SonicForgeStudio/native_bridge/juce_fx/JuceFxGuiHost.cpp

// native_bridge/juce_fx/JuceFxGuiHost.cpp
// M2 implementation: GUI thread + PluginWindow host. Lịch sử fix:
//  - tick 30ms = pumpEditorQueue + reconcile (editor Component chỉ đụng trên
//    message thread — mọi JUCE GUI op chạy trong GUI thread này).
//  - KHÔNG dùng juce::Timer cho cadence: timer không fire trên GUI thread
//    riêng (0 tick trong selftest) — guiMain dùng inline steady_clock 30ms
//    quanh runDispatchLoopUntil(10), tick() chạy trên message thread.
//  - stop(): waitEditorsClosed(1s) → quit → join 2s → detach nếu kẹt
//    (plugin editor block message thread); teardown còn editor thì close
//    TRƯỚC shutdownJuce_GUI (JUCE assert editor phải xoá trước MM).
//  - reconcile erase window khi !isEditorOpen (sau re-prepare editors clear);
//    hide = setVisible(false) GIỮ window object (editor + instance sống).
#include "JuceFxGuiHost.h"
#include "JuceFxEngine.h"

#include <juce_gui_basics/juce_gui_basics.h>

#ifdef _WIN32
#ifndef NOMINMAX
#define NOMINMAX
#endif
#include <windows.h>
#endif

#include <algorithm>
#include <chrono>
#include <condition_variable>
#include <cstdint>
#include <functional>
#include <iostream>
#include <mutex>
#include <thread>
#include <utility>
#include <vector>

namespace {

// Window host cho editor của slot (engine sở hữu editor — window không xoá).
class PluginWindow final : public juce::DocumentWindow {
public:
    PluginWindow(uint32_t slot, juce::Component* editor, JuceFxGuiHost& host)
        : juce::DocumentWindow("FX slot " + juce::String((int)slot),
                               juce::Colours::darkgrey,
                               juce::DocumentWindow::allButtons,
                               true),  // addToDesktop — native window thật
          slot(slot),
          host_(host) {
        setUsingNativeTitleBar(true);
        setResizable(true, false);  // user resize được; resizeToFit co theo editor
        // resizeToFitWhenContentChangesSize=true: window duy trì kích thước ôm
        // editor (plugin đổi size → window theo). Engine vẫn sở hữu editor.
        setContentNonOwned(editor, true);
    }

    // X button → Close editor (giữ instance DSP + state — mở lại nhanh như
    // Reaper). Tick sau: pump Close → reconcile xoá window này.
    void closeButtonPressed() override { host_.onWindowClose(slot); }

    const uint32_t slot;

private:
    JuceFxGuiHost& host_;
};

}  // namespace

struct JuceFxGuiHost::Impl {
    // Chỉ GUI thread chạm; stop() join GUI thread trước khi ~GuiHost.
    std::vector<std::unique_ptr<PluginWindow>> windows_;
    // runOnGui task queue: main thread xếp (engine.prepare/shutdown phải chạy
    // trên GUI thread — thread tạo plugin instance); GUI thread drain mỗi vòng.
    std::mutex guiMutex;
    std::condition_variable guiCv;
    std::vector<std::function<void()>> guiTasks;
    uint64_t guiTaskDone = 0;  // số task đã hoàn thành (runOnGui chờ tăng)
};

JuceFxGuiHost::JuceFxGuiHost(JuceFxEngine& engine)
    : impl_(std::make_unique<Impl>()), engine_(engine) {}

JuceFxGuiHost::~JuceFxGuiHost() { stop(); }

void JuceFxGuiHost::start() {
    if (started_.exchange(true)) return;
    quit_ = false;
    guiExited_ = false;
    thread_ = std::thread([this] { guiMain(); });
}

void JuceFxGuiHost::stop() {
    if (!started_.load()) return;
    std::cerr << "[JuceFxGuiHost] stop begin" << std::endl;
    waitEditorsClosed(1000);  // started_ vẫn true → có pump từ GUI thread
    started_.store(false);
    quit_ = true;
    // Chờ guiMain thoát tối đa 2s (runDispatchLoopUntil trả sau <=50ms; kẹt
    // khi plugin editor block message thread). Kẹt → detach, không treo audio
    // loop; teardown lệch có thể xảy ra nhưng editor block là pathological.
    for (int i = 0; i < 200 && !guiExited_.load(); ++i)
        std::this_thread::sleep_for(std::chrono::milliseconds(10));
    if (guiExited_.load() && thread_.joinable()) {
        thread_.join();
        std::cerr << "[JuceFxGuiHost] stop joined" << std::endl;
    } else if (thread_.joinable()) {
        std::cerr << "[JuceFxGuiHost] GUI thread không thoát trong 2s — detach"
                  << std::endl;
        thread_.detach();
    }
}

void JuceFxGuiHost::enqueueGuiTask(std::function<void()> task) {
    // GUI không chạy / đang thoát → chạy inline (không có message thread).
    if (!started_.load() || quit_.load() || guiExited_.load()) {
        task();
        return;
    }
    std::unique_lock<std::mutex> lk(impl_->guiMutex);
    const uint64_t before = impl_->guiTaskDone;
    impl_->guiTasks.push_back(std::move(task));
    impl_->guiCv.wait(lk, [&] { return impl_->guiTaskDone > before; });
}

void JuceFxGuiHost::waitEditorsClosed(uint32_t timeoutMs) {
    if (!started_.load()) return;
    engine_.closeAllEditors();  // enqueue Close mọi editor mở
    const auto t0 = std::chrono::steady_clock::now();
    while (engine_.hasOpenEditor()) {
        const auto el =
            std::chrono::duration_cast<std::chrono::milliseconds>(
                std::chrono::steady_clock::now() - t0)
                .count();
        if ((uint32_t)el >= timeoutMs) break;
        std::this_thread::sleep_for(std::chrono::milliseconds(5));
    }
}

void JuceFxGuiHost::onWindowClose(uint32_t slot) {
    engine_.requestEditor(slot, JuceFxEngine::EditorAction::Close);
}

void JuceFxGuiHost::tick() {
    static int n = 0;
    if (++n <= 3 || n % 100 == 0)
        std::cerr << "[JuceFxGuiHost] tick " << n << std::endl;
    engine_.pumpEditorQueue();
    reconcile();
}

void JuceFxGuiHost::reconcile() {
    const uint32_t n = engine_.slotCount();
    auto& windows = impl_->windows_;
    // Xoá window: slot hết chain hoặc editor đã đóng (Close pump / re-prepare
    // clear editors). ~DocumentWindow trên GUI thread; content editor có thể
    // đã bị engine xoá — ResizableWindow giữ SafePointer nên an toàn.
    for (auto it = windows.begin(); it != windows.end();) {
        if ((*it)->slot >= n || !engine_.isEditorOpen((*it)->slot)) {
            it = windows.erase(it);
        } else {
            ++it;
        }
    }
    // Tạo window cho slot đang mở; ẩn/hiện theo flag visible (Hide giữ window).
    for (uint32_t s = 0; s < n; ++s) {
        if (!engine_.isEditorOpen(s)) continue;
        auto it = std::find_if(windows.begin(), windows.end(),
                               [s](const std::unique_ptr<PluginWindow>& w) {
                                   return w->slot == s;
                               });
        if (it != windows.end()) {
            const bool vis = engine_.isEditorVisible(s);
            if ((*it)->isVisible() != vis) (*it)->setVisible(vis);
            continue;
        }
        auto* ed = static_cast<juce::Component*>(engine_.editorHandle(s));
        if (!ed) continue;  // open nhưng handle chưa sẵn — tick sau
        auto w = std::make_unique<PluginWindow>(s, ed, *this);
        w->setVisible(engine_.isEditorVisible(s));
        if (auto* peer = w->getPeer()) {
            const auto hwnd = (uintptr_t)peer->getNativeHandle();
            std::cerr << "[JuceFxGuiHost] window slot " << (int)s
                      << " hwnd=0x" << std::hex << hwnd << std::dec
                      << " editor=" << ed->getWidth() << "x" << ed->getHeight()
                      << std::endl;
        }
        windows.push_back(std::move(w));
    }
    winCount_.store((uint32_t)windows.size());
}

void JuceFxGuiHost::guiMain() {
#ifdef _WIN32
    // BELOW_NORMAL: GUI spike không preempt audio thread HIGHEST.
    SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_BELOW_NORMAL);
#endif
    // Thread này trở thành JUCE message thread.
    std::cerr << "[JuceFxGuiHost] guiMain start" << std::endl;
    juce::initialiseJuce_GUI();
    std::cerr << "[JuceFxGuiHost] initialiseJuce_GUI ok" << std::endl;
    // Cadence inline 30ms — KHÔNG dùng juce::Timer: trên GUI thread riêng,
    // timer callback không bao giờ fire dù runDispatchLoopUntil pump liên tục
    // (test cho thấy 0 tick). tick() ở đây chạy trên chính message thread nên
    // pump + tạo/xoá Component an toàn.
    {
        using clock = std::chrono::steady_clock;
        const auto tickMs = std::chrono::milliseconds(30);
        auto lastTick = clock::now();
        while (!quit_.load()) {
            // Drain runOnGui tasks trước mỗi pump: engine.prepare()/shutdown()
            // phải chạy trên GUI thread (= thread tạo plugin instance — M2b).
            for (;;) {
                std::function<void()> t;
                {
                    std::lock_guard<std::mutex> lk(impl_->guiMutex);
                    if (impl_->guiTasks.empty()) break;
                    t = std::move(impl_->guiTasks.front());
                    impl_->guiTasks.erase(impl_->guiTasks.begin());
                }
                if (t) t();
                {
                    std::lock_guard<std::mutex> lk(impl_->guiMutex);
                    ++impl_->guiTaskDone;
                }
                impl_->guiCv.notify_all();
            }
            juce::MessageManager::getInstance()->runDispatchLoopUntil(10);
            const auto now = clock::now();
            if (now - lastTick >= tickMs) {
                tick();
                lastTick = now;
            }
        }
        std::cerr << "[JuceFxGuiHost] loop exit" << std::endl;
    }
    // Teardown order: editor là JUCE Component — xoá TRƯỚC shutdownJuce_GUI.
    std::cerr << "[JuceFxGuiHost] teardown begin" << std::endl;
    engine_.closeAllEditors();
    std::cerr << "[JuceFxGuiHost] teardown closeAllEditors ok" << std::endl;
    engine_.pumpEditorQueue();  // xử lý Close đồng bộ (message thread)
    std::cerr << "[JuceFxGuiHost] teardown pump ok" << std::endl;
    impl_->windows_.clear();    // ~PluginWindow trên message thread
    std::cerr << "[JuceFxGuiHost] teardown windows clear ok" << std::endl;
    juce::shutdownJuce_GUI();
    std::cerr << "[JuceFxGuiHost] teardown done" << std::endl;
    guiExited_ = true;
}