add a couple things related to file copying

app/src/main/kotlin/com/simplemobiletools/gallery/activities/PickAlbumActivity.kt

@@ -7,6 +7,7 @@ import com.simplemobiletools.gallery.R
 import com.simplemobiletools.gallery.Utils
 import com.simplemobiletools.gallery.adapters.DirectoryAdapter
 import com.simplemobiletools.gallery.asynctasks.GetDirectoriesAsynctask
+import com.simplemobiletools.gallery.extensions.toast
 import com.simplemobiletools.gallery.models.Directory
 import kotlinx.android.synthetic.main.activity_main.*
 import java.util.*
@@ -27,7 +28,7 @@ class PickAlbumActivity : SimpleActivity(), AdapterView.OnItemClickListener, Get
         if (Utils.hasStoragePermission(applicationContext)) {
             getDirectories()
         } else {
-            Utils.showToast(applicationContext, R.string.no_permissions)
+            toast(R.string.no_permissions)
         }
     }
 

app/src/main/kotlin/com/simplemobiletools/gallery/asynctasks/CopyTask.kt

@@ -0,0 +1,119 @@
+package com.simplemobiletools.gallery.asynctasks
+
+import android.content.Context
+import android.os.AsyncTask
+import android.support.v4.util.Pair
+import android.util.Log
+import com.simplemobiletools.gallery.Utils
+import java.io.*
+import java.lang.ref.WeakReference
+
+class CopyTask(listener: CopyTask.CopyListener, val context: Context) : AsyncTask<Pair<List<File>, File>, Void, Boolean>() {
+    private val TAG = CopyTask::class.java.simpleName
+    private var mListener: WeakReference<CopyListener>? = null
+    private var destinationDir: File? = null
+
+    init {
+        mListener = WeakReference(listener)
+    }
+
+    override fun doInBackground(vararg params: Pair<List<File>, File>): Boolean? {
+        val pair = params[0]
+        val files = pair.first
+        for (file in files) {
+            try {
+                destinationDir = File(pair.second, file.name)
+                copy(file, destinationDir!!)
+            } catch (e: Exception) {
+                Log.e(TAG, "copy " + e)
+                return false
+            }
+        }
+        return true
+    }
+
+    @Throws(Exception::class)
+    private fun copy(source: File, destination: File) {
+        if (source.isDirectory) {
+            copyDirectory(source, destination)
+        } else {
+            copyFile(source, destination)
+        }
+    }
+
+    private fun copyDirectory(source: File, destination: File) {
+        if (!destination.exists()) {
+            if (Utils.needsStupidWritePermissions(context, destination.absolutePath)) {
+                val document = Utils.getFileDocument(context, destination.absolutePath)
+                document.createDirectory(destination.name)
+            } else if (!destination.mkdirs()) {
+                throw IOException("Could not create dir " + destination.absolutePath)
+            }
+        }
+
+        val children = source.list()
+        for (child in children) {
+            val newFile = File(source, child)
+            if (Utils.needsStupidWritePermissions(context, destination.absolutePath)) {
+                if (newFile.isDirectory) {
+                    copyDirectory(newFile, File(destination, child))
+                } else {
+                    var document = Utils.getFileDocument(context, destination.absolutePath)
+                    document = document.createFile("", child)
+
+                    val inputStream = FileInputStream(newFile)
+                    val out = context.contentResolver.openOutputStream(document.uri)
+                    copyStream(inputStream, out)
+                }
+            } else {
+                copy(newFile, File(destination, child))
+            }
+        }
+    }
+
+    private fun copyFile(source: File, destination: File) {
+        val directory = destination.parentFile
+        if (!directory.exists() && !directory.mkdirs()) {
+            throw IOException("Could not create dir " + directory.absolutePath)
+        }
+
+        val inputStream = FileInputStream(source)
+        val out: OutputStream?
+        if (Utils.needsStupidWritePermissions(context, destination.absolutePath)) {
+            var document = Utils.getFileDocument(context, destination.absolutePath)
+            document = document.createFile("", destination.name)
+            out = context.contentResolver.openOutputStream(document.uri)
+        } else {
+            out = FileOutputStream(destination)
+        }
+
+        copyStream(inputStream, out)
+    }
+
+    private fun copyStream(inputStream: InputStream, out: OutputStream?) {
+        val buf = ByteArray(1024)
+        var len: Int
+        while (true) {
+            len = inputStream.read(buf)
+            if (len <= 0)
+                break
+            out?.write(buf, 0, len)
+        }
+    }
+
+    override fun onPostExecute(success: Boolean) {
+        val listener = mListener?.get() ?: return
+
+        if (success) {
+            listener.copySucceeded(destinationDir!!)
+        } else {
+            listener.copyFailed()
+        }
+    }
+
+    interface CopyListener {
+        fun copySucceeded(destinationDir: File)
+
+        fun copyFailed()
+    }
+}

app/src/main/kotlin/com/simplemobiletools/gallery/dialogs/CopyDialog.kt

@@ -0,0 +1,98 @@
+package com.simplemobiletools.gallery.dialogs
+
+import android.app.Activity
+import android.support.v4.util.Pair
+import android.support.v7.app.AlertDialog
+import android.view.LayoutInflater
+import android.view.WindowManager
+import com.simplemobiletools.gallery.R
+import com.simplemobiletools.gallery.Utils
+import com.simplemobiletools.gallery.asynctasks.CopyTask
+import com.simplemobiletools.gallery.extensions.scanFile
+import com.simplemobiletools.gallery.extensions.toast
+import com.simplemobiletools.gallery.extensions.value
+import kotlinx.android.synthetic.main.copy_item.view.*
+import java.io.File
+import java.util.*
+
+class CopyDialog(val activity: Activity, val files: List<File>, val path: String, val copyListener: CopyTask.CopyListener, val listener: OnCopyListener) {
+
+    init {
+        val context = activity
+        val view = LayoutInflater.from(context).inflate(R.layout.copy_item, null)
+        view.source.text = "${path.trimEnd('/')}/"
+
+        view.destination.setOnClickListener {
+
+        }
+
+        AlertDialog.Builder(context)
+                .setTitle(context.resources.getString(if (files.size == 1) R.string.copy_item else R.string.copy_items))
+                .setView(view)
+                .setPositiveButton(R.string.ok, null)
+                .setNegativeButton(R.string.cancel, null)
+                .create().apply {
+            window!!.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE)
+            show()
+            getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener({
+                val destinationPath = view.destination.value
+                if (destinationPath == context.resources.getString(R.string.select_destination)) {
+                    context.toast(R.string.please_select_destination)
+                    return@setOnClickListener
+                }
+
+                if (view.source.text.trimEnd('/') == destinationPath.trimEnd('/')) {
+                    context.toast(R.string.source_and_destination_same)
+                    return@setOnClickListener
+                }
+
+                val destinationDir = File(destinationPath)
+                if (!destinationDir.exists()) {
+                    context.toast(R.string.invalid_destination)
+                    return@setOnClickListener
+                }
+
+                if (files.size == 1) {
+                    val newFile = File(files[0].path)
+                    if (File(destinationPath, newFile.name).exists()) {
+                        context.toast(R.string.already_exists)
+                        return@setOnClickListener
+                    }
+                }
+
+                if (Utils.isShowingWritePermissions(context, destinationDir)) {
+                    return@setOnClickListener
+                }
+
+                if (view.dialog_radio_group.checkedRadioButtonId == R.id.dialog_radio_copy) {
+                    context.toast(R.string.copying)
+                    val pair = Pair<List<File>, File>(files, destinationDir)
+                    CopyTask(copyListener, context).execute(pair)
+                    dismiss()
+                } else {
+                    if (Utils.isPathOnSD(context, view.source.value) && Utils.isPathOnSD(context, destinationPath)) {
+                        val paths = ArrayList<String>()
+                        for (f in files) {
+                            val destination = File(destinationDir, f.name)
+                            f.renameTo(destination)
+                            paths.add(destination.absolutePath)
+                        }
+
+                        context.scanFile(paths.toTypedArray())
+
+                        dismiss()
+                        listener.onSuccess()
+                    } else {
+                        val pair = Pair<List<File>, File>(files, destinationDir)
+                        CopyTask(copyListener, context).execute(pair)
+                        dismiss()
+                    }
+                }
+            })
+        }
+    }
+
+    interface OnCopyListener {
+        fun onSuccess()
+    }
+}

app/src/main/kotlin/com/simplemobiletools/gallery/extensions/context.kt

@@ -1,8 +1,11 @@
 package com.simplemobiletools.gallery.extensions
 
 import android.content.Context
+import android.media.MediaScannerConnection
 import android.widget.Toast
 
 fun Context.toast(msg: String, duration: Int = Toast.LENGTH_SHORT) = Toast.makeText(this, msg, duration).show()
 
 fun Context.toast(msgId: Int, duration: Int = Toast.LENGTH_SHORT) = Toast.makeText(this, resources.getString(msgId), duration).show()
+
+fun Context.scanFile(paths: Array<String>) = MediaScannerConnection.scanFile(this, paths, null, null)

app/src/main/kotlin/com/simplemobiletools/gallery/extensions/textView.kt

@@ -0,0 +1,5 @@
+package com.simplemobiletools.gallery.extensions
+
+import android.widget.TextView
+
+val TextView.value: String get() = this.text.toString().trim()