// Create Table of Contents
let chapters = [];

// get chapter for navigation
function loadChapters(callback) {
    let sending = browser.runtime.sendMessage({
        msg: "getChapters"
    });
    return sending;
}

// Inject the Table of Contents
function createTOC() {
    let TOC = document.getElementById('toc') || document.createElement('nav'),
        headings = document.querySelectorAll('h1, h2, h3, h4, h5, h6');

    // fix headings
    for(let heading of headings) {
        heading.id = heading.parentNode.getAttribute('name');
    }

    TOC.id = 'toc';
    TOC.classList.add('toc', 'toc-right');
    TOC.innerHTML = '';

    document.body.insertBefore(TOC, document.body.childNodes[0]);

    tocbot.init({
        // Where to render the table of contents.
        tocSelector: '#toc',
        // Where to grab the headings to build the table of contents.
        contentSelector: 'body',
        // Which headings to grab inside of the contentSelector element.
        headingSelector: 'h2, h3',
        // smooth it out
        scrollSmooth: true
    });
}

function wrapInner(parent, wrapper, className) {
    if (typeof wrapper === "string")
        wrapper = document.createElement(wrapper);

    wrapper.classList.add(className);
    var div = parent.appendChild(wrapper);

    while(parent.firstChild !== wrapper)
        wrapper.appendChild(parent.firstChild);
}

function wrapPre() {
    for(let el of document.querySelectorAll('pre')) {
        wrapInner(el, 'code', 'lisp');
    }
}

// get the index of the currently viewed chapter
function findCurrentChapter() {
    let file = document.URL.split('/').pop().replace(/\#.*$/, '');
    let currentChapter = -1;
    for(let chapter in chapters) {
        if(chapters[chapter].url === file)
            currentChapter = chapter;
    }
    return parseInt(currentChapter);
}

// go to previous chapter
function goToPrevious() {
    if(!chapters) return;
    let currentChapter = findCurrentChapter();
    if(currentChapter > 0) {
        document.location.href =  chapters[currentChapter-1].url;
    }
}

// go to next chapter
function gotoNext() {
    if(!chapters) return;
    let currentChapter = findCurrentChapter();
    if(currentChapter < chapters.length - 1) {
        document.location.href =  chapters[currentChapter+1].url;
    }
}


// set up the navigation shortcuts
function setUpNav() {
    document.addEventListener('keypress', (event) => {
        switch(event.key) {
        case 'p':
            goToPrevious();
            break;
        case 'n':
            gotoNext();
            break;
        case 'h':
            document.location.href = 'index.html';
            break;
        }
    });
}

function setUpNumbering() {
    let chapter = findCurrentChapter();
    if (chapter >= 0) {
        document.documentElement.style['counter-reset'] = 'chapter ' + (chapter + 1);
    }
};

function collectFootnotes() {
    let footMap = [];

    // collect al footnotes into pairs
    for(let note of document.querySelectorAll('sup')) {
        let index = parseInt(note.innerText) - 1;

        // JS forces me to do that!
        if(!footMap[index])
            footMap[index] = {};

        footMap[index][note.parentElement.parentElement.classList.contains('notes') ?
                       'target' : 'origin'] = note;
    }

    return footMap;
}

function linkFootnotes() {
    function identifyAndLink(index, originid, targetid, origin, target) {
        origin.id = `foot${index}${originid}`;
        let link = document.createElement('a');
        target.id = `foot${index}${targetid}`;
        link.href = '#' + target.id;
        link.innerText = (index + 1);
        origin.innerHTML = '';
        origin.appendChild(link);
    };

    function createPopover(index, origin, target) {
        let content = target.parentElement.innerHTML;
        content = content.substring(`<sup>${index+1}</sup>`.length);
        if(target.parentElement && target.parentElement.nextSibling && target.parentElement.nextSibling.tagName !== 'P')
            content += '&hellip;';

        tippy(origin, { content, animateFill: false, animation: 'fade', theme: 'pcl'});
    }

    let footMap = collectFootnotes();

    for(let index in footMap) {
        index = parseInt(index); // I love you JavaScript :/
        let pair = footMap[index];
        if(pair && 'origin' in pair && 'target' in pair) {
            let origin = pair.origin;
            let target = pair.target;
            createPopover(index, origin, target);
            identifyAndLink(index, 1, 2, origin, target);
            identifyAndLink(index, 2, 1, target, origin);
        }
    }
}

// Let's apply that stuff.
loadChapters().then(newChapters => {
    chapters = newChapters;
    setUpNumbering();
});

linkFootnotes();
wrapPre();
HighlightLisp.highlight_auto();
HighlightLisp.paren_match();
createTOC();
setUpNav();