// Copyright 2016 coroutine-rs Developers
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// http://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.

extern crate cc;

use std::env;
use std::path::PathBuf;

fn main() {
    let target: String = env::var("TARGET").unwrap();
    let is_win_gnu = target.ends_with("windows-gnu");
    let is_win_msvc = target.ends_with("windows-msvc");
    let is_win = is_win_gnu || is_win_msvc;

    let arch = match target.split('-').next().unwrap() {
        "arm" | "armv7" | "armv7s" => "arm",
        "arm64" | "aarch64" => "arm64",
        "x86" | "i386" | "i486" | "i586" | "i686" => "i386",
        "mips" | "mipsel" => "mips32",
        "powerpc" => "ppc32",
        "powerpc64" => "ppc64",
        "x86_64" => "x86_64",
        _ => {
            panic!("Unsupported architecture: {}", target);
        }
    };

    let abi = match arch {
        "arm" | "arm64" => "aapcs",
        "mips32" => "o32",
        _ => {
            if is_win {
                "ms"
            } else {
                "sysv"
            }
        }
    };

    let format = if is_win {
        "pe"
    } else if target.contains("apple") {
        "macho"
    } else if target.ends_with("aix") {
        "xcoff"
    } else {
        "elf"
    };

    let (asm, ext) = if is_win_msvc {
        if arch == "arm" {
            ("armasm", "asm")
        } else {
            ("masm", "asm")
        }
    } else if is_win_gnu {
        ("gas", "asm")
    } else {
        ("gas", "S")
    };

    let prefixes = ["jump", "make"];
    let base_path: PathBuf = ["src", "context", "asm"].iter().collect();
    let mut config = cc::Build::new();

    config.define("BOOST_CONTEXT_EXPORT", None);

    if is_win_gnu {
        config.flag("-x").flag("assembler-with-cpp");
    }

    for prefix in prefixes.iter() {
        let file_name: [&str; 11] = [prefix, "_", arch, "_", abi, "_", format, "_", asm, ".", ext];
        let file_name = file_name.concat();

        let mut path = base_path.clone();
        path.push(file_name);
        config.file(path.to_str().unwrap());
    }

    config.compile("libboost_context.a");
}