Added accurate MTProto Frame Types + Tokio Async Intergr

src/stream/frame.rs

@@ -0,0 +1,187 @@
+//! MTProto frame types and traits
+//!
+//! This module defines the common types and traits used by all
+//! frame encoding/decoding implementations.
+
+use bytes::{Bytes, BytesMut};
+use std::io::Result;
+
+use crate::protocol::constants::ProtoTag;
+
+// ============= Frame Types =============
+
+/// A decoded MTProto frame
+#[derive(Debug, Clone)]
+pub struct Frame {
+    /// Frame payload data
+    pub data: Bytes,
+    /// Frame metadata
+    pub meta: FrameMeta,
+}
+
+impl Frame {
+    /// Create a new frame with data and default metadata
+    pub fn new(data: Bytes) -> Self {
+        Self {
+            data,
+            meta: FrameMeta::default(),
+        }
+    }
+    
+    /// Create a new frame with data and metadata
+    pub fn with_meta(data: Bytes, meta: FrameMeta) -> Self {
+        Self { data, meta }
+    }
+    
+    /// Create an empty frame
+    pub fn empty() -> Self {
+        Self::new(Bytes::new())
+    }
+    
+    /// Check if frame is empty
+    pub fn is_empty(&self) -> bool {
+        self.data.is_empty()
+    }
+    
+    /// Get frame length
+    pub fn len(&self) -> usize {
+        self.data.len()
+    }
+    
+    /// Create a QuickAck request frame
+    pub fn quickack(data: Bytes) -> Self {
+        Self {
+            data,
+            meta: FrameMeta {
+                quickack: true,
+                ..Default::default()
+            },
+        }
+    }
+    
+    /// Create a simple ACK frame
+    pub fn simple_ack(data: Bytes) -> Self {
+        Self {
+            data,
+            meta: FrameMeta {
+                simple_ack: true,
+                ..Default::default()
+            },
+        }
+    }
+}
+
+/// Frame metadata
+#[derive(Debug, Clone, Default)]
+pub struct FrameMeta {
+    /// Quick ACK requested - client wants immediate acknowledgment
+    pub quickack: bool,
+    /// This is a simple ACK message (reversed data)
+    pub simple_ack: bool,
+    /// Original padding length (for secure mode)
+    pub padding_len: u8,
+}
+
+impl FrameMeta {
+    /// Create new empty metadata
+    pub fn new() -> Self {
+        Self::default()
+    }
+    
+    /// Create with quickack flag
+    pub fn with_quickack(mut self) -> Self {
+        self.quickack = true;
+        self
+    }
+    
+    /// Create with simple_ack flag
+    pub fn with_simple_ack(mut self) -> Self {
+        self.simple_ack = true;
+        self
+    }
+    
+    /// Create with padding length
+    pub fn with_padding(mut self, len: u8) -> Self {
+        self.padding_len = len;
+        self
+    }
+    
+    /// Check if any special flags are set
+    pub fn has_flags(&self) -> bool {
+        self.quickack || self.simple_ack
+    }
+}
+
+// ============= Codec Trait =============
+
+/// Trait for frame codecs that can encode and decode frames
+pub trait FrameCodec: Send + Sync {
+    /// Get the protocol tag for this codec
+    fn proto_tag(&self) -> ProtoTag;
+    
+    /// Encode a frame into the destination buffer
+    ///
+    /// Returns the number of bytes written.
+    fn encode(&self, frame: &Frame, dst: &mut BytesMut) -> Result<usize>;
+    
+    /// Try to decode a frame from the source buffer
+    ///
+    /// Returns:
+    /// - `Ok(Some(frame))` if a complete frame was decoded
+    /// - `Ok(None)` if more data is needed
+    /// - `Err(e)` if an error occurred
+    ///
+    /// On success, the consumed bytes are removed from `src`.
+    fn decode(&self, src: &mut BytesMut) -> Result<Option<Frame>>;
+    
+    /// Get the minimum bytes needed to determine frame length
+    fn min_header_size(&self) -> usize;
+    
+    /// Get the maximum allowed frame size
+    fn max_frame_size(&self) -> usize {
+        // Default: 16MB
+        16 * 1024 * 1024
+    }
+}
+
+// ============= Codec Factory =============
+
+/// Create a frame codec for the given protocol tag
+pub fn create_codec(proto_tag: ProtoTag) -> Box<dyn FrameCodec> {
+    match proto_tag {
+        ProtoTag::Abridged => Box::new(super::frame_codec::AbridgedCodec::new()),
+        ProtoTag::Intermediate => Box::new(super::frame_codec::IntermediateCodec::new()),
+        ProtoTag::Secure => Box::new(super::frame_codec::SecureCodec::new()),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    
+    #[test]
+    fn test_frame_creation() {
+        let frame = Frame::new(Bytes::from_static(b"test"));
+        assert_eq!(frame.len(), 4);
+        assert!(!frame.is_empty());
+        assert!(!frame.meta.quickack);
+        
+        let frame = Frame::empty();
+        assert!(frame.is_empty());
+        
+        let frame = Frame::quickack(Bytes::from_static(b"ack"));
+        assert!(frame.meta.quickack);
+    }
+    
+    #[test]
+    fn test_frame_meta() {
+        let meta = FrameMeta::new()
+            .with_quickack()
+            .with_padding(3);
+        
+        assert!(meta.quickack);
+        assert!(!meta.simple_ack);
+        assert_eq!(meta.padding_len, 3);
+        assert!(meta.has_flags());
+    }
+}