Update click ID tracking

click-id-tracking.js

@@ -1,38 +1,27 @@
-// Persist Google Ads click identifiers (gclid / wbraid / gbraid) from the
-// landing URL into cookies scoped to photon.codes, so conversions can be
-// attributed after the visitor navigates within the site.
-//
-// Mintlify auto-includes any `.js` file in the content directory on every
-// page and runs it once the page is interactive. That captures the initial
-// landing URL, which is all click-ID attribution needs.
-//
-// A single identifier is stored (Google normally provides one). A genuinely
-// new click replaces prior attribution and resets the capture timestamp,
-// while a reload of the same click preserves the original 90-day window.
-
 (() => {
   const CLICK_ID_KEYS = ['gclid', 'wbraid', 'gbraid']
-  const CLICK_COOKIE_PREFIX = 'photon_'
-  const CAPTURED_AT_COOKIE_NAME = 'photon_ads_click_captured_at'
+  const COOKIE_PREFIX = 'photon_'
+  const CAPTURED_AT_COOKIE = 'photon_ads_click_captured_at'
   const COOKIE_DOMAIN = 'photon.codes'
-  const COOKIE_MAX_AGE = 90 * 24 * 60 * 60
+  const COOKIE_MAX_AGE_SECONDS = 90 * 24 * 60 * 60
   const MAX_CLICK_ID_LENGTH = 512
-  const COOKIE_ATTRIBUTES
+
+  const cookieAttributes
     = `Domain=${COOKIE_DOMAIN}; Path=/; SameSite=Lax; Secure`
 
   const readCookie = (name) => {
     const prefix = `${name}=`
-    const pair = document.cookie
+    const cookie = document.cookie
       .split(';')
       .map(item => item.trim())
       .find(item => item.startsWith(prefix))
 
-    if (!pair) {
+    if (!cookie) {
       return null
     }
 
     try {
-      return decodeURIComponent(pair.slice(prefix.length))
+      return decodeURIComponent(cookie.slice(prefix.length))
     }
     catch {
       return null
@@ -42,72 +31,64 @@
   const writeCookie = (name, value) => {
     document.cookie
       = `${name}=${encodeURIComponent(value)}; `
-        + `Max-Age=${COOKIE_MAX_AGE}; ${
-          COOKIE_ATTRIBUTES}`
+        + `Max-Age=${COOKIE_MAX_AGE_SECONDS}; ${
+          cookieAttributes}`
   }
 
   const deleteCookie = (name) => {
     document.cookie
-      = `${name}=; Max-Age=0; ${
-        COOKIE_ATTRIBUTES}`
+      = `${name}=; Max-Age=0; ${cookieAttributes}`
   }
 
   const params = new URLSearchParams(window.location.search)
 
-  let selectedClick = null
-
-  // Google normally provides only one identifier. This order is the
-  // deterministic fallback if a malformed URL contains more than one.
-  for (const key of CLICK_ID_KEYS) {
-    const value = params.get(key)
-
-    if (value && value.length <= MAX_CLICK_ID_LENGTH) {
-      selectedClick = { key, value }
-      break
-    }
-  }
+  const selectedClick = CLICK_ID_KEYS
+    .map(type => ({
+      type,
+      value: params.get(type),
+    }))
+    .find(
+      ({ value }) =>
+        value
+        && value.trim().length > 0
+        && value.length <= MAX_CLICK_ID_LENGTH,
+    )
 
-  // Organic/direct visit: preserve any attribution already stored.
+  // 没有新的 Google Ads 点击参数时，保留现有归因。
   if (!selectedClick) {
     return
   }
 
-  const selectedCookieName
-    = `${CLICK_COOKIE_PREFIX}${selectedClick.key}`
-
+  const cookieName = `${COOKIE_PREFIX}${selectedClick.type}`
   const isSameClick
-    = readCookie(selectedCookieName) === selectedClick.value
+    = readCookie(cookieName) === selectedClick.value
 
+  // 同一次点击：不刷新 90 天有效期，只清除其他类型的 click ID。
   if (isSameClick) {
-    // Remove stale identifiers of another type, but don't refresh this
-    // click's 90-day lifetime merely because the page was reloaded.
-    for (const key of CLICK_ID_KEYS) {
-      if (key !== selectedClick.key) {
-        deleteCookie(`${CLICK_COOKIE_PREFIX}${key}`)
+    for (const type of CLICK_ID_KEYS) {
+      if (type !== selectedClick.type) {
+        deleteCookie(`${COOKIE_PREFIX}${type}`)
       }
     }
 
-    const existingCapturedAt = Number(
-      readCookie(CAPTURED_AT_COOKIE_NAME),
-    )
+    const capturedAt = Number(readCookie(CAPTURED_AT_COOKIE))
 
-    // Migration path for cookies created by the previous script.
-    if (
-      !Number.isFinite(existingCapturedAt)
-      || existingCapturedAt <= 0
-    ) {
-      writeCookie(CAPTURED_AT_COOKIE_NAME, String(Date.now()))
+    if (!Number.isInteger(capturedAt) || capturedAt <= 0) {
+      writeCookie(CAPTURED_AT_COOKIE, String(Date.now()))
     }
 
     return
   }
 
-  // A genuinely new Google Ads click replaces the previous attribution.
-  for (const key of CLICK_ID_KEYS) {
-    deleteCookie(`${CLICK_COOKIE_PREFIX}${key}`)
+  // 新点击替换旧归因。
+  for (const type of CLICK_ID_KEYS) {
+    deleteCookie(`${COOKIE_PREFIX}${type}`)
   }
-  deleteCookie(CAPTURED_AT_COOKIE_NAME)
 
-  writeCookie(selectedCookieName, selectedClick.value)
-  writeCookie(CAPTURED_AT_COOKIE_NAME, String(Date.now()))
+  deleteCookie(CAPTURED_AT_COOKIE)
+
+  const capturedAt = Date.now()
+
+  writeCookie(cookieName, selectedClick.value)
+  writeCookie(CAPTURED_AT_COOKIE, String(capturedAt))
 })()