Codex/review repository code for errors

lib/api.ts

@@ -7,10 +7,7 @@ import { WBNB_ADDRESS } from '@/constants'
 import { getRandomElementFromArray } from '@/lib/utils'
 
 const client = axios.create({
-  baseURL: 'https://api.etherscan.io',
-  params: {
-    chainId: 56,
-  },
+  baseURL: 'https://api.bscscan.com/api',
 })
 
 client.interceptors.request.use(
@@ -92,7 +89,7 @@ export async function getTokenPrice({ symbol, address }: { symbol: string, addre
 }
 
 export async function getBlockNumberByTimestamp(timestamp: number) {
-  const res = await client.get('/v2/api', {
+  const res = await client.get('', {
     params: {
       module: 'block',
       action: 'getblocknobytime',
@@ -129,7 +126,7 @@ export async function getTransactions<T extends keyof TransactionActionMap>({
   startblock?: number
   endblock?: number
 }): Promise<TransactionActionMap[T][]> {
-  const res = await client.get<{ result: TransactionActionMap[T][] }>('/v2/api', {
+  const res = await client.get<{ result: TransactionActionMap[T][] }>('', {
     params: {
       module: 'account',
       action,

middleware.ts

@@ -5,14 +5,61 @@ export function middleware(request: NextRequest) {
   if (request.nextUrl.pathname.startsWith('/api/')) {
     const origin = request.headers.get('origin')
     const referer = request.headers.get('referer')
-    const allowedDomains = ['http://localhost:3000', 'https://bn-alpha.site', 'https://www.bn-alpha.site']
-    const isValidOrigin = origin && allowedDomains.includes(origin)
-    const isValidReferer = referer && allowedDomains.some(domain => referer.startsWith(domain))
+    const host = request.headers.get('host')
+    const forwardedHost = request.headers.get('x-forwarded-host')
+    const forwardedProto = request.headers.get('x-forwarded-proto')
+    const defaultAllowedDomains = ['http://localhost:3000', 'https://bn-alpha.site', 'https://www.bn-alpha.site']
+    const dynamicAllowedDomains = new Set(defaultAllowedDomains)
 
-    if (!isValidOrigin && !isValidReferer) {
-      return NextResponse.json({ error: 'Forbidden' }, { status: 403 })
+    const normalizeProtocol = (protocol?: string | null) => {
+      if (!protocol)
+        return null
+      return protocol.endsWith(':') ? protocol.slice(0, -1) : protocol
+    }
+
+    const appendOrigin = (hostValue?: string | null, protocol?: string | null) => {
+      if (!hostValue)
+        return
+      const normalizedProtocol = normalizeProtocol(protocol) ?? 'https'
+      const baseHost = hostValue.split(',')[0]?.trim()
+      if (!baseHost)
+        return
+      dynamicAllowedDomains.add(`${normalizedProtocol}://${baseHost}`)
     }
 
+    if (request.nextUrl.origin)
+      dynamicAllowedDomains.add(request.nextUrl.origin)
+
+    appendOrigin(request.nextUrl.host, request.nextUrl.protocol)
+    appendOrigin(host, forwardedProto ?? request.nextUrl.protocol)
+    appendOrigin(forwardedHost, forwardedProto)
+
+    const allowedDomains = Array.from(dynamicAllowedDomains)
+
+    const getRefererOrigin = (value?: string | null) => {
+      if (!value)
+        return null
+      try {
+        return new URL(value).origin
+      }
+      catch {
+        return null
+      }
+    }
+
+    const refererOrigin = getRefererOrigin(referer)
+    const inferredSameHostOrigin = request.nextUrl.host
+      ? `${normalizeProtocol(request.nextUrl.protocol) ?? 'https'}://${request.nextUrl.host}`
+      : null
+
+    const isValidOrigin = !!origin && dynamicAllowedDomains.has(origin)
+    const isValidReferer = !!refererOrigin && dynamicAllowedDomains.has(refererOrigin)
+    const isMissingCorsHeaders = !origin && !referer
+    const isSameHostRequest = isMissingCorsHeaders && !!inferredSameHostOrigin && dynamicAllowedDomains.has(inferredSameHostOrigin)
+
+    if (!isValidOrigin && !isValidReferer && !isSameHostRequest)
+      return NextResponse.json({ error: 'Forbidden' }, { status: 403 })
+
     const userAgent = request.headers.get('user-agent')
     const blockedUserAgents = ['curl/', 'wget/', 'python-requests/', 'postman', 'insomnia', 'httpie']
 
@@ -22,8 +69,14 @@ export function middleware(request: NextRequest) {
 
     const response = NextResponse.next()
 
+    const fallbackOrigin = request.nextUrl.origin ?? inferredSameHostOrigin ?? allowedDomains[0]
+    const corsOrigin = (isValidOrigin && origin)
+      || (isValidReferer && refererOrigin)
+      || (isSameHostRequest && inferredSameHostOrigin)
+      || fallbackOrigin
+
     // CORS Headers
-    response.headers.set('Access-Control-Allow-Origin', origin || allowedDomains[0])
+    response.headers.set('Access-Control-Allow-Origin', corsOrigin)
     response.headers.set('Access-Control-Allow-Methods', 'GET, POST, OPTIONS')
     response.headers.set('Access-Control-Allow-Headers', 'Content-Type, Authorization, X-API-Key')
     response.headers.set('Access-Control-Max-Age', '86400')