/*******************************
 Build Task
 *******************************/

const
    gulp       = require('gulp'),

    // node dependencies
    console    = require('better-console'),

    // gulp dependencies
    chmod      = require('gulp-chmod'),
    concat     = require('gulp-concat'),
    dedupe     = require('gulp-dedupe'),
    flatten    = require('gulp-flatten'),
    gulpif     = require('gulp-if'),
    header     = require('gulp-header'),
    normalize  = require('normalize-path'),
    plumber    = require('gulp-plumber'),
    print      = require('gulp-print').default,
    rename     = require('gulp-rename'),
    replace    = require('gulp-replace'),
    uglify     = require('gulp-uglify'),

    // config
    config     = require('../config/user'),
    docsConfig = require('../config/docs'),
    tasks      = require('../config/tasks'),
    install    = require('../config/project/install'),

    // shorthand
    globs      = config.globs,
    assets     = config.paths.assets,

    banner     = tasks.banner,
    filenames  = tasks.filenames,
    comments   = tasks.regExp.comments,
    log        = tasks.log,
    settings   = tasks.settings
;

/**
 * Concat and uglify the Javascript files
 * @param {string|array} src - source files
 * @param type
 * @param config
 * @return {*}
 */
function build(src, type, config) {
    return gulp.src(src)
        .pipe(plumber())
        .pipe(flatten())
        .pipe(replace(comments.license.in, comments.license.out))
        .pipe(gulpif(config.hasPermissions, chmod(config.parsedPermissions)))
        .pipe(gulp.dest(config.paths.output.uncompressed))
        .pipe(print(log.created))
        .pipe(uglify(settings.uglify))
        .pipe(rename(settings.rename.minJS))
        .pipe(header(banner, settings.header))
        .pipe(gulpif(config.hasPermissions, chmod(config.parsedPermissions)))
        .pipe(gulp.dest(config.paths.output.compressed))
        .pipe(print(log.created))
    ;
}

/**
 * Packages the Javascript files in dist
 * @param {string} type - type of the js processing (none, rtl, docs)
 * @param {boolean} compress - should the output be compressed
 */
function pack(type, compress) {
    const output         = type === 'docs' ? docsConfig.paths.output : config.paths.output;
    const concatenatedJS = compress ? filenames.concatenatedMinifiedJS : filenames.concatenatedJS;

    return gulp.src(output.uncompressed + '/**/' + globs.components + globs.ignored + '.js')
        .pipe(plumber())
        .pipe(dedupe())
        .pipe(replace(assets.uncompressed, assets.packaged))
        .pipe(concat(concatenatedJS))
        .pipe(gulpif(config.stripHeaders, replace(comments.header.in, comments.header.out)))
        .pipe(gulpif(compress, uglify(settings.concatUglify)))
        .pipe(header(banner, settings.header))
        .pipe(gulpif(config.hasPermissions, chmod(config.parsedPermissions)))
        .pipe(gulp.dest(output.packaged))
        .pipe(print(log.created))
    ;
}

function buildJS(src, type, config, callback) {
    if (!install.isSetup()) {
        console.error('Cannot build Javascript. Run "gulp install" to set-up Fomantic');
        callback();

        return;
    }

    if (callback === undefined) {
        callback = config;
        config = type;
        type = src;
        src = config.paths.source.definitions + '/**/' + config.globs.components + (config.globs.ignored || '') + '.js';
    }

    if (globs.individuals !== undefined && typeof src === 'string') {
        const components = config.globs.components.replace(/[{}]/g, '') + ',' + config.globs.individuals.replace(/[{}]/g, '');

        src = config.paths.source.definitions + '/**/{' + components + '}' + (config.globs.ignored || '') + '.js';
    }

    // copy source javascript
    const js       = () => build(src, type, config);
    js.displayName = 'Building un/compressed Javascript';

    const packUncompressed       = () => pack(type, false);
    packUncompressed.displayName = 'Packing uncompressed Javascript';

    const packCompressed       = () => pack(type, true);
    packCompressed.displayName = 'Packing compressed Javascript';

    gulp.series(js, gulp.parallel(packUncompressed, packCompressed))(callback);
}

module.exports = function (callback) {
    buildJS(false, config, callback);
};

// We keep the changed files in an array to call build with all of them at the same time
let
    timeout,
    files = []
;

module.exports.watch = function (type, config) {
    gulp
        .watch([normalize(config.paths.source.definitions + '/**/*.js')])
        .on('all', function (event, path) {
            // We don't handle deleted files yet
            if (event === 'unlink' || event === 'unlinkDir') {
                return;
            }

            // Clear timeout
            if (timeout) {
                clearTimeout(timeout);
            }

            // Add file to internal changed files array
            if (!files.includes(path)) {
                files.push(path);
            }

            // Update timeout
            timeout = setTimeout(() => {
                console.log('Change in javascript detected');
                // Copy files to build in another array
                const buildFiles = [...files];
                // Call method
                gulp.series((callback) => buildJS(buildFiles, type, config, callback))();
                // Reset internal changed files array
                files = [];
            }, 1000);
        })
    ;
};

module.exports.buildJS = buildJS;