const {
    JSDOM
} = require("jsdom");
const fs = require("fs");

const showdown = require("showdown");
require("./showdown-prettify");
require("./showdown-footnotes");
const converter = new showdown.Converter({
    parseImgDimensions: true,
    headerLevelStart: 2,
    extensions: ["prettify", "footnotes"]
});

module.exports = function () {
    let folder = __dirname + "/../";
    createBlogPages(folder);

    fs.watchFile(folder + "blog/posts.json", function (curr, prev) {
        if (curr.mtime == prev.mtime)
            return;
        createBlogPages(folder);
    });
}

function createBlogPages(folder) {
    console.log("Refreshing blog sub-sites...");

    fs.readFile(folder + "index.html", function (_, data) {
        // set up the template
        let templateDom = new JSDOM(data);
        var templateDoc = templateDom.window.document;
        templateDoc.getElementById("main").innerHTML = "";
        let template = templateDom.serialize();

        fs.readFile(folder + "blog/posts.json", function (_, data) {
            let json = JSON.parse(data);
            for (let i = 0; i < json.length; i++) {
                let post = json[i];
                let id = post["id"];
                fs.readFile(folder + "blog/" + id + ".md", function (_, content) {
                    let dom = new JSDOM(template);
                    var document = dom.window.document;

                    document.title += " - " + post["name"];
                    document.querySelector('meta[property="og:title"]').setAttribute("content", post["name"]);
                    document.querySelector('meta[name="description"]').setAttribute("content", post["summary"]);
                    document.querySelector('meta[property="og:description"]').setAttribute("content", post["summary"]);

                    var nav = "";
                    nav += '<a class="nav-item nav-link" href="/#blog">Back to Main Page</a>';
                    nav += '<script src="scripts/blog-nav.js"></script>';
                    document.getElementById("nav-items").innerHTML = nav;

                    var c = "";
                    c += '<div class="list-display rounded">';
                    c += '<div class="blog-isolated">'
                    c += '<h1>' + post["name"] + '</h1>';
                    c += '<div id="blog-post-' + id + '">'
                    c += converter.makeHtml(content.toString());
                    c += '</div>';
                    c += '<span class="text-muted project-status blog-isolated-status">' + post["date"] + "</span>";
                    var discussLink = post["discuss"];
                    if (discussLink)
                        c += '<a href="' + discussLink + '" class="blog-discuss" id="blog-discuss-' + id + '">Discuss this post</a>'
                    c += '</div></div>';
                    document.getElementById("main").innerHTML = c;

                    let html = dom.serialize();
                    fs.writeFile(folder + "blog-" + id + ".html", html, function (_, _) {});
                });
            }
        });
    });
}