add library management

src/lib/libraries.ts

@@ -1,12 +1,17 @@
 import path from 'path'
 import fs from 'fs'
-import type { Library } from '@/types'
+import type { Library, LibraryType } from '@/types'
 
 const CONFIG_PATH = path.resolve(process.cwd(), 'libraries.json')
+const CONFIG_TMP = CONFIG_PATH + '.tmp'
 
 export function getLibraries(): Library[] {
-  const raw = fs.readFileSync(CONFIG_PATH, 'utf-8')
-  return JSON.parse(raw) as Library[]
+  try {
+    const raw = fs.readFileSync(CONFIG_PATH, 'utf-8')
+    return JSON.parse(raw) as Library[]
+  } catch {
+    return []
+  }
 }
 
 export function getLibrary(id: string): Library | undefined {
@@ -36,3 +41,87 @@ export function resolveAndJail(libraryRoot: string, subpath: string): string {
   }
   return resolved
 }
+
+/**
+ * Slugifies a name into a URL-safe id.
+ * e.g. "My Games Library" → "my-games-library"
+ */
+function slugify(name: string): string {
+  return name
+    .toLowerCase()
+    .trim()
+    .replace(/[^a-z0-9\s-]/g, '')
+    .replace(/\s+/g, '-')
+    .replace(/-+/g, '-')
+    .replace(/^-|-$/g, '')
+}
+
+/**
+ * Atomically writes the library list to disk.
+ */
+function writeLibraries(libraries: Library[]): void {
+  const json = JSON.stringify(libraries, null, 2) + '\n'
+  fs.writeFileSync(CONFIG_TMP, json, 'utf-8')
+  fs.renameSync(CONFIG_TMP, CONFIG_PATH)
+}
+
+/**
+ * Adds a new library. Validates the path exists as a directory.
+ * Throws a descriptive Error on failure.
+ */
+export function addLibrary(name: string, libraryPath: string, type: LibraryType): Library {
+  const trimmedName = name.trim()
+  const trimmedPath = libraryPath.trim()
+
+  if (!trimmedName) throw new Error('Name is required.')
+  if (!trimmedPath) throw new Error('Path is required.')
+
+  // Validate the path exists and is a directory
+  const resolved = path.isAbsolute(trimmedPath)
+    ? trimmedPath
+    : path.resolve(process.cwd(), trimmedPath)
+
+  let stat: fs.Stats
+  try {
+    stat = fs.statSync(resolved)
+  } catch {
+    throw new Error(`Path does not exist: ${trimmedPath}`)
+  }
+  if (!stat.isDirectory()) {
+    throw new Error(`Path is not a directory: ${trimmedPath}`)
+  }
+
+  const libraries = getLibraries()
+
+  // Generate a unique id
+  const baseId = slugify(trimmedName) || 'library'
+  let id = baseId
+  let suffix = 2
+  while (libraries.some((lib) => lib.id === id)) {
+    id = `${baseId}-${suffix++}`
+  }
+
+  // Reject exact duplicate names (same name, case-insensitive)
+  const duplicate = libraries.find(
+    (lib) => lib.name.toLowerCase() === trimmedName.toLowerCase()
+  )
+  if (duplicate) {
+    throw new Error(`A library named "${trimmedName}" already exists.`)
+  }
+
+  const newLibrary: Library = { id, name: trimmedName, path: trimmedPath, type }
+  writeLibraries([...libraries, newLibrary])
+  return newLibrary
+}
+
+/**
+ * Removes a library by id. Returns true if removed, false if not found.
+ */
+export function removeLibrary(id: string): boolean {
+  const libraries = getLibraries()
+  const index = libraries.findIndex((lib) => lib.id === id)
+  if (index === -1) return false
+  const updated = libraries.filter((lib) => lib.id !== id)
+  writeLibraries(updated)
+  return true
+}