Implement lookup cache for UniFile (#545)

* Implement lookup cache for RawFile

* Implement lookup cache for TreeDocumentFile

* Drop unused UriHandler

* UniFile.subFile never return null

* Nonnull UniFile.fromFile

* SingleDocumentFile use appCtx

* TreeDocumentFile use appCtx

* MediaFile use appCtx

* Refine

* Refine

* Refine

* optimize TreeDocumentFile cache

* optimize RawFile cache

* Take care of dir lookup cache cause memleak

* Fixup

* Fixup

---------

Co-authored-by: GG Bond <whatever@tagkong.com>

app/src/main/kotlin/com/hippo/ehviewer/coil/DownloadThumbInterceptor.kt

@@ -8,7 +8,7 @@ import com.hippo.ehviewer.EhApplication.Companion.imageCache
 import com.hippo.ehviewer.download.downloadLocation
 import com.hippo.ehviewer.spider.DownloadInfoMagics.decodeMagicRequestOrUrl
 import com.hippo.ehviewer.util.sendTo
-import com.hippo.unifile.UniFile
+import com.hippo.unifile.asUniFile
 import eu.kanade.tachiyomi.util.lang.withIOContext
 
 object DownloadThumbInterceptor : Interceptor {
@@ -17,25 +17,22 @@ object DownloadThumbInterceptor : Interceptor {
         if (magicOrUrl != null) {
             val (url, location) = decodeMagicRequestOrUrl(magicOrUrl)
             if (location != null) {
-                val thumb = withIOContext { downloadLocation.subFile(location)?.subFile(".thumb") }
-                if (thumb != null) {
-                    if (withIOContext { thumb.isFile }) {
-                        val new = chain.request.newBuilder().data(thumb.uri.toString()).build()
-                        when (val result = chain.withRequest(new).proceed()) {
-                            is SuccessResult -> return result
-                            is ErrorResult -> withIOContext { thumb.delete() }
-                        }
+                val thumb = withIOContext { downloadLocation.subFile(location).subFile(".thumb") }
+                if (withIOContext { thumb.isFile }) {
+                    val new = chain.request.newBuilder().data(thumb.uri.toString()).build()
+                    when (val result = chain.withRequest(new).proceed()) {
+                        is SuccessResult -> return result
+                        is ErrorResult -> withIOContext { thumb.delete() }
                     }
-                    val new = chain.request.newBuilder().data(url).build()
-                    return chain.withRequest(new).proceed().also {
-                        if (it is SuccessResult) {
-                            withIOContext {
-                                if (thumb.ensureFile()) {
-                                    val key = requireNotNull(chain.request.memoryCacheKey)
-                                    imageCache.read(key) {
-                                        val cache = UniFile.fromFile(data.toFile())
-                                        requireNotNull(cache) sendTo thumb
-                                    }
+                }
+                val new = chain.request.newBuilder().data(url).build()
+                return chain.withRequest(new).proceed().also {
+                    if (it is SuccessResult) {
+                        withIOContext {
+                            if (thumb.ensureFile()) {
+                                val key = requireNotNull(chain.request.memoryCacheKey)
+                                imageCache.read(key) {
+                                    data.asUniFile() sendTo thumb
                                 }
                             }
                         }

app/src/main/kotlin/com/hippo/ehviewer/download/DownloadManager.kt

@@ -46,6 +46,8 @@ import com.hippo.ehviewer.util.assertNotMainThread
 import com.hippo.ehviewer.util.mapNotNull
 import com.hippo.ehviewer.util.runAssertingNotMainThread
 import com.hippo.unifile.UniFile
+import com.hippo.unifile.asUniFile
+import com.hippo.unifile.asUniFileOrNull
 import eu.kanade.tachiyomi.util.lang.launchIO
 import eu.kanade.tachiyomi.util.lang.withIOContext
 import kotlinx.coroutines.coroutineScope
@@ -53,7 +55,6 @@ import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.asSharedFlow
 import kotlinx.coroutines.flow.transform
 import kotlinx.coroutines.launch
-import splitties.init.appCtx
 import splitties.preferences.edit
 
 object DownloadManager : OnSpiderListener {
@@ -1017,16 +1018,14 @@ object DownloadManager : OnSpiderListener {
 
 var downloadLocation: UniFile
     get() = with(Settings) {
-        UniFile.fromUri(
-            appCtx,
-            Uri.Builder().apply {
-                scheme(downloadScheme)
-                encodedAuthority(downloadAuthority)
-                encodedPath(downloadPath)
-                encodedQuery(downloadQuery)
-                encodedFragment(downloadFragment)
-            }.build(),
-        ) ?: UniFile.fromFile(AppConfig.defaultDownloadDir)!!
+        val uri = Uri.Builder().apply {
+            scheme(downloadScheme)
+            encodedAuthority(downloadAuthority)
+            encodedPath(downloadPath)
+            encodedQuery(downloadQuery)
+            encodedFragment(downloadFragment)
+        }.build()
+        uri.asUniFileOrNull() ?: requireNotNull(AppConfig.defaultDownloadDir).asUniFile()
     }
     set(value) = with(value.uri) {
         Settings.edit {

app/src/main/kotlin/com/hippo/ehviewer/gallery/ArchivePageLoader.kt

@@ -171,7 +171,7 @@ class ArchivePageLoader(context: Context, private val uri: Uri, passwdProvider:
 
     override fun save(index: Int, dir: UniFile, filename: String): UniFile {
         val dst = dir.subFile(filename)
-        save(index, dst!!)
+        save(index, dst)
         return dst
     }
 

app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderDen.kt

@@ -30,6 +30,7 @@ import com.hippo.ehviewer.image.Image.UniFileSource
 import com.hippo.ehviewer.util.FileUtils
 import com.hippo.ehviewer.util.sendTo
 import com.hippo.unifile.UniFile
+import com.hippo.unifile.asUniFile
 import com.hippo.unifile.openOutputStream
 import io.ktor.client.plugins.onDownload
 import io.ktor.client.statement.HttpResponse
@@ -154,7 +155,7 @@ class SpiderDen(mGalleryInfo: GalleryInfo) {
             val key = getImageKey(mGid, index)
             return sCache.suspendEdit(key) {
                 metadata.toFile().writeText(ext)
-                fops(UniFile.fromFile(data.toFile())!!)
+                fops(data.asUniFile())
             }
         }
         return false
@@ -172,34 +173,28 @@ class SpiderDen(mGalleryInfo: GalleryInfo) {
     }
 
     fun saveToUniFile(index: Int, file: UniFile): Boolean {
-        file.openFileDescriptor("w").use { toFd ->
-            val key = getImageKey(mGid, index)
+        val key = getImageKey(mGid, index)
 
-            // Read from diskCache first
-            sCache.read(key) {
-                runCatching {
-                    UniFile.fromFile(data.toFile())!!.openFileDescriptor("r").use {
-                        it sendTo toFd
-                    }
-                    return true
-                }.onFailure {
-                    it.printStackTrace()
-                    return false
-                }
+        // Read from diskCache first
+        sCache.read(key) {
+            runCatching {
+                data.asUniFile() sendTo file
+                return true
+            }.onFailure {
+                it.printStackTrace()
+                return false
             }
+        }
 
-            // Read from download dir
-            downloadDir?.let { uniFile ->
-                runCatching {
-                    findImageFile(uniFile, index)?.openFileDescriptor("r")?.use {
-                        it sendTo toFd
-                    }
-                }.onFailure {
-                    it.printStackTrace()
-                    return false
-                }.onSuccess {
-                    return true
-                }
+        // Read from download dir
+        downloadDir?.let { uniFile ->
+            runCatching {
+                requireNotNull(findImageFile(uniFile, index)) sendTo file
+            }.onFailure {
+                it.printStackTrace()
+                return false
+            }.onSuccess {
+                return true
             }
         }
         return false
@@ -216,9 +211,8 @@ class SpiderDen(mGalleryInfo: GalleryInfo) {
             val key = getImageKey(mGid, index)
             val snapshot = sCache.openSnapshot(key)
             if (snapshot != null) {
-                val source = UniFile.fromFile(snapshot.data.toFile())!!
                 return object : UniFileSource, AutoCloseable by snapshot {
-                    override val source = source
+                    override val source = snapshot.data.asUniFile()
                 }
             }
         }

app/src/main/kotlin/com/hippo/ehviewer/spider/SpiderQueen.kt

@@ -313,7 +313,7 @@ class SpiderQueen private constructor(val galleryInfo: GalleryInfo) : CoroutineS
         if (STATE_FINISHED != state) {
             return null
         }
-        val dst = dir.subFile(filename) ?: return null
+        val dst = dir.subFile(filename)
         return if (!mSpiderDen.saveToUniFile(index, dst)) null else dst
     }
 

app/src/main/kotlin/com/hippo/ehviewer/ui/CommonOperations.kt

@@ -81,7 +81,7 @@ import moe.tarsin.coroutines.runSuspendCatching
 import splitties.init.appCtx
 
 private fun removeNoMediaFile(downloadDir: UniFile) {
-    val noMedia = downloadDir.subFile(".nomedia") ?: return
+    val noMedia = downloadDir.subFile(".nomedia")
     noMedia.delete()
 }
 

app/src/main/kotlin/com/hippo/ehviewer/ui/settings/DownloadScreen.kt

@@ -44,6 +44,7 @@ import com.hippo.ehviewer.ui.tools.observed
 import com.hippo.ehviewer.ui.tools.rememberedAccessor
 import com.hippo.ehviewer.util.AppConfig
 import com.hippo.unifile.UniFile
+import com.hippo.unifile.asUniFile
 import com.ramcosta.composedestinations.annotation.Destination
 import com.ramcosta.composedestinations.navigation.DestinationsNavigator
 import eu.kanade.tachiyomi.util.lang.launchNonCancellable
@@ -82,11 +83,9 @@ fun DownloadScreen(navigator: DestinationsNavigator) {
                     coroutineScope.launch {
                         context.runCatching {
                             contentResolver.takePersistableUriPermission(treeUri, FLAG_GRANT_READ_URI_PERMISSION or FLAG_GRANT_WRITE_URI_PERMISSION)
-                            UniFile.fromTreeUri(context, treeUri)!!.run {
-                                downloadLocationState = this
-                                coroutineScope.launchNonCancellable {
-                                    keepNoMediaFileStatus()
-                                }
+                            downloadLocationState = treeUri.asUniFile()
+                            coroutineScope.launchNonCancellable {
+                                keepNoMediaFileStatus()
                             }
                         }.onFailure {
                             launchSnackBar(cannotGetDownloadLocation)
@@ -105,7 +104,7 @@ fun DownloadScreen(navigator: DestinationsNavigator) {
                         .setMessage(file.uri.toString())
                         .setPositiveButton(R.string.pick_new_download_location) { _, _ -> selectDownloadDirLauncher.launch(null) }
                         .setNeutralButton(R.string.reset_download_location) { _, _ ->
-                            val uniFile = UniFile.fromFile(AppConfig.defaultDownloadDir)
+                            val uniFile = AppConfig.defaultDownloadDir?.asUniFile()
                             if (uniFile != null) {
                                 downloadLocationState = uniFile
                                 coroutineScope.launchNonCancellable { keepNoMediaFileStatus() }
@@ -160,7 +159,6 @@ fun DownloadScreen(navigator: DestinationsNavigator) {
                 summary = stringResource(id = R.string.settings_download_download_origin_image_summary),
                 value = Settings::downloadOriginImage,
             )
-            val restoreFailed = stringResource(id = R.string.settings_download_restore_failed)
             WorkPreference(
                 title = stringResource(id = R.string.settings_download_restore_download_items),
                 summary = stringResource(id = R.string.settings_download_restore_download_items_summary),
@@ -191,25 +189,21 @@ fun DownloadScreen(navigator: DestinationsNavigator) {
                     }.getOrNull()
                 }
                 runCatching {
-                    val result = downloadLocation.listFiles()?.mapNotNull { getRestoreItem(it) }?.apply {
+                    val result = downloadLocation.listFiles().mapNotNull { getRestoreItem(it) }.apply {
                         runSuspendCatching {
                             fillGalleryListByApi(this, EhUrl.referer)
                         }.onFailure {
                             it.printStackTrace()
                         }
                     }
-                    if (result == null) {
-                        launchSnackBar(restoreFailed)
+                    if (result.isEmpty()) {
+                        launchSnackBar(RESTORE_COUNT_MSG(restoreDirCount))
                     } else {
-                        if (result.isEmpty()) {
-                            launchSnackBar(RESTORE_COUNT_MSG(restoreDirCount))
-                        } else {
-                            val count = result.filterNot { it.title.isNullOrBlank() }.map {
-                                EhDB.putDownloadDirname(it.gid, it.dirname)
-                                DownloadManager.restoreDownload(it.galleryInfo, it.dirname)
-                            }.size
-                            launchSnackBar(RESTORE_COUNT_MSG(count + restoreDirCount))
-                        }
+                        val count = result.filterNot { it.title.isNullOrBlank() }.map {
+                            EhDB.putDownloadDirname(it.gid, it.dirname)
+                            DownloadManager.restoreDownload(it.galleryInfo, it.dirname)
+                        }.size
+                        launchSnackBar(RESTORE_COUNT_MSG(count + restoreDirCount))
                     }
                 }.onFailure {
                     it.printStackTrace()
@@ -233,7 +227,7 @@ fun DownloadScreen(navigator: DestinationsNavigator) {
                     return true
                 }
                 runSuspendCatching {
-                    val cnt = downloadLocation.listFiles()?.sumOf { clearFile(it).compareTo(false) } ?: 0
+                    val cnt = downloadLocation.listFiles().sumOf { clearFile(it).compareTo(false) }
                     launchSnackBar(FINAL_CLEAR_REDUNDANCY_MSG(cnt))
                 }.onFailure {
                     it.printStackTrace()

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

@@ -15,29 +15,27 @@
  */
 package com.hippo.unifile
 
-import android.content.Context
 import android.graphics.ImageDecoder
 import android.net.Uri
 import java.io.IOException
+import splitties.init.appCtx
 
-internal class MediaFile(context: Context, override val uri: Uri) : UniFile(null) {
-    private val mContext = context.applicationContext
-
+class MediaFile(override val uri: Uri) : UniFile(null) {
     override fun createFile(displayName: String) = null
 
     override fun createDirectory(displayName: String) = null
 
     override val name: String?
-        get() = MediaContract.getName(mContext, uri)
+        get() = MediaContract.getName(appCtx, uri)
     override val type: String?
-        get() = MediaContract.getType(mContext, uri)
+        get() = MediaContract.getType(appCtx, uri)
     override val isDirectory = false
     override val isFile: Boolean
-        get() = DocumentsContractApi19.isFile(mContext, uri)
+        get() = DocumentsContractApi19.isFile(appCtx, uri)
 
-    override fun lastModified() = MediaContract.lastModified(mContext, uri)
+    override fun lastModified() = MediaContract.lastModified(appCtx, uri)
 
-    override fun length() = MediaContract.length(mContext, uri)
+    override fun length() = MediaContract.length(appCtx, uri)
 
     override fun canRead() = isFile
 
@@ -55,28 +53,26 @@ internal class MediaFile(context: Context, override val uri: Uri) : UniFile(null
 
     override fun ensureFile() = isFile
 
-    override fun subFile(displayName: String) = null
+    override fun subFile(displayName: String) = error("MediaFile never have a children")
 
     override fun delete() = false
 
     override fun exists() = isFile
 
-    override fun listFiles() = null
+    override fun listFiles() = emptyList<MediaFile>()
 
     override fun findFirst(filter: (String) -> Boolean) = null
 
-    override fun findFile(displayName: String) = null
-
     override fun renameTo(displayName: String) = false
 
     override val imageSource: ImageDecoder.Source
-        get() = Contracts.getImageSource(mContext, uri)
+        get() = Contracts.getImageSource(appCtx, uri)
 
-    override fun openFileDescriptor(mode: String) = Contracts.openFileDescriptor(mContext, uri, mode)
+    override fun openFileDescriptor(mode: String) = Contracts.openFileDescriptor(appCtx, uri, mode)
 
     companion object {
-        fun isMediaUri(context: Context, uri: Uri): Boolean {
-            return null != MediaContract.getName(context, uri)
+        fun isMediaUri(uri: Uri): Boolean {
+            return null != MediaContract.getName(appCtx, uri)
         }
     }
 }

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

@@ -19,40 +19,45 @@ import android.graphics.ImageDecoder
 import android.net.Uri
 import android.os.Build
 import android.os.ParcelFileDescriptor
-import android.util.Log
 import android.webkit.MimeTypeMap
+import eu.kanade.tachiyomi.util.system.logcat
 import java.io.File
-import java.io.FileOutputStream
 import java.io.IOException
 import java.util.Locale
 
-internal class RawFile(parent: UniFile?, var mFile: File) : UniFile(parent) {
-    override fun createFile(displayName: String): UniFile? {
-        val target = File(mFile, displayName)
-        return if (target.exists()) {
-            if (target.isFile) {
-                RawFile(this, target)
-            } else {
-                null
-            }
-        } else {
-            runCatching {
-                FileOutputStream(target).use {}
-                RawFile(this, target)
-            }.getOrElse {
-                Log.w(TAG, "Failed to createFile $displayName: $it")
-                null
-            }
+class RawFile(parent: UniFile?, private var mFile: File) : UniFile(parent) {
+    val parent = parent as? RawFile
+
+    var cachePresent = false
+    private val allChildren by lazy {
+        val current = this
+        cachePresent = true
+        logcat { "Directory lookup cache created for $name" }
+        mutableListOf<RawFile>().apply {
+            val fs = mFile.listFiles()?.map { RawFile(current, it) }
+            if (fs != null) addAll(fs)
         }
     }
 
-    override fun createDirectory(displayName: String): UniFile? {
-        val target = File(mFile, displayName)
-        return if (target.isDirectory || target.mkdirs()) {
-            RawFile(this, target)
+    private fun popParentCacheIfPresent() = apply {
+        val present = parent?.cachePresent ?: false
+        if (present) parent?.allChildren?.add(this)
+    }
+
+    override fun createFile(displayName: String): UniFile? {
+        val target = RawFile(this, File(mFile, displayName))
+        if (target.exists()) {
+            if (target.isFile) return target
         } else {
-            null
+            if (target.ensureFile()) return target
         }
+        return null
+    }
+
+    override fun createDirectory(displayName: String): UniFile? {
+        val target = RawFile(this, File(mFile, displayName))
+        if (target.ensureDir()) return target
+        return null
     }
 
     override val uri: Uri
@@ -70,74 +75,48 @@ internal class RawFile(parent: UniFile?, var mFile: File) : UniFile(parent) {
     override val isFile: Boolean
         get() = mFile.isFile
 
-    override fun lastModified(): Long {
-        return mFile.lastModified()
-    }
+    override fun lastModified() = mFile.lastModified()
 
-    override fun length(): Long {
-        return mFile.length()
-    }
+    override fun length() = mFile.length()
 
-    override fun canRead(): Boolean {
-        return mFile.canRead()
-    }
+    override fun canRead() = mFile.canRead()
 
-    override fun canWrite(): Boolean {
-        return mFile.canWrite()
-    }
+    override fun canWrite() = mFile.canWrite()
 
     override fun ensureDir(): Boolean {
-        return mFile.isDirectory || mFile.mkdirs()
+        if (mFile.isDirectory) return true
+        if (mFile.mkdirs()) {
+            popParentCacheIfPresent()
+            return true
+        }
+        return false
     }
 
     override fun ensureFile(): Boolean {
-        return if (mFile.exists()) {
-            mFile.isFile
-        } else {
-            runCatching {
-                FileOutputStream(mFile).use {}
-                true
-            }.getOrDefault(false)
-        }
+        if (mFile.exists()) return mFile.isFile
+        parent?.ensureDir()
+        val success = mFile.createNewFile()
+        if (success) popParentCacheIfPresent()
+        return success
     }
 
-    override fun subFile(displayName: String): UniFile {
-        return RawFile(this, File(mFile, displayName))
-    }
+    override fun subFile(displayName: String) = RawFile(this, File(mFile, displayName))
 
-    override fun delete(): Boolean {
-        deleteContents(mFile)
-        return mFile.delete()
-    }
+    override fun delete() = mFile.deleteRecursively()
 
-    override fun exists(): Boolean {
-        return mFile.exists()
-    }
+    override fun exists() = mFile.exists()
 
-    override fun listFiles(): Array<UniFile>? {
-        val files = mFile.listFiles() ?: return null
-        return files.map { RawFile(this, it) }.toTypedArray()
-    }
+    override fun listFiles() = allChildren
 
-    override fun findFirst(filter: (String) -> Boolean) = mFile.listFiles { _, name ->
-        filter(name)
-    }?.firstOrNull()?.let {
-        RawFile(this, it)
-    }
-
-    override fun findFile(displayName: String): UniFile? {
-        val child = File(mFile, displayName)
-        return if (child.exists()) RawFile(this, child) else null
-    }
+    override fun findFirst(filter: (String) -> Boolean) = allChildren.firstOrNull { filter(it.name) }
 
     override fun renameTo(displayName: String): Boolean {
         val target = File(mFile.parentFile, displayName)
-        return if (mFile.renameTo(target)) {
+        if (mFile.renameTo(target)) {
             mFile = target
-            true
-        } else {
-            false
+            return true
         }
+        return false
     }
 
     override val imageSource: ImageDecoder.Source
@@ -149,39 +128,18 @@ internal class RawFile(parent: UniFile?, var mFile: File) : UniFile(parent) {
 
     override fun openFileDescriptor(mode: String): ParcelFileDescriptor {
         val md = ParcelFileDescriptor.parseMode(mode)
-        return ParcelFileDescriptor.open(mFile, md)
-            ?: throw IOException("Can't open ParcelFileDescriptor")
-    }
-
-    companion object {
-        private val TAG = RawFile::class.java.simpleName
-        private fun getTypeForName(name: String): String {
-            val lastDot = name.lastIndexOf('.')
-            if (lastDot >= 0) {
-                val extension = name.substring(lastDot + 1).lowercase(Locale.getDefault())
-                val mime = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension)
-                if (mime != null) {
-                    return mime
-                }
-            }
-            return "application/octet-stream"
-        }
-
-        private fun deleteContents(dir: File): Boolean {
-            val files = dir.listFiles()
-            var success = true
-            if (files != null) {
-                for (file in files) {
-                    if (file.isDirectory) {
-                        success = success and deleteContents(file)
-                    }
-                    if (!file.delete()) {
-                        Log.w(TAG, "Failed to delete $file")
-                        success = false
-                    }
-                }
-            }
-            return success
-        }
+        return ParcelFileDescriptor.open(mFile, md) ?: throw IOException("Can't open ParcelFileDescriptor")
     }
 }
+
+private fun getTypeForName(name: String): String {
+    val lastDot = name.lastIndexOf('.')
+    if (lastDot >= 0) {
+        val extension = name.substring(lastDot + 1).lowercase(Locale.getDefault())
+        val mime = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension)
+        if (mime != null) {
+            return mime
+        }
+    }
+    return "application/octet-stream"
+}

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

@@ -15,54 +15,51 @@
  */
 package com.hippo.unifile
 
-import android.content.Context
 import android.graphics.ImageDecoder
 import android.net.Uri
+import splitties.init.appCtx
 
-class SingleDocumentFile(parent: UniFile?, context: Context, override val uri: Uri) : UniFile(parent) {
-    private val mContext = context.applicationContext
+class SingleDocumentFile(parent: UniFile?, override val uri: Uri) : UniFile(parent) {
 
     override fun createFile(displayName: String) = null
 
     override fun createDirectory(displayName: String) = null
 
     override val name: String?
-        get() = DocumentsContractApi19.getName(mContext, uri)
+        get() = DocumentsContractApi19.getName(appCtx, uri)
     override val type: String?
-        get() = DocumentsContractApi19.getType(mContext, uri)
+        get() = DocumentsContractApi19.getType(appCtx, uri)
     override val isDirectory: Boolean
-        get() = DocumentsContractApi19.isDirectory(mContext, uri)
+        get() = DocumentsContractApi19.isDirectory(appCtx, uri)
     override val isFile: Boolean
-        get() = DocumentsContractApi19.isFile(mContext, uri)
+        get() = DocumentsContractApi19.isFile(appCtx, uri)
 
-    override fun lastModified() = DocumentsContractApi19.lastModified(mContext, uri)
+    override fun lastModified() = DocumentsContractApi19.lastModified(appCtx, uri)
 
-    override fun length() = DocumentsContractApi19.length(mContext, uri)
+    override fun length() = DocumentsContractApi19.length(appCtx, uri)
 
-    override fun canRead() = DocumentsContractApi19.canRead(mContext, uri)
+    override fun canRead() = DocumentsContractApi19.canRead(appCtx, uri)
 
-    override fun canWrite() = DocumentsContractApi19.canWrite(mContext, uri)
+    override fun canWrite() = DocumentsContractApi19.canWrite(appCtx, uri)
 
     override fun ensureDir() = isDirectory
 
     override fun ensureFile() = isFile
 
-    override fun subFile(displayName: String) = null
+    override fun subFile(displayName: String) = error("SingleDocumentFile never have a children")
 
-    override fun delete() = DocumentsContractApi19.delete(mContext, uri)
+    override fun delete() = DocumentsContractApi19.delete(appCtx, uri)
 
-    override fun exists() = DocumentsContractApi19.exists(mContext, uri)
+    override fun exists() = DocumentsContractApi19.exists(appCtx, uri)
 
-    override fun listFiles() = null
+    override fun listFiles() = emptyList<SingleDocumentFile>()
 
     override fun findFirst(filter: (String) -> Boolean) = null
 
-    override fun findFile(displayName: String) = null
-
     override fun renameTo(displayName: String) = false
 
     override val imageSource: ImageDecoder.Source
-        get() = Contracts.getImageSource(mContext, uri)
+        get() = Contracts.getImageSource(appCtx, uri)
 
-    override fun openFileDescriptor(mode: String) = Contracts.openFileDescriptor(mContext, uri, mode)
+    override fun openFileDescriptor(mode: String) = Contracts.openFileDescriptor(appCtx, uri, mode)
 }

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

@@ -15,44 +15,38 @@
  */
 package com.hippo.unifile
 
-import android.content.Context
 import android.graphics.ImageDecoder
 import android.net.Uri
 import android.os.ParcelFileDescriptor
-import android.util.Log
 import android.webkit.MimeTypeMap
+import eu.kanade.tachiyomi.util.system.logcat
+import splitties.init.appCtx
 
-internal class TreeDocumentFile : UniFile {
-    private val mContext: Context
-    override var uri: Uri
-        private set
-    private var mFilename: String? = null
-
-    constructor(parent: UniFile?, context: Context, uri: Uri) : super(parent) {
-        mContext = context.applicationContext
-        this.uri = uri
+class TreeDocumentFile(
+    parent: UniFile?,
+    override var uri: Uri,
+    val filename: String,
+) : UniFile(parent) {
+    private var cachePresent = false
+    private val allChildren by lazy {
+        cachePresent = true
+        logcat { "Directory lookup cache created for $name" }
+        DocumentsContractApi21.listFiles(appCtx, uri).map {
+            val name = getFilenameForUri(it)
+            TreeDocumentFile(this, it, name)
+        }.toMutableList()
     }
 
-    private constructor(parent: UniFile, context: Context, uri: Uri, filename: String?) : super(
-        parent,
-    ) {
-        mContext = context.applicationContext
-        this.uri = uri
-        mFilename = filename
+    private fun popCacheIfPresent(file: TreeDocumentFile) = apply {
+        if (cachePresent) allChildren.add(file)
     }
 
+    constructor(parent: UniFile?, uri: Uri) : this(parent, uri, getFilenameForUri(uri))
+
     override fun createFile(displayName: String): UniFile? {
         val child = findFile(displayName)
-        return if (child != null) {
-            if (child.isFile) {
-                child
-            } else {
-                Log.w(
-                    TAG,
-                    "Try to create file $displayName, but it is not file",
-                )
-                null
-            }
+        if (child != null) {
+            if (child.isFile) return child
         } else {
             val index = displayName.lastIndexOf('.')
             if (index > 0) {
@@ -60,111 +54,75 @@ internal class TreeDocumentFile : UniFile {
                 val extension = displayName.substring(index + 1)
                 val mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension)
                 if (!mimeType.isNullOrEmpty()) {
-                    val result = DocumentsContractApi21.createFile(mContext, uri, mimeType, name)
-                    return if (result != null) {
-                        TreeDocumentFile(
-                            this,
-                            mContext,
-                            result,
-                            displayName,
-                        )
-                    } else {
-                        null
+                    val result = DocumentsContractApi21.createFile(appCtx, uri, mimeType, name)
+                    if (result != null) {
+                        val f = TreeDocumentFile(this, result, displayName)
+                        popCacheIfPresent(f)
+                        return f
                     }
                 }
-            }
-
-            // Not dot in displayName or dot is the first char or can't get MimeType
-            val result = DocumentsContractApi21.createFile(
-                mContext,
-                uri,
-                "application/octet-stream",
-                displayName,
-            )
-            if (result != null) {
-                TreeDocumentFile(
-                    this,
-                    mContext,
-                    result,
-                    displayName,
-                )
             } else {
-                null
+                // Not dot in displayName or dot is the first char or can't get MimeType
+                val result = DocumentsContractApi21.createFile(appCtx, uri, "application/octet-stream", displayName)
+                if (result != null) {
+                    val f = TreeDocumentFile(this, result, displayName)
+                    popCacheIfPresent(f)
+                    return f
+                }
             }
         }
+        return null
     }
 
     override fun createDirectory(displayName: String): UniFile? {
         val child = findFile(displayName)
-        return if (child != null) {
-            if (child.isDirectory) {
-                child
-            } else {
-                null
-            }
+        if (child != null) {
+            if (child.isDirectory) return null
         } else {
-            val result = DocumentsContractApi21.createDirectory(mContext, uri, displayName)
+            val result = DocumentsContractApi21.createDirectory(appCtx, uri, displayName)
             if (result != null) {
-                TreeDocumentFile(
-                    this,
-                    mContext,
-                    result,
-                    displayName,
-                )
-            } else {
-                null
+                val d = TreeDocumentFile(this, result, displayName)
+                popCacheIfPresent(d)
+                return d
             }
         }
+        return null
     }
 
     override val name: String?
-        get() = DocumentsContractApi19.getName(mContext, uri)
+        get() = DocumentsContractApi19.getName(appCtx, uri)
     override val type: String?
-        get() = DocumentsContractApi19.getType(mContext, uri)
+        get() = DocumentsContractApi19.getType(appCtx, uri)
     override val isDirectory: Boolean
-        get() = DocumentsContractApi19.isDirectory(mContext, uri)
+        get() = DocumentsContractApi19.isDirectory(appCtx, uri)
     override val isFile: Boolean
-        get() = DocumentsContractApi19.isFile(mContext, uri)
+        get() = DocumentsContractApi19.isFile(appCtx, uri)
 
-    override fun lastModified(): Long {
-        return DocumentsContractApi19.lastModified(mContext, uri)
-    }
+    override fun lastModified() = DocumentsContractApi19.lastModified(appCtx, uri)
 
-    override fun length(): Long {
-        return DocumentsContractApi19.length(mContext, uri)
-    }
+    override fun length() = DocumentsContractApi19.length(appCtx, uri)
 
-    override fun canRead(): Boolean {
-        return DocumentsContractApi19.canRead(mContext, uri)
-    }
+    override fun canRead() = DocumentsContractApi19.canRead(appCtx, uri)
 
-    override fun canWrite(): Boolean {
-        return DocumentsContractApi19.canWrite(mContext, uri)
-    }
+    override fun canWrite() = DocumentsContractApi19.canWrite(appCtx, uri)
 
     override fun ensureDir(): Boolean {
-        if (isDirectory) {
-            return true
-        } else if (isFile) {
-            return false
-        }
+        if (isDirectory) return true
+        if (isFile) return false
         val parent = parentFile
-        return if (parent != null && parent.ensureDir() && mFilename != null) {
-            parent.createDirectory(mFilename!!) != null
+        return if (parent != null && parent.ensureDir()) {
+            parent.createDirectory(filename) != null
         } else {
             false
         }
     }
 
     override fun ensureFile(): Boolean {
-        if (isFile) {
-            return true
-        } else if (isDirectory) {
-            return false
-        }
+        if (isFile) return true
+        if (isDirectory) return false
         val parent = parentFile
-        return if (parent != null && parent.ensureDir() && mFilename != null) {
-            parent.createFile(mFilename!!) != null
+        return if (parent != null && parent.ensureDir()) {
+            parent.createFile(filename) != null
         } else {
             false
         }
@@ -172,76 +130,40 @@ internal class TreeDocumentFile : UniFile {
 
     override fun subFile(displayName: String): UniFile {
         val childUri = DocumentsContractApi21.buildChildUri(uri, displayName)
-        return TreeDocumentFile(this, mContext, childUri, displayName)
+        return TreeDocumentFile(this, childUri, displayName)
     }
 
-    override fun delete(): Boolean {
-        return DocumentsContractApi19.delete(mContext, uri)
-    }
+    override fun delete() = DocumentsContractApi19.delete(appCtx, uri)
 
-    override fun exists(): Boolean {
-        return DocumentsContractApi19.exists(mContext, uri)
-    }
+    override fun exists() = DocumentsContractApi19.exists(appCtx, uri)
 
-    private fun getFilenameForUri(uri: Uri): String? {
-        val path = uri.path
-        if (path != null) {
-            val index = path.lastIndexOf('/')
-            if (index >= 0) {
-                return path.substring(index + 1)
-            }
-        }
-        return null
-    }
+    override fun listFiles() = allChildren
 
-    override fun listFiles(): Array<UniFile> {
-        val result = DocumentsContractApi21.listFiles(mContext, uri)
-        return result.map { TreeDocumentFile(this, mContext, it, getFilenameForUri(it)) }.toTypedArray()
-    }
-
-    override fun findFirst(filter: (String) -> Boolean): UniFile? {
-        val result = DocumentsContractApi21.listFiles(mContext, uri)
-        for (uri in result) {
-            val name = getFilenameForUri(uri)
-            if (name != null && filter(name)) {
-                return TreeDocumentFile(this, mContext, uri, name)
-            }
-        }
-        return null
-    }
-
-    override fun findFile(displayName: String): UniFile? {
-        val childUri = DocumentsContractApi21.buildChildUri(uri, displayName)
-        return if (DocumentsContractApi19.exists(mContext, childUri)) {
-            TreeDocumentFile(
-                this,
-                mContext,
-                childUri,
-                displayName,
-            )
-        } else {
-            null
-        }
-    }
+    override fun findFirst(filter: (String) -> Boolean) = allChildren.firstOrNull { filter(it.filename) }
 
     override fun renameTo(displayName: String): Boolean {
-        val result = DocumentsContractApi21.renameTo(mContext, uri, displayName)
-        return if (result != null) {
+        val result = DocumentsContractApi21.renameTo(appCtx, uri, displayName)
+        if (result != null) {
             uri = result
-            true
-        } else {
-            false
+            return true
         }
+        return false
     }
 
     override val imageSource: ImageDecoder.Source
-        get() = Contracts.getImageSource(mContext, uri)
+        get() = Contracts.getImageSource(appCtx, uri)
 
     override fun openFileDescriptor(mode: String): ParcelFileDescriptor {
-        return Contracts.openFileDescriptor(mContext, uri, mode)
+        return Contracts.openFileDescriptor(appCtx, uri, mode)
     }
+}
 
-    companion object {
-        private val TAG = TreeDocumentFile::class.java.simpleName
+private fun getFilenameForUri(uri: Uri): String {
+    val path = requireNotNull(uri.path)
+    val index = path.lastIndexOf('/')
+    return if (index >= 0) {
+        path.substring(index + 1)
+    } else {
+        return path
     }
 }

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

@@ -16,7 +16,6 @@
 package com.hippo.unifile
 
 import android.content.ContentResolver
-import android.content.Context
 import android.content.Intent
 import android.graphics.ImageDecoder
 import android.net.Uri
@@ -24,6 +23,7 @@ import android.os.Build
 import android.os.ParcelFileDescriptor
 import androidx.annotation.RequiresApi
 import java.io.File
+import splitties.init.appCtx
 
 /**
  * In Android files can be accessed via [java.io.File] and [android.net.Uri].
@@ -173,9 +173,9 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
     /**
      * Get child file of this directory, the child might not exist.
      *
-     * @return the child file, `null` if not supported
+     * @return the child file
      */
-    abstract fun subFile(displayName: String): UniFile?
+    abstract fun subFile(displayName: String): UniFile
 
     /**
      * Deletes this file.
@@ -196,14 +196,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
      */
     abstract fun exists(): Boolean
 
-    /**
-     * Returns an array of files contained in the directory represented by this
-     * file.
-     *
-     * @return an array of files or `null`.
-     * @see android.provider.DocumentsContract.buildChildDocumentsUriUsingTree
-     */
-    abstract fun listFiles(): Array<UniFile>?
+    abstract fun listFiles(): List<UniFile>
 
     abstract fun findFirst(filter: (String) -> Boolean): UniFile?
 
@@ -212,7 +205,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
      *
      * @return the file if found it, or `null`.
      */
-    abstract fun findFile(displayName: String): UniFile?
+    fun findFile(displayName: String) = subFile(displayName).takeIf { it.exists() }
 
     /**
      * Renames this file to `displayName`.
@@ -242,36 +235,13 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
     abstract fun openFileDescriptor(mode: String): ParcelFileDescriptor
 
     companion object {
-        private var sUriHandlerArray: MutableList<UriHandler>? = null
-
-        /**
-         * Add a UriHandler to get UniFile from uri
-         */
-        fun addUriHandler(handler: UriHandler) {
-            if (sUriHandlerArray == null) {
-                sUriHandlerArray = ArrayList()
-            }
-            sUriHandlerArray!!.add(handler)
-        }
-
-        /**
-         * Remove the UriHandler added before
-         */
-        fun removeUriHandler(handler: UriHandler) {
-            if (sUriHandlerArray != null) {
-                sUriHandlerArray!!.remove(handler)
-            }
-        }
-
         /**
          * Create a [UniFile] representing the given [File].
          *
          * @param file the file to wrap
          * @return the [UniFile] representing the given [File].
          */
-        fun fromFile(file: File?): UniFile? {
-            return if (file != null) RawFile(null, file) else null
-        }
+        fun fromFile(file: File) = RawFile(null, file)
 
         /**
          * Create a [UniFile] representing the single document at the
@@ -284,14 +254,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
          * [Intent.ACTION_CREATE_DOCUMENT] request.
          * @return the [UniFile] representing the given [Uri].
          */
-        fun fromSingleUri(context: Context, singleUri: Uri): UniFile? {
-            val version = Build.VERSION.SDK_INT
-            return if (version >= 19) {
-                SingleDocumentFile(null, context, singleUri)
-            } else {
-                null
-            }
-        }
+        fun fromSingleUri(singleUri: Uri) = SingleDocumentFile(null, singleUri)
 
         /**
          * Create a [UniFile] representing the document tree rooted at
@@ -303,18 +266,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
          * [Intent.ACTION_OPEN_DOCUMENT_TREE] request.
          * @return the [UniFile] representing the given [Uri].
          */
-        fun fromTreeUri(context: Context, treeUri: Uri): UniFile? {
-            val version = Build.VERSION.SDK_INT
-            return if (version >= 21) {
-                TreeDocumentFile(
-                    null,
-                    context,
-                    DocumentsContractApi21.prepareTreeUri(treeUri),
-                )
-            } else {
-                null
-            }
-        }
+        fun fromTreeUri(treeUri: Uri) = TreeDocumentFile(null, DocumentsContractApi21.prepareTreeUri(treeUri))
 
         /**
          * Create a [UniFile] representing the media file rooted at
@@ -323,36 +275,22 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
          * @param mediaUri the media uri to wrap
          * @return the [UniFile] representing the given [Uri].
          */
-        fun fromMediaUri(context: Context, mediaUri: Uri): UniFile {
-            return MediaFile(context, mediaUri)
-        }
+        fun fromMediaUri(mediaUri: Uri) = MediaFile(mediaUri)
 
         /**
          * Create a [UniFile] representing the given [Uri].
          */
-        fun fromUri(context: Context, uri: Uri): UniFile? {
-            // Custom handler
-            if (sUriHandlerArray != null) {
-                var i = 0
-                val size = sUriHandlerArray!!.size
-                while (i < size) {
-                    val file = sUriHandlerArray!![i].fromUri(context, uri)
-                    if (file != null) {
-                        return file
-                    }
-                    i++
-                }
-            }
+        fun fromUri(uri: Uri): UniFile? {
             return if (isFileUri(uri)) {
                 fromFile(File(uri.path!!))
-            } else if (isDocumentUri(context, uri)) {
+            } else if (isDocumentUri(uri)) {
                 if (isTreeUri(uri)) {
-                    fromTreeUri(context, uri)
+                    fromTreeUri(uri)
                 } else {
-                    fromSingleUri(context, uri)
+                    fromSingleUri(uri)
                 }
-            } else if (MediaFile.isMediaUri(context, uri)) {
-                MediaFile(context, uri)
+            } else if (MediaFile.isMediaUri(uri)) {
+                fromMediaUri(uri)
             } else {
                 null
             }
@@ -369,14 +307,7 @@ abstract class UniFile internal constructor(private val parent: UniFile?) {
          * Test if given Uri is backed by a
          * [android.provider.DocumentsProvider].
          */
-        fun isDocumentUri(context: Context, uri: Uri): Boolean {
-            val version = Build.VERSION.SDK_INT
-            return if (version >= 19) {
-                DocumentsContractApi19.isDocumentUri(context, uri)
-            } else {
-                false
-            }
-        }
+        fun isDocumentUri(uri: Uri) = DocumentsContractApi19.isDocumentUri(appCtx, uri)
 
         /**
          * Test if given Uri is TreeUri

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

@@ -1,9 +1,12 @@
 package com.hippo.unifile
 
+import android.net.Uri
 import android.os.ParcelFileDescriptor.AutoCloseInputStream
 import android.os.ParcelFileDescriptor.AutoCloseOutputStream
+import java.io.File
 import java.io.FileInputStream
 import java.io.FileOutputStream
+import okio.Path
 
 /**
  * Use Native IO/NIO directly if possible, unless you need process file content on JVM!
@@ -18,3 +21,11 @@ fun UniFile.openInputStream(): FileInputStream {
 fun UniFile.openOutputStream(): FileOutputStream {
     return AutoCloseOutputStream(openFileDescriptor("w"))
 }
+
+fun File.asUniFile() = UniFile.fromFile(this)
+
+fun Path.asUniFile() = toFile().asUniFile()
+
+fun Uri.asUniFileOrNull() = UniFile.fromUri(this)
+
+fun Uri.asUniFile() = requireNotNull(asUniFileOrNull())

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

@@ -1,32 +0,0 @@
-/*
- * Copyright 2016 Hippo Seven
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.hippo.unifile
-
-import android.content.Context
-import android.net.Uri
-
-/*
- * Created by Hippo on 8/16/2016.
- */
-/**
- * A UriHandler is to get UniFile from custom uri for extensions
- */
-interface UriHandler {
-    /**
-     * Create a [UniFile] representing the uri
-     */
-    fun fromUri(context: Context?, uri: Uri?): UniFile?
-}

app/src/main/kotlin/eu/kanade/tachiyomi/ui/reader/ReaderActivity.kt

@@ -96,7 +96,7 @@ import com.hippo.ehviewer.util.lazyMut
 import com.hippo.ehviewer.util.requestPermission
 import com.hippo.ehviewer.util.sendTo
 import com.hippo.ehviewer.util.setValue
-import com.hippo.unifile.UniFile
+import com.hippo.unifile.asUniFile
 import dev.chrisbanes.insetter.applyInsetter
 import eu.kanade.tachiyomi.ui.reader.model.ReaderPage
 import eu.kanade.tachiyomi.ui.reader.setting.OrientationType
@@ -408,7 +408,7 @@ class ReaderActivity : EhActivity() {
         }
         val file = mGalleryProvider!!.save(
             page,
-            UniFile.fromFile(dir)!!,
+            dir.asUniFile(),
             mGalleryProvider!!.getImageFilenameWithExtension(page),
         )
         if (file == null) {
@@ -466,7 +466,7 @@ class ReaderActivity : EhActivity() {
         }
         val file = mGalleryProvider!!.save(
             page,
-            UniFile.fromFile(dir)!!,
+            dir.asUniFile(),
             mGalleryProvider!!.getImageFilenameWithExtension(page),
         )
         if (file == null) {
@@ -534,7 +534,7 @@ class ReaderActivity : EhActivity() {
                     Toast.makeText(this@ReaderActivity, R.string.error_cant_save_image, Toast.LENGTH_SHORT).show()
                     return@launchUI
                 }
-                if (!mGalleryProvider!!.save(page, UniFile.fromMediaUri(this@ReaderActivity, imageUri))) {
+                if (!mGalleryProvider!!.save(page, imageUri.asUniFile())) {
                     try {
                         resolver.delete(imageUri, null, null)
                     } catch (e: Exception) {
@@ -571,7 +571,7 @@ class ReaderActivity : EhActivity() {
         }
         val file = mGalleryProvider!!.save(
             page,
-            UniFile.fromFile(dir)!!,
+            dir.asUniFile(),
             mGalleryProvider!!.getImageFilenameWithExtension(page),
         )
         if (file == null) {