feat: use canonical diensten root

src/dienstService.js

@@ -3,11 +3,31 @@ const path = require('path')
 
 let dienstenCache = null
 
+function getDienstenDir() {
+  if (!process.env.DIENSTEN_DIR) {
+    throw new Error('DIENSTEN_DIR is required; configure the canonical Whatsapp_Dienst/diensten directory')
+  }
+  return path.resolve(process.env.DIENSTEN_DIR)
+}
+
 function loadDiensten() {
   if (dienstenCache) return dienstenCache
-  const jsonPath = process.env.DIENSTEN_JSON
-  const raw = fs.readFileSync(jsonPath, 'utf-8')
-  dienstenCache = JSON.parse(raw)
+
+  const dienstenDir = getDienstenDir()
+  const jsonPath = path.join(dienstenDir, 'dienst-tijden.json')
+  let raw
+  try {
+    raw = fs.readFileSync(jsonPath, 'utf-8')
+  } catch (err) {
+    throw new Error(`Failed to read canonical diensten JSON at ${jsonPath}: ${err.message}`)
+  }
+
+  try {
+    dienstenCache = JSON.parse(raw)
+  } catch (err) {
+    throw new Error(`Failed to parse canonical diensten JSON at ${jsonPath}: ${err.message}`)
+  }
+
   return dienstenCache
 }
 
@@ -17,7 +37,7 @@ function findDienst(dienstnummer) {
 }
 
 function getPngFilePaths(dienst) {
-  const pngDir = process.env.DIENSTEN_PNG
+  const pngDir = path.join(getDienstenDir(), 'png')
   return dienst.paginas.map(p => path.join(pngDir, p.bestandsnaam))
 }