/*
 * Copyright (c) Contributors to the Open 3D Engine Project.
 * For complete copyright and license terms please see the LICENSE at the root of this distribution.
 *
 * SPDX-License-Identifier: Apache-2.0 OR MIT
 *
 */
#include "CameraEditorSystemComponent.h"
#include "EditorCameraComponent.h"

#include <AzCore/Component/ComponentApplicationBus.h>
#include <AzCore/Debug/Trace.h>
#include <AzCore/std/functional.h>
#include <AzCore/Math/Vector2.h>
#include <AzCore/Serialization/SerializeContext.h>

#include <AzFramework/Viewport/CameraState.h>
#include <AzFramework/Viewport/ViewportScreen.h>
#include <AzToolsFramework/API/ToolsApplicationAPI.h>
#include <AzToolsFramework/Entity/EditorEntityContextBus.h>
#include <AzToolsFramework/API/EntityCompositionRequestBus.h>
#include <AzToolsFramework/Entity/EditorEntityHelpers.h>
#include <AzToolsFramework/Entity/PrefabEditorEntityOwnershipInterface.h>

#include <AzToolsFramework/API/EditorCameraBus.h>
#include "ViewportCameraSelectorWindow.h"

#include <QAction>
#include <QMenu>

namespace Camera
{
    void CameraEditorSystemComponent::Reflect(AZ::ReflectContext* context)
    {
        if (AZ::SerializeContext* serializeContext = azrtti_cast<AZ::SerializeContext*>(context))
        {
            serializeContext->Class<CameraEditorSystemComponent, AZ::Component>()
                ->Version(1)
            ;

            if (AZ::EditContext* editContext = serializeContext->GetEditContext())
            {
                editContext->Class<CameraEditorSystemComponent>(
                    "Camera Editor Commands", "Performs global camera requests")
                    ->ClassElement(AZ::Edit::ClassElements::EditorData, "")
                        ->Attribute(AZ::Edit::Attributes::Category, "Game")
                        ->Attribute(AZ::Edit::Attributes::AppearsInAddComponentMenu, AZ_CRC("System", 0xc94d118b))
                    ;
            }
        }
    }

    void CameraEditorSystemComponent::Activate()
    {
        AzToolsFramework::EditorContextMenuBus::Handler::BusConnect();
        AzToolsFramework::EditorEvents::Bus::Handler::BusConnect();
        Camera::EditorCameraSystemRequestBus::Handler::BusConnect();
        Camera::CameraViewRegistrationRequestsBus::Handler::BusConnect();
    }

    void CameraEditorSystemComponent::Deactivate()
    {
        Camera::CameraViewRegistrationRequestsBus::Handler::BusDisconnect();
        Camera::EditorCameraSystemRequestBus::Handler::BusDisconnect();
        AzToolsFramework::EditorEvents::Bus::Handler::BusDisconnect();
        AzToolsFramework::EditorContextMenuBus::Handler::BusDisconnect();
    }

    void CameraEditorSystemComponent::PopulateEditorGlobalContextMenu(QMenu* menu, const AZ::Vector2&, int flags)
    {
        if (!(flags & AzToolsFramework::EditorEvents::eECMF_HIDE_ENTITY_CREATION))
        {
            QAction* action = menu->addAction(QObject::tr("Create camera entity from view"));
            const auto prefabEditorEntityOwnershipInterface = AZ::Interface<AzToolsFramework::PrefabEditorEntityOwnershipInterface>::Get();
            if (prefabEditorEntityOwnershipInterface && !prefabEditorEntityOwnershipInterface->IsRootPrefabAssigned())
            {
                action->setEnabled(false);
            }
            else
            {
                QObject::connect(
                    action, &QAction::triggered,
                    [this]()
                    {
                        CreateCameraEntityFromViewport();
                    });
            }
        }
    }

    void CameraEditorSystemComponent::CreateCameraEntityFromViewport()
    {
        AzFramework::CameraState cameraState{};
        AZ::EBusReduceResult<bool, AZStd::logical_or<bool>> aggregator;
        Camera::EditorCameraRequestBus::BroadcastResult(
            aggregator, &Camera::EditorCameraRequestBus::Events::GetActiveCameraState, cameraState);

        AZ_Assert(aggregator.value, "Did not find active camera state");

        AzToolsFramework::ScopedUndoBatch undoBatch("Create Camera Entity");

        // Create new entity
        AZ::EntityId newEntityId;
        AZ::EBusAggregateResults<AZ::EntityId> cameras;
        Camera::CameraBus::BroadcastResult(cameras, &CameraBus::Events::GetCameras);
        AZStd::string newCameraName = AZStd::string::format("Camera%zu", cameras.values.size() + 1);
        AzToolsFramework::EditorEntityContextRequestBus::BroadcastResult(
            newEntityId, &AzToolsFramework::EditorEntityContextRequests::CreateNewEditorEntity, newCameraName.c_str());

        // Add CameraComponent
        AzToolsFramework::AddComponents<EditorCameraComponent>::ToEntities(newEntityId);

        // Set transform to that of the viewport, otherwise default to Identity matrix and 60 degree FOV
        const auto worldFromView = AzFramework::CameraTransform(cameraState);
        const auto cameraTransform = AZ::Transform::CreateFromMatrix3x3AndTranslation(
            AZ::Matrix3x3::CreateFromMatrix4x4(worldFromView), worldFromView.GetTranslation());
        AZ::TransformBus::Event(newEntityId, &AZ::TransformInterface::SetWorldTM, cameraTransform);
        CameraRequestBus::Event(newEntityId, &CameraComponentRequests::SetFov, AZ::RadToDeg(cameraState.m_fovOrZoom));
        undoBatch.MarkEntityDirty(newEntityId);
    }

    void CameraEditorSystemComponent::SetViewForEntity(const AZ::EntityId& id, AZ::RPI::ViewPtr view)
    {
        m_entityViewMap[id] = view;
    }

    AZ::RPI::ViewPtr CameraEditorSystemComponent::GetViewForEntity(const AZ::EntityId& id)
    {
        if (auto viewIndex = m_entityViewMap.find(id); viewIndex != m_entityViewMap.end())
        {
            return viewIndex->second.lock();
        }
        return {};
    }

    void CameraEditorSystemComponent::NotifyRegisterViews()
    {
        RegisterViewportCameraSelectorWindow();
    }
}