#!/usr/bin/env node

const sharp = require('sharp');
const fs = require('fs');
const program = require('commander');
const chalk = require('chalk');

function increaseVerbosity(v, total) {
    return total + 1;
}

program
    .version('0.1.0', '-V, --version')
    .option('-w, --width <width>', 'The maximum width of each image. Aspect ' +
        'ratio will remain. Images smaller than max will not be scaled.',
        parseInt)
    .option('-v, --verbose', 'Output additional stats, three levels',
        increaseVerbosity, 0)
    .option('-q, --quality <quality>', 'The quality factor for jpg images (no ' +
        'effect for png). Values: 0-100', parseInt)
    .option('-c, --copy_others', 'Copy non jpg or png files to destination ' +
        'directory. Good if you are also includeing PDF or other filetypes in ' +
        'the directory.')
    .arguments('<source> <destination>')
    .action(function(source, destination) {
        var width, quality, copy_others;

        if (!fs.existsSync(source)) {
            console.error(chalk.bold.red('Source directory does not exist, ' +
                'please verify.'));
            process.exit(1);
        }
        if (!fs.existsSync(destination)) {
            console.log('Destination directory does not exist, creating it.')
            fs.mkdirSync(destination);
        }
        program.width ? width = program.width : width = 2560;
        program.quality ? quality = program.quality : quality = 80;
        program.copy_others ? copy_others = program.copy_others : copy_others = false;

        if (quality > 100 || quality < 0) {
            console.error(chalk.bold.red('quality must be greater than 0 and ' +
                'less than 100'));
            process.exit(1);
        }

        fs.readdir(source, function(err, files) {
            var jpg = 0;
            var png = 0;
            var other = 0;
            for (var i in files) {
                file = source + files[i];
                if (file.endsWith('png')) {
                    png++;
                    if (program.verbose > 2)
                        console.log('resize ' + file);
                    sharp(file)
                        .resize(width)
                        .max()
                        .withoutEnlargement(true)
                        .png()
                        .toFile(destination + files[i]);
                } else if (file.endsWith('jpg')) {
                    jpg++;
                    if (program.verbose > 2)
                        console.log('resize ' + file);
                    sharp(file)
                        .resize(width)
                        .max()
                        .withoutEnlargement(true)
                        .jpeg({
                            quality: quality,
                            optimizeScans: true
                        })
                        .toFile(destination + files[i]);
                } else if (copy_others) {
                    other++;
                    if (program.verbose > 2)
                        console.log('move ' + file);
                    fs.createReadStream(file).pipe(fs.createWriteStream(
                        destination + files[i]));
                }
            }
            if (err) {
                console.error(chalk.bold.red(err));
            }
            if (program.verbose > 0) {
                total = png + jpg + other;
                console.log(chalk.bold('================================='));
                console.log(chalk.bold('Processed ' + total + ' files.'));
                if (program.verbose > 1) {
                    console.log('    ' + png + ' png files.');
                    console.log('    ' + jpg + ' jpg files.');
                    console.log('    ' + other + ' other files.');
                }
                if (program.width)
                    console.log('scaled images to ' + width + ' pixels wide');
                if (program.quality)
                    console.log('set quality for jpg to ' + quality + '%');
                console.log('Source: ' + source);
                console.log('Destination: ' + destination);
                console.log(chalk.bold('================================='));
            }
        });
    }).parse(process.argv)