"use strict";

const fs = require("fs");
const os = require("os");
const path = require("path");

const co = require("co");
const destroy = require("destroy");
const _mkdirp = require("mkdirp");
const urllib = require("urllib");

const getLinuxDistroRoute = require("./get_linux_distro_route");
const pkg = require("../package");

let REGISTRY_MIRROR =
    process.env.NODE_ROCKETMQ_REGISTRY ||
    "https://opensource-rocketmq-client.oss-cn-hangzhou.aliyuncs.com";
if(!REGISTRY_MIRROR.endsWith("/")) REGISTRY_MIRROR += "/";

const CPP_SDK_VERSION = pkg.cppSDKVersion;
const LIB_DIR = path.join(__dirname, "..", "deps", "lib");
const URL_ROOT = `${REGISTRY_MIRROR}cpp-client`;

function mkdirp(dir) {
    return new Promise((resolve, reject) => {
        _mkdirp(dir, null, err => {
            if(err) reject(err);
            else resolve();
        });
    });
}

function *getUrlArray() {
    const platform = os.platform();
    const ret = [];
    let distro;

    switch(platform) {
    case "win32":
        ret.push(`${URL_ROOT}/windows/${CPP_SDK_VERSION}/rocketmq-client-cpp.dll`);
        ret.push(`${URL_ROOT}/windows/${CPP_SDK_VERSION}/rocketmq-client-cpp.lib`);
        break;

    case "darwin":
        ret.push(`${URL_ROOT}/mac/${CPP_SDK_VERSION}/librocketmq.dylib`);
        break;

    case "linux":
        distro = yield getLinuxDistroRoute();
        ret.push(`${URL_ROOT}/linux/${CPP_SDK_VERSION}/${distro}/librocketmq.a`);
        break;

    default: throw new Error(`Unsupported platform ${platform}`);
    }

    return ret;
}

co(function *() {
    let urls;
    try {
        urls = yield getUrlArray();
    } catch(e) {
        console.error(`[rocketmq sdk] [error] ${e.message}`);
        process.exit(4);
    }

    yield mkdirp(LIB_DIR);
    let writeTimes = 0;
    for(const url of urls) {
        console.log(`[rocketmq sdk] [info] downloading [${url}]...`);

        const resp = yield urllib.request(url, {
            timeout: 60000 * 5,
            followRedirect: true,
            streaming: true
        });

        if(resp.status !== 200) {
            destroy(resp.res);
            console.error(`[rocketmq sdk] [error] error status ${resp.status} while downloading [${url}].`);
            process.exit(4);
        }

        const readStream = resp.res;
        const filename = path.join(LIB_DIR, path.basename(url));
        const writeStream = fs.createWriteStream(filename, {
            encoding: "binary"
        });

        // eslint-disable-next-line
        function handleDownladCallback(err) {
            if(err) {
                console.error(`[rocketmq sdk] [error] error occurred while downloading [${url}] to [${filename}].`);
                console.error(err.stack);
                process.exit(4);
            }

            writeTimes++;
            destroy(resp.res);

            console.log(`[rocketmq sdk] [info] downloaded library [${url}].`);
            if(writeTimes === urls.length) {
                console.log("[rocketmq sdk] [info] all libraries have been written to disk.");
                process.exit(0);
            }
        }

        readStream.on("error", handleDownladCallback);
        writeStream.on("error", handleDownladCallback);
        writeStream.on("finish", handleDownladCallback);

        readStream.pipe(writeStream);
    }
});