#!/usr/bin/env node
'use strict';

var UhkConnection = require('./UhkConnection');
var R = require('ramda');
var path = require('path');

var ENUMERATION_MODE_IDS = R.pluck('id', UhkConnection.ENUMERATION_MODES);
var commands = getTypistFriendlyObjectKeys(R.keys(UhkConnection.COMMANDS));
var args = process.argv.slice(1);
var programName = path.basename(args.shift());
var commandArg = args.shift();

if (!R.contains(commandArg, commands)) {
    console.error('Usage: ' + programName + ' COMMAND [ARG]');
    console.error(commandArg === undefined
        ? 'No command has been specified.'
        : 'Command "' + commandArg + '" is invalid.');
    console.error('Valid commands: ' + commands.join(', '));
    exitWithError();
}

var command = UhkConnection.COMMANDS[getTypistUnfriendlyObjectKey(commandArg)];
var uhkConnection;

switch (command) {
    case UhkConnection.COMMANDS.DETECT:
        uhkConnection = new UhkConnection(/*UhkConnection.LOG_LEVELS.TRANSFER*/);
        uhkConnection.connect(function(error) {
            if (error) {
                console.error(error);
                exitWithError();
            }
        });
        break;
    case UhkConnection.COMMANDS.REENUMERATE:
        var enumerationModeArg = args.shift();
        var enumerationModes = getTypistFriendlyObjectKeys(ENUMERATION_MODE_IDS);
        if (!R.contains(enumerationModeArg, enumerationModes)) {
            console.error('Usage: %s %s {%s}', programName, commandArg, enumerationModes.join(' | '));
            console.error(enumerationModeArg === undefined
                ? 'No enumeration mode has been specified.'
                : 'Enumeration mode "%s" is invalid.', enumerationModeArg);
            exitWithError();
        }
        var enumerationMode = R.find(R.propEq('id', getTypistUnfriendlyObjectKey(enumerationModeArg)),
                                     UhkConnection.ENUMERATION_MODES);
        sendRequest(command, enumerationMode.enumerationId, function(error, data) {
            console.log('Reenumerating the UHK in %s mode...', getTypistUnfriendlyObjectKey(enumerationMode.id));
            uhkConnection.waitUntilDisconnect(function() {}, function() {
                console.log('UHK disconnected.');
                uhkConnection.connect(function() {});
            });
        }, false);
        break;
    case UhkConnection.COMMANDS.READ_EEPROM:
        sendRequest(command, null, function(error, data) {
            console.log(data);
        });
        break;
    case UhkConnection.COMMANDS.WRITE_EEPROM:
        var stringToBeSaved = args.shift();
        if (!stringToBeSaved) {
            console.error('A string has to be specified to be saved into the EEPROM.');
            exitWithError();
        }
        sendRequest(command, stringToBeSaved, function(error, data) {});
        break;
}

// Helper functions

function sendRequest(command, arg, callback, shouldReceiveResponse) {
    if (uhkConnection) {
        uhkConnection.sendRequest(command, arg, callback, shouldReceiveResponse);
    } else {
        uhkConnection = new UhkConnection(/*UhkConnection.LOG_LEVELS.TRANSFER*/);
        uhkConnection.connect(function(error) {
            if (error) {
                console.error(error);
                exitWithError();
            }

            uhkConnection.sendRequest(command, arg, callback, shouldReceiveResponse);
        });
    }
}

function getTypistFriendlyObjectKeys(object) {
    return object.map(function(command) {
        return command.toLowerCase().replace(/_/g, '-');
    });
}

function getTypistUnfriendlyObjectKey(key) {
    return key.toUpperCase().replace(/-/g, '_');
}

function exitWithError() {
    process.exit(1);
}