rust-mqtt/src/packet/control_packet.rs

use heapless::Vec;

use crate::packet::mqtt_packet::Packet;
use crate::utils::buffer_reader::BinaryData;
use crate::utils::buffer_reader::BuffReader;
use crate::utils::buffer_reader::EncodedString;
use crate::utils::buffer_reader::ParseError;

use super::packet_type::PacketType;
use super::property::Property;

pub const MAX_PROPERTIES: usize = 18;
pub const MAX_WILL_PROPERTIES: usize = 7;

pub struct ControlPacket<'a> {
    // 7 - 4 mqtt control packet type, 3-0 flagy
    pub fixed_header: u8,
    // 1 - 4 B lenght of variable header + len of payload
    pub remain_len: u32,

    // variable header
    //optional  prida se pouze u packetu ve kterych ma co delat
    pub packet_identifier: u16,
    pub protocol_name_len: u16,
    pub protocol_name: u32,
    pub protocol_version: u8,
    pub connect_flags: u8,
    pub keep_alive: u16,
    // property len
    pub property_len: u32,

    // properties
    pub properties: Vec<Property<'a>, MAX_PROPERTIES>,

    //payload
    pub client_id: EncodedString<'a>,
    // property len
    pub will_property_len: u32,
    pub will_properties: Vec<Property<'a>, MAX_WILL_PROPERTIES>,
    pub will_topic: EncodedString<'a>,
    pub will_payload: BinaryData<'a>,
    pub username: EncodedString<'a>,
    pub password: BinaryData<'a>,
}

impl<'a> ControlPacket<'a> {
    pub fn clean(
        properties: Vec<Property<'a>, MAX_PROPERTIES>,
        will_properties: Vec<Property<'a>, MAX_WILL_PROPERTIES>,
    ) -> Self {
        Self {
            fixed_header: 0x00,
            remain_len: 0,
            packet_identifier: 0,
            protocol_name_len: 0,
            protocol_name: 0,
            protocol_version: 5,
            connect_flags: 0,
            keep_alive: 0,
            property_len: 0,
            properties,
            client_id: EncodedString::new(),
            will_property_len: 0,
            will_properties,
            will_topic: EncodedString::new(),
            will_payload: BinaryData::new(),
            username: EncodedString::new(),
            password: BinaryData::new(),
        }
    }

    pub fn get_reason_code(&self) {
        log::info!("Getting reason code!");
    }

    pub fn add_packet_type(&mut self, new_packet_type: PacketType) {
        self.fixed_header = self.fixed_header & 0x0F;
        self.fixed_header = self.fixed_header | <PacketType as Into<u8>>::into(new_packet_type);
    }

    pub fn add_flags(&mut self, dup: bool, qos: u8, retain: bool) {
        let cur_type: u8 = self.fixed_header & 0xF0;
        if cur_type != 0x30 {
            log::error!("Cannot add flags into packet with other than PUBLISH type");
            return;
        }
        let mut flags: u8 = 0x00;
        if dup {
            flags = flags | 0x08;
        }
        if qos == 1 {
            flags = flags | 0x02;
        }
        if qos == 2 {
            flags = flags | 0x04;
        }
        if retain {
            flags = flags | 0x01;
        }
        self.fixed_header = cur_type | flags;
    }

    pub fn decode_will_properties(&mut self, buff_reader: &mut BuffReader<'a>) {
        //todo: need to check if we are parsing only will properties
        let will_property_len = buff_reader.read_variable_byte_int().unwrap();
        let mut x: u32 = 0;
        let mut prop: Result<Property, ParseError>;
        loop {
            let mut res: Property;
            prop = Property::decode(buff_reader);
            if let Ok(res) = prop {
                log::info!("Will property parsed: {:?}", res);
                x = x + res.len() as u32 + 1;
                self.will_properties.push(res);
            } else {
                // error handlo
                log::error!("Problem during property decoding");
            }

            if x == will_property_len {
                break;
            }
        }
    }

    pub fn decode_payload(&mut self, buff_reader: &mut BuffReader<'a>) {
        self.client_id = buff_reader.read_string().unwrap();
        if self.connect_flags & (1 << 2) == 1 {
            self.decode_will_properties(buff_reader);
            self.will_topic = buff_reader.read_string().unwrap();
            self.will_payload = buff_reader.read_binary().unwrap();
        }

        if self.connect_flags & (1 << 7) == 1 {
            self.username = buff_reader.read_string().unwrap();
        }
        if self.connect_flags & (1 << 6) == 1 {
            self.password = buff_reader.read_binary().unwrap();
        }
    }

    pub fn decode_control_packet(&mut self, buff_reader: &mut BuffReader<'a>) {
        if self.decode_fixed_header(buff_reader) != (PacketType::Connect).into() {
            log::error!("Packet you are trying to decode is not CONNECT packet!");
        }
        self.packet_identifier = 0;
        self.protocol_name_len = buff_reader.read_u16().unwrap();
        self.protocol_name = buff_reader.read_u32().unwrap();
        self.protocol_version = buff_reader.read_u8().unwrap();
        self.connect_flags = buff_reader.read_u8().unwrap();
        self.keep_alive = buff_reader.read_u16().unwrap();
        self.decode_properties(buff_reader);
        self.decode_payload(buff_reader);
    }
}

impl<'a> Packet<'a> for ControlPacket<'a> {
    fn encode(&mut self, buffer: &mut [u8]) {}

    fn decode(&mut self, buff_reader: &mut BuffReader<'a>) {
        log::error!("Decode function is not available for control packet!")
        //self.decode_control_packet(buff_reader);
    }

    fn set_property_len(&mut self, value: u32) {
        self.property_len = value;
    }

    fn get_property_len(&mut self) -> u32 {
        return self.property_len;
    }

    fn push_to_properties(&mut self, property: Property<'a>) {
        self.properties.push(property);
    }

    fn set_fixed_header(& mut self, header: u8) {
        self.fixed_header = header;
    }

    fn set_remaining_len(& mut self, remaining_len: u32) {
        self.remain_len = remaining_len;
    }

    fn decode_properties(&mut self, buff_reader: &mut BuffReader<'a>) {
        self.property_len = buff_reader.read_variable_byte_int().unwrap();
        let mut x: u32 = 0;
        let mut prop: Result<Property, ParseError>;
        loop {
            let mut res: Property;
            prop = Property::decode(buff_reader);
            if let Ok(res) = prop {
                log::info!("Parsed property {:?}", res);
                x = x + res.len() as u32 + 1;
                self.properties.push(res);
            } else {
                // error handlo
                log::error!("Problem during property decoding");
            }

            if x == self.property_len {
                break;
            }
        }
    }
}