aur_cli 0.1.2

pub(crate) mod error;

use crate::error::Error;
use colored::*;
use directories::UserDirs;
use gumdrop::{Options, ParsingStyle};
use hmac_sha256::Hash;
use itertools::Itertools;
use serde_derive::Deserialize;
use std::ffi::OsString;
use std::fs::{DirEntry, File};
use std::io::{BufWriter, Write};
use std::ops::Not;
use std::path::{Path, PathBuf};
use std::process::Command;

/// Licenses avaiable from the Arch Linux `licenses` package.
///
/// That package contains other licenses, but I've excluded here those unlikely
/// to be used by Rust crates.
const LICENSES: &[&str] = &[
    "AGPL3", "APACHE", "GPL2", "GPL3", "LGPL2.1", "LGPL3", "MPL", "MPL2",
];

#[derive(Options)]
struct Args {
    /// Display this help message.
    help: bool,

    /// Display the current version of this software.
    version: bool,

    /// Unused.
    #[options(free)]
    args: Vec<String>,

    /// Use the MUSL build target to produce a static binary.
    musl: bool,

    /// Don't actually build anything.
    dryrun: bool,
}

enum GitHost {
    Github,
    Gitlab,
}

impl GitHost {
    fn source(&self, package: &Package) -> String {
        match self {
            GitHost::Github => format!(
                "{}/raw/main/{}-$pkgver-x86_64.tar.gz",
                package.repository, package.name
            ),
            GitHost::Gitlab => format!(
                "{}/-/raw/main/{}-$pkgver-x86_64.tar.gz",
                package.repository.replace(".git", ""), package.name
            ),
        }
    }
}

#[derive(Deserialize, Debug)]
struct Config {
    package: Package,
    #[serde(default)]
    bin: Vec<Binary>,
}

impl Config {
    /// The name of the compiled binary that should be copied to the tarball.
    fn binary_name(&self) -> &str {
        self.bin
            .first()
            .map(|bin| bin.name.as_str())
            .unwrap_or(self.package.name.as_str())
    }
}

#[derive(Deserialize, Debug)]
struct Package {
    name: String,
    version: String,
    authors: Vec<String>,
    description: String,
    homepage: String,
    repository: String,
    license: String,
    metadata: Option<Metadata>,
}

#[derive(Deserialize, Debug)]
struct Metadata {
    #[serde(default)]
    depends: Vec<String>,
    #[serde(default)]
    optdepends: Vec<String>,
}

impl std::fmt::Display for Metadata {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self.depends.as_slice() {
            [middle @ .., last] => {
                write!(f, "depends=(")?;
                for item in middle {
                    write!(f, "\"{}\" ", item)?;
                }
                if self.optdepends.is_empty().not() {
                    writeln!(f, "\"{}\")", last)?;
                } else {
                    write!(f, "\"{}\")", last)?;
                }
            }
            [] => {}
        }

        match self.optdepends.as_slice() {
            [middle @ .., last] => {
                write!(f, "optdepends=(")?;
                for item in middle {
                    write!(f, "\"{}\" ", item)?;
                }
                write!(f, "\"{}\")", last)?;
            }
            [] => {}
        }

        Ok(())
    }
}

#[derive(Deserialize, Debug)]
struct Binary {
    name: String,
}

impl Package {
    /// The name of the tarball that should be produced from this `Package`.
    fn tarball(&self) -> String {
        format!("{}-{}-x86_64.tar.gz", self.name, self.version)
    }

    fn git_host(&self) -> Option<GitHost> {
        if self.repository.starts_with("https://github") {
            Some(GitHost::Github)
        } else if self.repository.starts_with("https://gitlab") {
            Some(GitHost::Gitlab)
        } else {
            None
        }
    }
}

fn main() {
    let args = Args::parse_args_or_exit(ParsingStyle::AllOptions);

    if args.version {
        let version = env!("CARGO_PKG_VERSION");
        println!("{}", version);
    } else if let Err(e) = work(args) {
        eprintln!("{} {}: {}", "::".bold(), "Error".bold().red(), e);
        std::process::exit(1)
    } else {
        println!("{} Create PKGBUILD {}", "::".bold(), "Done.".bold().green());
        if let Ok(_) = doe::system!("makepkg --printsrcinfo > .SRCINFO"){
            println!("{} Create .SRCINFO {}", "::".bold(), "Done.".bold().green());
        }
    }
}

fn work(args: Args) -> Result<(), Error> {
    // We can't proceed if the user has specified `--musl` but doesn't have the
    // target installed.
    if args.musl {
        p("Checking for musl toolchain...".bold());
        musl_check()?
    }

    let config = cargo_config()?;
    let license = if must_copy_license(&config.package.license) {
        p("LICENSE file will be installed manually.".bold().yellow());
        Some(license_file()?)
    } else {
        let licence = include_str!("../LICENSE");
        std::fs::write("./LICENSE", licence).unwrap();
        None
    };

    if args.dryrun.not() {
        release_build(args.musl)?;
        tarball(args.musl, license.as_ref(), &config)?;
        let sha256: String = sha256sum(&config.package)?;

        // Write the PKGBUILD.
        let file = BufWriter::new(File::create("PKGBUILD")?);
        pkgbuild(file, &config, &sha256, license.as_ref())?;
    }

    Ok(())
}

fn cargo_config() -> Result<Config, Error> {
    let content = std::fs::read_to_string("Cargo.toml")?;
    let proj: Config = toml::from_str(&content)?;
    Ok(proj)
}

/// If a AUR package's license isn't included in `/usr/share/licenses/common/`,
/// then it must be installed manually by the PKGBUILD. MIT is such a missing
/// license, and since many Rust crates use MIT we must make this check.
fn must_copy_license(license: &str) -> bool {
    LICENSES.contains(&license).not()
}

/// The path to the `LICENSE` file.
fn license_file() -> Result<DirEntry, Error> {
    std::fs::read_dir(".")?
        .filter_map(|entry| entry.ok())
        .find(|entry| {
            entry
                .file_name()
                .to_str()
                .map(|s| s.starts_with("LICENSE"))
                .unwrap_or(false)
        })
        .ok_or(Error::MissingLicense)
}

/// Write a legal PKGBUILD to some `Write` instance (a `File` in this case).
fn pkgbuild<T: Write>(
    mut file: T,
    config: &Config,
    sha256: &str,
    license: Option<&DirEntry>,
) -> Result<(), Error> {
    let package = &config.package;
    let authors = package
        .authors
        .iter()
        .map(|a| format!("# Maintainer: {}", a))
        .join("\n");
    let source = package
        .git_host()
        .unwrap_or(GitHost::Gitlab)
        .source(&config.package);

    writeln!(file, "{}", authors)?;
    writeln!(file, "#")?;
    writeln!(file)?;
    writeln!(file, "pkgname={}", package.name)?;
    writeln!(file, "pkgver={}", package.version)?;
    writeln!(file, "pkgrel=1")?;
    writeln!(file, "pkgdesc=\"{}\"", package.description)?;
    writeln!(file, "url=\"{}\"", package.homepage)?;
    writeln!(file, "license=(\"{}\")", package.license)?;
    writeln!(file, "arch=(\"x86_64\")")?;
    writeln!(file, "provides=(\"{}\")", package.name)?;
    writeln!(file, "conflicts=(\"{}\")", package.name)?;

    if let Some(metadata) = package.metadata.as_ref() {
        writeln!(file, "{}", metadata)?;
    }

    writeln!(file, "source=(\"{}\")", source)?;
    writeln!(file, "sha256sums=(\"{}\")", sha256)?;
    writeln!(file)?;
    writeln!(file, "package() {{")?;
    writeln!(
        file,
        "    install -Dm755 {} -t \"$pkgdir/usr/bin\"",
        config.binary_name()
    )?;

    if let Some(lic) = license {
        let file_name = lic
            .file_name()
            .into_string()
            .map_err(|_| Error::Utf8OsString)?;
        writeln!(
            file,
            "    install -Dm644 {} \"$pkgdir/usr/share/licenses/$pkgname/{}\"",
            file_name, file_name
        )?;
    }

    writeln!(file, "}}")?;
    Ok(())
}

/// Run `cargo build --release`, potentially building statically.
fn release_build(musl: bool) -> Result<(), Error> {
    let mut args = vec!["build", "--release"];

    if musl {
        args.push("--target=x86_64-unknown-linux-musl");
    }

    p("Running release build...".bold());
    Command::new("cargo").args(args).status()?;
    Ok(())
}

fn tarball(musl: bool, license: Option<&DirEntry>, config: &Config) -> Result<(), Error> {
    let target_dir: OsString = match std::env::var_os("CARGO_TARGET_DIR") {
        Some(p) => p,
        None => {
            let path = PathBuf::from("./target");
            if path.is_dir(){
                "target".into()
            }else{
                let user_dirs = UserDirs::new().unwrap();
                let home = user_dirs.home_dir();
                let cargo_config = format!("{}/.cargo/config",home.to_string_lossy().to_string());
                let config_string = std::fs::read_to_string(cargo_config).unwrap();
                let cargo_toml = tsu::toml_from_str(config_string);
                let build = cargo_toml.get("build").unwrap();
                let target_dir = build.get("target-dir").unwrap().as_str().unwrap();
                format!("{}/{}",home.to_string_lossy(),target_dir).into()
            }
            },
    };

    let release_dir = if musl {
        "x86_64-unknown-linux-musl/release"
    } else {
        "release"
    };

    let binary_name = config.binary_name();
    let mut binary: PathBuf = target_dir.into();
    binary.push(release_dir);
    binary.push(binary_name);

    strip(&binary)?;
    std::fs::copy(binary, binary_name)?;

    // Create the tarball.
    p("Packing tarball...".bold());
    let mut command = Command::new("tar");
    command
        .arg("czf")
        .arg(config.package.tarball())
        .arg(binary_name);
    if let Some(lic) = license {
        command.arg(lic.path());
    }
    command.status()?;

    std::fs::remove_file(binary_name)?;

    Ok(())
}

/// Strip the release binary, so that we aren't compressing more bytes than we
/// need to.
fn strip(path: &Path) -> Result<(), Error> {
    p("Stripping binary...".bold());
    Command::new("strip").arg(path).status()?;
    Ok(()) // FIXME Would love to use my `void` package here and elsewhere.
}

fn sha256sum(package: &Package) -> Result<String, Error> {
    let bytes = std::fs::read(package.tarball())?;
    let digest = Hash::hash(&bytes);
    let hex = digest.iter().map(|u| format!("{:02x}", u)).collect();
    Ok(hex)
}

/// Does the user have the `x86_64-unknown-linux-musl` target installed?
fn musl_check() -> Result<(), Error> {
    let args = vec!["target", "list", "--installed"];
    let output = Command::new("rustup").args(args).output()?.stdout;
    let installed = std::str::from_utf8(&output)?
        .lines()
        .any(|tc| tc == "x86_64-unknown-linux-musl");

    if installed {
        Ok(())
    } else {
        Err(Error::MissingTarget)
    }
}

fn p(msg: ColoredString) {
    println!("{} {}", "::".bold(), msg)
}