/**
 * @license
 * Copyright 2016-2020 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.
 */

import { flags } from '@oclif/command';
import Command from '../../command';
import * as cf from '../../utils/common-flags';
import { getBalenaSdk, getCliForm, stripIndent } from '../../utils/lazy';
import {
	applicationIdInfo,
	appToFleetFlagMsg,
	warnify,
} from '../../utils/messages';
import { isV13 } from '../../utils/version';
import type { PineDeferred } from 'balena-sdk';

interface FlagsDef {
	version: string; // OS version
	application?: string;
	app?: string; // application alias
	fleet?: string;
	device?: string;
	deviceApiKey?: string;
	deviceType?: string;
	'generate-device-api-key': boolean;
	output?: string;
	// Options for non-interactive configuration
	network?: string;
	wifiSsid?: string;
	wifiKey?: string;
	appUpdatePollInterval?: string;
	help: void;
}

export default class ConfigGenerateCmd extends Command {
	public static description = stripIndent`
		Generate a config.json file.

		Generate a config.json file for a device or fleet.

		The target balenaOS version must be specified with the --version option.

		To configure an image for a fleet of mixed device types, use the --fleet option
		alongside the --deviceType option to specify the target device type.

		To avoid interactive questions, specify a command line option for each question that
		would otherwise be asked.

		${applicationIdInfo.split('\n').join('\n\t\t')}
	`;

	public static examples = [
		'$ balena config generate --device 7cf02a6 --version 2.12.7',
		'$ balena config generate --device 7cf02a6 --version 2.12.7 --generate-device-api-key',
		'$ balena config generate --device 7cf02a6 --version 2.12.7 --device-api-key <existingDeviceKey>',
		'$ balena config generate --device 7cf02a6 --version 2.12.7 --output config.json',
		'$ balena config generate --fleet MyFleet --version 2.12.7',
		'$ balena config generate --fleet myorg/myfleet --version 2.12.7',
		'$ balena config generate --fleet MyFleet --version 2.12.7 --deviceType fincm3',
		'$ balena config generate --fleet MyFleet --version 2.12.7 --output config.json',
		'$ balena config generate --fleet MyFleet --version 2.12.7 --network wifi --wifiSsid mySsid --wifiKey abcdefgh --appUpdatePollInterval 15',
	];

	public static usage = 'config generate';

	public static flags: flags.Input<FlagsDef> = {
		version: flags.string({
			description: 'a balenaOS version',
			required: true,
		}),
		...(isV13()
			? {}
			: {
					application: {
						...cf.application,
						exclusive: ['app', 'fleet', 'device'],
					},
					app: { ...cf.app, exclusive: ['application', 'fleet', 'device'] },
					appUpdatePollInterval: flags.string({
						description: 'DEPRECATED alias for --updatePollInterval',
					}),
			  }),
		fleet: { ...cf.fleet, exclusive: ['application', 'app', 'device'] },
		device: { ...cf.device, exclusive: ['application', 'app', 'fleet'] },
		deviceApiKey: flags.string({
			description:
				'custom device key - note that this is only supported on balenaOS 2.0.3+',
			char: 'k',
		}),
		deviceType: flags.string({
			description:
				"device type slug (run 'balena devices supported' for possible values)",
		}),
		'generate-device-api-key': flags.boolean({
			description: 'generate a fresh device key for the device',
		}),
		output: flags.string({
			description: 'path of output file',
			char: 'o',
		}),
		// Options for non-interactive configuration
		network: flags.string({
			description: 'the network type to use: ethernet or wifi',
			options: ['ethernet', 'wifi'],
		}),
		wifiSsid: flags.string({
			description:
				'the wifi ssid to use (used only if --network is set to wifi)',
		}),
		wifiKey: flags.string({
			description:
				'the wifi key to use (used only if --network is set to wifi)',
		}),
		appUpdatePollInterval: flags.string({
			description:
				'supervisor cloud polling interval in minutes (e.g. for variable updates)',
		}),
		help: cf.help,
	};

	public static authenticated = true;

	public async run() {
		const { flags: options } = this.parse<FlagsDef, {}>(ConfigGenerateCmd);

		const { getApplication } = await import('../../utils/sdk');

		const balena = getBalenaSdk();

		await this.validateOptions(options);

		let resourceDeviceType: string;
		let application: ApplicationWithDeviceType | null = null;
		let device:
			| (DeviceWithDeviceType & { belongs_to__application: PineDeferred })
			| null = null;
		if (options.device != null) {
			const { tryAsInteger } = await import('../../utils/validation');
			const rawDevice = await balena.models.device.get(
				tryAsInteger(options.device),
				{ $expand: { is_of__device_type: { $select: 'slug' } } },
			);
			if (!rawDevice.belongs_to__application) {
				const { ExpectedError } = await import('../../errors');
				throw new ExpectedError(stripIndent`
					Device ${options.device} does not appear to belong to an accessible fleet.
					Try with a different device, or use '--fleet' instead of '--device'.`);
			}
			device = rawDevice as DeviceWithDeviceType & {
				belongs_to__application: PineDeferred;
			};
			resourceDeviceType = device.is_of__device_type[0].slug;
		} else {
			// Disambiguate application (if is a number, it could either be an ID or a numerical name)
			application = (await getApplication(balena, options.application!, {
				$expand: {
					is_for__device_type: { $select: 'slug' },
				},
			})) as ApplicationWithDeviceType;
			resourceDeviceType = application.is_for__device_type[0].slug;
		}

		const deviceType = options.deviceType || resourceDeviceType;

		const deviceManifest = await balena.models.device.getManifestBySlug(
			deviceType,
		);

		// Check compatibility if application and deviceType provided
		if (options.application && options.deviceType) {
			const appDeviceManifest = await balena.models.device.getManifestBySlug(
				resourceDeviceType,
			);

			const helpers = await import('../../utils/helpers');
			if (
				!helpers.areDeviceTypesCompatible(appDeviceManifest, deviceManifest)
			) {
				throw new balena.errors.BalenaInvalidDeviceType(
					`Device type ${options.deviceType} is incompatible with fleet ${options.application}`,
				);
			}
		}

		// Prompt for values
		// Pass params as an override: if there is any param with exactly the same name as a
		// required option, that value is used (and the corresponding question is not asked)
		const answers = await getCliForm().run(deviceManifest.options, {
			override: options,
		});
		answers.version = options.version;

		// Generate config
		const { generateDeviceConfig, generateApplicationConfig } = await import(
			'../../utils/config'
		);

		let config;
		if (device) {
			config = await generateDeviceConfig(
				device,
				options.deviceApiKey || options['generate-device-api-key'] || undefined,
				answers,
			);
		} else if (application) {
			answers.deviceType = deviceType;
			config = await generateApplicationConfig(application, answers);
		}

		// Output
		if (options.output != null) {
			const fs = await import('fs');
			await fs.promises.writeFile(options.output, JSON.stringify(config));
		}

		const prettyjson = await import('prettyjson');
		console.log(prettyjson.render(config));
	}

	protected readonly missingDeviceOrAppMessage = stripIndent`
		Either a device or a fleet must be specified.

		See the help page for examples:

		  $ balena help config generate
  	`;

	protected readonly deviceTypeNotAllowedMessage =
		'The --deviceType option can only be used alongside the --fleet option';

	protected async validateOptions(options: FlagsDef) {
		const { ExpectedError } = await import('../../errors');

		if ((options.application || options.app) && process.stderr.isTTY) {
			console.error(warnify(appToFleetFlagMsg));
		}
		options.application ||= options.app || options.fleet;
		// Prefer options.application over options.app
		delete options.app;

		if (options.device == null && options.application == null) {
			throw new ExpectedError(this.missingDeviceOrAppMessage);
		}

		if (!options.application && options.deviceType) {
			throw new ExpectedError(this.deviceTypeNotAllowedMessage);
		}
	}
}