/*
Copyright 2017-2020 Balena Ltd.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

const BOOT_PARTITION = 1;
const CONNECTIONS_FOLDER = '/system-connections';

const getConfigurationSchema = function (connnectionFileName) {
	if (connnectionFileName == null) {
		connnectionFileName = 'resin-wifi';
	}
	return {
		mapper: [
			{
				template: {
					persistentLogging: '{{persistentLogging}}',
				},
				domain: [['config_json', 'persistentLogging']],
			},
			{
				template: {
					hostname: '{{hostname}}',
				},
				domain: [['config_json', 'hostname']],
			},
			{
				template: {
					wifi: {
						ssid: '{{networkSsid}}',
					},
					'wifi-security': {
						psk: '{{networkKey}}',
					},
				},
				domain: [
					['system_connections', connnectionFileName, 'wifi'],
					['system_connections', connnectionFileName, 'wifi-security'],
				],
			},
		],
		files: {
			system_connections: {
				fileset: true,
				type: 'ini',
				location: {
					path: CONNECTIONS_FOLDER.slice(1),
					// Reconfix still uses the older resin-image-fs, so still needs an
					// object-based partition definition.
					partition: BOOT_PARTITION,
				},
			},
			config_json: {
				type: 'json',
				location: {
					path: 'config.json',
					partition: BOOT_PARTITION,
				},
			},
		},
	};
};

const inquirerOptions = (data) => [
	{
		message: 'Network SSID',
		type: 'input',
		name: 'networkSsid',
		default: data.networkSsid,
	},
	{
		message: 'Network Key',
		type: 'input',
		name: 'networkKey',
		default: data.networkKey,
	},
	{
		message: 'Do you want to set advanced settings?',
		type: 'confirm',
		name: 'advancedSettings',
		default: false,
	},
	{
		message: 'Device Hostname',
		type: 'input',
		name: 'hostname',
		default: data.hostname,
		when(answers) {
			return answers.advancedSettings;
		},
	},
	{
		message: 'Do you want to enable persistent logging?',
		type: 'confirm',
		name: 'persistentLogging',
		default: data.persistentLogging,
		when(answers) {
			return answers.advancedSettings;
		},
	},
];

const getConfiguration = function (data) {
	const _ = require('lodash');
	const inquirer = require('inquirer');

	// `persistentLogging` can be `undefined`, so we want
	// to make sure that case defaults to `false`
	data = _.assign(data, { persistentLogging: data.persistentLogging || false });

	return inquirer
		.prompt(inquirerOptions(data))
		.then((answers) => _.merge(data, answers));
};

// Taken from https://goo.gl/kr1kCt
const CONNECTION_FILE = `\
[connection]
id=resin-wifi
type=wifi

[wifi]
hidden=true
mode=infrastructure
ssid=My_Wifi_Ssid

[wifi-security]
auth-alg=open
key-mgmt=wpa-psk
psk=super_secret_wifi_password

[ipv4]
method=auto

[ipv6]
addr-gen-mode=stable-privacy
method=auto\
`;

/*
 * if the `resin-wifi` file exists (previously configured image or downloaded from the UI) it's used and reconfigured
 * if the `resin-sample.ignore` exists it's copied to `resin-wifi`
 * if the `resin-sample` exists it's reconfigured (legacy mode, will be removed eventually)
 * otherwise, the new file is created
 */
const prepareConnectionFile = function (target) {
	const _ = require('lodash');
	const imagefs = require('resin-image-fs');

	return imagefs
		.listDirectory({
			image: target,
			partition: BOOT_PARTITION,
			path: CONNECTIONS_FOLDER,
		})
		.then(function (files) {
			// The required file already exists
			if (_.includes(files, 'resin-wifi')) {
				return null;
			}

			// Fresh image, new mode, accoding to https://github.com/balena-os/meta-balena/pull/770/files
			if (_.includes(files, 'resin-sample.ignore')) {
				return imagefs
					.copy(
						{
							image: target,
							partition: BOOT_PARTITION,
							path: `${CONNECTIONS_FOLDER}/resin-sample.ignore`,
						},
						{
							image: target,
							partition: BOOT_PARTITION,
							path: `${CONNECTIONS_FOLDER}/resin-wifi`,
						},
					)
					.thenReturn(null);
			}

			// Legacy mode, to be removed later
			// We return the file name override from this branch
			// When it is removed the following cleanup should be done:
			// * delete all the null returns from this method
			// * turn `getConfigurationSchema` back into the constant, with the connection filename always being `resin-wifi`
			// * drop the final `then` from this method
			// * adapt the code in the main listener to not receive the config from this method, and use that constant instead
			if (_.includes(files, 'resin-sample')) {
				return 'resin-sample';
			}

			// In case there's no file at all (shouldn't happen normally, but the file might have been removed)
			return imagefs
				.writeFile(
					{
						image: target,
						partition: BOOT_PARTITION,
						path: `${CONNECTIONS_FOLDER}/resin-wifi`,
					},
					CONNECTION_FILE,
				)
				.thenReturn(null);
		})
		.then((connectionFileName) => getConfigurationSchema(connectionFileName));
};

const removeHostname = function (schema) {
	const _ = require('lodash');
	schema.mapper = _.reject(schema.mapper, (mapper) =>
		_.isEqual(Object.keys(mapper.template), ['hostname']),
	);
};

export const configure = {
	signature: 'local configure <target>',
	description: '(Re)configure a balenaOS drive or image',
	help: `\
Use this command to configure or reconfigure a balenaOS drive or image.

Examples:

	$ balena local configure /dev/sdc
	$ balena local configure path/to/image.img\
`,
	root: true,
	action(params) {
		const Bluebird = require('bluebird');
		const path = require('path');
		const umount = require('umount');
		const umountAsync = Bluebird.promisify(umount.umount);
		const isMountedAsync = Bluebird.promisify(umount.isMounted);
		const reconfix = require('reconfix');
		const denymount = Bluebird.promisify(require('denymount'));

		return prepareConnectionFile(params.target)
			.tap(() =>
				isMountedAsync(params.target).then(function (isMounted) {
					if (!isMounted) {
						return;
					}
					return umountAsync(params.target);
				}),
			)
			.then(function (configurationSchema) {
				const dmOpts = {};
				if (process.pkg) {
					// when running in a standalone pkg install, the 'denymount'
					// executable is placed on the same folder as process.execPath
					dmOpts.executablePath = path.join(
						path.dirname(process.execPath),
						'denymount',
					);
				}
				const dmHandler = (cb) =>
					reconfix
						.readConfiguration(configurationSchema, params.target)
						.then(getConfiguration)
						.then(function (answers) {
							if (!answers.hostname) {
								removeHostname(configurationSchema);
							}
							return reconfix.writeConfiguration(
								configurationSchema,
								answers,
								params.target,
							);
						})
						.asCallback(cb);
				return denymount(params.target, dmHandler, dmOpts);
			})
			.then(() => {
				console.log('Done!');
			});
	},
};