const uwuify = {
    // The prefix used in console messages
    CONSOLE_PREFIX: '[uwuify.js] ',
    // The range of time to wait between uwuification
    INTERVAL_MIN: 10000,
    INTERVAL_MAX: 60000,
    // Which characters to uwuify
    TARGET_REGEX: /[LRlr]+/g,
    // All the #text objects to modify
    TARGET_ELEMENTS: [],

    // Gets all #text elements on the page
    getTexts: function(object) {
        let res = [];

        for (let i = 0; i < object.childNodes.length; i++) {
            if (object.childNodes[i].nodeName == '#text') {
                res.push(object.childNodes[i]);
            } else {
                res = res.concat(uwuify.getTexts(object.childNodes[i]));
            }
        }

        return res;
    },

    // Generates a random integer between min and max
    getRandomInt: function (min, max) {
        const minCeiled = Math.ceil(min);
        const maxFloored = Math.floor(max);
        return Math.floor(Math.random() * (maxFloored - minCeiled) + minCeiled); // The maximum is exclusive and the minimum is inclusive
    },

    // Returns true if a string is able to be uwued
    isUwuable: function(string) {
        let res = Boolean(uwuify.TARGET_REGEX.exec(string));
        uwuify.TARGET_REGEX.lastIndex = 0
        return res;
    },

    // Uwuify a random target
    uwuify: function() {
        let targetIdx = uwuify.getRandomInt(0, uwuify.TARGET_ELEMENTS.length);

        let shifts = 0;
        let element = uwuify.TARGET_ELEMENTS[targetIdx]
        let text = element.textContent;
        while (!uwuify.isUwuable(text) && shifts < uwuify.TARGET_ELEMENTS.length) {
            shifts++;
            element = uwuify.TARGET_ELEMENTS[(targetIdx+shifts)%uwuify.TARGET_ELEMENTS.length];
            text = element.textContent;
        }

        if (!uwuify.isUwuable(text)) {
            console.info(`${uwuify.CONSOLE_PREFIX} No more text to uwuify.`);
            // Return from the function, preventing the next setTimeout().
            return
        }

        let matches = text.matchAll(uwuify.TARGET_REGEX).toArray();
        let matchIdx = uwuify.getRandomInt(0, matches.length);
        let match = matches[matchIdx];

        for (let chrOff = 0; chrOff < match[0].length; chrOff++) {
            let chrIdx = match.index + chrOff;
            let isUpper = text[chrIdx] == text[chrIdx].toUpperCase();
            element.textContent = text.slice(0, chrIdx) + (isUpper ? 'W' : 'w') + text.slice(chrIdx+1);1
        }

        setTimeout(uwuify.uwuify, uwuify.getRandomInt(uwuify.INTERVAL_MIN, uwuify.INTERVAL_MAX));
    }
};



window.addEventListener('load', () => {
    console.debug(`${uwuify.CONSOLE_PREFIX} Document loaded.`);
    let elements = uwuify.getTexts(document.body);
    for (let i = 0; i < elements.length; i++) {
        if (uwuify.isUwuable(elements[i].textContent)) {
            uwuify.TARGET_ELEMENTS.push(elements[i]);
        }
    }
    setTimeout(uwuify.uwuify, uwuify.getRandomInt(uwuify.INTERVAL_MIN, uwuify.INTERVAL_MAX));
});