import db from "#root/config/database.config.js";
import cp from 'child_process'

/**
 * Services
 */
import { appService } from "#root/services/index.js";

export const appController = {
	/**
	 * Get application config from database
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	async getConfig(req, res, next) {
		try {
			const data = await appService.getConfig();
			if (!data) return res.status(200).json({ config: null });
			return res.status(200).json({ config: data });
		} catch (error) {
			next(error);
		}
	},

	/**
	 * Update application config
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	async updateConfig(req, res, next) {
		try {
			const config = await appService.getConfig();
			const payload = req.body;
	
			if (!config) await db.run(`INSERT INTO "app_config" (id) VALUES (?)`, [0]);
		
			/* Update TCP configuration */
			if (payload.mb_connection_type === "TCP") {
				const { mb_tcp_ip, mb_tcp_port } = payload;
				await db.run(
						`
						UPDATE "app_config" SET id = 0, mb_connection_type = "TCP", mb_tcp_ip = ?, mb_tcp_port = ?, log_interval_ms = ?
						`,
						[mb_tcp_ip, mb_tcp_port, payload.log_interval_ms],
				);
				return res.status(200).json({ message: "Config Updated." });
			}
		
			/* Update RTU configuration */
			if (payload.mb_connection_type === "RTU") {
				const { mb_rtu_path, mb_rtu_baud, mb_rtu_parity, mb_rtu_data_bits, mb_rtu_stop_bits } = payload;
				await db.run(
						`
						UPDATE "app_config" SET id = 0, 
																		mb_connection_type = "RTU", 
																		mb_rtu_path = ?, 
																		mb_rtu_baud = ?, 
																		mb_rtu_parity = ?, 
																		mb_rtu_data_bits = ?, 
																		mb_rtu_stop_bits = ?,
																		log_interval_ms = ?
						`,
						[mb_rtu_path, mb_rtu_baud, mb_rtu_parity, mb_rtu_data_bits, mb_rtu_stop_bits, payload.log_interval_ms],
				);
				return res.status(200).json({ message: "Config updated." });
			}
		
			return res.status(400).json({ message: "Undefined Modbus connection type." });
		} catch (error) {
			next(error);
		}
	},

	/**
	 * Check whether the application is configured or not
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	async isConfigured(req, res, next) {
		try {
			const config = await appService.getConfig();
			if (!config) return res.status(200).json({ is_configured: false });

			for (const colPrefix of ['mb_tcp', 'mb_rtu']) {
				if (config.mb_connection_type.toLocaleLowerCase() !== colPrefix.substring(3))
					continue;
				const keys = Object.keys(config).filter((k) => k.includes(colPrefix));
				for (const k of keys) {
					if (!config[k])
						return res.status(200).json({ is_configured: false });
				}
			}
		
			return res.status(200).json({ is_configured: true });
		} catch (error) {
			next(error);
		}
	},

	/**
	 * Application memory usage
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	memoryUsage(req, res, next) {
		const memoryUsage = process.memoryUsage();
		const bytesToMB = (bytes) => bytes / 10**6;
		Object.keys(memoryUsage).forEach(k => (memoryUsage[k] = `${bytesToMB(memoryUsage[k])}MB`));
		return res.status(200).json({ data: memoryUsage });
	},
			
	/**
	 * Ping
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	ping(req, res, next) {
		return res.status(200).send('pong');
	},

	/**
	 * Send info about latest commit hash
	 * @param {import('express').Request} req 
	 * @param {import('express').Response} res 
	 * @param {import('express').NextFunction} next 
	 */
	commitHash(req, res, next) {
		const hash = cp.execSync('git rev-parse HEAD').toString().trim();
		return res.status(200).json({ hash })
	}
}