import * as process from 'process';
import express from 'express';
import * as path from 'path';
import { getLanguagesFilesPaths } from './files.handler';
import { I18n4e, InitOptions } from './interfaces';
import { i18nServerSideMiddlewareWrapper } from './middlewares';
import { CallSite } from './types';
import { clientRoutes } from './routes';
import { createDefaultSession } from './session';

function getCallerFile(position: number = 2): string | undefined {
	if (position >= Error.stackTraceLimit) {
		throw new TypeError(
			'getCallerFile(position) requires position be less than Error.stackTraceLimit but position was: `' +
				position +
				'` and Error.stackTraceLimit was: `' +
				Error.stackTraceLimit +
				'`'
		);
	}

	const oldPrepareStackTrace = Error.prepareStackTrace;
	Error.prepareStackTrace = (err, stack) => stack;
	const err = new Error();
	const stack = err.stack as unknown as CallSite[];
	Error.prepareStackTrace = oldPrepareStackTrace;

	if (stack !== null && typeof stack === 'object') {
		const callSite = stack[position];
		return callSite ? callSite.getFileName() || undefined : undefined;
	}
	return undefined;
}

const i18n4e: I18n4e = {
	langsFilesPath: {},
	defaultLang: 'en',
	localesFolder: '',
	langNameInPath: false,
	enableClient: false,
	useLangSession: false,
	init: (app: express.Application, options: InitOptions = {}): Promise<any> => {
		if (options.i18n4eDefaultSession) createDefaultSession(app, options.dev);
		i18nServerSideMiddlewareWrapper(app, i18n4e, options.dev, options);

		if (options.enableClient) i18n4e.enableClient = options.enableClient;
		if (options.defaultLang) i18n4e.defaultLang = options.defaultLang;
		if (options.langNameInPath) i18n4e.langNameInPath = options.langNameInPath;
		if (options.enableClient) i18n4e.enableClient = options.enableClient;
		if (options.useLangSession) i18n4e.useLangSession = options.useLangSession;

		let caller = getCallerFile(2);
		//if (!caller || typeof caller != 'string')
		//	throw new Error('i18n4e (Init Error): Unable to get caller path.');
		if (caller) {
			if (caller.includes('file')) caller = caller.split('///')[1];
			const finalPath = path.dirname(caller);
			options.langsFolder = options.langsFolder
				? path.resolve(finalPath || './', options.langsFolder)
				: finalPath + '/_locales';
			i18n4e.localesFolder = options.langsFolder;
		}
		return getLanguagesFilesPaths(options)
			.then((filesPaths: any) => {
				i18n4e.langsFilesPath = filesPaths;
				if (options.enableClient) clientRoutes(app, i18n4e);

				return filesPaths;
			})
			.catch((err: Error) => {
				console.error(
					`\x1b[3m\x1b[34m[i18n4e\x1b[0m \x1b[31m\x1b[1mError\x1b[0m \x1b[3m\x1b[34m(On Init)]\x1b[0m  --> \x1b[31m\x1b[1m${err.message}\x1b[0m`
				);
				throw new Error('i18n4e (Init Error)');
			});
	},
};

export { i18n4e };