fix: validate texture asset names server-side

lib/asset-naming.ts

@@ -29,6 +29,44 @@ export function getForbiddenAssetFamilyAlias(value: string): AssetFamily | undef
   return FORBIDDEN_ASSET_FAMILY_ALIASES.get(value.toLowerCase())
 }
 
+function getFileStem(filename: string) {
+  return filename.replace(/\.[^.]+$/, '')
+}
+
+export function getTextureNamingError(filename: string) {
+  const stem = getFileStem(filename)
+  const [prefix, ...targetParts] = stem.split('_')
+  const family = getAssetFamily(prefix)
+  const extension = filename.split('.').pop()
+
+  if (family && targetParts.every(Boolean)) return null
+
+  const aliasSuggestion = getForbiddenAssetFamilyAlias(prefix)
+
+  if (aliasSuggestion && targetParts.every(Boolean)) {
+    const target = targetParts.join('_')
+    return `Convention invalide : ${filename}. Utilisez ${aliasSuggestion}_${target}.${extension} pour cibler "${target}", ou ${aliasSuggestion}.${extension} pour tout le modele.`
+  }
+
+  const reversedParts = stem.split('_')
+  const reversedFamily = reversedParts.length > 1 ? getAssetFamily(reversedParts[reversedParts.length - 1]) : undefined
+  const reversedAliasSuggestion = reversedParts.length > 1
+    ? getForbiddenAssetFamilyAlias(reversedParts[reversedParts.length - 1])
+    : undefined
+
+  if (reversedFamily) {
+    const target = reversedParts.slice(0, -1).join('_')
+    return `Convention invalide : ${filename}. Utilisez ${reversedFamily}_${target}.${extension} pour cibler "${target}", ou ${reversedFamily}.${extension} pour tout le modele.`
+  }
+
+  if (reversedAliasSuggestion) {
+    const target = reversedParts.slice(0, -1).join('_')
+    return `Convention invalide : ${filename}. Utilisez ${reversedAliasSuggestion}_${target}.${extension} pour cibler "${target}", ou ${reversedAliasSuggestion}.${extension} pour tout le modele.`
+  }
+
+  return `Asset inconnu : ${filename}. Familles autorisees : ${formatAssetFamilies()}. Utilisez asset.png pour tout le modele ou asset_objet.png pour cibler un objet.`
+}
+
 export function formatAssetFamilies() {
   return ASSET_FAMILIES.join(', ')
 }