// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "flutter/shell/platform/windows/public/flutter_windows.h"

#include <io.h>

#include <algorithm>
#include <cassert>
#include <chrono>
#include <cstdlib>
#include <filesystem>
#include <iostream>
#include <memory>
#include <vector>

#include "flutter/shell/platform/common/cpp/client_wrapper/include/flutter/plugin_registrar.h"
#include "flutter/shell/platform/common/cpp/incoming_message_dispatcher.h"
#include "flutter/shell/platform/common/cpp/path_utils.h"
#include "flutter/shell/platform/embedder/embedder.h"
#include "flutter/shell/platform/windows/flutter_project_bundle.h"
#include "flutter/shell/platform/windows/flutter_windows_engine.h"
#include "flutter/shell/platform/windows/flutter_windows_view.h"
#include "flutter/shell/platform/windows/window_binding_handler.h"
#include "flutter/shell/platform/windows/window_state.h"

static_assert(FLUTTER_ENGINE_VERSION == 1, "");

// Returns the engine corresponding to the given opaque API handle.
static flutter::FlutterWindowsEngine* EngineFromHandle(
    FlutterDesktopEngineRef ref) {
  return reinterpret_cast<flutter::FlutterWindowsEngine*>(ref);
}

// Returns the opaque API handle for the given engine instance.
static FlutterDesktopEngineRef HandleForEngine(
    flutter::FlutterWindowsEngine* engine) {
  return reinterpret_cast<FlutterDesktopEngineRef>(engine);
}

// Returns the view corresponding to the given opaque API handle.
static flutter::FlutterWindowsView* ViewFromHandle(FlutterDesktopViewRef ref) {
  return reinterpret_cast<flutter::FlutterWindowsView*>(ref);
}

// Returns the opaque API handle for the given view instance.
static FlutterDesktopViewRef HandleForView(flutter::FlutterWindowsView* view) {
  return reinterpret_cast<FlutterDesktopViewRef>(view);
}

void FlutterDesktopViewControllerDestroy(
    FlutterDesktopViewControllerRef controller) {
  delete controller;
}

FlutterDesktopEngineRef FlutterDesktopViewControllerGetEngine(
    FlutterDesktopViewControllerRef controller) {
  return HandleForEngine(controller->view->GetEngine());
}

FlutterDesktopViewRef FlutterDesktopViewControllerGetView(
    FlutterDesktopViewControllerRef controller) {
  return HandleForView(controller->view.get());
}

FlutterDesktopEngineRef FlutterDesktopEngineCreate(
    const FlutterDesktopEngineProperties& engine_properties) {
  flutter::FlutterProjectBundle project(engine_properties);
  auto engine = std::make_unique<flutter::FlutterWindowsEngine>(project);
  return HandleForEngine(engine.release());
}

bool FlutterDesktopEngineDestroy(FlutterDesktopEngineRef engine_ref) {
  flutter::FlutterWindowsEngine* engine = EngineFromHandle(engine_ref);
  bool result = true;
  if (engine->running()) {
    result = engine->Stop();
  }
  delete engine;
  return result;
}

bool FlutterDesktopEngineRun(FlutterDesktopEngineRef engine,
                             const char* entry_point) {
  return EngineFromHandle(engine)->RunWithEntrypoint(entry_point);
}

void FlutterDesktopEngineReloadSystemFonts(FlutterDesktopEngineRef engine) {
  EngineFromHandle(engine)->ReloadSystemFonts();
}

FlutterDesktopPluginRegistrarRef FlutterDesktopEngineGetPluginRegistrar(
    FlutterDesktopEngineRef engine,
    const char* plugin_name) {
  // Currently, one registrar acts as the registrar for all plugins, so the
  // name is ignored. It is part of the API to reduce churn in the future when
  // aligning more closely with the Flutter registrar system.

  return EngineFromHandle(engine)->GetRegistrar();
}

FlutterDesktopMessengerRef FlutterDesktopEngineGetMessenger(
    FlutterDesktopEngineRef engine) {
  return EngineFromHandle(engine)->messenger();
}

HWND FlutterDesktopViewGetHWND(FlutterDesktopViewRef view) {
  return std::get<HWND>(*ViewFromHandle(view)->GetRenderTarget());
}

FlutterDesktopViewRef FlutterDesktopPluginRegistrarGetView(
    FlutterDesktopPluginRegistrarRef registrar) {
  return HandleForView(registrar->engine->view());
}

void FlutterDesktopResyncOutputStreams() {
  FILE* unused;
  if (freopen_s(&unused, "CONOUT$", "w", stdout)) {
    _dup2(_fileno(stdout), 1);
  }
  if (freopen_s(&unused, "CONOUT$", "w", stderr)) {
    _dup2(_fileno(stdout), 2);
  }
  std::ios::sync_with_stdio();
}

// Implementations of common/cpp/ API methods.

FlutterDesktopMessengerRef FlutterDesktopPluginRegistrarGetMessenger(
    FlutterDesktopPluginRegistrarRef registrar) {
  return registrar->engine->messenger();
}

void FlutterDesktopPluginRegistrarSetDestructionHandler(
    FlutterDesktopPluginRegistrarRef registrar,
    FlutterDesktopOnPluginRegistrarDestroyed callback) {
  registrar->engine->SetPluginRegistrarDestructionCallback(callback);
}

bool FlutterDesktopMessengerSendWithReply(FlutterDesktopMessengerRef messenger,
                                          const char* channel,
                                          const uint8_t* message,
                                          const size_t message_size,
                                          const FlutterDesktopBinaryReply reply,
                                          void* user_data) {
  return messenger->engine->SendPlatformMessage(channel, message, message_size,
                                                reply, user_data);
}

bool FlutterDesktopMessengerSend(FlutterDesktopMessengerRef messenger,
                                 const char* channel,
                                 const uint8_t* message,
                                 const size_t message_size) {
  return FlutterDesktopMessengerSendWithReply(messenger, channel, message,
                                              message_size, nullptr, nullptr);
}

void FlutterDesktopMessengerSendResponse(
    FlutterDesktopMessengerRef messenger,
    const FlutterDesktopMessageResponseHandle* handle,
    const uint8_t* data,
    size_t data_length) {
  messenger->engine->SendPlatformMessageResponse(handle, data, data_length);
}

void FlutterDesktopMessengerSetCallback(FlutterDesktopMessengerRef messenger,
                                        const char* channel,
                                        FlutterDesktopMessageCallback callback,
                                        void* user_data) {
  messenger->engine->message_dispatcher()->SetMessageCallback(channel, callback,
                                                              user_data);
}