/* jslint node:true */

'use strict';

exports = module.exports = {
    get,
    set,
    del,

    initSecrets,

    ACME_ACCOUNT_KEY: 'acme_account_key',
    ADDON_TURN_SECRET: 'addon_turn_secret',
    DHPARAMS: 'dhparams',
    SFTP_PUBLIC_KEY: 'sftp_public_key',
    SFTP_PRIVATE_KEY: 'sftp_private_key',

    CERT_PREFIX: 'cert',

    _clear: clear
};

const assert = require('assert'),
    BoxError = require('./boxerror.js'),
    constants = require('./constants.js'),
    crypto = require('crypto'),
    database = require('./database.js'),
    debug = require('debug')('box:blobs'),
    paths = require('./paths.js'),
    safe = require('safetydance');

const BLOBS_FIELDS = [ 'id', 'value' ].join(',');

async function get(id) {
    assert.strictEqual(typeof id, 'string');

    const result = await database.query(`SELECT ${BLOBS_FIELDS} FROM blobs WHERE id = ?`, [ id ]);
    if (result.length === 0) return null;
    return result[0].value;
}

async function set(id, value) {
    assert.strictEqual(typeof id, 'string');
    assert(value === null || Buffer.isBuffer(value));

    await database.query('INSERT INTO blobs (id, value) VALUES (?, ?) ON DUPLICATE KEY UPDATE value=VALUES(value)', [ id, value ]);
}

async function del(id) {
    await database.query('DELETE FROM blobs WHERE id=?', [ id ]);
}

async function clear() {
    await database.query('DELETE FROM blobs');
}

async function initSecrets() {
    let acmeAccountKey = await get(exports.ACME_ACCOUNT_KEY);
    if (!acmeAccountKey) {
        acmeAccountKey = safe.child_process.execSync('openssl genrsa 4096');
        if (!acmeAccountKey) throw new BoxError(BoxError.OPENSSL_ERROR, `Could not generate acme account key: ${safe.error.message}`);
        await set(exports.ACME_ACCOUNT_KEY, acmeAccountKey);
    }

    let turnSecret = await get(exports.ADDON_TURN_SECRET);
    if (!turnSecret) {
        turnSecret = 'a' + crypto.randomBytes(15).toString('hex'); // prefix with a to ensure string starts with a letter
        await set(exports.ADDON_TURN_SECRET, Buffer.from(turnSecret));
    }

    if (!constants.TEST) {
        let dhparams = await get(exports.DHPARAMS);
        if (!dhparams) {
            debug('initSecrets: generating dhparams.pem. this takes forever');
            dhparams = safe.child_process.execSync('openssl dhparam 2048');
            if (!dhparams) throw new BoxError(BoxError.OPENSSL_ERROR, safe.error);
            if (!safe.fs.writeFileSync(paths.DHPARAMS_FILE, dhparams)) throw new BoxError(BoxError.FS_ERROR, `Could not save dhparams.pem: ${safe.error.message}`);
            await set(exports.DHPARAMS, dhparams);
        } else if (!safe.fs.existsSync(paths.DHPARAMS_FILE)) {
            if (!safe.fs.writeFileSync(paths.DHPARAMS_FILE, dhparams)) throw new BoxError(BoxError.FS_ERROR, `Could not save dhparams.pem: ${safe.error.message}`);
        }
    }

    let sftpPrivateKey = await get(exports.SFTP_PRIVATE_KEY);
    let sftpPublicKey = await get(exports.SFTP_PUBLIC_KEY);

    if (!sftpPrivateKey || !sftpPublicKey) {
        debug('initSecrets: generate sftp keys');
        if (constants.TEST) {
            safe.fs.unlinkSync(paths.SFTP_PUBLIC_KEY_FILE);
            safe.fs.unlinkSync(paths.SFTP_PRIVATE_KEY_FILE);
        }
        if (!safe.child_process.execSync(`ssh-keygen -m PEM -t rsa -f "${paths.SFTP_KEYS_DIR}/ssh_host_rsa_key" -q -N ""`)) throw new BoxError(BoxError.OPENSSL_ERROR, `Could not generate sftp ssh keys: ${safe.error.message}`);
        sftpPublicKey = safe.fs.readFileSync(paths.SFTP_PUBLIC_KEY_FILE);
        await set(exports.SFTP_PUBLIC_KEY, sftpPublicKey);
        sftpPrivateKey = safe.fs.readFileSync(paths.SFTP_PRIVATE_KEY_FILE);
        await set(exports.SFTP_PRIVATE_KEY, sftpPrivateKey);
    } else if (!safe.fs.existsSync(paths.SFTP_PUBLIC_KEY_FILE) || !safe.fs.existsSync(paths.SFTP_PRIVATE_KEY_FILE)) {
        if (!safe.fs.writeFileSync(paths.SFTP_PUBLIC_KEY_FILE, sftpPublicKey)) throw new BoxError(BoxError.FS_ERROR, `Could not save sftp public key: ${safe.error.message}`);
        if (!safe.fs.writeFileSync(paths.SFTP_PRIVATE_KEY_FILE, sftpPrivateKey)) throw new BoxError(BoxError.FS_ERROR, `Could not save sftp private key: ${safe.error.message}`);
    }
}