//! Cgroup socket address programs.
use thiserror::Error;

use crate::generated::bpf_attach_type;

/// Defines where to attach a `CgroupSockAddr` program.
#[derive(Copy, Clone, Debug)]
pub enum CgroupSockAddrAttachType {
    /// Attach to IPv4 bind events.
    Bind4,
    /// Attach to IPv6 bind events.
    Bind6,
    /// Attach to IPv4 connect events.
    Connect4,
    /// Attach to IPv6 connect events.
    Connect6,
    /// Attach to IPv4 getpeername events.
    GetPeerName4,
    /// Attach to IPv6 getpeername events.
    GetPeerName6,
    /// Attach to IPv4 getsockname events.
    GetSockName4,
    /// Attach to IPv6 getsockname events.
    GetSockName6,
    /// Attach to IPv4 udp_sendmsg events.
    UDPSendMsg4,
    /// Attach to IPv6 udp_sendmsg events.
    UDPSendMsg6,
    /// Attach to IPv4 udp_recvmsg events.
    UDPRecvMsg4,
    /// Attach to IPv6 udp_recvmsg events.
    UDPRecvMsg6,
}

impl From<CgroupSockAddrAttachType> for bpf_attach_type {
    fn from(s: CgroupSockAddrAttachType) -> bpf_attach_type {
        match s {
            CgroupSockAddrAttachType::Bind4 => bpf_attach_type::BPF_CGROUP_INET4_BIND,
            CgroupSockAddrAttachType::Bind6 => bpf_attach_type::BPF_CGROUP_INET6_BIND,
            CgroupSockAddrAttachType::Connect4 => bpf_attach_type::BPF_CGROUP_INET4_CONNECT,
            CgroupSockAddrAttachType::Connect6 => bpf_attach_type::BPF_CGROUP_INET6_CONNECT,
            CgroupSockAddrAttachType::GetPeerName4 => bpf_attach_type::BPF_CGROUP_INET4_GETPEERNAME,
            CgroupSockAddrAttachType::GetPeerName6 => bpf_attach_type::BPF_CGROUP_INET6_GETPEERNAME,
            CgroupSockAddrAttachType::GetSockName4 => bpf_attach_type::BPF_CGROUP_INET4_GETSOCKNAME,
            CgroupSockAddrAttachType::GetSockName6 => bpf_attach_type::BPF_CGROUP_INET6_GETSOCKNAME,
            CgroupSockAddrAttachType::UDPSendMsg4 => bpf_attach_type::BPF_CGROUP_UDP4_SENDMSG,
            CgroupSockAddrAttachType::UDPSendMsg6 => bpf_attach_type::BPF_CGROUP_UDP6_SENDMSG,
            CgroupSockAddrAttachType::UDPRecvMsg4 => bpf_attach_type::BPF_CGROUP_UDP4_RECVMSG,
            CgroupSockAddrAttachType::UDPRecvMsg6 => bpf_attach_type::BPF_CGROUP_UDP6_RECVMSG,
        }
    }
}

#[derive(Debug, Error)]
#[error("{0} is not a valid attach type for a CGROUP_SOCK_ADDR program")]
pub(crate) struct InvalidAttachType(String);

impl CgroupSockAddrAttachType {
    pub(crate) fn try_from(value: &str) -> Result<CgroupSockAddrAttachType, InvalidAttachType> {
        match value {
            "bind4" => Ok(CgroupSockAddrAttachType::Bind4),
            "bind6" => Ok(CgroupSockAddrAttachType::Bind6),
            "connect4" => Ok(CgroupSockAddrAttachType::Connect4),
            "connect6" => Ok(CgroupSockAddrAttachType::Connect6),
            "getpeername4" => Ok(CgroupSockAddrAttachType::GetPeerName4),
            "getpeername6" => Ok(CgroupSockAddrAttachType::GetPeerName6),
            "getsockname4" => Ok(CgroupSockAddrAttachType::GetSockName4),
            "getsockname6" => Ok(CgroupSockAddrAttachType::GetSockName6),
            "sendmsg4" => Ok(CgroupSockAddrAttachType::UDPSendMsg4),
            "sendmsg6" => Ok(CgroupSockAddrAttachType::UDPSendMsg6),
            "recvmsg4" => Ok(CgroupSockAddrAttachType::UDPRecvMsg4),
            "recvmsg6" => Ok(CgroupSockAddrAttachType::UDPRecvMsg6),
            _ => Err(InvalidAttachType(value.to_owned())),
        }
    }
}