import debounce from 'just-debounce-it';
import { watch } from 'node:fs';
import { stat, readFile, writeFile } from 'node:fs/promises';
import { join } from 'node:path';
import readline from 'node:readline/promises';
import { parse } from 'ini';
import MDBReader from 'mdb-reader';
import { diff } from 'just-diff';
import { version } from './package.json';

console.log(`FDLogUp Client v${version}`);

const rl = readline.createInterface({
	input: process.stdin,
	output: process.stdout
});

async function promptToClose(message: string) {
	await rl.question(`== ${message}\n== Press enter to quit.`);
	process.exit(0);
}

// Check for config.ini file
const configPath = join(process.cwd(), 'config.ini');
try {
	const configStat = await stat(configPath);
	if (configStat.isDirectory()) await promptToClose('The config file must be a file.');
} catch (e) {
	await writeFile(configPath, [
		'; The database file to upload, defaults to C:\\Users\\<user>\\Documents\\Affirmatech\\N3FJP Software\\ARRL-Field-Day\\LogData.mdb',
		`; database_file = "${process.env.USERNAME ? `C:\\Users\\${process.env.USERNAME}\\Documents\\Affirmatech\\N3FJP Software\\ARRL-Field-Day\\LogData.mdb` : ''}"`,
		'',
		'; The endpoint to upload to',
		'log_endpoint = "https://example.local/up"'
	].join('\n'))
	await promptToClose('Failed to find config file. A new one was created, so put in your variables in there.');
}

let databaseFile: string;
let logEndpoint: string;
try {
	const config = parse(await readFile(configPath, { encoding: 'utf-8' }));
	databaseFile = config.database_file;
	logEndpoint = config.log_endpoint;
	if (!logEndpoint) await promptToClose('A log endpoint is required in the config file.');
} catch (e) {
	databaseFile = '';
	await promptToClose('Failed to parse config file. You can remove the file and re-run this program if more problems occur.');
}

const dbPath = databaseFile ?? process.env.USERNAME ? join('C:/Users', process.env.USERNAME!, 'Documents/Affirmatech/N3FJP Software/ARRL-Field-Day/LogData.mdb') : '';

// Check for log file
try {
	if (!dbPath) await promptToClose('A log path is needed to use this program.');
	const fileStat = await stat(dbPath);
	if (fileStat.isDirectory()) await promptToClose('The log path must point to a file.');
	console.log(`\n== Following changes for the file "${dbPath}"\n== Ctrl-C to exit.\n`);
} catch (e) {
	await promptToClose(`Failed to find log file at "${dbPath}"`);
}

// Upload logic
let lastData: Record<string, any> = {};
async function _upload() {
	try {
		console.log('-- Reading log...');
		const reader = new MDBReader(await readFile(dbPath));
		if (!reader.getTableNames().includes('tblContacts'))
			return console.log('!! No "tblContacts" table present.');

		const table = reader.getTable('tblContacts');
		const tableData = table.getData<Record<string, string>>();

		const data = tableData.reduce((p, r) => ({ ...p, [r.fldPrimaryKey]: r }), {} as Record<string, any>);
		const differences = diff(lastData, data);
		const changedIds = [...new Set(differences.filter((r) => r.op !== 'remove').map((r) => r.path[0]))];
		const changedRows = changedIds.map((id) => data[id]);

		if (changedIds.length === 0) return void console.log('-- No changes found.');

		try {

			console.log(`-> Uploading ${changedIds.length.toLocaleString()} row(s)...`);
			const response = await fetch(logEndpoint, {
				method: 'POST',
				body: JSON.stringify(changedRows),
				headers: {
					'Content-Type': 'application/json'
				}
			});
			console.log(`<- Recieved ${response.status} (${response.statusText})`);
			if (response.status === 200) lastData = data;
		} catch (e) {
			console.log('-! Failed to send log');
			console.error(e);
		}
	} catch (e) {
		console.log('-! Failed to upload');
		console.error(e);
	}
}

const upload = debounce(_upload, 250);

const watcher = watch(dbPath, (event, filename) => {
	if (event === 'rename') return void console.log(`== ${filename} was renamed, something might break`);
	upload();
});

process.on("SIGINT", () => {
	// close watcher when Ctrl-C is pressed
	console.log('\n== Closing watcher...');
	watcher.close();

	process.exit(0);
});
rl.close();

// "Upload first" option
if (process.argv[2] === '--upload') _upload();