const axios = require("axios");
const cheerio = require('cheerio');
const Promise = require('bluebird')
const _ = require('lodash');
var CryptoJS = require("crypto-js");
const fs = require('fs')
const download = require('../../utils/imagedownload/index');
async function DownloadNgonPhong(link) {
    let resp = await axios.get(link);
    console.log("Get data manga done")
    resp = resp.data;
    const $ = cheerio.load(resp);
    let allChapterLink = [];
    let chapterTable = $(`body > section > div.info > div > div > div.m-b-0 > div.table-wrapper.chapter-table > table > tbody > tr`);
    for (let i = 1; i <= chapterTable.length; i++) {
        let currentChapter = $(`body > section > div.info > div > div > div.m-b-0 > div.table-wrapper.chapter-table > table > tbody > tr:nth-child(${i}) > td:nth-child(1) > a > span.hidden-sm.hidden-xs`);
        let currentChapterName = currentChapter.html();
        if (currentChapterName) {
            currentChapterName = currentChapterName.split(" ");
            currentChapterName = currentChapterName[currentChapterName.length -1]
            let currentChapterNumber = parseFloat(currentChapterName);
            let selectorChapterLink = $(`body > section > div.info > div > div > div.m-b-0 > div.table-wrapper.chapter-table > table > tbody > tr:nth-child(${i}) > td:nth-child(1) > a`);
            let currentChapterHref = selectorChapterLink.attr('href')
            allChapterLink.push({
                currentChapterName, currentChapterNumber, currentChapterHref
            })
        }
    }
    allChapterLink.reverse();
    console.log(`Có tổng cộng ${allChapterLink.length} chapter`)
    let mangaName = link.split("/");
    mangaName = mangaName[mangaName.length - 2];
    let outDir = `output/ngonphong-${mangaName}/`;
    console.log("Tên folder chứa ảnh: ", outDir)
    if (!fs.existsSync(outDir)) {
        fs.mkdirSync(outDir);
    }
    let chapterImageLinkFile = outDir + "images.txt";
    if (!fs.existsSync(chapterImageLinkFile)) {
        fs.writeFileSync(chapterImageLinkFile, "")
    }
    let imageLinksFile = fs.readFileSync(outDir + "images.txt");
    imageLinksFile = imageLinksFile.toString();
    let chapterToGetImages = [];
    if (imageLinksFile.length !== 0) {
        let alreadyHaveImageLinkChap = JSON.parse(imageLinksFile);
        //Check xem trong file có chapter nào rồi thì bỏ qua chapter đó
        // Chỉ get link ảnh ở những chapter chưa có link
        allChapterLink.map(each => {
            let isDownloaded = false;
            alreadyHaveImageLinkChap.map(ae => {
                if (each.currentChapterNumber === ae.chapter) {
                    isDownloaded = true
                }
            })
            if (isDownloaded === false) {
                chapterToGetImages.push(each)
            }
        })
    } else {
        chapterToGetImages = allChapterLink;
    }

    console.log(`Có ${chapterToGetImages.length} chapter chưa lấy ảnh`);
    let allChapterChunk = _.chunk(chapterToGetImages, 3);
    let allImageInEachChapter;
    if (imageLinksFile.length !== 0) {
        let alreadyHaveImageLinkChap = JSON.parse(imageLinksFile);
        allImageInEachChapter = alreadyHaveImageLinkChap;
    } else {
        allImageInEachChapter = []
    }

    let chapterIndex = 1;
    await Promise.each(allChapterChunk, async (eachChapterChunk, index) => {
        console.log(`Current chunk: ${index}/${allChapterChunk.length} - ${eachChapterChunk.length} items`)
        let downloadChapterRequest = [];
        eachChapterChunk.map(each => {
            downloadChapterRequest.push(axios.get(each.currentChapterHref))
        })
        let downloadChapterResult = await Promise.all(downloadChapterRequest);
        downloadChapterResult = downloadChapterResult.map(each => {
            return each.data
        })

        console.log(`Downloaded chunk: ${index}/${allChapterChunk.length}`)
        downloadChapterResult.map(async (each, cIndex) => {
            console.log(`Downloading Chapter ${chapterIndex}/${chapterToGetImages.length}`)
            let chapterDetail = cheerio.load(each);
            let chapterContentSelector = chapterDetail('#view-chapter')
            let chapterContentText = chapterContentSelector.html();
            let htmlContent = chapterContentText.match(/var htmlContent=(.*);/);
            let jsonContent = JSON.parse(JSON.parse(htmlContent[1]));
            const passphrase = '@9jriuQ^@'+'~4ZoLils*'+'^u$UxZ!Qzy<ytt_Z2}'
            var encrypted = jsonContent.ciphertext;
            var salt = CryptoJS.enc.Hex.parse(jsonContent.salt);
            var iv = CryptoJS.enc.Hex.parse(jsonContent.iv);
            var key = CryptoJS.PBKDF2(passphrase, salt, {
                hasher: CryptoJS.algo.SHA512,
                keySize: 64 / 8,
                iterations: 999
            });
            var decrypted = CryptoJS.AES.decrypt(encrypted, key, {
                iv: iv
            });
            let decryptedStr = decrypted.toString(CryptoJS.enc.Utf8);
            decryptedStr = decryptedStr.replace(/@9jriuQ\^@/g, '.');
            decryptedStr = decryptedStr.replace(/~4ZoLils\*/g, ':');
            decryptedStr = decryptedStr.replace(/\^u\$UxZ!Qzy<ytt_Z2}/g, '/');
            let chapterHtml = cheerio.load(decryptedStr);
            let chapterImgs = []
            chapterHtml('img').map((index, el) => {
                let imageLink = chapterHtml(el).attr('data-9jriuq');
                chapterImgs.push(imageLink)
            });
            allImageInEachChapter.push({
                chapter: eachChapterChunk[cIndex].currentChapterNumber,
                images: chapterImgs
            })
            fs.writeFileSync(chapterImageLinkFile, JSON.stringify(allImageInEachChapter))
            chapterIndex++;
        })
    })
    console.log("Đã lấy xong link ảnh")
    // Chia ảnh thành 2 loại tải nhanh và tải chậm

    await Promise.each(allImageInEachChapter, async eachChapter => {
        console.log("Bắt đầu tải ảnh chapter ", eachChapter.chapter)
        let tempOutDir = outDir + eachChapter.chapter;
        if (!fs.existsSync(tempOutDir)) {
            fs.mkdirSync(tempOutDir);
        }
        // Check ảnh, nếu ảnh tải nhanh được thì tải 1 phát hết
        // Nếu ảnh ko tải nhanh được thì tải từng cái một
        let fastDownloadUrls = [];
        let slowDownloadUrls = [];
        for (let i = 0; i < eachChapter.images.length; i++) {
            let fileDest = `${tempOutDir}/${i}.jpg`;
            if (!fs.existsSync(fileDest)) {

                let headers = {
                    'Connection': 'keep-alive',
                    'Cache-Control': 'max-age=0',
                    'Upgrade-Insecure-Requests': '1',
                    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.77 Safari/537.36',
                    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9',
                    'Accept-Language': 'en-GB,en;q=0.9,en-US;q=0.8,vi;q=0.7'
                }
                if (eachChapter.images[i].includes("proxy/view.php?url=")) {
                    eachChapter.images[i] = eachChapter.images[i].split("proxy/view.php?url=")[1];
                } else {
                    headers["referer"] = "https://www.ocumeo.com/"
                }
                const options = {
                    url: eachChapter.images[i],
                    dest: `${tempOutDir}/${i}.jpg`,
                    headers: headers
                }
                if (options.url.includes("blogspot.com")) {
                    fastDownloadUrls.push(options)
                } else {
                    slowDownloadUrls.push(options)
                }
            }
        }
        if (fastDownloadUrls.length > 0) {
            // Với ảnh tải nhanh được thì tải song song
            console.log("Đang tải ảnh có tốc độ cao")
            fastDownloadUrls = _.chunk(fastDownloadUrls, 10); // Ảnh tải được liên tục thì tải 1 lúc 10 cái
            await Promise.each(fastDownloadUrls, async (eachChunk, index) => {
                console.log(`Đang tải ảnh tốc độ cao chunk ${index}/${fastDownloadUrls.length}`)
                let downloadRequest = [];
                eachChunk.map(e => {
                    downloadRequest.push(download.image(e))
                })
                await Promise.all(downloadRequest)
            })
        }
        if (slowDownloadUrls.length > 0) {
            console.log("Đang tải những ảnh có tốc độ chậm")
            slowDownloadUrls = _.chunk(slowDownloadUrls, 2); // Ảnh chậm thì tải 1 lúc 2 cái
            await Promise.each(slowDownloadUrls, async (eachChunk, index) => {
                console.log(`Đang tải ảnh có tốc độ chậm chunk ${index}/${slowDownloadUrls.length} - Chapter ${eachChapter.chapter}`);
                let downloadRequest = [];
                eachChunk.map(e => {
                    downloadRequest.push(download.image(e))
                })
                await Promise.all(downloadRequest)
            })
        }
    })
    console.log("Đã tải xong toàn bộ ảnh")
    return allImageInEachChapter
}

module.exports = {
    DownloadNgonPhong
}