var crypto = require('crypto');
var fs = require('fs');
var fse = require('fs-extra');
var path = require('path');
var child_process = require('child_process');
var co = require('co');

var Builder = module.exports = function(basePath, sources) {
	this.config = {}; 
	this.id = null;
	this.libPath = path.join(__dirname, '..', 'libraries');
	this.libs = [];
	this.basePath = basePath;
	this.sources = sources || {};
	this.workingPath = '';
	this.platform = 'uno'
};

Builder.prototype.init = function(callback) {
	var self = this;

	this.id = crypto.randomBytes(16).toString('hex').substr(0, 8) + Date.now();
	this.workingPath = path.join(this.basePath, this.id);

	// Create working directory
	fse.mkdirs(this.workingPath, function(err) {

		if (callback)
			callback(err);
	});
};

Builder.prototype.scanLibraries = function(callback) {
	var self = this;

	co(function *() {
		try {
			// Scanning system libraries
			var systemLibs = yield function(done) {
				fs.readdir('/usr/share/arduino/libraries', done);
			};
			self.libs.concat(systemLibs);
		} catch(e) {}

		try {
			// Scanning user libraries
			var userLibs = yield function(done) {
				fs.readdir(self.libPath, done);
			};
			self.libs.concat(userLibs);
		} catch(e) {}

		callback();
	});
};

Builder.prototype.generateMakefile = function(callback) {
	var content = [
		'BOARD_TAG = uno',
		'USER_LIB_PATH = ' + path.join(__dirname, '..', 'libraries'),
		'ARDUINO_LIBS = ' + this.libs.join(' '),
		'ARDUINO_DIR = /usr/share/arduino',
		'include /usr/share/arduino/Arduino.mk'
	];

	fse.outputFile(path.join(this.workingPath, 'Makefile'), content.join('\n'), callback);
};

Builder.prototype.generateSources = function(callback) {

	var self = this;
	co(function *() {

		// Generating all source files
		for (var filename in self.sources) {
			var filepath = path.join(self.workingPath, filename);

			yield function(done) {
				fse.outputFile(filepath, self.sources[filename], done);
			};
		}

		// Everything was done
		if (callback)
			callback();
	});
};

Builder.prototype.compile = function(callback) {
	var self = this;

	child_process.exec('make -C ' + this.workingPath, function(err, cmdout, cmderr) {

		if (err) {
			callback(err);
		} else if (callback) {
			return callback(null, path.join(self.workingPath, 'build-uno', self.id + '.hex'));
		}
	});

};