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/query/internal/itergen/method.go

@@ -0,0 +1,100 @@
+package main
+
+import (
+	"go/types"
+	"sort"
+	"strings"
+
+	"go.mau.fi/mautrix-telegram/pkg/gotd/telegram/query/internal/genutil"
+)
+
+// Param represents request parameter.
+type Param struct {
+	// Name to use in function declaration.
+	Name string
+	// OriginalName in struct definition.
+	OriginalName string
+	// Go type.
+	Type string
+}
+
+func varToParam(field *types.Var) Param {
+	fieldName := field.Name()
+	fieldName = strings.ToLower(fieldName[:1]) + fieldName[1:]
+	return Param{
+		Name:         fieldName,
+		OriginalName: field.Name(),
+		Type:         genutil.PrintType(field.Type()),
+	}
+}
+
+func sortParams(p []Param) []Param {
+	sort.SliceStable(p, func(i, j int) bool {
+		return p[i].Name < p[j].Name
+	})
+
+	return p
+}
+
+// SpecialCaseChain represents special request parameter setter.
+type SpecialCaseChain struct {
+	// ConstructorName to use in function body.
+	ConstructorName string
+	// ConstructorType to use in function body.
+	ConstructorType string
+	// Field of request struct.
+	Field Param
+	// Args is a slice of arguments. May be empty.
+	Args []Param
+}
+
+// RequestArgument represents request parameter passed by iterator.
+type RequestArgument struct {
+	// Arg describes argument.
+	Arg Param
+	// Chain is flag to generate builder chain setter.
+	Chain bool
+	// RequiredByIter is flag to generate pass to iterator constructor.
+	RequiredByIter bool
+}
+
+// Method is a RPC method.
+type Method struct {
+	// Name to use in function declaration.
+	Name string
+	// OriginalName is name of method of tg.Client.
+	OriginalName string
+	// RequestName is name of request struct.
+	RequestName string
+	// ResultName is name of result type.
+	ResultName string
+	// RequiredParams is a required params for query builder.
+	RequiredParams []Param
+	// AdditionalMapping is names of field from iterator.
+	// Some type doesn't have AddOffset for example, so we customize mapping here.
+	AdditionalMapping []RequestArgument
+
+	// SpecialCase is a slice of special case chains.
+	// Like tg.MessagesFilterClass constructor field setters.
+	SpecialCase []SpecialCaseChain
+
+	// Other parameters of request to pass it in constructor.
+	AdditionalParams []Param
+
+	// IteratorName is name of iterator to build.
+	IteratorName string
+	// ElemName  is name of iterator elem.
+	ElemName string
+}
+
+// Config is codegeneration config to use.
+type Config struct {
+	// Methods to generate helpers and query builders.
+	Methods []Method
+	// ResultName package name
+	Package string
+	// ResultName is name of result type.
+	ResultName string
+	// RequestFields is a slice of request struct fields.
+	RequestFields []Param
+}