feat: move currency converter to server

app/api/currency/route.ts

@@ -0,0 +1,66 @@
+import { format } from "date-fns"
+import { NextRequest, NextResponse } from "next/server"
+
+type HistoricRate = {
+  currency: string
+  rate: number
+  inverse: number
+}
+
+export async function GET(request: NextRequest) {
+  try {
+    const searchParams = request.nextUrl.searchParams
+    const fromCurrency = searchParams.get("from")
+    const toCurrency = searchParams.get("to")
+    const dateParam = searchParams.get("date")
+
+    if (!fromCurrency || !toCurrency || !dateParam) {
+      return NextResponse.json({ error: "Missing required parameters: from, to, date" }, { status: 400 })
+    }
+
+    const date = new Date(dateParam)
+    if (isNaN(date.getTime())) {
+      return NextResponse.json({ error: "Invalid date format" }, { status: 400 })
+    }
+
+    const formattedDate = format(date, "yyyy-MM-dd")
+    const url = `https://www.xe.com/currencytables/?from=${fromCurrency}&date=${formattedDate}`
+
+    const response = await fetch(url)
+
+    if (!response.ok) {
+      return NextResponse.json(
+        { error: `Failed to fetch currency data: ${response.status}` },
+        { status: response.status }
+      )
+    }
+
+    const html = await response.text()
+
+    // Extract the JSON data from the __NEXT_DATA__ script tag
+    const scriptTagRegex = /<script id="__NEXT_DATA__" type="application\/json">([\s\S]*?)<\/script>/
+    const match = html.match(scriptTagRegex)
+
+    if (!match || !match[1]) {
+      return NextResponse.json({ error: "Could not find currency data in the page" }, { status: 500 })
+    }
+
+    const jsonData = JSON.parse(match[1])
+    const historicRates = jsonData.props.pageProps.historicRates as HistoricRate[]
+
+    if (!historicRates || historicRates.length === 0) {
+      return NextResponse.json({ error: "No currency rates found for the specified date" }, { status: 404 })
+    }
+
+    const rate = historicRates.find((rate) => rate.currency === toCurrency)
+
+    if (!rate) {
+      return NextResponse.json({ error: `Currency rate not found for ${toCurrency}` }, { status: 404 })
+    }
+
+    return NextResponse.json({ rate: rate.rate })
+  } catch (error) {
+    console.error("Currency API error:", error)
+    return NextResponse.json({ error: "Internal server error" }, { status: 500 })
+  }
+}