the schema
- originally added here:
https://github.com/beeper/td/commit/820929062a2ba0104397bc01235ab58a9cff780e
  - referenced here
-
https://github.com/mautrix/telegramgo/commit/124f0967ed195b5a380c9bd02e170ada9710dde3
-
https://github.com/mautrix/telegramgo/commit/4205047aab2e0639217148b5d125bfaab668bd8e

pkg/gotd/telegram/conn_builder.go

@@ -0,0 +1,103 @@
+package telegram
+
+import (
+	"context"
+
+	"go.uber.org/zap"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/bin"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/mtproto"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/pool"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/dcs"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/internal/manager"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/tg"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/transport"
+)
+
+type clientHandler struct {
+	client *Client
+}
+
+func (c clientHandler) OnSession(cfg tg.Config, s mtproto.Session) (err error) {
+	err = c.client.onSession(cfg, s)
+	if c.client.opts.Handler != nil {
+		c.client.opts.Handler.OnSession(s)
+	}
+	return
+}
+
+func (c clientHandler) OnMessage(b *bin.Buffer) error {
+	return c.client.handleUpdates(b)
+}
+
+func (c *Client) asHandler() manager.Handler {
+	return clientHandler{
+		client: c,
+	}
+}
+
+type connConstructor func(
+	create mtproto.Dialer,
+	mode manager.ConnMode,
+	appID int,
+	opts mtproto.Options,
+	connOpts manager.ConnOptions,
+) pool.Conn
+
+func defaultConstructor() connConstructor {
+	return func(
+		create mtproto.Dialer,
+		mode manager.ConnMode,
+		appID int,
+		opts mtproto.Options,
+		connOpts manager.ConnOptions,
+	) pool.Conn {
+		return manager.CreateConn(create, mode, appID, opts, connOpts)
+	}
+}
+
+func (c *Client) dcList() dcs.List {
+	cfg := c.cfg.Load()
+	return dcs.List{
+		Options: cfg.DCOptions,
+		Domains: c.domains,
+		Test:    c.testDC,
+	}
+}
+
+func (c *Client) primaryDC(dc int) mtproto.Dialer {
+	return func(ctx context.Context) (transport.Conn, error) {
+		return c.resolver.Primary(ctx, dc, c.dcList())
+	}
+}
+
+func (c *Client) createPrimaryConn(setup manager.SetupCallback) pool.Conn {
+	return c.createConn(0, c.defaultMode, setup, c.onDead, c.onAuthError)
+}
+
+func (c *Client) createConn(
+	id int64,
+	mode manager.ConnMode,
+	setup manager.SetupCallback,
+	onDead func(),
+	onAuthError func(error),
+) pool.Conn {
+	opts, s := c.session.Options(c.opts)
+	opts.Logger = c.log.Named("conn").With(
+		zap.Int64("conn_id", id),
+		zap.Int("dc_id", s.DC),
+	)
+
+	return c.create(
+		c.primaryDC(s.DC), mode, c.appID,
+		opts, manager.ConnOptions{
+			DC:          s.DC,
+			Test:        c.testDC,
+			Device:      c.device,
+			Handler:     c.asHandler(),
+			Setup:       setup,
+			OnDead:      onDead,
+			OnAuthError: onAuthError,
+		},
+	)
+}