import {
	getMonitorByIdParamValidation,
	getMonitorByIdQueryValidation,
	getMonitorsByTeamIdValidation,
	createMonitorBodyValidation,
  getMonitorURLByQueryValidation,
	editMonitorBodyValidation,
	getMonitorsAndSummaryByTeamIdParamValidation,
	getMonitorsAndSummaryByTeamIdQueryValidation,
	getMonitorsByTeamIdQueryValidation,
	pauseMonitorParamValidation,
	getMonitorStatsByIdParamValidation,
	getMonitorStatsByIdQueryValidation,
	getCertificateParamValidation,
} from "../validation/joi.js";
import sslChecker from "ssl-checker";
import { errorMessages, successMessages } from "../utils/messages.js";
import jwt from "jsonwebtoken";
import { getTokenFromHeaders } from "../utils/utils.js";
import logger from "../utils/logger.js";
import { handleError, handleValidationError } from "./controllerUtils.js";
import dns from "dns";

const SERVICE_NAME = "monitorController";

/**
 * Returns all monitors
 * @async
 * @param {Express.Request} req
 * @param {Express.Response} res
 * @param {function} next
 * @returns {Promise<Express.Response>}
 * @throws {Error}
 */
const getAllMonitors = async (req, res, next) => {
	try {
		const monitors = await req.db.getAllMonitors();
		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_GET_ALL,
			data: monitors,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getAllMonitors"));
	}
};

/**
 * Returns monitor stats for monitor with matching ID
 * @async
 * @param {Express.Request} req
 * @param {Express.Response} res
 * @param {function} next
 * @returns {Promise<Express.Response>}
 * @throws {Error}
 */
const getMonitorStatsById = async (req, res, next) => {
	try {
		await getMonitorStatsByIdParamValidation.validateAsync(req.params);
		await getMonitorStatsByIdQueryValidation.validateAsync(req.query);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const monitorStats = await req.db.getMonitorStatsById(req);
		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_STATS_BY_ID,
			data: monitorStats,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getMonitorStatsById"));
	}
};

const getMonitorCertificate = async (req, res, next, fetchMonitorCertificate) => {
	try {
		await getCertificateParamValidation.validateAsync(req.params);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
	}

	try {
		const { monitorId } = req.params;
		const monitor = await req.db.getMonitorById(monitorId);
		const certificate = await fetchMonitorCertificate(sslChecker, monitor);
		if (certificate && certificate.validTo) {
			return res.status(200).json({
				success: true,
				msg: successMessages.MONITOR_CERTIFICATE,
				data: {
					certificateDate: new Date(certificate.validTo),
				},
			});
		} else {
			return res.status(200).json({
				success: true,
				msg: successMessages.MONITOR_CERTIFICATE,
				data: { certificateDate: "N/A" },
			});
		}
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getMonitorCertificate"));
	}
};

/**
 * Retrieves a monitor by its ID.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.monitorId - The ID of the monitor to be retrieved.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message, and the retrieved monitor data.
 * @throws {Error} If there is an error during the process, especially if the monitor is not found (404) or if there is a validation error (422).
 */
const getMonitorById = async (req, res, next) => {
	try {
		await getMonitorByIdParamValidation.validateAsync(req.params);
		await getMonitorByIdQueryValidation.validateAsync(req.query);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const monitor = await req.db.getMonitorById(req.params.monitorId);
		if (!monitor) {
			const error = new Error(errorMessages.MONITOR_GET_BY_ID);
			error.status = 404;
			throw error;
		}

		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_GET_BY_ID,
			data: monitor,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getMonitorById"));
	}
};

/**
 * Retrieves all monitors and a summary for a team based on the team ID.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.teamId - The ID of the team.
 * @property {Object} req.query - The query parameters of the request.
 * @property {string} req.query.type - The type of the request.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message, and the data containing the monitors and summary for the team.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422).
 */
const getMonitorsAndSummaryByTeamId = async (req, res, next) => {
	try {
		await getMonitorsAndSummaryByTeamIdParamValidation.validateAsync(req.params);
		await getMonitorsAndSummaryByTeamIdQueryValidation.validateAsync(req.query);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const { teamId } = req.params;
		const { type } = req.query;
		const monitorsSummary = await req.db.getMonitorsAndSummaryByTeamId(teamId, type);
		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_GET_BY_USER_ID(teamId),
			data: monitorsSummary,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getMonitorsAndSummaryByTeamId"));
	}
};

/**
 * Retrieves all monitors associated with a team by the team's ID.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.teamId - The ID of the team.
 * @property {Object} req.query - The query parameters of the request.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message, and the data containing the monitors for the team.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422).
 */
const getMonitorsByTeamId = async (req, res, next) => {
	try {
		await getMonitorsByTeamIdValidation.validateAsync(req.params);
		await getMonitorsByTeamIdQueryValidation.validateAsync(req.query);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const teamId = req.params.teamId;
		const monitors = await req.db.getMonitorsByTeamId(req, res);
		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_GET_BY_USER_ID(teamId),
			data: monitors,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "getMonitorsByTeamId"));
		next(error);
	}
};

/**
 * Creates a new monitor and adds it to the job queue.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.body - The body of the request.
 * @property {Array} req.body.notifications - The notifications associated with the monitor.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message indicating the creation of the monitor, and the created monitor data.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422).
 */
const createMonitor = async (req, res, next) => {
	try {
		await createMonitorBodyValidation.validateAsync(req.body);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const notifications = req.body.notifications;
		const monitor = await req.db.createMonitor(req, res);

		if (notifications && notifications.length !== 0) {
			monitor.notifications = await Promise.all(
				notifications.map(async (notification) => {
					notification.monitorId = monitor._id;
					await req.db.createNotification(notification);
				})
			);
			await monitor.save();
		}
		// Add monitor to job queue
		req.jobQueue.addJob(monitor._id, monitor);
		return res.status(201).json({
			success: true,
			msg: successMessages.MONITOR_CREATE,
			data: monitor,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "createMonitor"));
	}
};

/**
 * Checks if the endpoint can be resolved
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.query - The query parameters of the request.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message, and the resolution result.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422).
 */
const checkEndpointResolution = async (req, res, next) => {
  try {
		await getMonitorURLByQueryValidation.validateAsync(req.query);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

  try {
    let { monitorURL } = req.query;
    monitorURL = new URL(monitorURL);
    await new Promise((resolve, reject) => {
      dns.resolve(monitorURL.hostname, (error) => {
        if (error) {
          reject(error);
        }
        resolve();
      });
    });
    return res.status(200).json({
      success: true,
      msg: `URL resolved successfully`,
    });
  } catch (error) {
    next(handleError(error, SERVICE_NAME, "checkEndpointResolution"));
  }
}

/**
 * Deletes a monitor by its ID and also deletes associated checks, alerts, and notifications.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.monitorId - The ID of the monitor to be deleted.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status and a message indicating the deletion of the monitor.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422) or an error in deleting associated records.
 */
const deleteMonitor = async (req, res, next) => {
	try {
		await getMonitorByIdParamValidation.validateAsync(req.params);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const monitor = await req.db.deleteMonitor(req, res, next);
		// Delete associated checks,alerts,and notifications
		try {
			await req.jobQueue.deleteJob(monitor);
			await req.db.deleteChecks(monitor._id);
			await req.db.deletePageSpeedChecksByMonitorId(monitor._id);
			await req.db.deleteNotificationsByMonitorId(monitor._id);
		} catch (error) {
			logger.error(
				`Error deleting associated records for monitor ${monitor._id} with name ${monitor.name}`,
				{
					method: "deleteMonitor",
					service: SERVICE_NAME,
					error: error.message,
				}
			);
		}
		return res.status(200).json({ success: true, msg: successMessages.MONITOR_DELETE });
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "deleteMonitor"));
	}
};

/**
 * Deletes all monitors associated with a team.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.headers - The headers of the request.
 * @property {string} req.headers.authorization - The authorization header containing the JWT token.
 * @param {Object} res - The Express response object.
 * @param {function} next
 * @returns {Object} The response object with a success status and a message indicating the number of deleted monitors.
 * @throws {Error} If there is an error during the deletion process.
 */
const deleteAllMonitors = async (req, res, next) => {
	try {
		const token = getTokenFromHeaders(req.headers);
		const { jwtSecret } = req.settingsService.getSettings();
		const { teamId } = jwt.verify(token, jwtSecret);
		const { monitors, deletedCount } = await req.db.deleteAllMonitors(teamId);
		await Promise.all(
			monitors.map(async (monitor) => {
				try {
					await req.jobQueue.deleteJob(monitor);
					await req.db.deleteChecks(monitor._id);
					await req.db.deletePageSpeedChecksByMonitorId(monitor._id);
					await req.db.deleteNotificationsByMonitorId(monitor._id);
				} catch (error) {
					logger.error(
						`Error deleting associated records for monitor ${monitor._id} with name ${monitor.name}`,
						{
							method: "deleteAllMonitors",
						}
					);
				}
			})
		);
		return res
			.status(200)
			.json({ success: true, msg: `Deleted ${deletedCount} monitors` });
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "deleteAllMonitors"));
	}
};

/**
 * Edits a monitor by its ID, updates its notifications, and updates its job in the job queue.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.monitorId - The ID of the monitor to be edited.
 * @property {Object} req.body - The body of the request.
 * @property {Array} req.body.notifications - The notifications to be associated with the monitor.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message indicating the editing of the monitor, and the edited monitor data.
 * @throws {Error} If there is an error during the process, especially if there is a validation error (422).
 */
const editMonitor = async (req, res, next) => {
	try {
		await getMonitorByIdParamValidation.validateAsync(req.params);
		await editMonitorBodyValidation.validateAsync(req.body);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
		return;
	}

	try {
		const { monitorId } = req.params;
		const monitorBeforeEdit = await req.db.getMonitorById(monitorId);

		// Get notifications from the request body
		const notifications = req.body.notifications;

		const editedMonitor = await req.db.editMonitor(monitorId, req.body);

		await req.db.deleteNotificationsByMonitorId(editedMonitor._id);

		if (notifications && notifications.length !== 0) {
			await Promise.all(
				notifications.map(async (notification) => {
					notification.monitorId = editedMonitor._id;
					await req.db.createNotification(notification);
				})
			);
		}

		// Delete the old job(editedMonitor has the same ID as the old monitor)
		await req.jobQueue.deleteJob(monitorBeforeEdit);
		// Add the new job back to the queue
		await req.jobQueue.addJob(editedMonitor._id, editedMonitor);
		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_EDIT,
			data: editedMonitor,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "editMonitor"));
	}
};

/**
 * Pauses or resumes a monitor based on its current state.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.params - The parameters of the request.
 * @property {string} req.params.monitorId - The ID of the monitor to be paused or resumed.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message indicating the new state of the monitor, and the updated monitor data.
 * @throws {Error} If there is an error during the process.
 */
const pauseMonitor = async (req, res, next) => {
	try {
		await pauseMonitorParamValidation.validateAsync(req.params);
	} catch (error) {
		next(handleValidationError(error, SERVICE_NAME));
	}

	try {
		const monitor = await req.db.getMonitorById(req.params.monitorId);
		if (monitor.isActive) {
			await req.jobQueue.deleteJob(monitor);
		} else {
			await req.jobQueue.addJob(monitor._id, monitor);
		}
		monitor.isActive = !monitor.isActive;
		monitor.status = undefined;
		monitor.save();
		return res.status(200).json({
			success: true,
			msg: monitor.isActive
				? successMessages.MONITOR_RESUME
				: successMessages.MONITOR_PAUSE,
			data: monitor,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "pauseMonitor"));
	}
};

/**
 * Adds demo monitors for a team.
 * @async
 * @param {Object} req - The Express request object.
 * @property {Object} req.headers - The headers of the request.
 * @property {string} req.headers.authorization - The authorization header containing the JWT token.
 * @param {Object} res - The Express response object.
 * @param {function} next - The next middleware function.
 * @returns {Object} The response object with a success status, a message indicating the addition of demo monitors, and the number of demo monitors added.
 * @throws {Error} If there is an error during the process.
 */
const addDemoMonitors = async (req, res, next) => {
	try {
		const token = getTokenFromHeaders(req.headers);
		const { jwtSecret } = req.settingsService.getSettings();
		const { _id, teamId } = jwt.verify(token, jwtSecret);
		const demoMonitors = await req.db.addDemoMonitors(_id, teamId);
		await Promise.all(
			demoMonitors.map((monitor) => req.jobQueue.addJob(monitor._id, monitor))
		);

		return res.status(200).json({
			success: true,
			msg: successMessages.MONITOR_DEMO_ADDED,
			data: demoMonitors.length,
		});
	} catch (error) {
		next(handleError(error, SERVICE_NAME, "addDemoMonitors"));
	}
};

export {
	getAllMonitors,
	getMonitorStatsById,
	getMonitorCertificate,
	getMonitorById,
	getMonitorsAndSummaryByTeamId,
	getMonitorsByTeamId,
	createMonitor,
  checkEndpointResolution,
	deleteMonitor,
	deleteAllMonitors,
	editMonitor,
	pauseMonitor,
	addDemoMonitors,
};