[Android] Properly get the basename of files

Use the ContentResolver API to get the display name for content: URIs.

Remaining TODO: Add refreshing to other uses of Emu.basename as well.

core/os/os-android.cpp

@@ -2,15 +2,23 @@
 #include <QAndroidJniObject>
 #include <QAndroidJniEnvironment>
 #include <QAndroidActivityResultReceiver>
+#include <QDebug>
+#include <QScopeGuard>
+#include <QUrl>
 
 #include "os.h"
 
+static bool is_content_url(const char *path)
+{
+    const char pattern[] = "content:";
+    return strncmp(pattern, path, sizeof(pattern) - 1) == 0;
+}
+
 // A handler to open android content:// URLs.
 // Based on code by Florin9doi: https://github.com/nspire-emus/firebird/pull/94/files
 FILE *fopen_utf8(const char *path, const char *mode)
 {
-    const char pattern[] = "content:";
-    if(strncmp(pattern, path, sizeof(pattern)-1) != 0)
+    if(!is_content_url(path))
         return fopen(path, mode);
 
     QString android_mode; // Why did they have to NIH...
@@ -78,3 +86,72 @@ FILE *fopen_utf8(const char *path, const char *mode)
 
     return fdopen(fd, mode);
 }
+
+static QString android_basename_using_content_resolver(const QString &path)
+{
+    QAndroidJniObject jpath = QAndroidJniObject::fromString(path);
+    QAndroidJniObject uri = QAndroidJniObject::callStaticObjectMethod(
+                "android/net/Uri", "parse", "(Ljava/lang/String;)Landroid/net/Uri;",
+                jpath.object<jstring>());
+
+    QAndroidJniObject contentResolver = QtAndroid::androidActivity()
+            .callObjectMethod("getContentResolver",
+                              "()Landroid/content/ContentResolver;");
+
+    QAndroidJniEnvironment env;
+    QAndroidJniObject col = QAndroidJniObject::getStaticObjectField("android/provider/OpenableColumns", "DISPLAY_NAME", "Ljava/lang/String;");
+    QAndroidJniObject proj = env->NewObjectArray(1, env->FindClass("java/lang/String"), col.object<jstring>());
+
+    QAndroidJniObject cursor = contentResolver.callObjectMethod("query", "(Landroid/net/Uri;[Ljava/lang/String;Landroid/os/Bundle;Landroid/os/CancellationSignal;)Landroid/database/Cursor;", uri.object<jobject>(), proj.object<jobject>(), nullptr, nullptr);
+    if (env->ExceptionCheck())
+    {
+        env->ExceptionDescribe();
+        env->ExceptionClear();
+        return {};
+    }
+
+    if(!cursor.isValid())
+        return {};
+
+    auto closeCursor = qScopeGuard([&] { cursor.callMethod<void>("close", "()V"); });
+
+    bool hasContent = cursor.callMethod<jboolean>("moveToFirst", "()Z");
+    if (env->ExceptionCheck())
+    {
+        env->ExceptionDescribe();
+        env->ExceptionClear();
+        return {};
+    }
+
+    if(!hasContent)
+        return {};
+
+    QAndroidJniObject name = cursor.callObjectMethod("getString", "(I)Ljava/lang/String;", 0);
+    if (!name.isValid())
+        return {};
+
+    return name.toString();
+}
+
+char *android_basename(const char *path)
+{
+    if (is_content_url(path))
+    {
+        // Example: content://com.android.externalstorage.documents/document/primary%3AFirebird%2Fflash_tpad
+        QString pathStr = QString::fromUtf8(path);
+        QString ret = android_basename_using_content_resolver(pathStr);
+        // If that failed (e.g. because the permission expired), try to get something recognizable.
+        if (ret.isEmpty())
+        {
+            qWarning() << "Failed to get basename of" << pathStr << "using ContentResolver";
+            auto parts = pathStr.splitRef(QStringLiteral("%2F"), QString::SkipEmptyParts, Qt::CaseInsensitive);
+            if(parts.length() > 1)
+                ret = QUrl::fromPercentEncoding(parts.last().toString().toUtf8());
+        }
+
+        if (!ret.isEmpty())
+            return strdup(ret.toUtf8().data());
+    }
+
+    return nullptr;
+}

core/os/os.h

@@ -22,6 +22,11 @@ int iOS_is_debugger_attached();
 /* Some really crappy APIs don't use UTF-8 in fopen. */
 FILE *fopen_utf8(const char *filename, const char *mode);
 
+#if defined(__ANDROID__)
+/* Returns an allocated string or NULL on failure. */
+char *android_basename(const char *path);
+#endif
+
 void *os_reserve(size_t size);
 void *os_alloc_executable(size_t size);
 void os_free(void *ptr, size_t size);

qml/Firebird/UIComponents/FileSelect.qml

@@ -45,7 +45,7 @@ RowLayout {
             Layout.preferredWidth: 100
 
             font.italic: filePath === ""
-            text: filePath === "" ? qsTr("(none)") : Emu.basename(filePath)
+            text: { forceRefresh; return filePath === "" ? qsTr("(none)") : Emu.basename(filePath); }
             color: { forceRefresh; return ((!selectExisting && Emu.saveDialogSupported()) || filePath === "" || Emu.fileExists(filePath)) ? paletteActive.text : "red"; }
         }
 

qmlbridge.cpp

@@ -294,14 +294,11 @@ QString QMLBridge::basename(QString path)
     if(path.isEmpty())
         return tr("None");
 
-    if(path.startsWith(QStringLiteral("content://")))
-    {
-        auto parts = path.splitRef(QStringLiteral("%2F"), QString::SkipEmptyParts, Qt::CaseInsensitive);
-        if(parts.length() > 1)
-            return parts.last().toString();
-
-        return tr("(Android File)");
-    }
+#ifdef Q_OS_ANDROID
+    QScopedPointer<char, QScopedPointerPodDeleter> android_bn{android_basename(path.toUtf8().data())};
+    if(android_bn)
+        return QString::fromUtf8(android_bn.data());
+#endif
 
     return QFileInfo(path).fileName();
 }