'use strict';

exports = module.exports = {
    testRegistryConfig: testRegistryConfig,
    setRegistryConfig: setRegistryConfig,
    injectPrivateFields: injectPrivateFields,
    removePrivateFields: removePrivateFields,

    SECRET_PLACEHOLDER: String.fromCharCode(0x25CF).repeat(8),

    ping: ping,

    info: info,
    downloadImage: downloadImage,
    createContainer: createContainer,
    startContainer: startContainer,
    restartContainer: restartContainer,
    stopContainer: stopContainer,
    stopContainerByName: stopContainer,
    stopContainers: stopContainers,
    deleteContainer: deleteContainer,
    deleteContainerByName: deleteContainer,
    deleteImage: deleteImage,
    deleteContainers: deleteContainers,
    createSubcontainer: createSubcontainer,
    getContainerIdByIp: getContainerIdByIp,
    inspect: inspect,
    inspectByName: inspect,
    execContainer: execContainer,
    getEvents: getEvents,
    memoryUsage: memoryUsage,
    createVolume: createVolume,
    removeVolume: removeVolume,
    clearVolume: clearVolume
};

var addons = require('./addons.js'),
    async = require('async'),
    assert = require('assert'),
    BoxError = require('./boxerror.js'),
    child_process = require('child_process'),
    constants = require('./constants.js'),
    debug = require('debug')('box:docker'),
    Docker = require('dockerode'),
    path = require('path'),
    settings = require('./settings.js'),
    shell = require('./shell.js'),
    safe = require('safetydance'),
    util = require('util'),
    _ = require('underscore');

const CLEARVOLUME_CMD = path.join(__dirname, 'scripts/clearvolume.sh'),
    MKDIRVOLUME_CMD = path.join(__dirname, 'scripts/mkdirvolume.sh');

const DOCKER_SOCKET_PATH = '/var/run/docker.sock';
const gConnection = new Docker({ socketPath: DOCKER_SOCKET_PATH });

function debugApp(app) {
    assert(typeof app === 'object');

    debug(app.fqdn + ' ' + util.format.apply(util, Array.prototype.slice.call(arguments, 1)));
}

function testRegistryConfig(auth, callback) {
    assert.strictEqual(typeof auth, 'object');
    assert.strictEqual(typeof callback, 'function');

    gConnection.checkAuth(auth, function (error /*, data */) { // this returns a 500 even for auth errors
        if (error) return callback(new BoxError(BoxError.BAD_FIELD, error, { field: 'serverAddress' }));

        callback();
    });
}

function injectPrivateFields(newConfig, currentConfig) {
    if (newConfig.password === exports.SECRET_PLACEHOLDER) newConfig.password = currentConfig.password;
}

function removePrivateFields(registryConfig) {
    assert.strictEqual(typeof registryConfig, 'object');

    if (registryConfig.password) registryConfig.password = exports.SECRET_PLACEHOLDER;

    return registryConfig;
}

function setRegistryConfig(auth, callback) {
    assert.strictEqual(typeof auth, 'object');
    assert.strictEqual(typeof callback, 'function');

    const isLogin = !!auth.password;

    // currently, auth info is not stashed in the db but maybe it should for restore to work?
    const cmd = isLogin ? `docker login ${auth.serverAddress} --username ${auth.username} --password ${auth.password}` : `docker logout ${auth.serverAddress}`;

    child_process.exec(cmd, { }, function (error /*, stdout, stderr */) {
        if (error) return callback(new BoxError(BoxError.ACCESS_DENIED, error.message));

        callback();
    });
}

function ping(callback) {
    assert.strictEqual(typeof callback, 'function');

    // do not let the request linger
    const connection = new Docker({ socketPath: DOCKER_SOCKET_PATH, timeout: 1000 });

    connection.ping(function (error, result) {
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));
        if (result !== 'OK') return callback(new BoxError(BoxError.DOCKER_ERROR, 'Unable to ping the docker daemon'));

        callback(null);
    });
}

function getRegistryConfig(image, callback) {
    // https://github.com/docker/distribution/blob/release/2.7/reference/normalize.go#L62
    const parts = image.split('/');
    if (parts.length === 1 || (parts[0].match(/[.:]/) === null)) return callback(null, null); // public docker registry

    settings.getRegistryConfig(function (error, registryConfig) {
        if (error) return callback(error);

        // https://github.com/apocas/dockerode#pull-from-private-repos
        const auth = {
            username: registryConfig.username,
            password: registryConfig.password,
            auth: registryConfig.auth || '', // the auth token at login time
            email: registryConfig.email || '',
            serveraddress: registryConfig.serverAddress
        };

        callback(null, auth);
    });
}

function pullImage(manifest, callback) {
    getRegistryConfig(manifest.dockerImage, function (error, authConfig) {
        if (error) return callback(error);

        debug(`pullImage: will pull ${manifest.dockerImage}. auth: ${authConfig ? 'yes' : 'no'}`);

        gConnection.pull(manifest.dockerImage, { authconfig: authConfig }, function (error, stream) {
            if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, 'Unable to pull image. Please check the network or if the image needs authentication. statusCode: ' + error.statusCode));

            // https://github.com/dotcloud/docker/issues/1074 says each status message
            // is emitted as a chunk
            stream.on('data', function (chunk) {
                var data = safe.JSON.parse(chunk) || { };
                debug('pullImage: %j', data);

                // The data.status here is useless because this is per layer as opposed to per image
                if (!data.status && data.error) {
                    debug('pullImage error %s: %s', manifest.dockerImage, data.errorDetail.message);
                }
            });

            stream.on('end', function () {
                debug('downloaded image %s', manifest.dockerImage);

                callback(null);
            });

            stream.on('error', function (error) {
                debug('error pulling image %s: %j', manifest.dockerImage, error);

                callback(new BoxError(BoxError.DOCKER_ERROR, error.message));
            });
        });
    });
}

function downloadImage(manifest, callback) {
    assert.strictEqual(typeof manifest, 'object');
    assert.strictEqual(typeof callback, 'function');

    debug('downloadImage %s', manifest.dockerImage);

    var attempt = 1;

    async.retry({ times: 10, interval: 15000 }, function (retryCallback) {
        debug('Downloading image %s. attempt: %s', manifest.dockerImage, attempt++);

        pullImage(manifest, function (error) {
            if (error) console.error(error);

            retryCallback(error);
        });
    }, callback);
}

function createSubcontainer(app, name, cmd, options, callback) {
    assert.strictEqual(typeof app, 'object');
    assert.strictEqual(typeof name, 'string');
    assert(!cmd || util.isArray(cmd));
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof callback, 'function');

    let isAppContainer = !cmd; // non app-containers are like scheduler and exec (terminal) containers

    var manifest = app.manifest;
    var exposedPorts = {}, dockerPortBindings = { };
    var domain = app.fqdn;
    const hostname = isAppContainer ? app.id : name;

    const envPrefix = manifest.manifestVersion <= 1 ? '' : 'CLOUDRON_';

    let stdEnv = [
        'CLOUDRON=1',
        'CLOUDRON_PROXY_IP=172.18.0.1',
        `CLOUDRON_APP_HOSTNAME=${app.id}`,
        `${envPrefix}WEBADMIN_ORIGIN=${settings.adminOrigin()}`,
        `${envPrefix}API_ORIGIN=${settings.adminOrigin()}`,
        `${envPrefix}APP_ORIGIN=https://${domain}`,
        `${envPrefix}APP_DOMAIN=${domain}`
    ];

    // docker portBindings requires ports to be exposed
    exposedPorts[manifest.httpPort + '/tcp'] = {};

    dockerPortBindings[manifest.httpPort + '/tcp'] = [ { HostIp: '127.0.0.1', HostPort: app.httpPort + '' } ];

    var portEnv = [];
    for (let portName in app.portBindings) {
        const hostPort = app.portBindings[portName];
        const portType = (manifest.tcpPorts && portName in manifest.tcpPorts) ? 'tcp' : 'udp';
        const ports = portType == 'tcp' ? manifest.tcpPorts : manifest.udpPorts;

        var containerPort = ports[portName].containerPort || hostPort;

        exposedPorts[`${containerPort}/${portType}`] = {};
        portEnv.push(`${portName}=${hostPort}`);

        dockerPortBindings[`${containerPort}/${portType}`] = [ { HostIp: '0.0.0.0', HostPort: hostPort + '' } ];
    }

    let appEnv = [];
    Object.keys(app.env).forEach(function (name) { appEnv.push(`${name}=${app.env[name]}`); });

    // first check db record, then manifest
    var memoryLimit = app.memoryLimit || manifest.memoryLimit || 0;

    if (memoryLimit === -1) { // unrestricted
        memoryLimit = 0;
    } else if (memoryLimit === 0 || memoryLimit < constants.DEFAULT_MEMORY_LIMIT) { // ensure we never go below minimum (in case we change the default)
        memoryLimit = constants.DEFAULT_MEMORY_LIMIT;
    }

    // give scheduler tasks twice the memory limit since background jobs take more memory
    // if required, we can make this a manifest and runtime argument later
    if (!isAppContainer) memoryLimit *= 2;

    addons.getEnvironment(app, function (error, addonEnv) {
        if (error) return callback(error);

        // do no set hostname of containers to location as it might conflict with addons names. for example, an app installed in mail
        // location may not reach mail container anymore by DNS. We cannot set hostname to fqdn either as that sets up the dns
        // name to look up the internal docker ip. this makes curl from within container fail
        // Note that Hostname has no effect on DNS. We have to use the --net-alias for dns.
        // Hostname cannot be set with container NetworkMode
        var containerOptions = {
            name: name, // for referencing containers
            Tty: isAppContainer,
            Hostname: hostname,
            Image: app.manifest.dockerImage,
            Cmd: (isAppContainer && app.debugMode && app.debugMode.cmd) ? app.debugMode.cmd : cmd,
            Env: stdEnv.concat(addonEnv).concat(portEnv).concat(appEnv),
            ExposedPorts: isAppContainer ? exposedPorts : { },
            Volumes: { // see also ReadonlyRootfs
                '/tmp': {},
                '/run': {}
            },
            Labels: {
                'fqdn': app.fqdn,
                'appId': app.id,
                'isSubcontainer': String(!isAppContainer),
                'isCloudronManaged': String(true)
            },
            HostConfig: {
                Mounts: addons.getMountsSync(app, app.manifest.addons),
                LogConfig: {
                    Type: 'syslog',
                    Config: {
                        'tag': app.id,
                        'syslog-address': 'udp://127.0.0.1:2514', // see apps.js:validatePortBindings()
                        'syslog-format': 'rfc5424'
                    }
                },
                Memory: memoryLimit / 2,
                MemorySwap: memoryLimit, // Memory + Swap
                PortBindings: isAppContainer ? dockerPortBindings : { },
                PublishAllPorts: false,
                ReadonlyRootfs: app.debugMode ? !!app.debugMode.readonlyRootfs : true,
                RestartPolicy: {
                    'Name': isAppContainer ? 'unless-stopped' : 'no',
                    'MaximumRetryCount': 0
                },
                CpuShares: 512, // relative to 1024 for system processes
                VolumesFrom: isAppContainer ? null : [ app.containerId + ':rw' ],
                NetworkMode: 'cloudron', // user defined bridge network
                Dns: ['172.18.0.1'], // use internal dns
                DnsSearch: ['.'], // use internal dns
                SecurityOpt: [ 'apparmor=docker-cloudron-app' ]
            },
            NetworkingConfig: {
                EndpointsConfig: {
                    cloudron: {
                        Aliases: [ name ] // this allows sub-containers reach app containers by name
                    }
                }
            }
        };

        var capabilities = manifest.capabilities || [];
        if (capabilities.includes('net_admin')) {
            containerOptions.HostConfig.CapAdd = [
                'NET_ADMIN'
            ];
        }

        containerOptions = _.extend(containerOptions, options);

        debugApp(app, 'Creating container for %s', app.manifest.dockerImage);

        gConnection.createContainer(containerOptions, function (error, container) {
            if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

            callback(null, container);
        });
    });
}

function createContainer(app, callback) {
    createSubcontainer(app, app.id /* name */, null /* cmd */, { } /* options */, callback);
}

function startContainer(containerId, callback) {
    assert.strictEqual(typeof containerId, 'string');
    assert.strictEqual(typeof callback, 'function');

    var container = gConnection.getContainer(containerId);
    debug('Starting container %s', containerId);

    container.start(function (error) {
        if (error && error.statusCode === 404) return callback(new BoxError(BoxError.NOT_FOUND));
        if (error && error.statusCode === 400) return callback(new BoxError(BoxError.BAD_FIELD, error)); // e.g start.sh is not executable
        if (error && error.statusCode !== 304) return callback(new BoxError(BoxError.DOCKER_ERROR, error)); // 304 means already started

        return callback(null);
    });
}

function restartContainer(containerId, callback) {
    assert.strictEqual(typeof containerId, 'string');
    assert.strictEqual(typeof callback, 'function');

    var container = gConnection.getContainer(containerId);
    debug('Restarting container %s', containerId);

    container.restart(function (error) {
        if (error && error.statusCode === 404) return callback(new BoxError(BoxError.NOT_FOUND));
        if (error && error.statusCode === 400) return callback(new BoxError(BoxError.BAD_FIELD, error)); // e.g start.sh is not executable
        if (error && error.statusCode !== 204) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        return callback(null);
    });
}

function stopContainer(containerId, callback) {
    assert(!containerId || typeof containerId === 'string');
    assert.strictEqual(typeof callback, 'function');

    if (!containerId) {
        debug('No previous container to stop');
        return callback();
    }

    var container = gConnection.getContainer(containerId);
    debug('Stopping container %s', containerId);

    var options = {
        t: 10 // wait for 10 seconds before killing it
    };

    container.stop(options, function (error) {
        if (error && (error.statusCode !== 304 && error.statusCode !== 404)) return callback(new BoxError(BoxError.DOCKER_ERROR, 'Error stopping container:' + error.message));

        debug('Waiting for container ' + containerId);

        container.wait(function (error, data) {
            if (error && (error.statusCode !== 304 && error.statusCode !== 404)) return callback(new BoxError(BoxError.DOCKER_ERROR, 'Error waiting on container:' + error.message));

            debug('Container %s stopped with status code [%s]', containerId, data ? String(data.StatusCode) : '');

            return callback(null);
        });
    });
}

function deleteContainer(containerId, callback) {
    assert(!containerId || typeof containerId === 'string');
    assert.strictEqual(typeof callback, 'function');

    debug('deleting container %s', containerId);

    if (containerId === null) return callback(null);

    var container = gConnection.getContainer(containerId);

    var removeOptions = {
        force: true, // kill container if it's running
        v: true // removes volumes associated with the container (but not host mounts)
    };

    container.remove(removeOptions, function (error) {
        if (error && error.statusCode === 404) return callback(null);

        if (error) {
            debug('Error removing container %s : %j', containerId, error);
            return callback(new BoxError(BoxError.DOCKER_ERROR, error));
        }

        callback(null);
    });
}

function deleteContainers(appId, options, callback) {
    assert.strictEqual(typeof appId, 'string');
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof callback, 'function');

    debug('deleting containers of %s', appId);

    let labels = [ 'appId=' + appId ];
    if (options.managedOnly) labels.push('isCloudronManaged=true');

    gConnection.listContainers({ all: 1, filters: JSON.stringify({ label: labels }) }, function (error, containers) {
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        async.eachSeries(containers, function (container, iteratorDone) {
            deleteContainer(container.Id, iteratorDone);
        }, callback);
    });
}

function stopContainers(appId, callback) {
    assert.strictEqual(typeof appId, 'string');
    assert.strictEqual(typeof callback, 'function');

    debug('stopping containers of %s', appId);

    gConnection.listContainers({ all: 1, filters: JSON.stringify({ label: [ 'appId=' + appId ] }) }, function (error, containers) {
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        async.eachSeries(containers, function (container, iteratorDone) {
            stopContainer(container.Id, iteratorDone);
        }, callback);
    });
}

function deleteImage(manifest, callback) {
    assert(!manifest || typeof manifest === 'object');
    assert.strictEqual(typeof callback, 'function');

    var dockerImage = manifest ? manifest.dockerImage : null;
    if (!dockerImage) return callback(null);

    var removeOptions = {
        force: false, // might be shared with another instance of this app
        noprune: false // delete untagged parents
    };

    // registry v1 used to pull down all *tags*. this meant that deleting image by tag was not enough (since that
    // just removes the tag). we used to remove the image by id. this is not required anymore because aliases are
    // not created anymore after https://github.com/docker/docker/pull/10571
    gConnection.getImage(dockerImage).remove(removeOptions, function (error) {
        if (error && error.statusCode === 400) return callback(null); // invalid image format. this can happen if user installed with a bad --docker-image
        if (error && error.statusCode === 404) return callback(null); // not found
        if (error && error.statusCode === 409) return callback(null); // another container using the image

        if (error) {
            debug('Error removing image %s : %j', dockerImage, error);
            return callback(new BoxError(BoxError.DOCKER_ERROR, error));
        }

        callback(null);
    });
}

function getContainerIdByIp(ip, callback) {
    assert.strictEqual(typeof ip, 'string');
    assert.strictEqual(typeof callback, 'function');

    gConnection.getNetwork('cloudron').inspect(function (error, bridge) {
        if (error && error.statusCode === 404) return callback(new BoxError(BoxError.DOCKER_ERROR, 'Unable to find the cloudron network'));
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        var containerId;
        for (var id in bridge.Containers) {
            if (bridge.Containers[id].IPv4Address.indexOf(ip + '/16') === 0) {
                containerId = id;
                break;
            }
        }
        if (!containerId) return callback(new BoxError(BoxError.DOCKER_ERROR, 'No container with that ip'));

        callback(null, containerId);
    });
}

function inspect(containerId, callback) {
    assert.strictEqual(typeof containerId, 'string');
    assert.strictEqual(typeof callback, 'function');

    var container = gConnection.getContainer(containerId);

    container.inspect(function (error, result) {
        if (error && error.statusCode === 404) return callback(new BoxError(BoxError.NOT_FOUND));
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        callback(null, result);
    });
}

function execContainer(containerId, options, callback) {
    assert.strictEqual(typeof containerId, 'string');
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof callback, 'function');

    var container = gConnection.getContainer(containerId);

    container.exec(options.execOptions, function (error, exec) {
        if (error && error.statusCode === 409) return callback(new BoxError(BoxError.BAD_STATE, error.message)); // container restarting/not running
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        exec.start(options.startOptions, function(error, stream /* in hijacked mode, this is a net.socket */) {
            if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

            if (options.rows && options.columns) {
                // there is a race where resizing too early results in a 404 "no such exec"
                // https://git.cloudron.io/cloudron/box/issues/549
                setTimeout(function () {
                    exec.resize({ h: options.rows, w: options.columns }, function (error) { if (error) debug('Error resizing console', error); });
                }, 2000);
            }

            callback(null, stream);
        });
    });
}

function getEvents(options, callback) {
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof callback, 'function');

    gConnection.getEvents(options, function (error, stream) {
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        callback(null, stream);
    });
}

function memoryUsage(containerId, callback) {
    assert.strictEqual(typeof containerId, 'string');
    assert.strictEqual(typeof callback, 'function');

    var container = gConnection.getContainer(containerId);

    container.stats({ stream: false }, function (error, result) {
        if (error && error.statusCode === 404) return callback(new BoxError(BoxError.NOT_FOUND));
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        callback(null, result);
    });
}

function createVolume(app, name, volumeDataDir, callback) {
    assert.strictEqual(typeof app, 'object');
    assert.strictEqual(typeof name, 'string');
    assert.strictEqual(typeof volumeDataDir, 'string');
    assert.strictEqual(typeof callback, 'function');

    const volumeOptions = {
        Name: name,
        Driver: 'local',
        DriverOpts: { // https://github.com/moby/moby/issues/19990#issuecomment-248955005
            type: 'none',
            device: volumeDataDir,
            o: 'bind'
        },
        Labels: {
            'fqdn': app.fqdn,
            'appId': app.id
        },
    };

    // requires sudo because the path can be outside appsdata
    shell.sudo('createVolume', [ MKDIRVOLUME_CMD, volumeDataDir ], {}, function (error) {
        if (error) return callback(new BoxError(BoxError.FS_ERROR, `Error creating app data dir: ${error.message}`));

        gConnection.createVolume(volumeOptions, function (error) {
            if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

            callback();
        });
    });
}

function clearVolume(app, name, options, callback) {
    assert.strictEqual(typeof app, 'object');
    assert.strictEqual(typeof name, 'string');
    assert.strictEqual(typeof options, 'object');
    assert.strictEqual(typeof callback, 'function');

    let volume = gConnection.getVolume(name);
    volume.inspect(function (error, v) {
        if (error && error.statusCode === 404) return callback();
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, error));

        const volumeDataDir = v.Options.device;
        shell.sudo('clearVolume', [ CLEARVOLUME_CMD, options.removeDirectory ? 'rmdir' : 'clear', volumeDataDir ], {}, function (error) {
            if (error) return callback(new BoxError(BoxError.FS_ERROR, error));

            callback();
        });
    });
}

// this only removes the volume and not the data
function removeVolume(app, name, callback) {
    assert.strictEqual(typeof app, 'object');
    assert.strictEqual(typeof name, 'string');
    assert.strictEqual(typeof callback, 'function');

    let volume = gConnection.getVolume(name);
    volume.remove(function (error) {
        if (error && error.statusCode !== 404) return callback(new BoxError(BoxError.DOCKER_ERROR, `removeVolume: Error removing volume of ${app.id} ${error.message}`));

        callback();
    });
}

function info(callback) {
    assert.strictEqual(typeof callback, 'function');

    gConnection.info(function (error, result) {
        if (error) return callback(new BoxError(BoxError.DOCKER_ERROR, 'Error connecting to docker'));

        callback(null, result);
    });
}