'use strict';

const Promise = require("bluebird");

const lsblk = require("../wrappers/lsblk");
const smartctl = require("../wrappers/smartctl");
const lvm = require("../wrappers/lvm");
const {B} = require("../units/bytes/iec");

/* FIXME: Move this to GraphQL API */
function getSmartStatus(smartData) {
	let failed = smartData.filter((item) => {
		return (item.failingNow === true || item.failedBefore === true);
	});

	let deteriorating = smartData.filter((item) => {
		return (item.type === "preFail" && item.worstValueSeen < 100);
	});

	if (failed.length > 0) {
		return "failed";
	} else if (deteriorating.length > 0) {
		return "deteriorating";
	} else {
		return "healthy";
	}
}

function getStorageDevices() {
	return Promise.try(() => {
		return lsblk();
	}).filter((device) => {
		return (device.type === "disk");
	}).map((device) => {
		return Object.assign({}, device, {
			path: `/dev/${device.name}`
		});
	}).map((device) => {
		/* FIXME: Check whether we need to iterate through child disks as well, when dealing with eg. RAID arrays */
		return Promise.try(() => {
			return Promise.all([
				smartctl.info({ devicePath: device.path }),
				smartctl.attributes({ devicePath: device.path })
			]);
		}).then(([info, attributes]) => {
			return Object.assign({}, device, {
				information: info,
				smartData: attributes,
				smartStatus: getSmartStatus(attributes)
			});
		});
	}).then((blockDevices) => {
		console.log(blockDevices);
		return blockDevices;
	});
}

function sumDriveSizes(drives) {
	return drives.reduce((total, device) => {
		return total + device.size.toB().amount;
	}, 0);
}

function roundUnit(unit) {
	return Object.assign(unit, {
		amount: Math.round(unit.amount * 100) / 100
	});
}

module.exports = function({db}) {
	let router = require("express-promise-router")();

	router.get("/", (req, res) => {
		return Promise.try(() => {
			return getStorageDevices();
		}).then((devices) => {
			/* FIXME: Auto-formatting of total sizes and units */
			let fixedDrives = devices.filter((drive) => drive.removable === false);
			let removableDrives = devices.filter((drive) => drive.removable === true);

			let healthyFixedDrives = fixedDrives.filter((drive) => drive.smartStatus === "healthy");
			let deterioratingFixedDrives = fixedDrives.filter((drive) => drive.smartStatus === "deteriorating");
			let failingFixedDrives = fixedDrives.filter((drive) => drive.smartStatus === "failing");

			res.render("hardware/storage-devices/list", {
				devices: devices,
				totalFixedStorage: roundUnit(B(sumDriveSizes(fixedDrives)).toTiB()),
				totalHealthyFixedStorage: roundUnit(B(sumDriveSizes(healthyFixedDrives)).toTiB()),
				totalDeterioratingFixedStorage: roundUnit(B(sumDriveSizes(deterioratingFixedDrives)).toTiB()),
				totalFailingFixedStorage: roundUnit(B(sumDriveSizes(failingFixedDrives)).toTiB()),
				totalRemovableStorage: roundUnit(B(sumDriveSizes(removableDrives)).toGiB())
			});
		});
	});

	return router;
}