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/message/file_promise.go

@@ -0,0 +1,123 @@
+package message
+
+import (
+	"context"
+	"io"
+	"io/fs"
+
+	"go.uber.org/atomic"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/uploader"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/uploader/source"
+	"go.mau.fi/mautrix-telegram/pkg/gotd/tg"
+)
+
+// Uploader is an abstraction for Telegram file uploader.
+type Uploader interface {
+	FromFile(ctx context.Context, f uploader.File, name string) (tg.InputFileClass, error)
+	FromPath(ctx context.Context, path, name string) (tg.InputFileClass, error)
+	FromFS(ctx context.Context, filesystem fs.FS, path, name string) (tg.InputFileClass, error)
+	FromReader(ctx context.Context, name string, f io.Reader) (tg.InputFileClass, error)
+	FromBytes(ctx context.Context, name string, b []byte) (tg.InputFileClass, error)
+	FromURL(ctx context.Context, rawURL string) (tg.InputFileClass, error)
+	FromSource(ctx context.Context, src source.Source, rawURL string) (tg.InputFileClass, error)
+}
+
+type uploadBuilder struct {
+	upload Uploader
+}
+
+// UploadOption is a UploadBuilder creation option.
+type UploadOption interface {
+	apply(ctx context.Context, b uploadBuilder) (tg.InputFileClass, error)
+}
+
+// uploadOptionFunc is a functional adapter for UploadOption.
+type uploadOptionFunc func(ctx context.Context, b uploadBuilder) (tg.InputFileClass, error)
+
+func (f uploadOptionFunc) apply(ctx context.Context, b uploadBuilder) (tg.InputFileClass, error) {
+	return f(ctx, b)
+}
+
+type fileCache atomic.Value
+
+func (r *fileCache) Store(result tg.InputFileClass) {
+	r.Value.Store(result)
+}
+
+func (r *fileCache) Load() (result tg.InputFileClass, ok bool) {
+	result, ok = r.Value.Load().(tg.InputFileClass)
+	return
+}
+
+// FilePromise is a upload file promise.
+type FilePromise = func(ctx context.Context, b Uploader) (tg.InputFileClass, error)
+
+// Upload creates new upload options using given promise.
+func Upload(promise FilePromise) UploadOption {
+	once := &fileCache{}
+	return uploadOptionFunc(func(ctx context.Context, b uploadBuilder) (r tg.InputFileClass, err error) {
+		if v, ok := once.Load(); ok {
+			return v, nil
+		}
+		defer func() {
+			if err == nil && r != nil {
+				once.Store(r)
+			}
+		}()
+
+		return promise(ctx, b.upload)
+	})
+}
+
+// FromFile uploads given File.
+// NB: FromFile does not close given file.
+func FromFile(f uploader.File) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromFile(ctx, f, "")
+	})
+}
+
+// FromPath uploads file from given path.
+func FromPath(path, name string) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromPath(ctx, path, name)
+	})
+}
+
+// FromFS uploads file from given path using given fs.FS.
+func FromFS(filesystem fs.FS, path, name string) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromFS(ctx, filesystem, path, name)
+	})
+}
+
+// FromReader uploads file from given io.Reader.
+// NB: totally stream should not exceed the limit for
+// small files (10 MB as docs says, may be a bit bigger).
+func FromReader(name string, r io.Reader) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromReader(ctx, name, r)
+	})
+}
+
+// FromBytes uploads file from given byte slice.
+func FromBytes(name string, data []byte) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromBytes(ctx, name, data)
+	})
+}
+
+// FromURL uploads file from given URL.
+func FromURL(rawURL string) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromURL(ctx, rawURL)
+	})
+}
+
+// FromSource uploads file from given URL using given Source.
+func FromSource(src source.Source, rawURL string) UploadOption {
+	return Upload(func(ctx context.Context, b Uploader) (tg.InputFileClass, error) {
+		return b.FromSource(ctx, src, rawURL)
+	})
+}