feat(desktop): unify folder drag-and-drop across runtimes

packages/ui/src/lib/native/desktop-file-drop.ts

@@ -0,0 +1,155 @@
+import { getLogger } from "../logger"
+import { runtimeEnv } from "../runtime-env"
+
+const log = getLogger("actions")
+
+type NativeFolderDropState = "enter" | "leave"
+
+interface TauriFolderDropPayload {
+  paths?: unknown
+}
+
+function normalizePathList(input: unknown): string[] {
+  if (!Array.isArray(input)) {
+    return []
+  }
+  return input.filter((value): value is string => typeof value === "string" && value.trim().length > 0)
+}
+
+function getFilePath(file: File): string | null {
+  if (typeof file.path === "string" && file.path.trim().length > 0) {
+    return file.path
+  }
+  if (runtimeEnv.host === "electron") {
+    const electronPath = (window as Window & { electronAPI?: ElectronAPI }).electronAPI?.getPathForFile?.(file)
+    if (typeof electronPath === "string" && electronPath.trim().length > 0) {
+      return electronPath
+    }
+  }
+  return null
+}
+
+async function resolveElectronDirectoryPaths(paths: string[]): Promise<string[]> {
+  const api = (window as Window & { electronAPI?: ElectronAPI }).electronAPI
+  if (!api?.getDirectoryPaths || paths.length === 0) {
+    return []
+  }
+  try {
+    return await api.getDirectoryPaths(paths)
+  } catch (error) {
+    log.error("[native] failed to validate dropped directory paths", error)
+    return []
+  }
+}
+
+export function supportsDesktopFolderDrop(): boolean {
+  return runtimeEnv.platform === "desktop" && runtimeEnv.host !== "web"
+}
+
+export function containsFileDrop(event: DragEvent): boolean {
+  const types = event.dataTransfer?.types
+  if (!types) {
+    return false
+  }
+  return Array.from(types).includes("Files")
+}
+
+export function extractDroppedDirectoryPaths(event: DragEvent): string[] {
+  const dataTransfer = event.dataTransfer
+  if (!dataTransfer) {
+    return []
+  }
+
+  const directoryHints = new Set<string>()
+  for (const item of Array.from(dataTransfer.items ?? [])) {
+    if (item.kind !== "file") {
+      continue
+    }
+    const entry = item.webkitGetAsEntry?.()
+    if (!entry?.isDirectory) {
+      continue
+    }
+    const file = item.getAsFile()
+    const filePath = file ? getFilePath(file) : null
+    if (filePath) {
+      directoryHints.add(filePath)
+    }
+  }
+
+  const paths = new Set<string>()
+  for (const file of Array.from(dataTransfer.files ?? [])) {
+    const filePath = getFilePath(file)
+    if (!filePath) {
+      continue
+    }
+    if (directoryHints.size > 0 && !directoryHints.has(filePath)) {
+      continue
+    }
+    paths.add(filePath)
+  }
+
+  return Array.from(paths)
+}
+
+export async function normalizeDroppedDirectoryPaths(paths: string[]): Promise<string[]> {
+  const uniquePaths = Array.from(new Set(paths.filter((path) => typeof path === "string" && path.trim().length > 0)))
+  if (uniquePaths.length === 0) {
+    return []
+  }
+  if (runtimeEnv.host === "electron") {
+    return resolveElectronDirectoryPaths(uniquePaths)
+  }
+  return uniquePaths
+}
+
+export async function listenForNativeFolderDrops(onDrop: (paths: string[]) => void): Promise<() => void> {
+  if (runtimeEnv.host !== "tauri") {
+    return () => {}
+  }
+
+  const eventApi = window.__TAURI__?.event
+  if (!eventApi?.listen) {
+    return () => {}
+  }
+
+  try {
+    const unlisten = await eventApi.listen("desktop:folder-drop", (event) => {
+      const payload = (event.payload ?? {}) as TauriFolderDropPayload
+      const paths = normalizePathList(payload.paths)
+      if (paths.length > 0) {
+        onDrop(paths)
+      }
+    })
+    return () => {
+      unlisten()
+    }
+  } catch (error) {
+    log.error("[native] failed to listen for folder-drop event", error)
+    return () => {}
+  }
+}
+
+export async function listenForNativeFolderDropState(onState: (state: NativeFolderDropState) => void): Promise<() => void> {
+  if (runtimeEnv.host !== "tauri") {
+    return () => {}
+  }
+
+  const eventApi = window.__TAURI__?.event
+  if (!eventApi?.listen) {
+    return () => {}
+  }
+
+  try {
+    const [unlistenEnter, unlistenLeave] = await Promise.all([
+      eventApi.listen("desktop:folder-drag-enter", () => onState("enter")),
+      eventApi.listen("desktop:folder-drag-leave", () => onState("leave")),
+    ])
+    return () => {
+      unlistenEnter()
+      unlistenLeave()
+    }
+  } catch (error) {
+    log.error("[native] failed to listen for folder-drop state", error)
+    return () => {}
+  }
+}