/* line numbers */
updateLineNumber(location.hash);

for (let line of document.querySelectorAll('.line-number')) {
    line.addEventListener("click", () =>
        updateLineNumber(line.attributes.getNamedItem("id").value));
}

function updateLineNumber(id) {
    if (id && id.startsWith('#')) {
        id = id.substring(1);
    }

    if (!id) {
        return;
    }

    let element = document.getElementById(id);
    if (element.classList.contains("line-number")) {
        for (const line of document.querySelectorAll(".line-active")) {
            line.classList.remove("line-active");
        }
        element.closest('.entry').classList.add('line-active');
    }
}

/* Scroll to top/bottom buttons */
const downButton = document.getElementById("down-button");
if (downButton) {
    downButton.addEventListener("click", () => scrollToHeight(document.body.scrollHeight));
}

const upButton = document.getElementById("up-button");
if (upButton) {
    upButton.addEventListener("click", () => scrollToHeight(0));
}

/**
 * Scroll to a specific height
 * Disable smooth scrolling for large pages
 * @param {number} top height to scroll to
 * @param {number} [smoothScrollLimit] only use smooth scrolling if the distance is less than this value
 */
function scrollToHeight(top, smoothScrollLimit = 10000) {
    const distance = Math.abs(document.documentElement.scrollTop - top);
    const behavior = (distance < smoothScrollLimit) ? "smooth" : "instant";
    window.scrollTo({left: 0, top, behavior});
}

/*
 * Error collapse toggle.
 *
 * Smart fold: every entry within ±ERROR_WINDOW_SIZE of an error stays
 * visible; runs of non-error entries with no nearby errors collapse into
 * a draggable fold bar. Vertical drag on the bar progressively reveals or
 * re-hides lines; a click without drag reveals the next DEFAULT_CLICK_REVEAL
 * lines.
 */
const ERROR_WINDOW_SIZE = 25;
const PIXELS_PER_LINE_DRAG = 6;
const DEFAULT_CLICK_REVEAL = 25;
const DRAG_PIXEL_THRESHOLD = 3;

const toggleErrorsButton = document.getElementById("error-toggle");
if (toggleErrorsButton) {
    toggleErrorsButton.addEventListener("click", toggleErrors);
}

function toggleErrors() {
    if (toggleErrorsButton.classList.contains("toggled")) {
        toggleErrorsButton.classList.remove("toggled");
        uncollapseAllErrors();
    } else {
        toggleErrorsButton.classList.add("toggled");
        collapseAllErrors();
    }
}

function collapseAllErrors() {
    const lines = Array.from(document.querySelectorAll('.log-inner > .entry'));
    const total = lines.length;
    if (!total) return;

    // Pass 1: mark entries within ±ERROR_WINDOW_SIZE of any error.
    const mustShow = new Array(total).fill(false);
    for (let i = 0; i < total; i++) {
        if (lines[i].classList.contains("entry-error")) {
            const lo = Math.max(0, i - ERROR_WINDOW_SIZE);
            const hi = Math.min(total - 1, i + ERROR_WINDOW_SIZE);
            for (let j = lo; j <= hi; j++) mustShow[j] = true;
        }
    }

    // Pass 2: hide unmarked entries; emit a fold bar at the START of each run.
    let runEntries = [];
    const flushRun = () => {
        if (!runEntries.length) return;
        const bar = createFoldBar(runEntries);
        runEntries[0].insertAdjacentElement("beforebegin", bar);
        runEntries = [];
    };
    for (let i = 0; i < total; i++) {
        if (!mustShow[i]) {
            lines[i].style.display = "none";
            runEntries.push(lines[i]);
        } else {
            flushRun();
        }
    }
    flushRun();
}

function uncollapseAllErrors() {
    document.querySelectorAll(".log-inner > .entry").forEach(line => line.style.removeProperty("display"));
    document.querySelectorAll(".collapsed-lines").forEach(bar => bar.remove());
}

function createFoldBar(entries) {
    const bar = document.createElement("div");
    bar.classList.add("collapsed-lines", "collapsed-lines-foldable");
    bar.appendChild(document.createElement("div")); // line-number column slot

    const count = document.createElement("div");
    count.classList.add("collapsed-lines-count");
    bar.appendChild(count);

    bar._hiddenEntries = entries;
    bar._revealedCount = 0;
    renderFoldLabel(bar);
    attachFoldDragHandler(bar);
    return bar;
}

function renderFoldLabel(bar) {
    const entries = bar._hiddenEntries;
    const total = entries.length;
    const revealed = bar._revealedCount;
    const remaining = total - revealed;
    const count = bar.querySelector(".collapsed-lines-count");
    count.replaceChildren();

    if (remaining <= 0) return;

    const firstHiddenLine = parseInt(entries[revealed].querySelector(".line-number").innerHTML, 10);
    const lastHiddenLine = parseInt(entries[total - 1].querySelector(".line-number").innerHTML, 10);
    const word = remaining === 1 ? "line" : "lines";

    const grip = document.createElement("i");
    grip.className = "fa-solid fa-grip-lines";
    count.appendChild(grip);
    count.append(` ${remaining} ${word} hidden · ${firstHiddenLine}–${lastHiddenLine} · drag to reveal `);
    count.appendChild(grip.cloneNode());
}

function applyFoldReveal(bar, n) {
    const entries = bar._hiddenEntries;
    n = Math.max(0, Math.min(entries.length, n));
    if (n === bar._revealedCount) return;
    for (let i = 0; i < entries.length; i++) {
        if (i < n) entries[i].style.removeProperty("display");
        else entries[i].style.display = "none";
    }
    bar._revealedCount = n;
    renderFoldLabel(bar);
}

function attachFoldDragHandler(bar) {
    let dragging = false;
    let dragStartY = 0;
    let dragStartReveal = 0;
    let didDrag = false;

    bar.addEventListener("pointerdown", (e) => {
        if (e.button !== 0) return;
        dragging = true;
        didDrag = false;
        dragStartY = e.clientY;
        dragStartReveal = bar._revealedCount;
        bar.setPointerCapture(e.pointerId);
        bar.classList.add("collapsed-lines-dragging");
        e.preventDefault();
    });

    bar.addEventListener("pointermove", (e) => {
        if (!dragging) return;
        const dy = e.clientY - dragStartY;
        if (Math.abs(dy) >= DRAG_PIXEL_THRESHOLD) didDrag = true;
        const target = dragStartReveal + Math.round(dy / PIXELS_PER_LINE_DRAG);
        applyFoldReveal(bar, target);
    });

    const finish = (e) => {
        if (!dragging) return;
        dragging = false;
        try { bar.releasePointerCapture(e.pointerId); } catch {}
        bar.classList.remove("collapsed-lines-dragging");

        if (!didDrag) {
            // Plain click: reveal the next chunk of lines.
            applyFoldReveal(bar, bar._revealedCount + DEFAULT_CLICK_REVEAL);
        }
        if (bar._revealedCount >= bar._hiddenEntries.length) {
            bar.remove();
        }
    };
    bar.addEventListener("pointerup", finish);
    bar.addEventListener("pointercancel", finish);
}

/* convert timestamps */
let timeElements = document.querySelectorAll('[data-time]');
for (const element of timeElements) {
    const timestamp = parseInt(element.dataset.time);
    if (isNaN(timestamp)) {
        continue;
    }
    const date = new Date(timestamp * 1000);
    element.innerHTML = date.toLocaleString();
}

/* settings */
const settingCheckboxes = document.querySelectorAll(".setting-checkbox");
settingCheckboxes.forEach(checkbox => checkbox.addEventListener("change", handleSettingChange));

let settingsChannel = null;
if (typeof BroadcastChannel !== "undefined") {
    settingsChannel = new BroadcastChannel("mc-logs-settings");
    settingsChannel.onmessage = (e) => {
        if (e.data.type === "settings-updated") {
            for (const checkbox of settingCheckboxes) {
                checkbox.checked = !!e.data.settings[checkbox.dataset.key];
                applySetting(checkbox);
            }
        }
    };
}

function handleSettingChange(e) {
    let checkbox = e.target;
    applySetting(checkbox);
    saveSettings();
    if (settingsChannel) {
        settingsChannel.postMessage({
            type: "settings-updated",
            settings: getCurrentSettings()
        });
    }
}

function applySetting(checkbox) {
    let bodyClass = checkbox.dataset.bodyClass;
    if (checkbox.checked) {
        document.body.classList.add(bodyClass);
    } else {
        document.body.classList.remove(bodyClass);
    }
    switch (checkbox.dataset.key) {
        case "floatingScrollbar":
            initFloatingScrollbar();
            break;
    }
}

function getCurrentSettings() {
    const data = {};
    for (const checkbox of settingCheckboxes) {
        data[checkbox.dataset.key] = checkbox.checked;
    }
    return data;
}

function saveSettings() {
    const data = {};
    for (const checkbox of settingCheckboxes) {
        data[checkbox.dataset.key] = checkbox.checked;
    }
    document.cookie = "IBLOGS_SETTINGS=" + encodeURIComponent(JSON.stringify(data)) + ";path=/;expires=" + new Date(new Date().getTime() + 100 * 365 * 24 * 60 * 60 * 1000).toUTCString();
}

/* copy to clipboard */
const copyButtons = document.querySelectorAll("[data-clipboard]");
copyButtons.forEach(button => button.addEventListener("click", handleCopyButtonClick));
const doneClassName = "fa-solid fa-check";

async function handleCopyButtonClick(e) {
    const button = e.currentTarget;
    const data = button.dataset.clipboard;
    await navigator.clipboard.writeText(data);

    const iconElement = button.querySelector("i");
    if (!iconElement) {
        return;
    }
    const originalClassName = iconElement.className;
    if (originalClassName === doneClassName) {
        return;
    }
    iconElement.className = doneClassName;
    setTimeout(() => {
        iconElement.className = originalClassName;
    }, 2000);
}

/* delete button */
const deleteButton = document.querySelector(".delete-log-button");
const deleteErrorElement = document.querySelector(".delete-overlay .popover-error");
if (deleteButton) {
    deleteButton.addEventListener("click", handleDeleteButtonClick);
}

async function handleDeleteButtonClick() {
    deleteErrorElement.style.display = "none";
    const response = await fetch(window.location.href, {
        method: "DELETE",
        credentials: "include"
    });
    if (!response.ok) {
        deleteErrorElement.style.display = "block";
        deleteErrorElement.textContent = `${response.status} (${response.statusText})`;
        return;
    }
    window.location.href = "/";
}

/* floating scroll bar */
const browser = getComputedStyle(document.body)
    .getPropertyValue("--browser")
    .replaceAll(/['"]/g, '')
    .trim()
    .toLowerCase();
const floatingScrollbar = document.querySelector(".floating-scrollbar");
let logContainer = null;
if (browser === "firefox") {
    logContainer = document.querySelector(".log");
} else {
    logContainer = document.querySelector(".log-inner");
}

if (floatingScrollbar && logContainer) {
    updateFloatingScrollbarWidths();

    floatingScrollbar.addEventListener("scroll", () => {
        syncScroll(floatingScrollbar, logContainer);
    });

    logContainer.addEventListener("scroll", () => {
        syncScroll(logContainer, floatingScrollbar);
    });

    const observer = new ResizeObserver(() => {
        updateFloatingScrollbarWidths();
    });
    observer.observe(logContainer);
}

function syncScroll(source, target) {
    if (Math.abs(source.scrollLeft - target.scrollLeft) > 1) {
        target.scrollLeft = source.scrollLeft;
    }
}

function initFloatingScrollbar() {
    if (!floatingScrollbar || !logContainer) {
        return;
    }
    updateFloatingScrollbarWidths();
    syncScroll(logContainer, floatingScrollbar);
}

function updateFloatingScrollbarWidths() {
    floatingScrollbar.style.setProperty(
        "--floating-scrollbar-width",
        `${logContainer.clientWidth}px`
    );

    floatingScrollbar.style.setProperty(
        "--floating-scrollbar-content-width",
        `${logContainer.scrollWidth}px`
    );
}