Add ProtobufMessage support (#137)

* Update ProtobufMessage

* Update ProtobufEncoder and ProtobufDecoder

* Fix warning issue

Author: Kyle-Ye

Sources/OpenSwiftUICore/Data/Protobuf/ProtobufDecoder.swift

@@ -0,0 +1,39 @@
+//
+//  ProtobufDecoder.swift
+//  OpenSwiftUICore
+//
+//  Audited for RELEASE_2024
+//  Status: WIP
+
+import Foundation
+
+package struct ProtobufDecoder {
+    package enum DecodingError: Error {
+        case failed
+    }
+    
+    package typealias Field = ProtobufFormat.Field
+    package typealias WireType = ProtobufFormat.WireType
+    
+    
+    var data: NSData
+    var ptr: UnsafeRawPointer
+    var end: UnsafeRawPointer
+    var packedField: Field = Field(rawValue: 0)
+    var packedEnd: UnsafeRawPointer
+    var stack: [UnsafeRawPointer] = []
+    package var userInfo: [CodingUserInfoKey : Any] = [:]
+    
+    package init(_ data: Data) {
+        let nsData = data as NSData
+        self.data = nsData
+        let ptr = nsData.bytes
+        self.ptr = ptr
+        self.end = ptr + nsData.length
+        self.packedEnd = ptr
+    }
+}
+
+extension ProtobufDecoder {
+    // TODO: Implement decoding methods
+}

Sources/OpenSwiftUICore/Data/Protobuf/ProtobufEncoder.swift

@@ -0,0 +1,44 @@
+//
+//  ProtobufEncoder.swift
+//  OpenSwiftUICore
+//
+//  Audited for RELEASE_2024
+//  Status: WIP
+//  ID: C7B3AAD101AF9EA76FC322BD6EF713E6
+
+import Foundation
+
+package struct ProtobufEncoder {
+    package enum EncodingError: Error {
+        case failed
+    }
+    package typealias Field = ProtobufFormat.Field
+    package typealias WireType = ProtobufFormat.WireType
+    
+    var buffer: UnsafeMutableRawPointer = .init(bitPattern: 0)!
+    var size: Int = 0
+    var capacity: Int = 0
+    var stack: [Int] = []
+    package var userInfo: [CodingUserInfoKey: Any] = [:]
+    
+    package static func encoding(_ body: (inout ProtobufEncoder) throws -> Void) rethrows -> Data {
+        var encoder = ProtobufEncoder()
+        try body(&encoder)
+        defer { free(encoder.buffer) }
+        return encoder.takeData()
+    }
+    
+    package static func encoding<T>(_ value: T) throws -> Data where T: ProtobufEncodableMessage {
+        try encoding { encoder in
+            try value.encode(to: &encoder)
+        }
+    }
+    
+    private func takeData() -> Data {
+        Data(bytes: buffer, count: size)
+    }
+}
+
+extension ProtobufEncoder {
+    // TODO: Implement encoding methods
+}

Sources/OpenSwiftUICore/Data/Protobuf/ProtobufMessage.swift

@@ -0,0 +1,141 @@
+//
+//  ProtobufMessage.swift
+//  OpenSwiftUICore
+//
+//  Audited for RELEASE_2024
+//  Status: Complete
+
+import Foundation
+
+// MARK: - ProtobufMessage
+
+package protocol ProtobufEncodableMessage {
+    func encode(to encoder: inout ProtobufEncoder) throws
+}
+package protocol ProtobufDecodableMessage {
+    init(from decoder: inout ProtobufDecoder) throws
+}
+
+package typealias ProtobufMessage = ProtobufDecodableMessage & ProtobufEncodableMessage
+
+// MARK: - ProtobufEnum
+
+package protocol ProtobufEnum {
+    var protobufValue: UInt { get }
+    init?(protobufValue: UInt)
+}
+
+extension ProtobufEnum where Self: RawRepresentable, RawValue: BinaryInteger {
+    package var protobufValue: UInt {
+        UInt(rawValue)
+    }
+    
+    package init?(protobufValue: UInt) {
+        self.init(rawValue: RawValue(protobufValue))
+    }
+}
+
+// MARK: - ProtobufTag
+
+package protocol ProtobufTag: Equatable {
+    var rawValue: UInt { get }
+    init(rawValue: UInt)
+}
+
+// MARK: - ProtobufFormat
+
+package enum ProtobufFormat {
+    package struct WireType: Equatable {
+        package let rawValue: UInt
+        package init(rawValue: UInt) {
+            self.rawValue = rawValue
+        }
+        
+        package static var varint: ProtobufFormat.WireType { WireType(rawValue: 0) }
+        package static var fixed64: ProtobufFormat.WireType { WireType(rawValue: 1) }
+        package static var lengthDelimited: ProtobufFormat.WireType { WireType(rawValue: 2) }
+        package static var fixed32: ProtobufFormat.WireType { WireType(rawValue: 5) }
+    }
+    
+    package struct Field: Equatable {
+        package var rawValue: UInt
+        package init(rawValue: UInt) {
+            self.rawValue = rawValue
+        }
+        
+        // field = (field_number << 3) | wire_type
+        // See https://protobuf.dev/programming-guides/encoding/
+        package init(_ tag: UInt, wireType: WireType) {
+            rawValue = (tag << 3) | wireType.rawValue
+        }
+        
+        package var tag: UInt {
+            rawValue >> 3
+        }
+        
+        package var wireType: WireType {
+            WireType(rawValue: rawValue & 7)
+        }
+        
+        @inline(__always)
+        package func tag<T>(as: T.Type = T.self) -> T where T: ProtobufTag {
+            T(rawValue: tag)
+        }
+    }
+}
+
+// MARK: - CoddleByProtobuf
+
+package protocol CodaleByProtobuf: Codable, ProtobufMessage {}
+
+extension CodaleByProtobuf {
+    func encode(to encoder: any Encoder) throws {
+        let data = try ProtobufEncoder.encoding { protobufEncoder in
+            protobufEncoder.userInfo = encoder.userInfo
+            try encode(to: &protobufEncoder)
+        }
+        var container = encoder.singleValueContainer()
+        try container.encode(data)
+    }
+    
+    init(from decoder: any Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        let data = try container.decode(Data.self)
+        var protobufDecoder = ProtobufDecoder(data)
+        protobufDecoder.userInfo = decoder.userInfo
+        self = try Self(from: &protobufDecoder)
+    }
+}
+
+// MARK: - ProtobufCodable
+
+@propertyWrapper
+package struct ProtobufCodable<Value>: Swift.Codable where Value: ProtobufMessage {
+    package var wrappedValue: Value
+    package init(wrappedValue: Value) {
+        self.wrappedValue = wrappedValue
+    }
+
+    package func encode(to encoder: any Encoder) throws {
+        let data = try ProtobufEncoder.encoding { protobufEncoder in
+            protobufEncoder.userInfo = encoder.userInfo
+            try wrappedValue.encode(to: &protobufEncoder)
+        }
+        var container = encoder.singleValueContainer()
+        try container.encode(data)
+    }
+
+    package init(from decoder: any Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        let data = try container.decode(Data.self)
+        var protobufDecoder = ProtobufDecoder(data)
+        protobufDecoder.userInfo = decoder.userInfo
+        wrappedValue = try Value(from: &protobufDecoder)
+    }
+}
+
+extension ProtobufCodable: Equatable where Value: Equatable {
+    package static func == (lhs: ProtobufCodable<Value>, rhs: ProtobufCodable<Value>) -> Bool {
+        lhs.wrappedValue == rhs.wrappedValue
+    }
+}