// ==========================================================================
// Gulp build script
// ==========================================================================
/* global require, __dirname */
/* eslint no-console: "off" */

var fs = require('fs');
var path = require('path');
var gulp = require('gulp');
var gutil = require('gulp-util');
var concat = require('gulp-concat');
var uglify = require('gulp-uglify');
var less = require('gulp-less');
var sass = require('gulp-sass');
var cleanCSS = require('gulp-clean-css');
var run = require('run-sequence');
var prefix = require('gulp-autoprefixer');
var svgstore = require('gulp-svgstore');
var svgmin = require('gulp-svgmin');
var rename = require('gulp-rename');
var s3 = require('gulp-s3');
var replace = require('gulp-replace');
var open = require('gulp-open');
var size = require('gulp-size');
var root = __dirname;

var paths = {
    plyr: {
        // Source paths
        src: {
            less: path.join(root, 'src/less/**/*'),
            scss: path.join(root, 'src/scss/**/*'),
            js: path.join(root, 'src/js/**/*'),
            sprite: path.join(root, 'src/sprite/*.svg'),
        },

        // Output paths
        output: path.join(root, 'dist/'),
    },
    demo: {
        // Source paths
        src: {
            less: path.join(root, 'demo/src/less/**/*'),
            js: path.join(root, 'demo/src/js/**/*'),
            sprite: path.join(root, 'demo/src/sprite/**/*'),
        },

        // Output paths
        output: path.join(root, 'demo/dist/'),

        // Demo
        root: path.join(root, 'demo/'),
    },
    upload: [path.join(root, 'dist/**'), path.join(root, 'demo/dist/**')],
};

// Task arrays
var tasks = {
    less: [],
    scss: [],
    js: [],
    sprite: [],
};

// Fetch bundles from JSON
var bundles = loadJSON(path.join(root, 'bundles.json'));
var package = loadJSON(path.join(root, 'package.json'));

// Load json
function loadJSON(path) {
    try {
        return JSON.parse(fs.readFileSync(path));
    } catch (err) {
        return {};
    }
}

var build = {
    js: function(files, bundle) {
        Object.keys(files).forEach(function(key) {
            var name = 'js-' + key;
            tasks.js.push(name);

            gulp.task(name, function() {
                return gulp
                    .src(bundles[bundle].js[key])
                    .pipe(concat(key))
                    .pipe(uglify())
                    .pipe(gulp.dest(paths[bundle].output));
            });
        });
    },
    less: function(files, bundle) {
        Object.keys(files).forEach(function(key) {
            var name = 'less-' + key;
            tasks.less.push(name);

            gulp.task(name, function() {
                return gulp
                    .src(bundles[bundle].less[key])
                    .pipe(less())
                    .on('error', gutil.log)
                    .pipe(concat(key))
                    .pipe(prefix(['last 2 versions'], { cascade: false }))
                    .pipe(cleanCSS())
                    .pipe(gulp.dest(paths[bundle].output));
            });
        });
    },
    scss: function(files, bundle) {
        Object.keys(files).forEach(function(key) {
            var name = 'scss-' + key;
            tasks.scss.push(name);

            gulp.task(name, function() {
                return gulp
                    .src(bundles[bundle].scss[key])
                    .pipe(sass())
                    .on('error', gutil.log)
                    .pipe(concat(key))
                    .pipe(prefix(['last 2 versions'], { cascade: false }))
                    .pipe(cleanCSS())
                    .pipe(gulp.dest(paths[bundle].output));
            });
        });
    },
    sprite: function(bundle) {
        var name = 'sprite-' + bundle;
        tasks.sprite.push(name);

        // Process Icons
        gulp.task(name, function() {
            return gulp
                .src(paths[bundle].src.sprite)
                .pipe(
                    svgmin({
                        plugins: [
                            {
                                removeDesc: true,
                            },
                        ],
                    })
                )
                .pipe(svgstore())
                .pipe(rename({ basename: bundle }))
                .pipe(gulp.dest(paths[bundle].output));
        });
    },
};

// Plyr core files
build.js(bundles.plyr.js, 'plyr');
build.less(bundles.plyr.less, 'plyr');
build.scss(bundles.plyr.scss, 'plyr');
build.sprite('plyr');

// Demo files
build.less(bundles.demo.less, 'demo');
build.js(bundles.demo.js, 'demo');
build.sprite('demo');

// Build all JS
gulp.task('js', function() {
    run(tasks.js);
});

// Build SCSS (for testing, default is LESS)
gulp.task('scss', function() {
    run(tasks.scss);
});

// Watch for file changes
gulp.task('watch', function() {
    // Plyr core
    gulp.watch(paths.plyr.src.js, tasks.js);
    gulp.watch(paths.plyr.src.less, tasks.less);
    gulp.watch(paths.plyr.src.sprite, tasks.sprite);

    // Demo
    gulp.watch(paths.demo.src.js, tasks.js);
    gulp.watch(paths.demo.src.less, tasks.less);
    gulp.watch(paths.demo.src.sprite, tasks.sprite);
});

// Default gulp task
gulp.task('default', function() {
    run(tasks.js, tasks.less, tasks.sprite, 'watch');
});

// Publish a version to CDN and demo
// --------------------------------------------

// Some options
var aws = loadJSON(path.join(root, 'aws.json'));
var version = package.version;
var maxAge = 31536000; // 1 year
var options = {
    cdn: {
        headers: {
            'Cache-Control': 'max-age=' + maxAge,
            Vary: 'Accept-Encoding',
        },
    },
    demo: {
        headers: {
            'Cache-Control': 'no-cache, no-store, must-revalidate, max-age=0',
            Vary: 'Accept-Encoding',
        },
    },
    symlinks: function(version, filename) {
        return {
            headers: {
                // http://stackoverflow.com/questions/2272835/amazon-s3-object-redirect
                'x-amz-website-redirect-location': '/' + version + '/' + filename,
                'Cache-Control': 'no-cache, no-store, must-revalidate, max-age=0',
            },
        };
    },
};

// If aws is setup
if ('cdn' in aws) {
    var regex =
        '(?:0|[1-9][0-9]*)\\.(?:0|[1-9][0-9]*).(?:0|[1-9][0-9]*)(?:-[\\da-z\\-]+(?:.[\\da-z\\-]+)*)?(?:\\+[\\da-z\\-]+(?:.[\\da-z\\-]+)*)?';
    var cdnpath = new RegExp(aws.cdn.domain + '/' + regex, 'gi');
    var semver = new RegExp('v' + regex, 'gi');
    var localPath = new RegExp('(../)?dist', 'gi');
    var versionPath = 'https://' + aws.cdn.domain + '/' + version;
}

// Publish version to CDN bucket
gulp.task('cdn', function() {
    console.log('Uploading ' + version + ' to ' + aws.cdn.domain + '...');

    // Upload to CDN
    return gulp
        .src(paths.upload)
        .pipe(
            size({
                showFiles: true,
                gzip: true,
            })
        )
        .pipe(
            rename(function(path) {
                path.dirname = path.dirname.replace('.', version);
            })
        )
        .pipe(replace(localPath, versionPath))
        .pipe(s3(aws.cdn, options.cdn));
});

// Publish to demo bucket
gulp.task('demo', function() {
    console.log('Uploading ' + version + ' demo to ' + aws.demo.domain + '...');

    // Replace versioned files in readme.md
    gulp
        .src([root + '/readme.md'])
        .pipe(replace(cdnpath, aws.cdn.domain + '/' + version))
        .pipe(gulp.dest(root));

    // Replace versioned files in plyr.js
    gulp
        .src(path.join(root, 'src/js/plyr.js'))
        .pipe(replace(semver, 'v' + version))
        .pipe(replace(cdnpath, aws.cdn.domain + '/' + version))
        .pipe(gulp.dest(path.join(root, 'src/js/')));

    // Replace local file paths with remote paths in demo HTML
    // e.g. "../dist/plyr.js" to "https://cdn.plyr.io/x.x.x/plyr.js"
    gulp
        .src([paths.demo.root + '*.html'])
        .pipe(replace(localPath, versionPath))
        .pipe(s3(aws.demo, options.demo));

    // Upload error.html to cdn (as well as demo site)
    return gulp
        .src([paths.demo.root + 'error.html'])
        .pipe(replace(localPath, versionPath))
        .pipe(s3(aws.cdn, options.demo));
});

// Open the demo site to check it's sweet
/*gulp.task("symlinks", function () {
    console.log("Updating symlinks...");

    return gulp.src(paths.upload)
        .pipe(through.obj(function (chunk, enc, callback) {
            if (chunk.stat.isFile()) {
                // Get the filename
                var filename = chunk.path.split("/").reverse()[0];

                // Create the 0 byte redirect files to upload
                createFile(filename, "")
                    .pipe(rename(function (path) {
                        path.dirname = path.dirname.replace(".", "latest");
                    }))
                    // Upload to S3 with correct headers
                    .pipe(s3(aws.cdn, options.symlinks(version, filename)));
            }

            callback(null, chunk);
        }));
});*/

// Open the demo site to check it's sweet
gulp.task('open', function() {
    console.log('Opening ' + aws.demo.domain + '...');

    // A file must be specified or gulp will skip the task
    // Doesn't matter which file since we set the URL above
    // Weird, I know...
    return gulp.src([paths.demo.root + 'index.html']).pipe(
        open('', {
            url: 'http://' + aws.demo.domain,
        })
    );
});

// Do everything
gulp.task('publish', function() {
    run(tasks.js, tasks.less, tasks.sprite, 'cdn', 'demo');
});