#include "Core/PlaySessionController.h"

#include "Core/EditorEvents.h"
#include "Core/EventBus.h"
#include "Core/IEditorContext.h"
#include "Core/ISceneManager.h"
#include "Core/IUndoManager.h"

namespace XCEngine {
namespace Editor {

void PlaySessionController::Attach(IEditorContext& context) {
    if (m_playStartRequestedHandlerId == 0) {
        m_playStartRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeStartRequestedEvent>(
            [this, &context](const PlayModeStartRequestedEvent&) {
                StartPlay(context);
            });
    }

    if (m_playStopRequestedHandlerId == 0) {
        m_playStopRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeStopRequestedEvent>(
            [this, &context](const PlayModeStopRequestedEvent&) {
                StopPlay(context);
            });
    }

    if (m_playPauseRequestedHandlerId == 0) {
        m_playPauseRequestedHandlerId = context.GetEventBus().Subscribe<PlayModePauseRequestedEvent>(
            [this, &context](const PlayModePauseRequestedEvent&) {
                PausePlay(context);
            });
    }

    if (m_playResumeRequestedHandlerId == 0) {
        m_playResumeRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeResumeRequestedEvent>(
            [this, &context](const PlayModeResumeRequestedEvent&) {
                ResumePlay(context);
            });
    }

    if (m_playStepRequestedHandlerId == 0) {
        m_playStepRequestedHandlerId = context.GetEventBus().Subscribe<PlayModeStepRequestedEvent>(
            [this, &context](const PlayModeStepRequestedEvent&) {
                StepPlay(context);
            });
    }
}

void PlaySessionController::Detach(IEditorContext& context) {
    StopPlay(context);

    if (m_playStartRequestedHandlerId != 0) {
        context.GetEventBus().Unsubscribe<PlayModeStartRequestedEvent>(m_playStartRequestedHandlerId);
        m_playStartRequestedHandlerId = 0;
    }

    if (m_playStopRequestedHandlerId != 0) {
        context.GetEventBus().Unsubscribe<PlayModeStopRequestedEvent>(m_playStopRequestedHandlerId);
        m_playStopRequestedHandlerId = 0;
    }

    if (m_playPauseRequestedHandlerId != 0) {
        context.GetEventBus().Unsubscribe<PlayModePauseRequestedEvent>(m_playPauseRequestedHandlerId);
        m_playPauseRequestedHandlerId = 0;
    }

    if (m_playResumeRequestedHandlerId != 0) {
        context.GetEventBus().Unsubscribe<PlayModeResumeRequestedEvent>(m_playResumeRequestedHandlerId);
        m_playResumeRequestedHandlerId = 0;
    }

    if (m_playStepRequestedHandlerId != 0) {
        context.GetEventBus().Unsubscribe<PlayModeStepRequestedEvent>(m_playStepRequestedHandlerId);
        m_playStepRequestedHandlerId = 0;
    }
}

void PlaySessionController::Update(IEditorContext& context, float deltaTime) {
    (void)context;
    if (!m_runtimeLoop.IsRunning()) {
        return;
    }

    m_runtimeLoop.Tick(deltaTime);
}

bool PlaySessionController::StartPlay(IEditorContext& context) {
    if (context.GetRuntimeMode() != EditorRuntimeMode::Edit) {
        return false;
    }

    auto& sceneManager = context.GetSceneManager();
    if (!sceneManager.HasActiveScene()) {
        return false;
    }

    m_editorSnapshot = sceneManager.CaptureSceneSnapshot();
    if (!m_editorSnapshot.hasScene) {
        return false;
    }

    if (!sceneManager.RestoreSceneSnapshot(m_editorSnapshot)) {
        return false;
    }

    sceneManager.SetSceneDocumentDirtyTrackingEnabled(false);
    m_runtimeLoop.Start(sceneManager.GetScene());
    context.GetUndoManager().ClearHistory();
    context.SetRuntimeMode(EditorRuntimeMode::Play);
    context.GetEventBus().Publish(PlayModeStartedEvent{});
    return true;
}

bool PlaySessionController::StopPlay(IEditorContext& context) {
    if (!IsEditorRuntimeActive(context.GetRuntimeMode())) {
        return false;
    }

    auto& sceneManager = context.GetSceneManager();
    m_runtimeLoop.Stop();
    sceneManager.SetSceneDocumentDirtyTrackingEnabled(true);

    if (!sceneManager.RestoreSceneSnapshot(m_editorSnapshot)) {
        return false;
    }

    context.GetUndoManager().ClearHistory();
    context.SetRuntimeMode(EditorRuntimeMode::Edit);
    context.GetEventBus().Publish(PlayModeStoppedEvent{});
    m_editorSnapshot = {};
    return true;
}

bool PlaySessionController::PausePlay(IEditorContext& context) {
    if (context.GetRuntimeMode() != EditorRuntimeMode::Play || !m_runtimeLoop.IsRunning()) {
        return false;
    }

    m_runtimeLoop.Pause();
    context.SetRuntimeMode(EditorRuntimeMode::Paused);
    context.GetEventBus().Publish(PlayModePausedEvent{});
    return true;
}

bool PlaySessionController::ResumePlay(IEditorContext& context) {
    if (context.GetRuntimeMode() != EditorRuntimeMode::Paused || !m_runtimeLoop.IsRunning()) {
        return false;
    }

    m_runtimeLoop.Resume();
    context.SetRuntimeMode(EditorRuntimeMode::Play);
    context.GetEventBus().Publish(PlayModeResumedEvent{});
    return true;
}

bool PlaySessionController::StepPlay(IEditorContext& context) {
    if (context.GetRuntimeMode() != EditorRuntimeMode::Paused || !m_runtimeLoop.IsRunning()) {
        return false;
    }

    m_runtimeLoop.StepFrame();
    return true;
}

} // namespace Editor
} // namespace XCEngine