/*
Node-OpenDroneMap Node.js App and REST API to access OpenDroneMap.
Copyright (C) 2016 Node-OpenDroneMap Contributors

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

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
"use strict";
let fs = require('fs');
let path = require('path');
let assert = require('assert');
let spawn = require('child_process').spawn;
let config = require('../config.js');
let logger = require('./logger');


function makeRunner(command, args, requiredOptions = [], outputTestFile = null){
	return function(options, done, outputReceived){
		for (let requiredOption of requiredOptions){
			assert(options[requiredOption] !== undefined, `${requiredOption} must be defined`);
		}

		let commandArgs = args;
		if (typeof commandArgs === 'function') commandArgs = commandArgs(options);

		logger.info(`About to run: ${command} ${commandArgs.join(" ")}`);

		if (config.test){
			logger.info("Test mode is on, command will not execute");

			if (outputTestFile){
				fs.readFile(path.resolve(__dirname, outputTestFile), 'utf8', (err, text) => {
					if (!err){
						let lines = text.split("\n");
						lines.forEach(line => outputReceived(line));
						
						done(null, 0, null);
					}else{
						logger.warn(`Error: ${err.message}`);
						done(err);
					}
				});
			}

			return;// Skip rest
		}

		// Launch
		let childProcess = spawn(command, commandArgs);

		childProcess
			.on('exit', (code, signal) => done(null, code, signal))
			.on('error', done);

		childProcess.stdout.on('data', chunk => outputReceived(chunk.toString()));
		childProcess.stderr.on('data', chunk => outputReceived(chunk.toString()));

		return childProcess;
	};
}


module.exports = {
	runTiler: makeRunner("gdal2tiles.py",
						 function(options){
						 	return ["-z", options.zoomLevels,
								"-n", 
								"-w", "none",
								options.inputFile, 
								options.outputDir
							];
						 },
						 ["zoomLevels", "inputFile", "outputDir"],
						 path.join("..", "tests", "gdal2tiles_output.txt")),

	runPotreeConverter: makeRunner("PotreeConverter",
									function(options){
										return [options.inputFile,
												"-o", options.outputDir];
									},
									["inputFile", "outputDir"],
									path.join("..", "tests", "potree_output.txt"))
};