const xEventMap = {
  AddToCart:   'tw-pn6ci-pn6cm',
  ViewPricePlan:       'tw-pn6ci-przrx',
  Purchase:  'tw-pn6ci-pn6cj',
  Answered5CorrectQuestions:  'tw-pn6ci-przsx',
  Answered20CorrectQuestions:  'tw-pn6ci-przsy',
  Answered50CorrectQuestions:  'tw-pn6ci-przsz',
  StartTrial:  'tw-pn6ci-przso',
  NoG1:  'tw-pn6ci-prztp'
};

/* === 生成唯一 event_id === */
function generateEventId() {
    return 'ev-' + Date.now() + '-' + Math.random().toString(36).substr(2, 9);
}

/* === 轻量封装：像 sendCapiEvent 一样，同时返回 event_id === */
function capiAndPixelTrack(eventName, pixelPayload = {}, capiPayload = {}) {
    const eid = generateEventId();                // ① 生成
    // ② Pixel 侧：带上 eventID
    fbq('track', eventName, pixelPayload, { eventID: eid });
    // for x
    if (typeof twq === 'function') {
        // ① 根据 fb eventName 找到 X 的事件标识
        const xEventId = xEventMap[eventName] || eventName;
        // ② 用 'event' 方法触发，并带上 conversion_id
        twq('event', xEventId, {
            ...pixelPayload,
            conversion_id: eid
        });
    }

    // ③ CAPI 侧：带上 event_id
    sendCapiEvent(eventName, { ...capiPayload, event_id: eid });
}

// 从 Cookie 里提取完整的 fb.1.xxx fbc
function getFbcFromCookie() {
    const match = document.cookie.match(/(?:^|; )_fbc=(fb\.1\.\d+\.[^;]+)/);
    return match ? decodeURIComponent(match[1]) : null;
}

function sendCapiEvent(eventName, options = {}) {
    const email = options.email || localStorage.getItem('userEmail'); // 可选
    const body = {
        event_name: eventName,
        event_source_url: options.event_source_url || window.location.href
    };

    if (options.event_id) body.event_id = options.event_id;

    if (email) {
        body.email = email;
    }

    // ⇒ 从 Cookie 里拿完整的 fbc
    const fbc = getFbcFromCookie();
    if (fbc) {
        body.fbc = fbc;
    }

    // ⇒ 同理可加 fbp（浏览器 ID）
    const fbpMatch = document.cookie.match(/(?:^|; )_fbp=(fb\.1\.\d+\.[^;]+)/);
    if (fbpMatch) {
        body.fbp = decodeURIComponent(fbpMatch[1]);
    }

    if (options.value) {
        body.value = options.value;
    }
    if (options.currency) {
        body.currency = options.currency;
    }

    fetch('capi-track.php', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body)
    }).then(res => {
        if (!res.ok) console.warn('CAPI event failed:', eventName);
    });
}