const axios = require("axios");
const cheerio = require('cheerio');
const Promise = require('bluebird')
const _ = require('lodash');
const fs = require('fs')
const download = require('../../utils/imagedownload/index');

async function DownloadNettruyentop(link) {
    let mangaName = link.split("/");
    mangaName = mangaName[mangaName.length - 1];
    let mangaId = mangaName.split("-");
    mangaId = mangaId[mangaId.length - 1];
    console.log({mangaName, mangaId});
    let allChapterLinks = [];
    let chapterData = await axios.get(`http://www.nettruyentop.com/Comic/Services/ComicService.asmx/ProcessChapterPreLoad?comicId=${mangaId}&commentId=-1`);
    chapterData = chapterData.data;
    if (chapterData.success) {
        chapterData = chapterData.chapters;
        allChapterLinks = chapterData.map(e => {
            let _temp = e.url.split("/");
            _temp = _temp[_temp.length - 2].split("-")[1];
            e.chapter = parseFloat(_temp);
            e.url = "http://www.nettruyentop.com" + e.url
            return e
        })
    } else {
        console.log("Không lấy được danh sách chap qua API, tiến hành lấy HTML")
        let chapterData = await axios.get(link);
        chapterData = chapterData.data;
        chapterData = cheerio.load(chapterData);
        let chapterTable = chapterData('#nt_listchapter > nav > ul > li')
        for (let i=1; i<=chapterTable.length;i++) {
            let aSelector = chapterData(`#nt_listchapter > nav > ul > li:nth-child(${i+1}) > div.col-xs-5.chapter > a`);
            if (aSelector.attr('href')) {
                allChapterLinks.push({
                    url: aSelector.attr('href'),
                    name: aSelector.text(),
                    chapter: parseFloat(aSelector.text().split(" ")[1])
                })
            }
        }
    }
    allChapterLinks.reverse();
    console.log(`Có tổng cộng ${allChapterLinks.length} chapter`)
    let outDir = `output/nettruyentop-${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 downloadedChapter = JSON.parse(imageLinksFile);
        allChapterLinks.map(each => {
            let isDownloaded = false;
            downloadedChapter.map(ae => {
                if (each.chapter === ae.chapter) {
                    isDownloaded = true
                }
            })
            if (isDownloaded === false) {
                chapterToGetImages.push(each)
            }
        })
    } else {
        chapterToGetImages = allChapterLinks;
    }
    console.log(`Còn ${chapterToGetImages.length} chapter chưa lấy ảnh`)
    let allChapterChunk = _.chunk(chapterToGetImages, 2);
    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: ${index + 1}/${allChapterChunk.length} - ${eachChapterChunk.length} items`)
        let downloadChapterRequest = [];
        eachChapterChunk.map(each => {
            downloadChapterRequest.push(axios.get(each.url))
        })
        let downloadChapterResult = await Promise.all(downloadChapterRequest);
        downloadChapterResult = downloadChapterResult.map(each => {
            return each.data
        })
        console.log(`Downloaded chunk: ${index + 1}/${allChapterChunk.length}`)
        downloadChapterResult.map(async (each, cIndex) => {
            console.log(`Analyzing Chapter ${chapterIndex}/${allChapterChunk.length}`)
            let chapterDetail = cheerio.load(each);
            let imageBox = chapterDetail('.reading-detail > div')
            let totalImage = imageBox.length;
            let chapterImgs = [];
            for (let i = 1; i <= totalImage; i++) {
                let imageSelector = chapterDetail(`#page_${i} > img`);
                chapterImgs.push(imageSelector.attr('src'))
            }
            chapterIndex++;
            allImageInEachChapter.push({
                chapterId: eachChapterChunk[cIndex].chapterId,
                name: eachChapterChunk[cIndex].name,
                url: eachChapterChunk[cIndex].url,
                chapter: eachChapterChunk[cIndex].chapter,
                images: chapterImgs
            })
            await fs.writeFileSync(chapterImageLinkFile, JSON.stringify(allImageInEachChapter))
        })
    })

    imageLinksFile = fs.readFileSync(outDir + "images.txt");
    allImageInEachChapter = JSON.parse(imageLinksFile.toString());
    console.log("Đã lấy xong link ảnh")
    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);
        }
        let downloadUrls = [];
        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',
                    "Referer": "http://www.nettruyentop.com/"
                }
                if (!eachChapter.images[i].startsWith("http")) {
                    eachChapter.images[i] = "http://"+eachChapter.images[i].slice(2, eachChapter.images[i].length);
                }
                const options = {
                    url: eachChapter.images[i],
                    dest: fileDest,
                    headers: headers
                }
                downloadUrls.push(options)
            }
        }
        downloadUrls = _.chunk(downloadUrls, 5);
        await Promise.each(downloadUrls, async (eachChunk, index) => {
            console.log(`Đang tải ảnh có tốc độ chậm chunk ${index+1}/${downloadUrls.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 = {
    DownloadNettruyentop
}