// ==UserScript==
// @name         telegra.ph enum
// @namespace    https://telegra.ph/
// @version      2025-11-20
// @description  Позволяет одной кнопкой скроллить по датам и страницам на telegra.ph
// @author       anon
// @match        https://telegra.ph/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=2ch.org
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const addButtons = () => {
        const buttonsContainer = document.createElement('div');
        buttonsContainer.style.position = 'fixed';
        buttonsContainer.style.display = 'flex';
        buttonsContainer.style.flexFlow = 'column nowrap';
        buttonsContainer.style.top = '50%';
        buttonsContainer.style.right = '10px';
        buttonsContainer.style.transform = 'translateY(-50%)';
        buttonsContainer.style.zIndex = '1000';
        buttonsContainer.style.backgroundColor = 'white';
        buttonsContainer.style.padding = '10px';
        buttonsContainer.style.borderRadius = '5px';
        buttonsContainer.style.boxShadow = '0 2px 5px rgba(0, 0, 0, 0.5)';

        const createButton = (text, onClick) => {
            const button = document.createElement('button');
            button.innerText = text;
            button.style.margin = '5px';
            button.onclick = onClick;
            buttonsContainer.appendChild(button);
        };

        const changeDate = (dayChange, pageChange) => {
            let currentPath = window.location.pathname.split('/');
            let wordWithDate = currentPath[1]; // Keep the whole string, e.g., "word-02-12[-1]"

            let datePart = wordWithDate.match(/(.*?)-(\d{2})-(\d{2})(?:-(\d+))?/);
            let word = datePart[1]; // Extract the word part
            let month = parseInt(datePart[2]);
            let dayNum = parseInt(datePart[3]) + dayChange;
            // let pageNum = datePart[4] ? parseInt(datePart[4]) + pageChange : 0;
            let pageNum = datePart[4] ? parseInt(datePart[4]) + pageChange : 0;

            // Handle day overflow
            if (dayNum < 1) {
                month -= 1;
                if (month < 1) {
                    month = 12;
                }
                dayNum = 31; // Reset to the last day of the previous month (simplistically)
            }
            if (dayNum > 31) {
                dayNum = 1;
                month += 1;
                if (month > 12) {
                    month = 1;
                }
            }

            const newDate = `${String(month).padStart(2, '0')}-${String(dayNum).padStart(2, '0')}`;
            const newPage = pageNum > 0 ? `-${pageNum}` : pageChange === 1 ? '-1' : '';

            const newPath = `/${word}-${newDate}${newPage}`;
            window.history.pushState({}, '', newPath); // Update URL in the address bar
            window.location.pathname = newPath; // Trigger page load
        };

        createButton('◄', () => changeDate(-1, 0)); // Back by day
        createButton('►', () => changeDate(1, 0));  // Forward by day
        createButton('▲', () => changeDate(0, -1)); // Page up
        createButton('▼', () => changeDate(0, 1));  // Page down

        document.body.appendChild(buttonsContainer);
    };

    addButtons();
})();