add file save dialog on win

src/app.h

@@ -159,6 +159,7 @@ public:
     bool clipboard_set_text(const std::string& s);
     void pick_image(std::function<void(std::string path)> callback);
     void pick_file(std::vector<std::string> types, std::function<void(std::string path)> callback);
+    void pick_file_save(std::vector<std::string> types, std::function<void(std::string path)> callback);
     void pick_dir(std::function<void(std::string path)> callback);
     void display_file(std::string path);
     void share_file(std::string path);

src/app_events.cpp

@@ -8,6 +8,7 @@ std::string android_get_clipboard();
 bool android_set_clipboard(const std::string& s);
 #elif _WIN32
 std::string win32_open_file(const char* filter);
+std::string win32_save_file(const char* filter);
 std::string win32_open_dir();
 void win32_show_cursor(bool visible);
 bool win32_clipboard_set_text(const std::string & s);
@@ -193,6 +194,50 @@ void App::pick_file(std::vector<std::string> types, std::function<void (std::str
 #endif
 }
 
+void App::pick_file_save(std::vector<std::string> types, std::function<void (std::string)> callback)
+{
+    redraw = true;
+#ifdef __IOS__
+    // not implemented on ios
+    // fallback to pick_image
+    //dispatch_async(dispatch_get_main_queue(), ^{
+    //    [ios_view pick_photo:callback];
+    //});
+#elif __OSX__
+    //dispatch_async(dispatch_get_main_queue(), ^{
+    //    //NSArray* fileTypes = [NSArray arrayWithObjects:@"ppi", @"PPI", nil];
+    //    NSMutableArray<NSString*>* fileTypes = [NSMutableArray arrayWithCapacity:types.size()];
+    //    for (const auto& t : types)
+    //        [fileTypes addObject:[NSString stringWithCString:t.c_str() encoding:NSUTF8StringEncoding]];
+    //    std::string path = [osx_view pick_file:fileTypes];
+    //    if (!path.empty())
+    //        callback(path);
+    //});
+#elif __ANDROID__
+    //android_pick_file(callback);
+#elif _WIN32
+    std::string filter = "Supported Files (";
+    bool first_type = true;
+    for (auto& t : types)
+    {
+        filter.append(std::string(first_type ? "" : " ,") + "*." + t);
+        first_type = false;
+    }
+    filter.append(")");
+    filter.push_back(0);
+    first_type = true;
+    for (auto& t : types)
+    {
+        filter.append(std::string(first_type ? "" : ";") + "*." + t);
+        first_type = false;
+    }
+    filter.push_back(0);
+    std::string path = win32_save_file(filter.c_str());
+    if (!path.empty())
+        callback(path);
+#endif
+}
+
 void App::pick_dir(std::function<void(std::string path)> callback)
 {
     redraw = true;

src/main.cpp

@@ -278,6 +278,26 @@ std::string win32_open_file(const char* filter)
     return "";
 }
 
+std::string win32_save_file(const char* filter)
+{
+    OPENFILENAMEA ofn;
+    char fileName[MAX_PATH] = "";
+    ZeroMemory(&ofn, sizeof(ofn));
+    ofn.lStructSize = sizeof(OPENFILENAME);
+    ofn.hwndOwner = hWnd;
+    ofn.lpstrFilter = filter;
+    ofn.lpstrFile = fileName;
+    ofn.nMaxFile = MAX_PATH;
+    ofn.Flags = OFN_EXPLORER | OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_NOCHANGEDIR;
+    ofn.lpstrDefExt = "";
+    ofn.lpstrInitialDir = "";
+    if (GetSaveFileNameA(&ofn) != NULL)
+    {
+        return fileName;
+    }
+    return "";
+}
+
 std::string win32_open_dir()
 {
     BROWSEINFOA bi;