nhentai-js/nhentai.js

nHentai wrapper for Javascript

const request = require('superagent');
const cheerio = require('cheerio');
const tagSpacerPatternn = /(\([0-9,]+\))([a-zA-Z])/g;
const tagSplitPattern = /(?<=\))\s(?=[a-zA-Z])/;

const urlToId = /(https?:\/\/nhentai\.net\/g\/)(\d+)\/?.*/;
const gToId = /\/g\/(\d+)\//;
const hrefToPage = /(&||\?)page=(\d+)/;
const doubleSlashToHttps = /(https:)?(\/\/)/;
const styleToAspectRatio = /padding:0 0 (.*)% 0/;
const resultsToInt = /(.*) Results/i;

class nHentai {
    static getDoujin(identifier) {
        const id = identifier.replace(urlToId, '$2');
        return new Promise((resolve, reject) => {
            request
                .get('https://nhentai.net/g/' + id + '/')
                .then(res => {
                    const $ = cheerio.load(res.text);
                    let details = {};
                    $('.tag-container.field-name').find('.count').each(function () {
                        const el = $(this);
                        el.text(` (${el.text()}) `);
                    });
                    $('.tag-container.field-name').text().split('\n').map(string => string.trim()).filter(u => u).map((tag, i, tags) => {
                        if (tag.endsWith(':') && !tags[i + 1].endsWith(':')) {
                            details[tag.substring(0, tag.length - 1).toLowerCase()] = tags[i + 1].replace(tagSpacerPatternn, '$1 $2').split(tagSplitPattern);
                        }
                    });
                    const title = $('#info').find('h1').text();
                    const nativeTitle = $('#info').find('h2').text();
                    const thumbnails = Object.entries($('.gallerythumb').find('img')).map(image => {
                        return image[1].attribs
                            ? image[1].attribs['data-src']
                            : null;
                    }).filter(link => link);
                    const images = Object.entries($('.gallerythumb').find('img')).map(image => {
                        return image[1].attribs
                            ? image[1].attribs['data-src'].replace(/t(\.(jpg|png|gif))/, '$1').replace('t.nhentai', 'i.nhentai')
                            : null;
                    }).filter(link => link);
                    const link = `https://nhentai.net/g/${id}/`;
                    resolve({ title, nativeTitle, details, pages: images, thumbnails, link });
                })
                .catch(reject);
        });
    }

    static getHomepage(page = 1) {
        return new Promise((resolve, reject) => {
            if (page <= 0) {
                reject(new Error('Page must be greater than or equal to 1'));
                return;
            }

            request
                .get('https://nhentai.net/?page=' + page)
                .then(res => {
                    const $ = cheerio.load(res.text);
                    let details = [];
                    let selector = $('.gallery').children('a');
                    Object.keys(selector).map(key => {
                        if (parseInt(key)) {
                            let bookdetails = {};
                            let book = selector[key];
                            let img = findObject(book.children, 'name', 'img');
                            bookdetails.bookId = book.attribs.href.replace(gToId, '$1');
                            bookdetails.thumbnailAspectRatio = book.attribs.style.replace(styleToAspectRatio, '$1');
                            if ('is' in img.attribs) {
                                bookdetails.thumbnail = img.attribs['data-src'];
                            } else {
                                bookdetails.thumbnail = img.attribs['src'].replace(doubleSlashToHttps, 'https://');
                            }
                            bookdetails.title = findObject(book.children, 'name', 'div').children[0].data;
                            details.push(bookdetails);
                        }
                    })
                    resolve({
                        results: details,
                        lastPage: $('.last')[0] ? $('.last')[0].attribs.href.match(hrefToPage)[2] : page
                    });
                })
                .catch(reject);
        });
    }

    static search(query, page = 1, sort = 'date') {
        return new Promise((resolve, reject) => {

            if (!query) {
                reject(new Error('Query cannot be empty'));
                return;
            }

            if (page <= 0) {
                reject(new Error('Page must be greater than or equal to 1'));
                return;
            }

            const sortMethod = sort.toLowerCase();

            if (!['popular', 'date'].includes(sortMethod)) {
                reject(new Error('Invalid sorting'));
            }

            request
                .get('https://nhentai.net/search/')
                .query({
                    q: query,
                    page,
                    sort: sort.toLowerCase()
                })
                .then(res => {
                    const $ = cheerio.load(res.text);
                    let details = [];
                    let selector = $('.gallery').children('a');
                    Object.keys(selector).map(key => {
                        if (parseInt(key)) {
                            let bookdetails = {};
                            let book = selector[key];
                            let img = findObject(book.children, 'name', 'img');
                            bookdetails.bookId = book.attribs.href.replace(gToId, '$1');
                            bookdetails.thumbnailAspectRatio = book.attribs.style.replace(styleToAspectRatio, '$1');
                            if ('is' in img.attribs) {
                                bookdetails.thumbnail = img.attribs['data-src'];
                            } else {
                                bookdetails.thumbnail = img.attribs['src'].replace(doubleSlashToHttps, 'https://');
                            }
                            bookdetails.title = findObject(book.children, 'name', 'div').children[0].data;
                            details.push(bookdetails);
                        }
                    });

                    let numberOfResults = findObject($('#content')[0].children, 'name', 'h2').children[0].data.match(resultsToInt)[1].split(',').join('');
                    if (parseInt(numberOfResults)) {
                        numberOfResults = parseInt(numberOfResults);
                    } else {
                        numberOfResults = 0;
                    }
                    resolve({
                        results: details,
                        lastPage: $('.last')[0] ? $('.last')[0].attribs.href.match(hrefToPage)[2] : page,
                        totalSearchResults: numberOfResults
                    });
                })
                .catch(reject);
        })
    }

    static exists(identifier) {
        const id = identifier.replace(urlToId, '$2');
        return new Promise((resolve, reject) => {
            request
                .head('https://nhentai.net/g/' + id + '/')
                .then(res => resolve(true))
                .catch(err => {
                    resolve(false);
                });
        });
    }
}

function findObject(obj, key, value) {
    const found = Object.entries(obj).filter(object => object[1][key] === value)[0];
    if (!found) { return null; }
    return found[1];
}

module.exports = nHentai;