'use strict';

exports = module.exports = {
    reboot,
    getInfo,
    getMemory,
    getLogs,
    getLogStream,
    getMetrics,
    getMetricStream,
    getBlockDevices,
    getFilesystems,
    getFilesystemUsage,
    getCpus,
};

const assert = require('node:assert'),
    BoxError = require('../boxerror.js'),
    HttpError = require('@cloudron/connect-lastmile').HttpError,
    HttpSuccess = require('@cloudron/connect-lastmile').HttpSuccess,
    metrics = require('../metrics.js'),
    safe = require('safetydance'),
    system = require('../system.js');

async function reboot(req, res, next) {
    // Finish the request, to let the appstore know we triggered the reboot
    next(new HttpSuccess(202, {}));

    await safe(system.reboot());
}

async function getInfo(req, res, next) {
    const [error, info] = await safe(system.getInfo());
    if (error) return next(BoxError.toHttpError(error));

    next(new HttpSuccess(200, { info }));
}

async function getMemory(req, res, next) {
    const [error, result] = await safe(system.getMemory());
    if (error) return next(BoxError.toHttpError(error));

    next(new HttpSuccess(200, result));
}

async function getLogs(req, res, next) {
    assert.strictEqual(typeof req.params.unit, 'string');

    const lines = typeof req.query.lines === 'string' ? parseInt(req.query.lines, 10) : 10; // we ignore last-event-id
    if (isNaN(lines)) return next(new HttpError(400, 'lines must be a number'));

    const options = {
        lines: lines,
        follow: false,
        format: typeof req.query.format === 'string' ? req.query.format : 'json'
    };

    const [error, logStream] = await safe(system.getLogs(req.params.unit, options));
    if (error) return next(BoxError.toHttpError(error));

    res.writeHead(200, {
        'Content-Type': 'application/x-logs',
        'Content-Disposition': `attachment; filename="${req.params.unit}.log"`,
        'Cache-Control': 'no-cache',
        'X-Accel-Buffering': 'no' // disable nginx buffering
    });
    res.on('close', () => logStream.destroy());
    logStream.pipe(res);
}

async function getLogStream(req, res, next) {
    assert.strictEqual(typeof req.params.unit, 'string');

    const lines = typeof req.query.lines === 'string' ? parseInt(req.query.lines, 10) : 10; // we ignore last-event-id
    if (isNaN(lines)) return next(new HttpError(400, 'lines must be a valid number'));

    function sse(id, data) { return 'id: ' + id + '\ndata: ' + data + '\n\n'; }

    if (req.headers.accept !== 'text/event-stream') return next(new HttpError(400, 'This API call requires EventStream'));

    const options = {
        lines: lines,
        follow: true,
        format: typeof req.query.format === 'string' ? req.query.format : 'json'
    };

    const [error, logStream] = await safe(system.getLogs(req.params.unit, options));
    if (error) return next(BoxError.toHttpError(error));

    res.writeHead(200, {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive',
        'X-Accel-Buffering': 'no', // disable nginx buffering
        'Access-Control-Allow-Origin': '*'
    });
    res.write('retry: 3000\n');
    res.on('close', () => logStream.destroy());
    logStream.on('data', function (data) {
        const obj = JSON.parse(data);
        res.write(sse(obj.realtimeTimestamp, JSON.stringify(obj))); // send timestamp as id
    });
    logStream.on('end', res.end.bind(res));
    logStream.on('error', res.end.bind(res, null));
}

async function getMetrics(req, res, next) {
    if (typeof req.query.fromSecs !== 'string' || !parseInt(req.query.fromSecs, 10)) return next(new HttpError(400, 'fromSecs must be a number'));
    if (typeof req.query.intervalSecs !== 'string' || !parseInt(req.query.intervalSecs, 10)) return next(new HttpError(400, 'intervalSecs must be a number'));

    const fromSecs = parseInt(req.query.fromSecs, 10);
    const intervalSecs = parseInt(req.query.intervalSecs, 10);
    const noNullPoints = typeof req.query.noNullPoints === 'string' ? (req.query.noNullPoints === '1' || req.query.noNullPoints === 'true') : false;
    const system = req.query.system === 'true';
    const appIds = 'appId' in req.query ? (Array.isArray(req.query.appId) ? req.query.appId : [ req.query.appId ]) : [];
    const serviceIds = 'serviceId' in req.query ? (Array.isArray(req.query.serviceId) ? req.query.serviceId : [ req.query.serviceId ]) : [];

    const [error, result] = await safe(metrics.get({ fromSecs, intervalSecs, noNullPoints, system, appIds, serviceIds }));
    if (error) return next(new HttpError(500, error));

    next(new HttpSuccess(200, result));
}

async function getMetricStream(req, res, next) {
    if (req.headers.accept !== 'text/event-stream') return next(new HttpError(400, 'This API call requires EventStream'));

    const system = req.query.system === 'true';
    const appIds = 'appId' in req.query ? (Array.isArray(req.query.appId) ? req.query.appId : [ req.query.appId ]) : [];
    const serviceIds = 'serviceId' in req.query ? (Array.isArray(req.query.serviceId) ? req.query.serviceId : [ req.query.serviceId ]) : [];

    const [error, metricStream] = await safe(metrics.getStream({ system, appIds, serviceIds }));
    if (error) return next(BoxError.toHttpError(error));

    res.writeHead(200, {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive',
        'X-Accel-Buffering': 'no', // disable nginx buffering
        'Access-Control-Allow-Origin': '*'
    });
    res.write('retry: 3000\n');
    res.on('close', () => metricStream.destroy());
    metricStream.on('data', function (obj) { // objectMode stream
        const sse = `data: ${JSON.stringify(obj)}\n\n`;
        res.write(sse);
    });
    metricStream.on('end', res.end.bind(res));
    metricStream.on('error', res.end.bind(res, null));
}

async function getBlockDevices(req, res, next) {
    const [error, devices] = await safe(system.getBlockDevices());
    if (error) return next(new HttpError(500, error));

    next(new HttpSuccess(200, { devices }));
}

async function getCpus(req, res, next) {
    const [error, cpus] = await safe(system.getCpus());
    if (error) return next(BoxError.toHttpError(error));

    next(new HttpSuccess(200, { cpus }));
}

async function getFilesystems(req, res, next) {
    const [error, filesystems] = await safe(system.getFilesystems());
    if (error) return next(new HttpError(500, error));

    next(new HttpSuccess(200, { filesystems }));
}

async function getFilesystemUsage(req, res, next) {
    if (typeof req.query.filesystem !== 'string') return next(new HttpError(400, 'getFilesystemUsage'));
    if (req.headers.accept !== 'text/event-stream') return next(new HttpError(400, 'This API call requires EventStream'));

    const [error, task] = await safe(system.getFilesystemUsage(req.query.filesystem));
    if (error) return next(BoxError.toHttpError(error));

    res.writeHead(200, {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive',
        'X-Accel-Buffering': 'no', // disable nginx buffering
        'Access-Control-Allow-Origin': '*'
    });
    res.write('retry: 30000\n'); // client should .close() to prevent reconnect within 30s
    res.on('close', () => task.stop());
    task.on('data', function (type, data) {
        const obj = { type, ...data };
        const sse = `data: ${JSON.stringify(obj)}\n\n`;
        res.write(sse);
    });
    task.on('done', function (error) {
        const obj = { type: 'done', ...error };
        const sse = `data: ${JSON.stringify(obj)}\n\n`;
        res.write(sse);
        res.end();
    });

    task.start(); // background
}