function isOneTimeDownloadSelected() {
    return el.expiry?.value === oneTimeRetentionKey;
}

function syncZipForRetention() {
    if (!el.allowZip) return;
    if (isOneTimeDownloadSelected()) {
        el.allowZip.checked = true;
        el.allowZip.disabled = true;
    } else if (!uploadLocked) {
        el.allowZip.disabled = false;
    }
}

function setBoxOptionsLocked(locked) {
    const controls = [el.expiry, el.password, el.maxViews, el.boxName, el.customSlug, el.downloadPage, el.allowZip, el.allowPreview, el.keepFilenames, el.privateBox, el.apiKeyMode, el.apiKeyInput].filter(Boolean);
    el.optionsForm?.classList.toggle("is-locked", locked);
    controls.forEach((control) => {
        control.dataset.disabledReason = locked ? "Box Options are locked because this box was already created. Press Clear to start another upload." : "";
        if (control.tagName === "INPUT" && !["checkbox", "radio", "file"].includes(control.type)) {
            control.readOnly = locked;
        } else {
            control.disabled = locked;
        }
    });
    if (el.password) el.password.type = locked ? "password" : "text";
    if (!locked) {
        syncZipForRetention();
        syncApiKeyField();
    }
    updateDisabledReasons();
}

function updateDisabledReasons() {
    if (el.startButton) {
        let reason = "";
        const policyMessage = apiKeyPolicyMessage();
        if (!uploadsEnabled) reason = "Guest uploads are disabled.";
        else if (uploadLocked) reason = "This upload already started. Press Clear to create another box.";
        else if (policyMessage) reason = policyMessage;
        else if (hasQuotaError()) reason = "Over maximum upload size. Remove highlighted files or clear some files.";
        else if (!files.length) reason = "There are no files selected. Please select files to upload.";
        el.startButton.disabled = false;
        el.startButton.setAttribute("aria-disabled", reason ? "true" : "false");
        el.startButton.dataset.disabledReason = reason;
        el.startButton.title = reason;
    }
    if (el.fileInput) {
        el.fileInput.dataset.disabledReason = uploadLocked ? "The current box is sealed after upload. Press Clear to start a new box." : (!uploadsEnabled ? "Guest uploads are disabled." : "");
    }
    if (el.dropzone) {
        el.dropzone.dataset.disabledReason = uploadLocked ? "The current box is sealed after upload. Press Clear to start a new box." : (!uploadsEnabled ? "Guest uploads are disabled." : "");
    }
    document.querySelectorAll('[data-action="start-upload"]').forEach((button) => {
        const reason = el.startButton?.dataset.disabledReason || "";
        button.setAttribute("aria-disabled", reason ? "true" : "false");
        button.dataset.disabledReason = reason;
    });
    document.querySelectorAll('[data-action="browse"]').forEach((button) => {
        const reason = uploadLocked ? "The current box is sealed after upload. Press Clear to start a new box." : (!uploadsEnabled ? "Guest uploads are disabled." : "");
        button.setAttribute("aria-disabled", reason ? "true" : "false");
        button.dataset.disabledReason = reason;
    });
    document.querySelectorAll('[data-action="copy-link"]').forEach((button) => {
        button.setAttribute("aria-disabled", shareUrl ? "false" : "true");
        button.dataset.disabledReason = shareUrl ? "" : "There is no share URL yet. Start an upload first.";
    });
}

function saveSettings() {
    const apiKey = el.apiKeyMode?.checked && validApiKey(el.apiKeyInput?.value || "") ? el.apiKeyInput.value.trim() : "";
    const settings = {
        maxViews: el.maxViews?.value || "",
        allowPreview: Boolean(el.allowPreview?.checked),
        keepFilenames: Boolean(el.keepFilenames?.checked),
        privateBox: Boolean(el.privateBox?.checked),
        apiKeyMode: Boolean(el.apiKeyMode?.checked),
        apiKey,
    };
    localStorage.setItem(SETTINGS_KEY, JSON.stringify(settings));
}

function loadSettings() {
    let settings = {};
    try {
        settings = JSON.parse(localStorage.getItem(SETTINGS_KEY) || "{}");
    } catch (_) {}
    if (el.maxViews) el.maxViews.value = settings.maxViews || "";
    if (el.allowPreview) el.allowPreview.checked = settings.allowPreview !== false;
    if (el.keepFilenames) el.keepFilenames.checked = settings.keepFilenames !== false;
    if (el.privateBox) el.privateBox.checked = Boolean(settings.privateBox);
    if (el.apiKeyMode) el.apiKeyMode.checked = Boolean(settings.apiKeyMode);
    if (el.apiKeyInput) el.apiKeyInput.value = validApiKey(settings.apiKey || "") ? settings.apiKey : "";
    syncZipForRetention();
    syncApiKeyField();
    saveSettings();
}

function syncMenuChecks() {
    updateDisabledReasons();
}

function syncApiKeyField() {
    const enabled = Boolean(el.apiKeyMode?.checked) && !uploadLocked;
    el.apiKeyRow?.classList.toggle("is-visible", Boolean(el.apiKeyMode?.checked));
    if (!el.apiKeyMode?.checked) {
        clearTimeout(apiKeyTimer);
        apiKeyValidationRun += 1;
        resetAccountLimits();
        updateLimitHint();
        renderFiles();
    }
    if (el.apiKeyInput) {
        el.apiKeyInput.disabled = !enabled;
        el.apiKeyInput.dataset.disabledReason = enabled ? "" : "Enable Use API key for larger quota before typing an API key.";
    }
    validateApiKeyField();
}

function validateApiKeyField() {
    if (!el.apiKeyInput || !el.apiKeyState) return;
    clearTimeout(apiKeyTimer);
    const wrapper = el.apiKeyInput.closest(".api-key-field");
    wrapper?.classList.remove("is-checking");

    if (!el.apiKeyMode?.checked) {
        apiKeyValidationRun += 1;
        resetAccountLimits();
        el.apiKeyState.textContent = "";
        updateLimitHint();
        renderFiles();
        return;
    }
    const value = el.apiKeyInput.value.trim();
    if (!value) {
        apiKeyValidationRun += 1;
        resetAccountLimits();
        el.apiKeyState.textContent = "waiting";
        updateLimitHint();
        renderFiles();
        saveSettings();
        return;
    }

    if (!validApiKey(value)) {
        apiKeyValidationRun += 1;
        resetAccountLimits();
        el.apiKeyInput.value = "";
        el.apiKeyState.textContent = "invalid";
        updateLimitHint();
        renderFiles();
        saveSettings();
        showToast("Invalid API key removed. Paste a valid API key to save it.", "warning");
        return;
    }

    const runID = apiKeyValidationRun + 1;
    apiKeyValidationRun = runID;
    el.apiKeyInput.disabled = true;
    wrapper?.classList.add("is-checking");
    el.apiKeyState.textContent = "checking";
    apiKeyTimer = setTimeout(async () => {
        try {
            const response = await fetch("/auth/me", {
                headers: { Authorization: `Bearer ${value}` },
            });
            let payload = {};
            try {
                payload = await response.json();
            } catch (_) {}
            if (runID !== apiKeyValidationRun) return;
            wrapper?.classList.remove("is-checking");
            el.apiKeyInput.disabled = uploadLocked;
            if (!response.ok || !payload.user) {
                resetAccountLimits();
                el.apiKeyInput.value = "";
                el.apiKeyState.textContent = "invalid";
                updateLimitHint();
                renderFiles();
                saveSettings();
                showToast(payload.error || "API key was not accepted.", "warning");
                return;
            }

            applyAccountLimits(payload.user);
            const policyMessage = apiKeyPolicyMessage();
            const fileText = maxFileBytes ? formatBytes(maxFileBytes) : "unlimited";
            const boxText = maxBoxBytes ? formatBytes(maxBoxBytes) : "unlimited";
            el.apiKeyState.textContent = policyMessage ? "limited by policy" : "account limits applied";
            updateLimitHint();
            renderFiles();
            saveSettings();
            setStatus(`${payload.user.username || payload.user.email} limits: file ${fileText}, box ${boxText}`);
            if (policyMessage) showToast(policyMessage, "warning");
        } catch (_) {
            if (runID !== apiKeyValidationRun) return;
            wrapper?.classList.remove("is-checking");
            el.apiKeyInput.disabled = uploadLocked;
            resetAccountLimits();
            updateLimitHint();
            renderFiles();
            el.apiKeyState.textContent = "check failed";
            showToast("Could not check API key limits.", "warning");
        }
    }, 650);
}

function validApiKey(value) {
    return /^[A-Za-z0-9._-]{12,}$/.test(String(value || "").trim());
}

function slugify(value) {
    return String(value || "")
        .toLowerCase()
        .replace(/[^a-z0-9-]+/g, "-")
        .replace(/-+/g, "-")
        .replace(/^-|-$/g, "")
        .slice(0, 32);
}

function sanitizeSlugInput(value) {
    return String(value || "")
        .toLowerCase()
        .replace(/[^a-z0-9-]/g, "")
        .replace(/-+/g, "-")
        .slice(0, 32);
}

function syncSlugFromName(force = false) {
    if (!el.customSlug || !el.boxName) return;
    if (force || !el.customSlug.value || el.customSlug.dataset.auto === "true") {
        el.customSlug.value = slugify(el.boxName.value);
        el.customSlug.dataset.auto = "true";
    }
    saveSettings();
    updateTerminal();
}

function randomPassword() {
    if (!el.password || uploadLocked) return;
    el.password.value = `${Math.random().toString(36).slice(2, 8)}-${Math.random().toString(36).slice(2, 6)}`;
    saveSettings();
    updateTerminal();
    setStatus("Generated a password");
}

function randomBoxName() {
    if (!el.boxName || uploadLocked) return;
    const adjectives = ["Neon", "Turbo", "Quiet", "Cosmic", "Lucky", "Midnight", "Pixel", "Rapid"];
    const nouns = ["Floppy Disk", "Archive Box", "Packet Portal", "Upload Folder", "Cache Drive", "Release Bundle"];
    el.boxName.value = `${adjectives[Math.floor(Math.random() * adjectives.length)]} ${nouns[Math.floor(Math.random() * nouns.length)]}`;
    syncSlugFromName(true);
    setStatus("Generated a local box name");
}