Fix UniFile.fromUri for children of tree uri

app/src/main/kotlin/com/hippo/unifile/DocumentsContractApi21.kt

@@ -15,20 +15,18 @@
  */
 package com.hippo.unifile
 
-import android.content.Context
 import android.net.Uri
 import android.provider.DocumentsContract
 import splitties.init.appCtx
 
 object DocumentsContractApi21 {
-    private const val PATH_DOCUMENT = "document"
-    private const val PATH_TREE = "tree"
     private val resolver = appCtx.contentResolver
     private val projection = arrayOf(
         DocumentsContract.Document.COLUMN_DOCUMENT_ID,
         DocumentsContract.Document.COLUMN_DISPLAY_NAME,
         DocumentsContract.Document.COLUMN_MIME_TYPE,
     )
+
     fun createFile(self: Uri, mimeType: String, displayName: String) = runCatching {
         DocumentsContract.createDocument(resolver, self, mimeType, displayName)
     }.getOrNull()
@@ -38,22 +36,14 @@ object DocumentsContractApi21 {
     fun prepareTreeUri(treeUri: Uri?): Uri {
         return DocumentsContract.buildDocumentUriUsingTree(
             treeUri,
-            DocumentsContract.getTreeDocumentId(treeUri),
+            DocumentsContract.getDocumentId(treeUri),
         )
     }
 
-    fun getTreeDocumentPath(documentUri: Uri): String {
-        val paths = documentUri.pathSegments
-        if (paths.size >= 4 && PATH_TREE == paths[0] && PATH_DOCUMENT == paths[2]) {
-            return paths[3]
-        }
-        error("Invalid URI: $documentUri")
-    }
-
     fun buildChildUri(uri: Uri, displayName: String): Uri {
         return DocumentsContract.buildDocumentUriUsingTree(
             uri,
-            getTreeDocumentPath(uri) + "/" + displayName,
+            DocumentsContract.getDocumentId(uri) + "/" + displayName,
         )
     }
 
@@ -70,7 +60,7 @@ object DocumentsContractApi21 {
         }
     }
 
-    fun renameTo(context: Context, self: Uri, displayName: String) = runCatching {
-        DocumentsContract.renameDocument(context.contentResolver, self, displayName)
+    fun renameTo(self: Uri, displayName: String) = runCatching {
+        DocumentsContract.renameDocument(resolver, self, displayName)
     }.getOrNull()
 }

app/src/main/kotlin/com/hippo/unifile/MediaFile.kt

@@ -18,7 +18,7 @@ package com.hippo.unifile
 import android.net.Uri
 import java.io.IOException
 
-class MediaFile(override val uri: Uri) : UniFile(null) {
+class MediaFile(override val uri: Uri) : UniFile() {
     override fun createFile(displayName: String) = null
 
     override fun createDirectory(displayName: String) = null

app/src/main/kotlin/com/hippo/unifile/RawFile.kt

@@ -24,8 +24,7 @@ import eu.kanade.tachiyomi.util.system.logcat
 import java.io.File
 import java.util.Locale
 
-class RawFile(parent: UniFile?, private var file: File) : UniFile(parent) {
-    private val parent = parent as? RawFile
+class RawFile(private val parent: RawFile?, private var file: File) : UniFile() {
 
     private var cachePresent = false
     private val allChildren by lazy {

app/src/main/kotlin/com/hippo/unifile/SingleDocumentFile.kt

@@ -17,7 +17,7 @@ package com.hippo.unifile
 
 import android.net.Uri
 
-class SingleDocumentFile(parent: UniFile?, override val uri: Uri) : UniFile(parent) {
+class SingleDocumentFile(override val uri: Uri) : UniFile() {
 
     override fun createFile(displayName: String) = null
 

app/src/main/kotlin/com/hippo/unifile/TreeDocumentFile.kt

@@ -18,19 +18,16 @@ package com.hippo.unifile
 import android.net.Uri
 import android.provider.DocumentsContract.Document.MIME_TYPE_DIR
 import android.webkit.MimeTypeMap
-import eu.kanade.tachiyomi.util.system.logcat
-import splitties.init.appCtx
 
 class TreeDocumentFile(
-    parent: UniFile?,
+    private val parent: UniFile?,
     override var uri: Uri,
     override var name: String = getFilenameForUri(uri),
     mimeType: String? = null,
-) : UniFile(parent) {
+) : UniFile() {
     private var cachePresent = false
     private val allChildren by lazy {
         cachePresent = true
-        logcat { "Directory lookup cache created for $name" }
         DocumentsContractApi21.listFiles(uri).mapTo(mutableListOf()) { (uri, name, mimeType) ->
             TreeDocumentFile(this, uri, name, mimeType)
         }
@@ -98,7 +95,6 @@ class TreeDocumentFile(
     override fun ensureDir(): Boolean {
         if (isDirectory) return true
         if (isFile) return false
-        val parent = parentFile
         return if (parent != null && parent.ensureDir()) {
             parent.createDirectory(name) != null
         } else {
@@ -109,7 +105,6 @@ class TreeDocumentFile(
     override fun ensureFile(): Boolean {
         if (isFile) return true
         if (isDirectory) return false
-        val parent = parentFile
         return if (parent != null && parent.ensureDir()) {
             parent.createFile(name) != null
         } else {
@@ -135,7 +130,7 @@ class TreeDocumentFile(
     }
 
     override fun renameTo(displayName: String): Boolean {
-        val result = DocumentsContractApi21.renameTo(appCtx, uri, displayName)
+        val result = DocumentsContractApi21.renameTo(uri, displayName)
         if (result != null) {
             uri = result
             name = displayName

app/src/main/kotlin/com/hippo/unifile/UniFile.kt

@@ -28,7 +28,7 @@ import splitties.init.appCtx
  * In Android files can be accessed via [java.io.File] and [android.net.Uri].
  * The UniFile is designed to emulate File interface for both File and Uri.
  */
-abstract class UniFile internal constructor(private val parent: UniFile?) {
+sealed class UniFile {
     /**
      * Create a new file as a direct child of this directory.
      *
@@ -79,21 +79,6 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
      */
     abstract val type: String?
 
-    /**
-     * Return the parent file of this file. Only defined inside of the
-     * user-selected tree; you can never escape above the top of the tree.
-     *
-     *
-     * The underlying [android.provider.DocumentsProvider] only defines a
-     * forward mapping from parent to child, so the reverse mapping of child to
-     * parent offered here is purely a convenience method, and it may be
-     * incorrect if the underlying tree structure changes.
-     *
-     * @return parent of the file, or null if it is the top of the file tree
-     */
-    val parentFile: UniFile?
-        get() = parent
-
     /**
      * Indicates if this file represents a *directory*.
      *
@@ -235,7 +220,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
     companion object {
         fun fromFile(file: File) = RawFile(null, file)
 
-        private fun fromSingleUri(singleUri: Uri) = SingleDocumentFile(null, singleUri)
+        private fun fromSingleUri(singleUri: Uri) = SingleDocumentFile(singleUri)
 
         private fun fromTreeUri(treeUri: Uri) = TreeDocumentFile(null, DocumentsContractApi21.prepareTreeUri(treeUri))