use std::path::PathBuf;
use std::process::Command;

use structopt::StructOpt;

#[derive(Debug, Copy, Clone)]
pub enum Architecture {
    BpfEl,
    BpfEb,
}

impl std::str::FromStr for Architecture {
    type Err = String;

    fn from_str(s: &str) -> Result<Self, Self::Err> {
        Ok(match s {
            "bpfel-unknown-none" => Architecture::BpfEl,
            "bpfeb-unknown-none" => Architecture::BpfEb,
            _ => return Err("invalid target".to_owned()),
        })
    }
}

impl std::fmt::Display for Architecture {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.write_str(match self {
            Architecture::BpfEl => "bpfel-unknown-none",
            Architecture::BpfEb => "bpfeb-unknown-none",
        })
    }
}

#[derive(StructOpt)]
pub struct Options {
    #[structopt(default_value = "bpfel-unknown-none", long)]
    target: Architecture,
    #[structopt(long)]
    release: bool,
}

pub fn build(opts: Options) -> Result<(), anyhow::Error> {
    let dir = PathBuf::from("aya-log-ebpf");
    let target = format!("--target={}", opts.target);
    let mut args = vec![
        "+nightly",
        "build",
        "--verbose",
        target.as_str(),
        "-Z",
        "build-std=core",
    ];
    if opts.release {
        args.push("--release")
    }
    let status = Command::new("cargo")
        .current_dir(&dir)
        .args(&args)
        .status()
        .expect("failed to build bpf examples");
    assert!(status.success());
    Ok(())
}