use super::*;
use bytes::{Buf, BufMut, Bytes, BytesMut};
fn len(puback: &PubAck, properties: &Option<PubAckProperties>) -> usize {
let mut len = 2 + 1;
if puback.reason == PubAckReason::Success && properties.is_none() {
return 2;
}
if let Some(p) = properties {
let properties_len = properties::len(p);
let properties_len_len = len_len(properties_len);
len += properties_len_len + properties_len;
} else {
len += 1;
}
len
}
pub fn read(
fixed_header: FixedHeader,
mut bytes: Bytes,
) -> Result<(PubAck, Option<PubAckProperties>), Error> {
let variable_header_index = fixed_header.fixed_header_len;
bytes.advance(variable_header_index);
let pkid = read_u16(&mut bytes)?;
if fixed_header.remaining_len == 2 {
return Ok((
PubAck {
pkid,
reason: PubAckReason::Success,
},
None,
));
}
let ack_reason = read_u8(&mut bytes)?;
if fixed_header.remaining_len < 4 {
return Ok((
PubAck {
pkid,
reason: reason(ack_reason)?,
},
None,
));
}
let puback = PubAck {
pkid,
reason: reason(ack_reason)?,
};
let properties = properties::read(&mut bytes)?;
Ok((puback, properties))
}
pub fn write(
puback: &PubAck,
properties: &Option<PubAckProperties>,
buffer: &mut BytesMut,
) -> Result<usize, Error> {
let len = len(puback, properties);
buffer.put_u8(0x40);
let count = write_remaining_length(buffer, len)?;
buffer.put_u16(puback.pkid);
if puback.reason == PubAckReason::Success && properties.is_none() {
return Ok(4);
}
buffer.put_u8(code(puback.reason));
if let Some(p) = properties {
properties::write(p, buffer)?;
} else {
write_remaining_length(buffer, 0)?;
}
Ok(1 + count + len)
}
mod properties {
use super::*;
pub fn len(properties: &PubAckProperties) -> usize {
let mut len = 0;
if let Some(reason) = &properties.reason_string {
len += 1 + 2 + reason.len();
}
for (key, value) in properties.user_properties.iter() {
len += 1 + 2 + key.len() + 2 + value.len();
}
len
}
pub fn read(mut bytes: &mut Bytes) -> Result<Option<PubAckProperties>, Error> {
let mut reason_string = None;
let mut user_properties = Vec::new();
let (properties_len_len, properties_len) = length(bytes.iter())?;
bytes.advance(properties_len_len);
if properties_len == 0 {
return Ok(None);
}
let mut cursor = 0;
while cursor < properties_len {
let prop = read_u8(bytes)?;
cursor += 1;
match property(prop)? {
PropertyType::ReasonString => {
let reason = read_mqtt_string(bytes)?;
cursor += 2 + reason.len();
reason_string = Some(reason);
}
PropertyType::UserProperty => {
let key = read_mqtt_string(bytes)?;
let value = read_mqtt_string(bytes)?;
cursor += 2 + key.len() + 2 + value.len();
user_properties.push((key, value));
}
_ => return Err(Error::InvalidPropertyType(prop)),
}
}
Ok(Some(PubAckProperties {
reason_string,
user_properties,
}))
}
pub fn write(properties: &PubAckProperties, buffer: &mut BytesMut) -> Result<(), Error> {
let len = len(properties);
write_remaining_length(buffer, len)?;
if let Some(reason) = &properties.reason_string {
buffer.put_u8(PropertyType::ReasonString as u8);
write_mqtt_string(buffer, reason);
}
for (key, value) in properties.user_properties.iter() {
buffer.put_u8(PropertyType::UserProperty as u8);
write_mqtt_string(buffer, key);
write_mqtt_string(buffer, value);
}
Ok(())
}
}
fn reason(num: u8) -> Result<PubAckReason, Error> {
let code = match num {
0 => PubAckReason::Success,
16 => PubAckReason::NoMatchingSubscribers,
128 => PubAckReason::UnspecifiedError,
131 => PubAckReason::ImplementationSpecificError,
135 => PubAckReason::NotAuthorized,
144 => PubAckReason::TopicNameInvalid,
145 => PubAckReason::PacketIdentifierInUse,
151 => PubAckReason::QuotaExceeded,
153 => PubAckReason::PayloadFormatInvalid,
num => return Err(Error::InvalidConnectReturnCode(num)),
};
Ok(code)
}
fn code(reason: PubAckReason) -> u8 {
match reason {
PubAckReason::Success => 0,
PubAckReason::NoMatchingSubscribers => 16,
PubAckReason::UnspecifiedError => 128,
PubAckReason::ImplementationSpecificError => 131,
PubAckReason::NotAuthorized => 135,
PubAckReason::TopicNameInvalid => 144,
PubAckReason::PacketIdentifierInUse => 145,
PubAckReason::QuotaExceeded => 151,
PubAckReason::PayloadFormatInvalid => 153,
}
}