feat(SW-189): added translations and some minor changes

utils/map.ts

@@ -0,0 +1,88 @@
+import crypto from "node:crypto"
+
+// Helper function to calculate the latitude offset
+export function calculateLatWithOffset(
+  latitude: number,
+  offsetPx: number,
+  zoomLevel: number
+): number {
+  const earthCircumference = 40075017 // Earth's circumference in meters
+  const tileSize = 256 // Height of a tile in pixels (standard in Google Maps)
+
+  // Calculate ground resolution (meters per pixel) at the given latitude and zoom level
+  const groundResolution =
+    (earthCircumference * Math.cos((latitude * Math.PI) / 180)) /
+    (tileSize * Math.pow(2, zoomLevel))
+
+  // Calculate the number of meters for the given offset in pixels
+  const metersOffset = groundResolution * offsetPx
+
+  // Convert the meters offset into a latitude offset (1 degree latitude is ~111,320 meters)
+  const latOffset = metersOffset / 111320
+
+  // Return the new latitude by subtracting the offset
+  return latitude - latOffset
+}
+
+/**
+ * Util functions taken from https://developers.google.com/maps/documentation/maps-static/digital-signature#sample-code-for-url-signing
+ * Used to sign the URL for the Google Static Maps API.
+ */
+
+/**
+ * Convert from 'web safe' base64 to true base64.
+ *
+ * @param  {string} safeEncodedString The code you want to translate
+ *                                    from a web safe form.
+ * @return {string}
+ */
+function removeWebSafe(safeEncodedString: string) {
+  return safeEncodedString.replace(/-/g, "+").replace(/_/g, "/")
+}
+
+/**
+ * Convert from true base64 to 'web safe' base64
+ *
+ * @param  {string} encodedString The code you want to translate to a
+ *                                web safe form.
+ * @return {string}
+ */
+function makeWebSafe(encodedString: string) {
+  return encodedString.replace(/\+/g, "-").replace(/\//g, "_")
+}
+
+/**
+ * Takes a base64 code and decodes it.
+ *
+ * @param  {string} code The encoded data.
+ * @return {string}
+ */
+function decodeBase64Hash(code: string) {
+  return Buffer.from(code, "base64")
+}
+
+/**
+ * Takes a key and signs the data with it.
+ *
+ * @param  {string} key  Your unique secret key.
+ * @param  {string} data The url to sign.
+ * @return {string}
+ */
+function encodeBase64Hash(key: Buffer, data: string) {
+  return crypto.createHmac("sha1", key).update(data).digest("base64")
+}
+
+/**
+ * Sign a URL using a secret key.
+ *
+ * @param  {URL} url   The url you want to sign.
+ * @param  {string} secret Your unique secret key.
+ * @return {string}
+ */
+export function getUrlWithSignature(url: URL, secret = "") {
+  const path = url.pathname + url.search
+  const safeSecret = decodeBase64Hash(removeWebSafe(secret))
+  const hashedSignature = makeWebSafe(encodeBase64Hash(safeSecret, path))
+
+  return `${url.toString()}&signature=${hashedSignature}`
+}