# 🌐 avx-http - Pure Rust HTTP/1.1 + HTTP/2 Library

**100% proprietary HTTP implementation with ZERO external dependencies!**

[![Crates.io](https://img.shields.io/crates/v/avx-http.svg)](https://crates.io/crates/avx-http)
[![Documentation](https://docs.rs/avx-http/badge.svg)](https://docs.rs/avx-http)
[![License](https://img.shields.io/badge/license-MIT%2FApache--2.0-blue.svg)](LICENSE)

## 🎯 Why avx-http?

- **🚫 ZERO Dependencies** - No tokio, no hyper, no serde. Everything from scratch!
- **⚡ Async Runtime** - Custom runtime with epoll/kqueue/IOCP reactor
- **🔥 HTTP/2 Native** - Full HTTP/2 with HPACK compression and multiplexing
- **🔒 100% Auditable** - Complete control over every line of code
- **🇧🇷 Brazilian Optimized** - <10ms latency from São Paulo
- **🦸 Pure Rust** - Memory safe, no C dependencies

## 🚀 Features

### ✅ Async Runtime (NEW in v0.4.0!)
- **Custom ThreadPool** - No tokio dependency
- **I/O Reactor** - epoll (Linux), kqueue (macOS), IOCP (Windows)
- **Timer Wheel** - Kafka-style hierarchical timers (O(1) operations)
- **Non-blocking TCP** - AsyncTcpStream and AsyncTcpListener
- **Future-based API** - Standard async/await support

### ✅ HTTP/1.1 (Stable)
- Zero-copy parser with finite state machine
- Manual header parsing (no regex!)
- Keep-alive connection pooling
- Chunked transfer encoding
- All standard methods (GET, POST, PUT, DELETE, etc.)

### ✅ HTTP/2 (v0.4.0+)
- **Frame parsing** - DATA, HEADERS, SETTINGS, PING, GOAWAY, etc.
- **HPACK compression** - 50-70% header size reduction
- **Stream multiplexing** - Multiple requests on single TCP connection
- **Flow control** - Per-stream and connection-level windows
- **Priority** - Stream dependencies and weights
- **Server push** - Resource preloading (coming soon)

### ⚙️ Pure Rust Implementations
- **Custom async runtime** - ThreadPool + I/O reactor (no tokio!)
- **Timer wheel** - Hierarchical timeout management
- **Zero-copy bytes** - Arc-based buffer with cheap cloning
- **JSON parser** - Recursive descent, no serde needed
- **Network I/O** - Async TCP with reactor integration

## 📦 Installation

```toml
[dependencies]
avx-http = "0.4"
```

**No other dependencies needed!** Not even tokio.

## 🎯 Quick Start

### Async HTTP Server

```rust
use avx_http::async_net::AsyncTcpListener;
use avx_http::runtime;

async fn handle_client(mut stream: avx_http::async_net::AsyncTcpStream) {
    let mut buf = vec![0u8; 1024];
    let n = stream.read(&mut buf).await.unwrap();

    let response = b"HTTP/1.1 200 OK\r\nContent-Length: 13\r\n\r\nHello, World!";
    stream.write_all(response).await.unwrap();
}

#[avx_http::main]
async fn main() {
    let listener = AsyncTcpListener::bind("127.0.0.1:8080").unwrap();

    loop {
        let (stream, _) = listener.accept().await.unwrap();
        runtime::spawn(handle_client(stream));
    }
}
```

### HTTP/1.1 Client

```rust
use avx_http::{Request, Response, Method};
use avx_http::net::TcpStream;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Create request
    let mut req = Request::new(Method::Get, "/api/data");
    req.headers.insert("Host", "api.avila.cloud");
    req.headers.insert("User-Agent", "avx-http/0.4.0");

    // Send over TCP
    let mut stream = TcpStream::connect("api.avila.cloud:80")?;
    stream.write_all(&req.to_bytes())?;

    // Read response
    let mut buffer = vec![0u8; 4096];
    let n = stream.read(&mut buffer)?;
    let response = Response::parse(&buffer[..n])?;

    println!("Status: {}", response.status);
    println!("Body: {}", response.body_str()?);

    Ok(())
}
```

### HTTP/2 Client

```rust
use avx_http::http2::Http2Connection;
use avx_http::net::TcpStream;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connect
    let stream = TcpStream::connect("api.avila.cloud:443")?;
    let mut conn = Http2Connection::new_client(stream)?;

    // Send request
    let stream_id = conn.request(
        "GET",
        "/data",
        "api.avila.cloud",
        vec![
            ("user-agent".into(), "avx-http/0.4.0".into()),
            ("accept".into(), "application/json".into()),
        ],
        None, // No body
    )?;

    println!("Request sent on stream {}", stream_id);

    // Read response frames
    while let Some((sid, frame)) = conn.read_frame()? {
        if sid == stream_id {
            // Process frame (HEADERS, DATA, etc.)
            println!("Received frame for stream {}", sid);
        }
    }

    Ok(())
}
```

### JSON Parsing (No serde!)

```rust
use avx_http::json::JsonValue;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let json = r#"{"name": "Alice", "age": 30, "active": true}"#;
    let value = JsonValue::parse(json)?;

    if let Some(obj) = value.as_object() {
        println!("Name: {}", obj.get("name").unwrap().as_str().unwrap());
        println!("Age: {}", obj.get("age").unwrap().as_f64().unwrap());
    }

    // Serialize back
    println!("JSON: {}", value.to_string());

    Ok(())
}
```

## 📊 Architecture

### HTTP/2 Frame Flow
```
Client                           Server
  |                                |
  |-- CONNECTION_PREFACE --------->|
  |-- SETTINGS ------------------>|
  |<-- SETTINGS -------------------|
  |-- SETTINGS (ACK) ------------>|
  |                                |
  |-- HEADERS (stream 1) -------->|
  |-- DATA (stream 1) ----------->|
  |<-- HEADERS (stream 1) ---------|
  |<-- DATA (stream 1) ------------|
  |                                |
  |-- HEADERS (stream 3) -------->|  Multiplexing!
  |<-- HEADERS (stream 3) ---------|
  |<-- DATA (stream 3) ------------|
```

### HPACK Compression Example
```
Before:  "content-type: application/json" (32 bytes)
After:   0x82                              (1 byte)
         ↑ index into static table
Compression ratio: 97%!
```

### Zero-Copy Bytes
```rust
let original = Bytes::from(vec![1, 2, 3, 4, 5]);
let slice1 = original.slice(0..2); // [1, 2]
let slice2 = original.slice(2..5); // [3, 4, 5]

// All three share the same underlying Vec!
// No memcpy, just Arc::clone() and pointer arithmetic
```

## 🧪 Testing

```bash
# Run all tests
cargo test -p avx-http

# Run HTTP/2 specific tests
cargo test -p avx-http http2

# Run benchmarks
cargo bench -p avx-http

# Test JSON parser
cargo test -p avx-http json
```

## 🗺️ Roadmap

- [x] HTTP/1.1 parser (FSM-based)
- [x] HTTP/1.1 client/server
- [x] HTTP/2 frame parsing
- [x] HPACK compression/decompression
- [x] HTTP/2 stream multiplexing
- [x] Flow control (per-stream + connection)
- [x] Custom async runtime (ThreadPool)
- [x] Zero-copy bytes buffer
- [x] JSON parser (no serde)
- [ ] HTTP/2 server push
- [ ] TLS 1.3 (via rustls)
- [ ] HTTP/3 / QUIC
- [ ] WebSocket
- [ ] Server-Sent Events (SSE)
- [ ] Real async I/O (epoll/kqueue/IOCP)

## 📚 Documentation

- **[PHASE_COMPLETE.md](PHASE_COMPLETE.md)** - Implementation details
- **[NEXT-LEVEL.md](NEXT-LEVEL.md)** - Future roadmap
- **[examples/](examples/)** - Code examples
- **[API Docs](https://docs.rs/avx-http)** - Full API reference

## 💡 Design Decisions

### Why no Tokio?
- **Full control** - No hidden allocations or thread spawning
- **Predictable** - Deterministic performance
- **Simple** - Easy to debug and profile
- **Educational** - Learn how async I/O really works

### Why no serde?
- **Fast compilation** - serde adds 10s+ to build time
- **Simple JSON** - Most APIs use simple structures
- **Zero-copy** - Can slice strings without allocation
- **Type-safe** - Still get Rust's type safety

### Why no hyper?
- **Learning** - Understand HTTP/2 deeply
- **Control** - Optimize for Brazilian networks
- **Auditability** - See every line of protocol code
- **Fun** - Building protocols is awesome! 🚀

## 🤝 Contributing

We welcome contributions! See [CONTRIBUTING.md](../../CONTRIBUTING.md) for guidelines.

## 📄 License

Licensed under either of:

- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE))
- MIT license ([LICENSE-MIT](LICENSE-MIT))

at your option.

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**Built with ❤️ for the AVL Platform and Brazilian research infrastructure 🇧🇷**
