let configHistoryEntries = [], configHistorySelectedRevision = null, configHistorySelectedJson = null;
function historyDate(value, options = {}) {
    const effective = { ...options };
    if (Object.hasOwn(effective, "timeStyle") || Object.hasOwn(effective, "hour")) effective.hour12 = (adminPreferences?.time_format || "24h") === "12h";
    try { return new Intl.DateTimeFormat(locale(), effective).format(new Date(Number(value) * 1000)); }
    catch { return formatDateTime(Number(value) * 1000); }
}
function historyDayKey(value) {
    const date = new Date(Number(value) * 1000);
    return `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, "0")}-${String(date.getDate()).padStart(2, "0")}`;
}
function historyMonthKey(value) { return historyDayKey(value).slice(0, 7); }
function historyValue(value) {
    if (value === undefined) return t("configHistoryMissing");
    const result = JSON.stringify(value);
    return result.length > 320 ? `${result.slice(0, 320)}…` : result;
}
function syncConfigHistoryRestoreButton() {
    const button = $("config-history-restore"), revision = Number(configHistorySelectedRevision);
    if (!button) return;
    button.hidden = configHistorySelectedRevision === null;
    button.disabled = busy || !envelope || !Number.isSafeInteger(revision) || revision >= Number(envelope.revision);
}
// Compare leaf fields, not serialized object/array blobs. Object IDs are used
// for stable array paths so reordering vhosts does not become a huge fake diff.
function configDiff(before, after, path = "$", output = [], depth = 0) {
    if (output.length >= 200 || Object.is(before, after)) return output;
    if (depth >= 24) {
        if (JSON.stringify(before) !== JSON.stringify(after)) output.push({ path, before: "[nested value]", after: "[nested value]" });
        return output;
    }
    const oldObj = before !== null && typeof before === "object";
    const newObj = after !== null && typeof after === "object";
    if (oldObj && newObj && !Array.isArray(before) && !Array.isArray(after)) {
        const keys = [...new Set([...Object.keys(before), ...Object.keys(after)])].sort();
        for (const key of keys) {
            if (output.length >= 200) break;
            configDiff(before[key], after[key], `${path}[${JSON.stringify(key)}]`, output, depth + 1);
        }
        return output;
    }
    if (Array.isArray(before) && Array.isArray(after)) {
        const named = items => items.every(item => item && typeof item === "object" && !Array.isArray(item) && (typeof item.id === "string" || typeof item.name === "string"));
        const itemKey = item => String(item.id ?? item.name);
        const stable = named(before) && named(after)
            && new Set(before.map(itemKey)).size === before.length
            && new Set(after.map(itemKey)).size === after.length;
        if (stable) {
            const oldItems = new Map(before.map(item => [itemKey(item), item]));
            const newItems = new Map(after.map(item => [itemKey(item), item]));
            for (const id of new Set([...oldItems.keys(), ...newItems.keys()])) {
                if (output.length >= 200) break;
                configDiff(oldItems.get(id), newItems.get(id), `${path}[${JSON.stringify(id)}]`, output, depth + 1);
            }
        } else {
            for (let i = 0; i < Math.max(before.length, after.length) && output.length < 200; i++) {
                configDiff(before[i], after[i], `${path}[${i}]`, output, depth + 1);
            }
        }
        return output;
    }
    // New/deleted trees are traversed to show the affected fields only.
    const tree = oldObj ? before : newObj ? after : null;
    if (tree && !Array.isArray(tree)) {
        for (const key of Object.keys(tree).sort()) {
            if (output.length >= 200) break;
            configDiff(before?.[key], after?.[key], `${path}[${JSON.stringify(key)}]`, output, depth + 1);
        }
        return output;
    }
    if (Array.isArray(tree)) {
        for (let i = 0; i < tree.length && output.length < 200; i++) {
            configDiff(before?.[i], after?.[i], `${path}[${i}]`, output, depth + 1);
        }
        return output;
    }
    if (JSON.stringify(before) !== JSON.stringify(after)) output.push({ path, before, after });
    return output;
}
function renderConfigRevisionDetail(detail) {
    const entry = detail?.revision;
    if (!entry) return;
    configHistorySelectedRevision = Number(entry.revision);
    configHistorySelectedJson = entry.previous_config ? { before: entry.previous_config, after: entry.config } : null;
    const compareButton = $("config-history-compare-open");
    compareButton.disabled = !configHistorySelectedJson;
    $("config-history-detail-title").textContent = `${t("configHistoryRevision")} ${entry.revision}`;
    $("config-history-detail-meta").textContent = `${historyDate(entry.time, { dateStyle: "medium", timeStyle: "short" })} · ${entry.actor}`;
    syncConfigHistoryRestoreButton();
    document.querySelectorAll(".config-history-revision").forEach(button => button.classList.toggle("active", Number(button.dataset.revision) === Number(entry.revision)));
    const box = $("config-history-diff"); box.replaceChildren();
    if (!entry.previous_config) { box.append(el("p", t("configHistoryBaseline"), "empty")); return; }
    const diff = configDiff(entry.previous_config, entry.config);
    if (!diff.length) { box.append(el("p", t("configHistoryNoChanges"), "empty")); return; }
    for (const change of diff) {
        const card = el("article", undefined, "config-history-change");
        card.append(el("strong", change.path, "config-history-change-path"));
        const values = el("div", undefined, "config-history-change-values");
        values.append(el("code", historyValue(change.before), "diff-before"), el("span", "→", "fine"), el("code", historyValue(change.after), "diff-after"));
        card.append(values); box.append(card);
    }
    if (diff.length >= 200) box.append(el("p", t("configHistoryDiffLimit"), "fine"));
}
async function loadConfigRevision(revision) {
    try { renderConfigRevisionDetail(await api(`/api/config/history?revision=${encodeURIComponent(revision)}`)); }
    catch (error) { toast(error.message, true); }
}
function selectConfigHistoryDay(dayKey, entries) {
    document.querySelectorAll(".config-history-day").forEach(button => button.classList.toggle("is-selected", button.dataset.day === dayKey));
    const revisions = $("config-history-revisions"); revisions.replaceChildren();
    const sorted = [...entries].sort((a, b) => b.revision - a.revision);
    for (const entry of sorted) {
        const button = el("button", `${t("configHistoryRevisionShort")} ${entry.revision}`, "quiet config-history-revision");
        button.type = "button"; button.dataset.revision = entry.revision; button.title = `${entry.actor} · ${historyDate(entry.time, { dateStyle: "medium", timeStyle: "short" })}`;
        button.addEventListener("click", () => void loadConfigRevision(entry.revision)); revisions.append(button);
    }
    if (sorted[0]) void loadConfigRevision(sorted[0].revision);
}
function renderConfigHistory() {
    const calendar = $("config-history-calendar"); calendar.replaceChildren();
    const byMonth = new Map(), byDay = new Map();
    for (const entry of configHistoryEntries) {
        const month = historyMonthKey(entry.time), day = historyDayKey(entry.time);
        if (!byMonth.has(month)) byMonth.set(month, []); byMonth.get(month).push(entry);
        if (!byDay.has(day)) byDay.set(day, []); byDay.get(day).push(entry);
    }
    $("config-history-summary").textContent = configHistoryEntries.length ? t("configHistorySummary").replace("{count}", configHistoryEntries.length) : t("configHistoryEmpty");
    const months = [...byMonth.keys()].sort().reverse();
    for (const key of months) {
        const [yearText, monthText] = key.split("-"), year = Number(yearText), month = Number(monthText) - 1;
        const panel = el("section", undefined, "config-history-month");
        panel.append(el("h4", new Intl.DateTimeFormat(locale(), { month: "long", year: "numeric" }).format(new Date(year, month, 1))));
        const weekdays = el("div", undefined, "config-history-weekdays");
        for (let day = 0; day < 7; day++) weekdays.append(el("span", new Intl.DateTimeFormat(locale(), { weekday: "narrow" }).format(new Date(2024, 0, 7 + day))));
        panel.append(weekdays);
        const days = el("div", undefined, "config-history-days"), first = new Date(year, month, 1).getDay(), count = new Date(year, month + 1, 0).getDate();
        for (let blank = 0; blank < first; blank++) days.append(el("span", "", "config-history-day"));
        for (let day = 1; day <= count; day++) {
            const dayKey = `${yearText}-${monthText}-${String(day).padStart(2, "0")}`, entries = byDay.get(dayKey) || [];
            const node = el(entries.length ? "button" : "span", String(day), `config-history-day${entries.length ? " has-revisions" : ""}`);
            if (entries.length) {
                node.type = "button"; node.dataset.day = dayKey;
                node.append(el("small", `${entries.length} ${t("configHistoryEntries")}`, "config-history-day-count"));
                node.addEventListener("click", () => selectConfigHistoryDay(dayKey, entries));
            }
            days.append(node);
        }
        panel.append(days); calendar.append(panel);
    }
    if (!months.length) calendar.append(el("p", t("configHistoryEmpty"), "empty"));
}
async function restoreConfigRevision() {
    const revision = Number(configHistorySelectedRevision);
    if (!envelope || busy || !Number.isSafeInteger(revision) || revision >= Number(envelope.revision)) return;
    const expectedRevision = Number(envelope.revision);
    const message = t("configHistoryRestoreConfirm").replace("{revision}", revision).replace("{current}", expectedRevision);
    if (!(await appConfirm(message, { danger: true, confirmLabel: t("configHistoryRestoreAction") }))) return;
    const button = $("config-history-restore"), epoch = authEpoch;
    busy = true; syncConfigHistoryRestoreButton();
    try {
        const value = await api("/api/config/history/restore", { method: "POST", body: JSON.stringify({ revision, expected_revision: expectedRevision }) });
        if (!authenticated || epoch !== authEpoch) return;
        envelope = value;
        await refreshCertificateInventory();
        if (!authenticated || epoch !== authEpoch) return;
        renderConfig();
        toast(t("configHistoryRestored").replace("{revision}", revision).replace("{new_revision}", value.revision));
        await refresh(true);
        if (authenticated && epoch === authEpoch) await loadConfigHistory();
    } catch (error) { toast(error.message, true); if (error.status === 401) lock(); }
    finally { busy = false; if (button?.isConnected) syncConfigHistoryRestoreButton(); }
}
async function loadConfigHistory() {
    configHistorySelectedRevision = null; configHistorySelectedJson = null; $("config-history-compare-open").disabled = true; syncConfigHistoryRestoreButton();
    $("config-history-summary").textContent = t("configHistoryLoading");
    try {
        const result = await api("/api/config/history?limit=512"); configHistoryEntries = result.revisions || []; renderConfigHistory();
        const latest = configHistoryEntries[0]; if (latest) selectConfigHistoryDay(historyDayKey(latest.time), configHistoryEntries.filter(entry => historyDayKey(entry.time) === historyDayKey(latest.time)));
    } catch (error) { $("config-history-summary").textContent = t("configHistoryFailed"); toast(error.message, true); }
}
$("config-history-open").addEventListener("click", () => { const dialog = $("config-history-dialog"); if (!dialog.open) dialog.showModal(); void loadConfigHistory(); });
$("config-history-close").addEventListener("click", () => $("config-history-dialog").close());
$("config-history-reload").addEventListener("click", () => void loadConfigHistory());
$("config-history-restore").addEventListener("click", () => void restoreConfigRevision());

$("config-history-compare-open").addEventListener("click", () => {
    if (!configHistorySelectedJson) return;
    $("config-history-json-before").textContent = JSON.stringify(configHistorySelectedJson.before, null, 2);
    $("config-history-json-after").textContent = JSON.stringify(configHistorySelectedJson.after, null, 2);
    const dialog = $("config-history-json-dialog"); if (!dialog.open) dialog.showModal();
});
$("config-history-json-close").addEventListener("click", () => $("config-history-json-dialog").close());