const cheerio = require('cheerio');
const ProcessImage = ($, e, c, noscript = false) => {
    const img = $(e).find(c);

    if (img.length > 0) {
        let message;
        // special handling for img wrapped in <noscript>
        if (noscript) {
            // eslint-disable-next-line no-unused-vars
            const i = cheerio.load(img[0].children[0].data)('img')[0];

            message = `<figure><img alt='${i.attribs.alt}' src='${i.attribs.src}'><br><figcaption>`;
        } else {
            if (img[0].attribs.src) {
                // handle cover image and lazy-loading images
                message = `<figure><img alt='${img[0].attribs.alt ? img[0].attribs.alt : ''}' src='${img[0].attribs.src.replace(/(?<=\/news\/).*?(?=\/cpsprodpb)/, '600')}'><br><figcaption>`;
            } else {
                message = `<figure><img alt='${img[0].attribs['data-alt'] ? img[0].attribs['data-alt'] : ''}' src='${img[0].attribs['data-src'].replace(/(?<=\/news\/).*?(?=\/cpsprodpb)/, '600')}'><br><figcaption>`;
            }

            // add image caption
            const figcaption = $(e).find('.media-caption__text');
            if (figcaption.length > 0) {
                message += `${$(figcaption[0]).text().trim()}`;
            }

            // add image copyright
            const copyright = $(e).find('.story-image-copyright');
            if (copyright.length > 0) {
                message += ` ©${$(copyright[0]).text().trim()}`;
            }
        }

        message += '</figcaption></figure>';

        $(message).insertAfter(e);
    }
};

const ProcessVideo = ($, e, c) => {
    const video = $(e).find(c);

    video.each((i, f) => {
        const cover = $(f).children('img.player-with-placeholder__image');
        if (cover.length > 0) {
            $(cover[0]).insertBefore(e);
        }
        const link = $(f).find('figure.js-media-player-unprocessed');
        if (link.length > 0) {
            const url = JSON.parse(link[0].attribs['data-playable']).settings.externalEmbedUrl;
            const message = `<br><a href='${url}'>使用浏览器播视频/view video in browser</a>`;
            $(message).insertAfter(e);
        }
    });
};

const ProcessAVFeed = ($) => {
    const content = $('div.vxp-media__summary');

    const video = $('div.vxp-media__player');

    video.each((i, e) => {
        const cover = $(e).children('img.vxp-media__placeholder-image');
        if (cover.length > 0) {
            $(cover[0]).insertBefore(content[0].firstChild);
        }
        const link = $(e).find('figure.js-media-player-unprocessed');
        if (link.length > 0) {
            const url = JSON.parse(link[0].attribs['data-playable']).settings.externalEmbedUrl;
            const message = `<br><a href='${url}'>使用浏览器播视频/view video in browser</a>`;
            $(message).insertAfter(content[0].firstChild);
        }
    });

    return content.html();
};

const ProcessFeed = ($, link) => {
    // by default treat it as a hybrid news with video and story-body__inner
    let content = $('div.story-body__inner');

    if (content.length === 0) {
        // it's a video news with video and story-body
        content = $('div.story-body');
    }

    if (content.length === 0) {
        // chinese version has different structure
        content = $('main[role="main"]');
    }

    // remove useless DOMs
    content.find('div.bbccom_slot, .off-screen, .embed-report-link').each((i, e) => {
        $(e).remove();
    });

    if ($('#comp-media-player').length > 0) {
        // there is a cover video

        let message = `<br><a href='${link}'>使用浏览器播视频/view video in browser</a>`;

        const cover = $('#comp-media-player').find('img.player-with-placeholder__image');

        if (cover.length > 0) {
            // there is a cover image
            message = `<br><img src='${cover[0].attribs.src}'>` + message;
        }

        $(message).insertAfter(content[0].lastChild);
    }

    // resize all images and videos
    content.find('figure').each((i, e) => {
        ProcessImage($, e, '.image-and-copyright-container > img');

        // handle lazy-loading images
        ProcessImage($, e, '.js-delayed-image-load');

        ProcessImage($, e, 'div > div > div > img');

        ProcessImage($, e, 'div > div > div > noscript', true);

        ProcessVideo($, e, 'figure.media-with-caption > div.player-with-placeholder');

        $(e).remove();
    });

    return content.html();
};

module.exports = {
    ProcessFeed,
    ProcessAVFeed,
};