android: Use ContentResolver to get file extension

Fixes an issue where we try to resolve file extension from URIs. Sometimes the URI will not contain the file name at all and instead a string of numbers. Here we query the content resolver and guarantee that we get a file name every time.

src/android/app/src/main/java/org/yuzu/yuzu_emu/ui/main/MainActivity.kt

@@ -284,10 +284,10 @@ class MainActivity : AppCompatActivity(), ThemeProvider {
             if (result == null)
                 return@registerForActivityResult
 
-            if (!FileUtil.hasExtension(result.toString(), "keys")) {
+            if (!FileUtil.hasExtension(result, "keys")) {
                 MessageDialogFragment.newInstance(
                     R.string.reading_keys_failure,
-                    R.string.install_keys_failure_extension_description
+                    R.string.install_prod_keys_failure_extension_description
                 ).show(supportFragmentManager, MessageDialogFragment.TAG)
                 return@registerForActivityResult
             }
@@ -379,10 +379,10 @@ class MainActivity : AppCompatActivity(), ThemeProvider {
             if (result == null)
                 return@registerForActivityResult
 
-            if (!FileUtil.hasExtension(result.toString(), "bin")) {
+            if (!FileUtil.hasExtension(result, "bin")) {
                 MessageDialogFragment.newInstance(
                     R.string.reading_keys_failure,
-                    R.string.install_keys_failure_extension_description
+                    R.string.install_amiibo_keys_failure_extension_description
                 ).show(supportFragmentManager, MessageDialogFragment.TAG)
                 return@registerForActivityResult
             }

src/android/app/src/main/java/org/yuzu/yuzu_emu/utils/FileUtil.kt

@@ -7,7 +7,9 @@ import android.content.Context
 import android.database.Cursor
 import android.net.Uri
 import android.provider.DocumentsContract
+import android.provider.OpenableColumns
 import androidx.documentfile.provider.DocumentFile
+import org.yuzu.yuzu_emu.YuzuApplication
 import org.yuzu.yuzu_emu.model.MinimalDocumentFile
 import java.io.BufferedInputStream
 import java.io.File
@@ -324,7 +326,25 @@ object FileUtil {
         }
     }
 
-    fun hasExtension(path: String, extension: String): Boolean {
-        return path.substring(path.lastIndexOf(".") + 1).contains(extension)
+    fun hasExtension(path: String, extension: String): Boolean =
+        path.substring(path.lastIndexOf(".") + 1).contains(extension)
+
+    fun hasExtension(uri: Uri, extension: String): Boolean {
+        val fileName: String?
+        val cursor = YuzuApplication.appContext.contentResolver.query(uri, null, null, null, null)
+        val nameIndex = cursor?.getColumnIndex(OpenableColumns.DISPLAY_NAME)
+        cursor?.moveToFirst()
+
+        if (nameIndex == null) {
+            return false
+        }
+
+        fileName = cursor.getString(nameIndex)
+        cursor.close()
+
+        if (fileName == null) {
+            return false
+        }
+        return fileName.substring(fileName.lastIndexOf(".") + 1).contains(extension)
     }
 }

src/android/app/src/main/res/values/strings.xml

@@ -65,11 +65,8 @@
     <string name="invalid_keys_file">Invalid keys file selected</string>
     <string name="install_keys_success">Keys successfully installed</string>
     <string name="reading_keys_failure">Error reading encryption keys</string>
-    <string name="install_keys_failure_extension_description">
-        1. Verify your keys have the .keys extension.\n\n
-        2. Keys must not be stored in the Downloads folder.\n\n
-        Resolve the issue(s) and try again.
-    </string>
+    <string name="install_prod_keys_failure_extension_description">Verify your keys file has a .keys extension and try again.</string>
+    <string name="install_amiibo_keys_failure_extension_description">Verify your keys file has a .bin extension and try again.</string>
     <string name="invalid_keys_error">Invalid encryption keys</string>
     <string name="dumping_keys_quickstart_link">https://yuzu-emu.org/help/quickstart/#dumping-decryption-keys</string>
     <string name="install_keys_failure_description">The selected file is incorrect or corrupt. Please redump your keys.</string>