'use strict';

exports = module.exports = {
    getIPv4,
    getIPv6,
    testIPv4Config,
    testIPv6Config
};

const assert = require('assert'),
    BoxError = require('../boxerror.js'),
    constants = require('../constants.js'),
    debug = require('debug')('box:network/generic'),
    safe = require('safetydance'),
    superagent = require('superagent');

const gCache = { ipv4: {}, ipv6: {} }; // each has { timestamp, value, request }

async function getIPv4(config) {
    assert.strictEqual(typeof config, 'object');

    if (constants.TEST) return '127.0.0.1';

    if (gCache.ipv4.value && (Date.now() - gCache.ipv4.timestamp <= 5 * 60 * 1000)) return gCache.ipv4.value;

    let request = gCache.ipv4.request; // allow reuse for parallel requests
    if (!request) {
        debug('getIPv4: querying ipv4.api.cloudron.io to get server IPv4');
        request = superagent.get('https://ipv4.api.cloudron.io/api/v1/helper/public_ip').timeout(30 * 1000).retry(2).ok(() => true);
        gCache.ipv4.request = request;
    }

    gCache.ipv4.value = null;

    const [networkError, response] = await safe(request);
    gCache.ipv4.request = null;

    if (networkError || response.status !== 200) {
        debug('getIPv4: Error getting IP. %o', networkError);
        throw new BoxError(BoxError.EXTERNAL_ERROR, 'Unable to detect IPv4. API server (ipv4.api.cloudron.io) unreachable');
    }

    if (!response.body && !response.body.ip) {
        debug('getIPv4: Unexpected answer. No "ip" found in response body.', response.body);
        throw new BoxError(BoxError.EXTERNAL_ERROR, 'Unable to detect IPv4. No IP found in response');
    }

    gCache.ipv4.value = response.body.ip;
    gCache.ipv4.timestamp = Date.now();
    return response.body.ip;
}

async function getIPv6(config) {
    assert.strictEqual(typeof config, 'object');

    if (constants.TEST) return '::1';

    if (gCache.ipv6.value && (Date.now() - gCache.ipv6.timestamp <= 5 * 60 * 1000)) return gCache.ipv6.value;

    let request = gCache.ipv6.request; // allow reuse for parallel requests
    if (!request) {
        debug('getIPv6: querying ipv6.api.cloudron.io to get server IPv6');
        request = superagent.get('https://ipv6.api.cloudron.io/api/v1/helper/public_ip').timeout(30 * 1000).retry(2).ok(() => true);
        gCache.ipv6.request = request;
    }

    gCache.ipv6.value = null;

    const [networkError, response] = await safe(request);
    gCache.ipv6.request = null;

    if (networkError || response.status !== 200) {
        debug('getIPv6: Error getting IP. %o', networkError);
        throw new BoxError(BoxError.EXTERNAL_ERROR, 'Unable to detect IPv6. API server (ipv6.api.cloudron.io) unreachable');
    }

    if (!response.body && !response.body.ip) {
        debug('getIPv6: Unexpected answer. No "ip" found in response body.', response.body);
        throw new BoxError(BoxError.EXTERNAL_ERROR, 'Unable to detect IPv6. No IP found in response');
    }

    gCache.ipv6.value = response.body.ip;
    gCache.ipv6.timestamp = Date.now();
    return response.body.ip;
}

async function testIPv4Config(config) {
    assert.strictEqual(typeof config, 'object');

    return null;
}

async function testIPv6Config(config) {
    assert.strictEqual(typeof config, 'object');

    return null;
}