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// Copyright 2021-2024 Buf Technologies, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import { create } from "./create.js";
import { readField } from "./from-binary.js";
import { reflect } from "./reflect/reflect.js";
import { scalarZeroValue } from "./reflect/scalar.js";
import { writeField } from "./to-binary.js";
import { BinaryReader, BinaryWriter } from "./wire/binary-encoding.js";
import { isWrapperDesc } from "./wkt/wrappers.js";
/**
* Retrieve an extension value from a message.
*
* The function never returns undefined. Use hasExtension() to check whether an
* extension is set. If the extension is not set, this function returns the
* default value (if one was specified in the protobuf source), or the zero value
* (for example `0` for numeric types, `[]` for repeated extension fields, and
* an empty message instance for message fields).
*
* Extensions are stored as unknown fields on a message. To mutate an extension
* value, make sure to store the new value with setExtension() after mutating.
*
* If the extension does not extend the given message, an error is raised.
*/
export function getExtension(message, extension) {
assertExtendee(extension, message);
const ufs = filterUnknownFields(message.$unknown, extension);
const [container, field, get] = createExtensionContainer(extension);
for (const uf of ufs) {
readField(container, new BinaryReader(uf.data), field, uf.wireType, {
readUnknownFields: false,
});
}
return get();
}
/**
* Set an extension value on a message. If the message already has a value for
* this extension, the value is replaced.
*
* If the extension does not extend the given message, an error is raised.
*/
export function setExtension(message, extension, value) {
var _a;
assertExtendee(extension, message);
const ufs = ((_a = message.$unknown) !== null && _a !== void 0 ? _a : []).filter((uf) => uf.no !== extension.number);
const [container, field] = createExtensionContainer(extension, value);
const writer = new BinaryWriter();
writeField(writer, { writeUnknownFields: false }, container, field);
const reader = new BinaryReader(writer.finish());
while (reader.pos < reader.len) {
const [no, wireType] = reader.tag();
const data = reader.skip(wireType, no);
ufs.push({ no, wireType, data });
}
message.$unknown = ufs;
}
/**
* Remove an extension value from a message.
*
* If the extension does not extend the given message, an error is raised.
*/
export function clearExtension(message, extension) {
assertExtendee(extension, message);
if (message.$unknown === undefined) {
return;
}
message.$unknown = message.$unknown.filter((uf) => uf.no !== extension.number);
}
/**
* Check whether an extension is set on a message.
*/
export function hasExtension(message, extension) {
var _a;
return (extension.extendee.typeName === message.$typeName &&
!!((_a = message.$unknown) === null || _a === void 0 ? void 0 : _a.find((uf) => uf.no === extension.number)));
}
/**
* Check whether an option is set on a descriptor.
*
* Options are extensions to the `google.protobuf.*Options` messages defined in
* google/protobuf/descriptor.proto. This function gets the option message from
* the descriptor, and calls hasExtension().
*/
export function hasOption(element, option) {
const message = element.proto.options;
if (!message) {
return false;
}
return hasExtension(message, option);
}
/**
* Retrieve an option value from a descriptor.
*
* Options are extensions to the `google.protobuf.*Options` messages defined in
* google/protobuf/descriptor.proto. This function gets the option message from
* the descriptor, and calls getExtension(). Same as getExtension(), this
* function never returns undefined.
*/
export function getOption(element, option) {
const message = element.proto.options;
if (!message) {
const [, , get] = createExtensionContainer(option);
return get();
}
return getExtension(message, option);
}
function filterUnknownFields(unknownFields, extension) {
if (unknownFields === undefined)
return [];
if (extension.fieldKind === "enum" || extension.fieldKind === "scalar") {
// singular scalar fields do not merge, we pick the last
for (let i = unknownFields.length - 1; i >= 0; --i) {
if (unknownFields[i].no == extension.number) {
return [unknownFields[i]];
}
}
return [];
}
return unknownFields.filter((uf) => uf.no === extension.number);
}
/**
* @private
*/
export function createExtensionContainer(extension, value) {
const localName = extension.typeName;
const field = Object.assign(Object.assign({}, extension), { kind: "field", parent: extension.extendee, localName });
const desc = Object.assign(Object.assign({}, extension.extendee), { fields: [field], members: [field], oneofs: [] });
const container = create(desc, value !== undefined ? { [localName]: value } : undefined);
return [
reflect(desc, container),
field,
() => {
const value = container[localName];
if (value === undefined) {
// Only message fields are undefined, rest will have a zero value.
const desc = extension.message;
if (isWrapperDesc(desc)) {
return scalarZeroValue(desc.fields[0].scalar, desc.fields[0].longAsString);
}
return create(desc);
}
return value;
},
];
}
function assertExtendee(extension, message) {
if (extension.extendee.typeName != message.$typeName) {
throw new Error(`extension ${extension.typeName} can only be applied to message ${extension.extendee.typeName}`);
}
}