// Copyright 2017 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.

extern crate cc;
extern crate cmake;

use std::path::PathBuf;
use cc::Build;
use std::{env, str};
use cmake::Config;

fn main() {
    let mut build = build_rocksdb();

    build.cpp(true).file("crocksdb/c.cc");
    if !cfg!(target_os = "windows") {
        build.flag("-std=c++11");
    }
    link_cpp(&mut build);
    build.warnings(false).compile("libcrocksdb.a");
}

fn link_cpp(build: &mut Build) {
    let tool = build.get_compiler();
    let stdlib = if tool.is_like_gnu() {
        "libstdc++.a"
    } else if tool.is_like_clang() {
        "libc++.a"
    } else {
        // Don't link to c++ statically on windows.
        return;
    };
    let output = tool.to_command().arg("--print-file-name").arg(stdlib).output().unwrap();
    if !output.status.success() || output.stdout.is_empty() {
        // fallback to dynamically
        return;
    }
    let path = match str::from_utf8(&output.stdout) {
        Ok(path) => PathBuf::from(path),
        Err(_) => return,
    };
    if !path.is_absolute() {
        return;
    }
    // remove lib prefix and .a postfix.
    println!("cargo:rustc-link-lib=static={}", &stdlib[3..stdlib.len() - 2]);
    println!("cargo:rustc-link-search=native={}", path.parent().unwrap().display());
    build.cpp_link_stdlib(None);
}

fn build_rocksdb() -> Build {
    let mut build = Build::new();
    for e in env::vars() {
        println!("{:?}", e);
    }

    let mut cfg = Config::new("rocksdb");
    if cfg!(feature = "portable") {
        cfg.define("PORTABLE", "ON");
    }
    if cfg!(feature = "sse") {
        cfg.define("FORCE_SSE42", "ON");
    }
    let dst = cfg.register_dep("Z").define("WITH_ZLIB", "ON")
        .register_dep("BZIP2").define("WITH_BZ2", "ON")
        .register_dep("ZSTD").define("WITH_ZSTD", "ON")
        .build_target("rocksdb").build();
    let build_dir = format!("{}/build", dst.display());
    if cfg!(target_os = "windows") {
        let profile = match &*env::var("PROFILE").unwrap_or("debug".to_owned()) {
            "bench" | "release" => "Release",
            _ => "Debug",
        };
        println!("cargo:rustc-link-search=native={}/{}", build_dir, profile);
        build.define("OS_WIN", None);
    } else {
        println!("cargo:rustc-link-search=native={}", build_dir);
        build.define("ROCKSDB_PLATFORM_POSIX", None);
    }
    if cfg!(target_os = "macos") {
        build.define("OS_MACOSX", None);
    }

    let cur_dir = env::current_dir().unwrap();
    build.include(cur_dir.join("rocksdb").join("include"));
    build.include(cur_dir.join("rocksdb"));

    println!("cargo:rustc-link-lib=static=rocksdb");
    println!("cargo:rustc-link-lib=static=z");
    println!("cargo:rustc-link-lib=static=bz2");
    println!("cargo:rustc-link-lib=static=zstd");
    build
}