'use strict';

const { JSDOM } = require('jsdom');
const moment = require('moment');
const http = require('./http');

function trim(str) {
    if (!str) return null;
    return str.trim().replace(/\s+/g, ' ');
}

function extractDate(dateString, format, match) {
    if (match) {
        const dateStamp = trim(dateString).match(match);

        if (dateStamp) {
            const dateValue = moment.utc(dateStamp[0], format);

            return dateValue.isValid() ? dateValue.toDate() : null;
        }
        return null;
    }

    const dateValue = moment.utc(trim(dateString), format);

    return dateValue.isValid() ? dateValue.toDate() : null;
}

function formatDate(dateValue, format, inputFormat) {
    if (inputFormat) {
        return moment(dateValue, inputFormat).format(format);
    }

    return moment(dateValue).format(format);
}

function prefixProtocol(urlValue, protocol = 'https') {
    if (protocol && /^\/\//.test(urlValue)) {
        return `${protocol}:${urlValue}`;
    }

    return urlValue;
}

function q(context, selector, attrArg, applyTrim = true) {
    const attr = attrArg === true ? 'textContent' : attrArg;

    if (attr) {
        const value = selector
            ? context.querySelector(selector)?.[attr] || context.querySelector(selector)?.attributes[attr]?.value
            : context[attr] || context[attr]?.attributes[attr]?.value;

        return applyTrim && value ? trim(value) : value;
    }

    return selector ? context.querySelector(selector) : context;
}

function all(context, selector, attrArg, applyTrim = true) {
    const attr = attrArg === true ? 'textContent' : attrArg;

    if (attr) {
        return Array.from(context.querySelectorAll(selector), el => (applyTrim && el[attr] ? trim(el[attr]) : el[attr]));
    }

    return Array.from(context.querySelectorAll(selector));
}

function exists(context, selector) {
    return !!q(context, selector);
}

function html(context, selector) {
    const el = q(context, selector, null, true);

    return el && el.innerHTML;
}

function texts(context, selector, applyTrim = true, filter = true) {
    const el = q(context, selector, null, applyTrim);
    if (!el) return null;

    const nodes = Array.from(el.childNodes)
        .filter(node => node.nodeName === '#text')
        .map(node => (applyTrim ? trim(node.textContent) : node.textContent));

    return filter ? nodes.filter(Boolean) : nodes;
}

function text(context, selector, applyTrim = true) {
    const nodes = texts(context, selector, applyTrim, true);
    if (!nodes) return null;

    const textValue = nodes.join(' ');

    return applyTrim ? trim(textValue) : textValue;
}

function meta(context, selector, attrArg = 'content', applyTrim = true) {
    if (/meta\[.*\]/.test(selector)) {
        return q(context, selector, attrArg, applyTrim);
    }

    return q(context, `meta[${selector}]`, attrArg, applyTrim);
}

function date(context, selector, format, match, attr = 'textContent') {
    const dateString = q(context, selector, attr, true);

    if (!dateString) return null;

    return extractDate(dateString, format, match);
}

function image(context, selector = 'img', attr = 'src', protocol = 'https') {
    const imageEl = q(context, selector, attr);

    // no attribute means q output will be HTML element
    return attr ? prefixProtocol(imageEl, protocol) : imageEl;
}

function images(context, selector = 'img', attr = 'src', protocol = 'https') {
    const imageEls = all(context, selector, attr);

    return attr ? imageEls.map(imageEl => prefixProtocol(imageEl, protocol)) : imageEls;
}

function url(context, selector = 'a', attr = 'href', protocol = 'https') {
    const urlEl = q(context, selector, attr);

    return attr ? prefixProtocol(urlEl, protocol) : urlEl;
}

function urls(context, selector = 'a', attr = 'href', protocol = 'https') {
    const urlEls = all(context, selector, attr);

    return attr ? urlEls.map(urlEl => prefixProtocol(urlEl, protocol)) : urlEls;
}

function poster(context, selector = 'video', attr = 'poster', protocol = 'https') {
    const posterEl = q(context, selector, attr);

    return attr ? prefixProtocol(posterEl, protocol) : posterEl;
}

function video(context, selector = 'source', attr = 'src', protocol = 'https') {
    const trailerEl = q(context, selector, attr);

    return attr ? prefixProtocol(trailerEl, protocol) : trailerEl;
}

function videos(context, selector = 'source', attr = 'src', protocol = 'https') {
    const trailerEls = all(context, selector, attr);

    return attr ? trailerEls.map(trailerEl => prefixProtocol(trailerEl, protocol)) : trailerEls;
}

function duration(context, selector, match, attr = 'textContent') {
    const durationString = q(context, selector, attr);

    if (!durationString) return null;
    const durationMatch = durationString.match(match || /(\d+:)?\d+:\d+/);

    if (durationMatch) {
        const segments = ['00'].concat(durationMatch[0].split(':')).slice(-3);

        return moment.duration(segments.join(':')).asSeconds();
    }

    return null;
}

const legacyFuncs = {
    q,
    qa: all,
    qall: all,
    qd: date,
    qdate: date,
    qh: html,
    qhtml: html,
    qi: image,
    qimage: image,
    qimages: images,
    qis: images,
    ql: duration,
    qlength: duration,
    qm: meta,
    qmeta: meta,
    qp: poster,
    qposter: poster,
    qs: all,
    qt: video,
    qtext: text,
    qtexts: texts,
    qtrailer: video,
    qtrailers: videos,
    qts: videos,
    qtx: text,
    qtxs: texts,
    qtxt: text,
    qtxts: texts,
    // qu: url,
    qurl: url,
    qurls: urls,
    qus: urls,
};

const quFuncs = {
    all,
    html,
    date,
    dur: duration,
    duration,
    exists,
    image,
    images,
    img: image,
    imgs: images,
    length: duration,
    meta,
    poster,
    q,
    text,
    texts,
    trailer: video,
    url,
    urls,
    video,
    videos,
};

function init(element, window) {
    if (!element) return null;

    const legacyContextFuncs = Object.entries(legacyFuncs) // dynamically attach methods with context
        .reduce((acc, [key, func]) => ({
            ...acc,
            [key]: (...args) => (window && args[0] instanceof window.HTMLElement // allow for different context
                ? func(...args)
                : func(element, ...args)),
        }), {});

    const quContextFuncs = Object.entries(quFuncs) // dynamically attach methods with context
        .reduce((acc, [key, func]) => ({
            ...acc,
            [key]: (...args) => (window && args[0] instanceof window.HTMLElement // allow for different context
                ? func(...args)
                : func(element, ...args)),
        }), {});

    return {
        element,
        el: element,
        html: element.outerHTML || element.body.outerHTML,
        text: trim(element.textContent),
        ...(window && {
            window,
            document: window.document,
        }),
        ...legacyContextFuncs,
        qu: quContextFuncs,
    };
}

function initAll(context, selector, window) {
    if (Array.isArray(context)) {
        return context.map(element => init(element, window));
    }

    return Array.from(context.querySelectorAll(selector))
        .map(element => init(element, window));
}

function extract(htmlValue, selector) {
    const { window } = new JSDOM(htmlValue);

    if (selector) {
        return init(window.document.querySelector(selector), window);
    }

    return init(window.document, window);
}

function extractAll(htmlValue, selector) {
    const { window } = new JSDOM(htmlValue);

    return initAll(window.document, selector, window);
}

async function get(urlValue, selector, headers, options, queryAll = false) {
    const res = await http.get(urlValue, headers);

    if (res.statusCode === 200) {
        const item = queryAll
            ? extractAll(res.body.toString(), selector)
            : extract(res.body.toString(), selector);

        return {
            item,
            items: all ? item : [item],
            res,
            ok: true,
            status: res.statusCode,
        };
    }

    return {
        item: null,
        items: [],
        res,
        ok: false,
        status: res.statusCode,
    };
}

async function getAll(urlValue, selector, headers, options) {
    return get(urlValue, selector, headers, options, true);
}

module.exports = {
    extractDate,
    extract,
    extractAll,
    init,
    initAll,
    formatDate,
    get,
    getAll,
    context: init,
    contextAll: initAll,
    ed: extractDate,
    ex: extract,
    exa: extractAll,
    fd: formatDate,
    parseDate: extractDate,
    ctx: init,
    ctxa: initAll,
    geta: getAll,
    qu: quFuncs,
    ...legacyFuncs,
};