#!/usr/bin/env node

/*
    Downloads translation json files from Transifex for all the languages defined
    in the menus. Expects a Transifex API key to be set in the TX_TOKEN environment
    variable. Takes as input a directory in which to store the translations.

    Creates subdirectories for each view and 'general'. Creates <lang>.json files
    for each language downloaded. Uses the english source l10n file if there is
    an error.
*/
var fs = require('fs');
var path = require('path');
var async = require('async');
var Transifex = require('transifex');
var languages = require('../languages.json');
var routes = require('../src/routes.json');


// -----------------------------------------------------------------------------
// Main script
// -----------------------------------------------------------------------------


var args = process.argv.slice(2);

if (!args.length) {
    process.stdout.write('A destination directory for localizations must be specified.');
    process.exit(1);
}

var outputDir = path.resolve(__dirname, '../', args.shift());
try {
    fs.accessSync(outputDir, fs.F_OK);
} catch (err) {
    // Doesn't exist - create it.
    fs.mkdirSync(outputDir);
}

if (process.env.TX_TOKEN) {
    var transifex = new Transifex({
        project_slug: 'scratch-website',
        credential: 'api:'+process.env.TX_TOKEN
    });
} else {
    process.stdout.write('WARNING: Missing Transifex API key, skipping download.\n');
    process.stdout.write('Set TX_TOKEN in env if you want translations.\n');
    process.exit(0);
}

//make sure general translation directory exists
var transDir = path.resolve(outputDir + '/general');
try {
    fs.accessSync(transDir, fs.F_OK);
} catch (err) {
    // Doesn't exist - create it.
    fs.mkdirSync(transDir);
}

var localizations = [];
for ( var isoCode in languages ) {
    var transFile = transDir + '/' + isoCode + '.json';
    localizations.push({view: 'general', lang: isoCode, file: transFile, src: 'l10n.json'});
}

// initialize views, ignore redirect routes
for (var v in routes) {
    if (typeof routes[v].redirect !== 'undefined') {
        continue;
    }
    var subdir = routes[v].view.split('/');
    subdir.pop();
    var l10n = 'src/views/' + subdir.join('/') + '/l10n.json';
    var name = routes[v].name;
    try {
        // only Initialize if there is an l10n file
        fs.accessSync(l10n);
        transDir = path.resolve(outputDir + '/' + name);
        try {
            fs.accessSync(transDir, fs.F_OK);
        } catch (err) {
            // Doesn't exist - create it.
            fs.mkdirSync(transDir);
        }
        for ( var isoCode in languages ) {
            var transFile = transDir + '/' + isoCode + '.json';
            localizations.push({view: name, lang: isoCode, file: transFile, src: l10n});
        }

    } catch (err) {
        // skip views without l10n files
        // TODO: ES6
        // process.stdout.write(`Skipping ${name}, no l10n\n`);
        process.stdout.write('Skipping ' + name+ ', no l10n\n');
    }
}

async.forEachLimit(localizations, 3, function (item, cb) {
    transifex.translationInstanceMethod(
        'scratch-website',
        item.view+'-l10njson',
        item.lang,
        {mode: 'reviewed'},
        function (err, data) {
            if (err) {
                process.stdout.write(item.view + ': ' + item.lang + '(' + err + ')' + ' using english\n');
                fs.createReadStream(item.src).pipe(fs.createWriteStream(item.file));
            } else {
                fs.writeFile(item.file, data);
            }
            return;
        });
    cb();
}, function (err) {
    if (err) {
        process.stdout.write('Import completed with errors\n');
    }
    return;
});