// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

//! Check license of third-party deps by inspecting src/vendor

use std::fs::File;
use std::io::Read;
use std::path::Path;

static LICENSES: &'static [&'static str] = &[
    "MIT/Apache-2.0",
    "MIT / Apache-2.0",
    "Apache-2.0/MIT",
    "MIT OR Apache-2.0",
    "MIT",
    "Unlicense/MIT",
];

/// These MPL licensed projects are acceptable, but only these.
static EXCEPTIONS: &'static [&'static str] = &[
    "mdbook",
    "openssl",
    "pest",
    "thread-id",
];

pub fn check(path: &Path, bad: &mut bool) {
    let path = path.join("vendor");
    assert!(path.exists(), "vendor directory missing");
    let mut saw_dir = false;
    'next_path: for dir in t!(path.read_dir()) {
        saw_dir = true;
        let dir = t!(dir);

        // skip our exceptions
        for exception in EXCEPTIONS {
            if dir.path()
                .to_str()
                .unwrap()
                .contains(&format!("src/vendor/{}", exception)) {
                continue 'next_path;
            }
        }

        let toml = dir.path().join("Cargo.toml");
        if !check_license(&toml) {
            *bad = true;
        }
    }
    assert!(saw_dir, "no vendored source");
}

fn check_license(path: &Path) -> bool {
    if !path.exists() {
        panic!("{} does not exist", path.display());
    }
    let mut contents = String::new();
    t!(t!(File::open(path)).read_to_string(&mut contents));

    let mut found_license = false;
    for line in contents.lines() {
        if !line.starts_with("license") {
            continue;
        }
        let license = extract_license(line);
        if !LICENSES.contains(&&*license) {
            println!("invalid license {} in {}", license, path.display());
            return false;
        }
        found_license = true;
        break;
    }
    if !found_license {
        println!("no license in {}", path.display());
        return false;
    }

    true
}

fn extract_license(line: &str) -> String {
    let first_quote = line.find('"');
    let last_quote = line.rfind('"');
    if let (Some(f), Some(l)) = (first_quote, last_quote) {
        let license = &line[f + 1 .. l];
        license.into()
    } else {
        "bad-license-parse".into()
    }
}
