const fs = require('fs')
const path = require('path')

const cp = require('child_process')
const process = require('process')
//const exec = cp.execSync
const exec = (cmd) => {
    console.log(`Exec: ${cmd}`)
    return cp.execSync(cmd)
}

const CleanCSS = require('clean-css')
const html = require('html-minifier')


const red    = '\033[1;31m'
const green  = '\033[1;32m'
const yellow = '\033[1;33m'
const blue   = '\033[1;34m'

const bold  = '\033[1m'
const reset = '\033[0m'


const minjs   = 'script.min.js'
const mincss  = 'style.min.css'


main()


function main() {
    switch (process.argv[2]) {

        case 'build':
            const dir = process.argv[3]
            if (dir)
                buildOne(dir)
            else
                buildAll()
            break

        case 'archive':
            archive()
            break

        case 'clean':
            clean()
            break

        default:
            print('Available actions:', true)
            printList([
                'build',
                'build <dir>',
                'archive',
                'clean',
            ])
            break
    }
}


function buildAll() {

    const dirs = fs.readdirSync('.', {
        withFileTypes: true
    })
    .filter(file => file.isDirectory())
    .map(file => file.name)

    const pages = [
        '.',
        ...dirs,
    ]

    for (let page of pages)
        buildOne(page)

    print('Completed', true, 'V', green)
}

function buildOne(dir) {

    print(`${bold}Building:${reset} ${dir}`)

    const config = `${dir}/webpage.json`
    let files
    if (fs.existsSync(config)) {
        files = JSON.parse(fs.readFileSync(config))
    }
    else {
        print(
            'Unable to find webpage.json, skipping',
            false, '!', yellow,
        )
        return
    }

    fs.mkdirSync(`dist/${dir}`, {
        recursive: true
    })

    print('Minifying JS')
    minifyJs(dir, files)
    print('Rendering LESS')
    renderLess(dir, files)
    print('Minifying CSS')
    minifyCss(dir, files)
    print('Converting paths in HTML')
    convertPathsHtml(dir, files)
    print('Minifying HTML')
    minifyHtml(dir, files)
    print('Copying other files')
    copyOther(dir, files)
}

function minifyJs(dir, files) {
    files.js = files.js || []
    if (files.js.length == 0) return;
    exec(
        'node_modules/.bin/terser --compress --mangle ' +
        `-o "dist/${dir}/${minjs}" ` +
        files.js.map(js => `"${dir}/${js}"`).join(' ')
    )
}

function renderLess(dir, files) {
    files.less = files.less || []
    if (files.less.length == 0) return;
    rendered = path.resolve(`dist/${dir}/${mincss}`)
    exec(
        'node_modules/.bin/lessc ' +
        files.less.map(less => `"${dir}/${less}"`).join(' ') +
        ` "${rendered}"`
    )
    files.css = [
        ...(files.css || []),
        rendered,
    ]
}

function minifyCss(dir, files) {
    files.css = files.css || []
    if (files.css.length == 0) return;
    const content = new CleanCSS().minify(files.css).styles
    fs.writeFileSync(`dist/${dir}/${mincss}`, content)
}

function convertPathsHtml(dir, files) {
    const scriptRegex = /(?:<script src=['"]?js\/\w+\.js['"]?><\/script>[\s\r\n]*)+/gm
    const converted = []
    files.html = files.html || []
    for (let file of files.html) {
        const content = fs.readFileSync(`${dir}/${file}`)
            .toString()
            .replace(
                '<script src="https://cdn.jsdelivr.net/npm/less"></script>',
                ''
            )
            .replace(
                '<link rel="stylesheet/less" type="text/css" href="styles.less" />',
                `<link rel="stylesheet" href="${mincss}" />`
            )
            .replace(
                scriptRegex,
                `<script src="${minjs}"></script>`
            )
        const built = path.resolve(`dist/${dir}/${file}`)
        fs.writeFileSync(built, content)
        converted.push(built)
    }
    files.html = converted
}

function minifyHtml(dir, files) {
    files.html = files.html || []
    for (let file of files.html) {
        const isAbs = path.isAbsolute(file)
        const name  = (isAbs ? file : `${dir}/${file}`)
        const built = (isAbs ? file : `dist/${dir}/${file}`)
        const content = html.minify(
            fs.readFileSync(name).toString(),
            {
                collapseBooleanAttributes: true,
                collapseInlineTagWhitespace: true,
                collapseWhitespace: true,
                removeAttributeQuotes: true,
                removeComments: true,
                removeScriptTypeAttributes: true,
                removeStyleLinkTypeAttributes: true,
                useShortDoctype: true,
                keepClosingSlash: false,
            }
        )
        fs.writeFileSync(built, content)
    }
}

function copyOther(dir, files) {
    files.other = files.other || []
    for (let file of files.other) {
        const isAbs = path.isAbsolute(file)
        const name  = (isAbs ? file : `${dir}/${file}`)
        const built = (isAbs ? file : `dist/${dir}/${file}`)
        fs.cpSync(name, built, {
            recursive: true,
            errorOnExist: false,
        })
    }
}


function archive() {
    exec('7z a dist.zip dist/*')
}

function clean() {
    fs.rmSync('dist/', {
        recursive: true,
        force: true,
    })
    fs.rmSync('dist.zip', {
        force: true,
    })
}


function print(
    str,
    title = false,
    symbol = '*',
    color = blue,
) {
    console.log(
        `${color}[${symbol}]${reset} ` +
        `${title ? bold : ""}${str}${reset}`
    )
}

function printList(arr) {
    for (let item of arr)
        console.log(`    ${item}`)
}