/*
This file is part of »type2«.

Copyright 2016-2018 'Christian Fraß, Christian Neubauer, Martin Springwald GbR'
<info@greenscale.de>

»type2« is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

»type2« is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License
along with »type2«. If not, see <http://www.gnu.org/licenses/>.
 */


const _fs = require("fs");


/**
 * @author fenris
 */
type type_parameters = {path ?: string; input ?: Array<char>;};


/**
 * @author fenris
 */
type type_foo_1 = {parameters : type_parameters; reader : type_myreader;};


/**
 * @author fenris
 */
type type_foo_2 = lib_lang.type_tree<lib_lang.type_terminal_default>;


/**
 * @author fenris
 */
type type_myreader = lib_lang.class_reader<char, lib_lang.type_terminal_default, string, type_foo_2>;


/**
 * @author fenris
 */
function generate_reader(
	path : string
) : lib_call.type_promise<type_myreader, Error>
{
	return (
		lib_call.promise_resolve<void, Error>(undefined)
		.then<string/*, Error*/>(
			() => lib_file.read_promise(path)
		)
		.then<any/*, Error*/>(
			(content) => lib_call.promise_resolve<any, Error>(
				JSON.parse(content)
			)
		)
		.then<type_myreader/*, Error*/>(
			(data) => lib_call.promise_resolve<type_myreader, Error>(
				lib_lang.class_reader.default_raw(data)
			)
		)
	);
}


/**
 * @author fenris
 */
function transform_arguments(
	args : Array<string>
) : type_parameters
{
	let parameters : type_parameters = {};
	// path
	{
		const path : string = (
			(args.length >= 1)
			? args.shift()
			: null
		);
		if (path == null) {
			throw (new Error("no path specified"))
		}
		else {
			parameters["path"] = path;
		}
	}
	// input
	{
		let input : Array<char>;
		const input_raw : string = args.join(" ");
		if (input_raw == "") {
			throw (new Error("no input given"));
		}
		else {
			input = input_raw.split("");
			parameters["input"] = input;
		}
	}
	return parameters;
}


/**
 * @author fenris
 */
function main(
	args : Array<string>
) : lib_call.type_promise<void, Error>
{
	return (
		lib_call.promise_resolve<void, Error>(undefined)
		.then<string/*, Error*/>(
			() => lib_call.promise_make<string, Error>(
				(resolve, reject) => {
					// TODO: outsource reading from stdin to a plankton module
					let input_raw : string = "";
					process.stdin.setEncoding(
						"utf8"
					);
					process.stdin.on(
						"readable",
						() => {
							let chunk : string;
							while ((chunk = process.stdin.read()) !== null) {
								input_raw += chunk;
							}
						}
					);
					process.stdin.on(
						"end",
						() => {
							resolve(input_raw);
						}
					);
				}
			)
		)
		.then<type_parameters/*, Error*/>(
			(input_raw) => lib_call.promise_resolve<type_parameters, Error>(
				transform_arguments([args[0], input_raw])
			)
		)
		.then<type_foo_1/*, Error*/>(
			(parameters) => (
				generate_reader(parameters.path)
				.then<type_foo_1/*, Error*/>(
					(reader) => lib_call.promise_resolve<type_foo_1, Error>(
						{
							"parameters": parameters,
							"reader": reader,
						}
					)
				)
			)
		)
		.then<type_foo_2/*, Error*/>(
			(vars) => {
				lib_log.level_push(1);
				const result : type_foo_2 = vars.reader.run(vars.parameters.input);
				lib_log.level_pop();
				if (result == null) {
					return lib_call.promise_reject<type_foo_2, Error>(new Error("didn't work"));
				}
				else {
					return lib_call.promise_resolve<type_foo_2, Error>(result);
				}
			}
		)
		.then<void/*, Error*/>(
			(result) => {
				console.info(JSON.stringify(result, undefined, "\t"));
				return lib_call.promise_resolve<void, Error>(undefined);
			}
		)
	);
}


/**
 * @author fenris
 */
main(process.argv.slice(2))
.then(
	(output) => {
		// console.info("--", "done:", output);
	},
	(error) => {
		console.error("--", "failed:", error);
	}
);