Copy with SAF

import android.net.Uri;
import android.provider.DocumentsContract;
import android.database.Cursor;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.util.regex.Pattern;
import org.json.JSONArray;
import org.json.JSONObject;

// === Inputs ===
String treeStr   = "%uri_tree";   // SAF source tree
String targetStr = "%target";     // must be /storage/... filesystem path
String pattern   = "%pattern";    // e.g. /databases/*.db

// --- Extract subPath + file pattern ---
String subPath = "";
String filePattern = pattern;

int slashIdx = pattern.lastIndexOf("/");
if (slashIdx != -1) {
    subPath = pattern.substring(0, slashIdx);       // e.g. "/databases"
    filePattern = pattern.substring(slashIdx + 1);  // e.g. "*.db"
    if (subPath.startsWith("/")) subPath = subPath.substring(1);
}

// Convert wildcard → regex
String regex = filePattern.replace(".", "\\.").replace("*", ".*").replace("?", ".");
Pattern p = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);

// --- Setup source tree ---
Uri treeUri = Uri.parse(treeStr);
String rootDocId = DocumentsContract.getTreeDocumentId(treeUri);
Uri currentChildren = DocumentsContract.buildChildDocumentsUriUsingTree(treeUri, rootDocId);

// Walk into subPath if provided
if (!subPath.isEmpty()) {
    String[] parts = subPath.split("/");
    for (String part : parts) {
        Cursor c = context.getContentResolver().query(
            currentChildren,
            new String[] {
                DocumentsContract.Document.COLUMN_DOCUMENT_ID,
                DocumentsContract.Document.COLUMN_DISPLAY_NAME,
                DocumentsContract.Document.COLUMN_MIME_TYPE
            },
            null, null, null);

        boolean found = false;
        if (c != null) {
            while (c.moveToNext()) {
                String childId = c.getString(0);
                String name    = c.getString(1);
                String mime    = c.getString(2);

                if (name != null && name.equals(part) &&
                    DocumentsContract.Document.MIME_TYPE_DIR.equals(mime)) {
                    currentChildren = DocumentsContract.buildChildDocumentsUriUsingTree(treeUri, childId);
                    found = true;
                    break;
                }
            }
            c.close();
        }
        if (!found) {
            throw new IllegalArgumentException("Subfolder not found: " + part);
        }
    }
}

// --- Prepare JSON result ---
JSONArray result = new JSONArray();

// --- Query + match files ---
Cursor cursor = context.getContentResolver().query(
    currentChildren,
    new String[] {
        DocumentsContract.Document.COLUMN_DOCUMENT_ID,
        DocumentsContract.Document.COLUMN_DISPLAY_NAME
    },
    null, null, null);

if (cursor != null) {
    while (cursor.moveToNext()) {
        String childId = cursor.getString(0);
        String name    = cursor.getString(1);

        if (name != null && p.matcher(name).matches()) {
            JSONObject item = new JSONObject();
            item.put("name", name);
            item.put("status", "matched");

            try {
                // Source stream
                Uri srcDocUri = DocumentsContract.buildDocumentUriUsingTree(treeUri, childId);
                InputStream in = context.getContentResolver().openInputStream(srcDocUri);

                // Destination: filesystem file
                File destFile = new File(targetStr, name);
                if (destFile.exists()) destFile.delete(); // overwrite
                OutputStream out = new FileOutputStream(destFile);

                byte[] buffer = new byte[8192];
                int len;
                while ((len = in.read(buffer)) != -1) {
                    out.write(buffer, 0, len);
                }

                in.close();
                out.close();

                item.put("copied", true);
                item.put("targetPath", destFile.getAbsolutePath());
            } catch (Exception e) {
                item.put("copied", false);
                item.put("error", e.toString());
            }

            result.put(item);
        }
    }
    cursor.close();
}

return result.toString();