'use strict';

exports = module.exports = {
    removePrivateFields,
    injectPrivateFields,
    upsert,
    get,
    del,
    wait,
    verifyDomainConfig
};

const assert = require('node:assert'),
    BoxError = require('../boxerror.js'),
    constants = require('../constants.js'),
    debug = require('debug')('box:dns/hetznercloud'),
    dig = require('../dig.js'),
    dns = require('../dns.js'),
    promiseRetry = require('../promise-retry.js'),
    safe = require('safetydance'),
    superagent = require('@cloudron/superagent'),
    waitForDns = require('./waitfordns.js');

// https://docs.hetzner.cloud/reference/cloud

const ENDPOINT = 'https://api.hetzner.cloud/v1';

function formatError(response) {
    return `Hetzner DNS error ${response.status} ${response.text}`;
}

function removePrivateFields(domainObject) {
    delete domainObject.config.token;
    return domainObject;
}

function injectPrivateFields(newConfig, currentConfig) {
    if (!Object.hasOwn(newConfig, 'token')) newConfig.token = currentConfig.token;
}

async function getZone(domainConfig, zoneName) {
    assert.strictEqual(typeof domainConfig, 'object');
    assert.strictEqual(typeof zoneName, 'string');

    const [error, response] = await safe(superagent.get(`${ENDPOINT}/zones`)
        .set('Authorization', `Bearer ${domainConfig.token}`)
        .query({ search_name: zoneName })
        .timeout(30 * 1000)
        .retry(5)
        .ok(() => true));
    if (error) throw new BoxError(BoxError.NETWORK_ERROR, error);
    if (response.status === 401 || response.status === 403) throw new BoxError(BoxError.ACCESS_DENIED, formatError(response));
    if (response.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));

    if (!Array.isArray(response.body.zones)) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));

    const zone = response.body.zones.find(z => z.name === zoneName);
    if (!zone) throw new BoxError(BoxError.NOT_FOUND, formatError(response));
    return zone;
}

async function getRecords(domainConfig, zone, name, type) {
    assert.strictEqual(typeof domainConfig, 'object');
    assert.strictEqual(typeof zone, 'object');
    assert.strictEqual(typeof name, 'string');
    assert.strictEqual(typeof type, 'string');

    debug(`getRecords: getting dns records of ${zone.name} with ${name} and type ${type}`);

    const [error, response] = await safe(superagent.get(`${ENDPOINT}/zones/${zone.id}/rrsets/${name}/${type.toUpperCase()}`)
        .set('Authorization', `Bearer ${domainConfig.token}`)
        .timeout(30 * 1000)
        .retry(5)
        .ok(() => true));

    if (error) throw new BoxError(BoxError.NETWORK_ERROR, error);
    if (response.status === 404) return [];
    if (response.status === 401 || response.status === 403) throw new BoxError(BoxError.ACCESS_DENIED, formatError(response));
    if (response.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));

    return response.body.rrset.records;
}

async function waitForAction(domainConfig, id) {
    assert.strictEqual(typeof domainConfig, 'object');
    assert.strictEqual(typeof id, 'number');

    await promiseRetry({ times: 100, interval: 1000, debug }, async () => {
        const [error, response] = await safe(superagent.get(`${ENDPOINT}/actions/${id}`)
            .set('Authorization', `Bearer ${domainConfig.token}`)
            .timeout(30 * 1000)
            .retry(5)
            .ok(() => true));

        if (error) throw new BoxError(BoxError.NETWORK_ERROR, error);
        if (response.status === 404) return [];
        if (response.status === 401 || response.status === 403) throw new BoxError(BoxError.ACCESS_DENIED, formatError(response));
        if (response.status !== 200) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));
        if (response.body.action.status !== 'success') throw new BoxError(BoxError.TRY_AGAIN, 'action not done yet');
    });
}

async function upsert(domainObject, location, type, values) {
    assert.strictEqual(typeof domainObject, 'object');
    assert.strictEqual(typeof location, 'string');
    assert.strictEqual(typeof type, 'string');
    assert(Array.isArray(values));

    const domainConfig = domainObject.config,
        zoneName = domainObject.zoneName,
        name = dns.getName(domainObject, location, type) || '@';

    debug(`upsert: ${name} for zone ${zoneName} of type ${type} with values ${JSON.stringify(values)}`);

    const zone = await getZone(domainConfig, zoneName);
    const records = await getRecords(domainConfig, zone, name, type);

    // update means first delete then recreate
    if (records.length) await del(domainObject, location, type, values);

    const data = {
        name,
        type,
        ttl: 60,
        records: values.map(v => { return { value: v, comment: 'managed by cloudron' }; }),
        labels: {
            managedBy: 'cloudron'
        }
    };

    const [error, response] = await safe(superagent.post(`${ENDPOINT}/zones/${zone.id}/rrsets`)
        .set('Authorization', `Bearer ${domainConfig.token}`)
        .send(data)
        .timeout(30 * 1000)
        .retry(5)
        .ok(() => true));

    if (error) throw new BoxError(BoxError.NETWORK_ERROR, error);
    if (response.status === 403 || response.status === 401) throw new BoxError(BoxError.ACCESS_DENIED, formatError(response));
    if (response.status === 422) throw new BoxError(BoxError.BAD_FIELD, response.body.message);
    if (response.status !== 201) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));

    await waitForAction(domainConfig, response.body.action.id);
}

async function get(domainObject, location, type) {
    assert.strictEqual(typeof domainObject, 'object');
    assert.strictEqual(typeof location, 'string');
    assert.strictEqual(typeof type, 'string');

    const domainConfig = domainObject.config,
        zoneName = domainObject.zoneName,
        name = dns.getName(domainObject, location, type) || '@';

    const zone = await getZone(domainConfig, zoneName);
    const result = await getRecords(domainConfig, zone, name, type);

    return result.map(function (record) { return record.value; });
}

async function del(domainObject, location, type, values) {
    assert.strictEqual(typeof domainObject, 'object');
    assert.strictEqual(typeof location, 'string');
    assert.strictEqual(typeof type, 'string');
    assert(Array.isArray(values));

    const domainConfig = domainObject.config,
        zoneName = domainObject.zoneName,
        name = dns.getName(domainObject, location, type) || '@';

    const zone = await getZone(domainConfig, zoneName);
    const records = await getRecords(domainConfig, zone, name, type);
    if (records.length === 0) return;

    const [error, response] = await safe(superagent.del(`${ENDPOINT}/zones/${zone.id}/rrsets/${name}/${type}`)
        .set('Authorization', `Bearer ${domainConfig.token}`)
        .timeout(30 * 1000)
        .retry(5)
        .ok(() => true));

    if (error) throw new BoxError(BoxError.NETWORK_ERROR, error);
    if (response.status === 404) return;
    if (response.status === 403 || response.status === 401) throw new BoxError(BoxError.ACCESS_DENIED, formatError(response));
    if (response.status !== 201) throw new BoxError(BoxError.EXTERNAL_ERROR, formatError(response));

    await waitForAction(domainConfig, response.body.action.id);
}

async function wait(domainObject, subdomain, type, value, options) {
    assert.strictEqual(typeof domainObject, 'object');
    assert.strictEqual(typeof subdomain, 'string');
    assert.strictEqual(typeof type, 'string');
    assert.strictEqual(typeof value, 'string');
    assert(options && typeof options === 'object'); // { interval: 5000, times: 50000 }

    const fqdn = dns.fqdn(subdomain, domainObject.domain);

    await waitForDns(fqdn, domainObject.zoneName, type, value, options);
}

async function verifyDomainConfig(domainObject) {
    assert.strictEqual(typeof domainObject, 'object');

    const domainConfig = domainObject.config,
        zoneName = domainObject.zoneName;

    if (!domainConfig.token || typeof domainConfig.token !== 'string') throw new BoxError(BoxError.BAD_FIELD, 'token must be a non-empty string');
    if ('customNameservers' in domainConfig && typeof domainConfig.customNameservers !== 'boolean') throw new BoxError(BoxError.BAD_FIELD, 'customNameservers must be a boolean');

    const ip = '127.0.0.1';

    const credentials = {
        token: domainConfig.token,
        customNameservers: !!domainConfig.customNameservers
    };

    if (constants.TEST) return credentials; // this shouldn't be here

    const [error, nameservers] = await safe(dig.resolve(zoneName, 'NS', { timeout: 5000 }));
    if (error && error.code === 'ENOTFOUND') throw new BoxError(BoxError.BAD_FIELD, 'Unable to resolve nameservers for this domain');
    if (error || !nameservers) throw new BoxError(BoxError.BAD_FIELD, error ? error.message : 'Unable to get nameservers');

    // https://docs.hetzner.com/dns-console/dns/general/dns-overview#the-hetzner-online-name-servers-are
    if (!nameservers.every(function (n) { return n.toLowerCase().search(/hetzner|your-server|second-ns/) !== -1; })) {
        debug('verifyDomainConfig: %j does not contain Hetzner NS', nameservers);
        if (!domainConfig.customNameservers) throw new BoxError(BoxError.BAD_FIELD, 'Domain nameservers are not set to Hetzner');
    }

    const location = 'cloudrontestdns';

    await upsert(domainObject, location, 'A', [ ip ]);
    debug('verifyDomainConfig: Test A record added');

    await del(domainObject, location, 'A', [ ip ]);
    debug('verifyDomainConfig: Test A record removed again');

    return credentials;
}