fix(share_plus): reset stale share state and normalize path separators on Windows

packages/share_plus/share_plus/windows/share_plus_plugin.cpp

@@ -1,5 +1,6 @@
 #include "share_plus_windows_plugin.h"
 
+#include <algorithm>
 #include <flutter/method_channel.h>
 #include <flutter/plugin_registrar_windows.h>
 #include <flutter/standard_method_codec.h>
@@ -57,6 +58,11 @@ SharePlusWindowsPlugin::GetDataTransferManager() {
 HRESULT SharePlusWindowsPlugin::GetStorageFileFromPath(
     wchar_t *path, WindowsStorage::IStorageFile **file) {
   using Microsoft::WRL::Wrappers::HStringReference;
+
+  // Normalize path separators: WinRT GetFileFromPathAsync requires backslashes ('\').
+  std::wstring normalized_path(path);
+  std::replace(normalized_path.begin(), normalized_path.end(), L'/', L'\\');
+
   WRL::ComPtr<WindowsStorage::IStorageFileStatics> factory = nullptr;
   HRESULT hr = S_OK;
   *file = nullptr;
@@ -69,8 +75,8 @@ HRESULT SharePlusWindowsPlugin::GetStorageFileFromPath(
     WRL::ComPtr<
         WindowsFoundation::IAsyncOperation<WindowsStorage::StorageFile *>>
         async_operation;
-    hr = factory->GetFileFromPathAsync(HStringReference(path).Get(),
-                                       &async_operation);
+    hr = factory->GetFileFromPathAsync(
+        HStringReference(normalized_path.c_str()).Get(), &async_operation);
     if (SUCCEEDED(hr)) {
       WRL::ComPtr<IAsyncInfo> info;
       hr = async_operation.As(&info);
@@ -98,6 +104,14 @@ void SharePlusWindowsPlugin::HandleMethodCall(
     auto data_transfer_manager = GetDataTransferManager();
     auto args = std::get<flutter::EncodableMap>(*method_call.arguments());
 
+    // Reset all share parameters from previous invocations to prevent state leaks.
+    share_text_.reset();
+    share_subject_.reset();
+    share_uri_.reset();
+    share_title_.reset();
+    paths_.clear();
+    mime_types_.clear();
+
     // Extract the text, subject, uri, title, paths and mimeTypes from the arguments
     if (auto text_value = std::get_if<std::string>(
             &args[flutter::EncodableValue("text")])) {
@@ -144,8 +158,8 @@ void SharePlusWindowsPlugin::HandleMethodCall(
           data->get_Properties(&properties);
 
           // Set the title of the share dialog
-          // Prefer the title, then the subject, then the text
-          // Setting a title is mandatory for Windows
+          // Prefer the title, then the subject, then the text, then the first file's name
+          // Setting a non-empty title is mandatory for Windows
           if (share_title_ && !share_title_.value_or("").empty()) {
             auto title = Utf16FromUtf8(share_title_.value_or(""));
             properties->put_Title(HStringReference(title.c_str()).Get());
@@ -154,6 +168,20 @@ void SharePlusWindowsPlugin::HandleMethodCall(
             auto title = Utf16FromUtf8(share_subject_.value_or(""));
             properties->put_Title(HStringReference(title.c_str()).Get());
           }
+          else if (share_text_ && !share_text_.value_or("").empty()) {
+            auto title = Utf16FromUtf8(share_text_.value_or(""));
+            properties->put_Title(HStringReference(title.c_str()).Get());
+          }
+          else if (!paths_.empty()) {
+            // Fallback to the first file's name if no title, subject, or text was provided
+            const std::string& first_path = paths_.front();
+            auto last_slash = first_path.find_last_of("/\\");
+            std::string file_name = (last_slash != std::string::npos)
+                ? first_path.substr(last_slash + 1)
+                : first_path;
+            auto title = Utf16FromUtf8(file_name);
+            properties->put_Title(HStringReference(title.c_str()).Get());
+          }
           else {
             auto title = Utf16FromUtf8(share_text_.value_or(""));
             properties->put_Title(HStringReference(title.c_str()).Get());