noesis_runtime 0.12.1

// VisualStateManager FFI.
//
// A thin entrypoint over `VisualStateManager::GoToState` so Rust can drive
// control state transitions (the CommonStates / CheckStates / FocusStates
// groups a ControlTemplate declares) from code instead of only through triggers.
//
// The SDK signature is:
//
//     static bool VisualStateManager::GoToState(
//         FrameworkElement* control, Symbol stateName, bool useTransitions);
//
// The parameter is a `FrameworkElement*`, but GoToState only does useful work
// for a templated control: it walks the element's ControlTemplate looking for
// the VisualStateGroup that owns `stateName`. A plain element with no template
// (a bare Grid, a TextBlock) has no state groups to find, so the call returns
// false. So we don't gate on "is a Control" ourselves: an unknown state name
// and a non-templated element both fall out as `false`, which is the contract
// we want. (We expose GoToState rather than GoToElementState because control
// state transitions are the common case; GoToElementState is for app-defined
// groups on an arbitrary root and can be added separately if a need shows up.)
//
// No VerifyAccess(): this must never throw across the C ABI (mirrors the
// text_get/set and dependency_object_* accessors). Single-thread (View) affinity
// is the caller's responsibility.

#include "noesis_shim.h"

#include <NsCore/Noesis.h>
#include <NsCore/DynamicCast.h>
#include <NsCore/Symbol.h>
#include <NsGui/FrameworkElement.h>
#include <NsGui/VisualStateManager.h>

extern "C" bool noesis_visual_state_go_to_state(
    void* element,
    const char* state,
    bool use_transitions) {
    if (!element || !state) return false;
    auto* base = static_cast<Noesis::BaseComponent*>(element);
    auto* fe = Noesis::DynamicCast<Noesis::FrameworkElement*>(base);
    if (!fe) return false;
    return Noesis::VisualStateManager::GoToState(fe, Noesis::Symbol(state), use_transitions);
}