// Update the version numbers and library sizes in index.md

var fs = require('fs'),
    zlib = require('zlib');

var VIS = 'vis.js',
    VIS_MIN = 'vis.min.js',
    INDEX = 'index.html';

// get development size
function developmentSize(callback) {
    fs.readFile(VIS, function (err, data) {
        if (!err) {
            var size = Math.round(data.length / 1024) + ' kB';
            callback(null, size);
        }
        else {
            callback(err);
        }
    });
}

// get (gzipped) production size
function productionSize(callback) {
    fs.readFile(VIS_MIN, function (err, data) {
        if (!err) {
            zlib.gzip(data, function (err, data) {
                if (!err) {
                    var size = Math.round(data.length / 1024) + ' kB';
                    callback(null, size)
                }
                else {
                    callback(err);
                }
            });
        }
        else {
            callback(err);
        }
    });
}

// get version
function version(callback) {
    fs.readFile(VIS_MIN, function (err, data) {
        if (!err) {
            var match = /@version\s*([\w\.-]*)/i.exec(data);
            var version = undefined;
            if (match) {
                version = match[1];
            }
            callback(null, version);
        }
        else {
            callback(err);
        }
    });
}

// update version and library sizes in index.md
function updateVersion(developmentSize, productionSize, version, callback) {
    fs.readFile(INDEX, function (err, data) {
        if (!err) {
            data = String(data);
            data = data.replace(/<span id="development-size">([\w\s]*)<\/span>/g,
                '<span id="development-size">' + developmentSize + '</span>');

            data = data.replace(/<span id="production-size">([\w\s]*)<\/span>/g,
                '<span id="production-size">' + productionSize + '</span>');

            data = data.replace(/<span class="version">([\w\.-]*)<\/span>/g,
                '<span class="version">' + version + '</span>');

            fs.writeFile(INDEX, data, callback);
        }
        else {
            callback(err);
        }
    });
}

developmentSize(function (err, devSize) {
    console.log('development size: ' + devSize);
    productionSize(function (err, prodSize) {
        console.log('production size: ' + prodSize);
        version(function (err, version) {
            console.log('version: ' + version);
            if (devSize && prodSize && version) {
                updateVersion(devSize, prodSize, version, function (err, res) {
                    if (err) {
                        console.log(err);
                    }
                    else {
                        console.log('done');
                    }
                });
            }
            else {
            }
        });
    });
});