#include "SceneManager.h"
#include "SelectionManager.h"
#include <algorithm>

namespace UI {

EntityID SceneManager::CreateEntity(const std::string& name, EntityID parent) {
    EntityID id = m_nextEntityId++;
    GameObject entity;
    entity.id = id;
    entity.name = name;
    entity.parent = parent;
    m_entities[id] = std::move(entity);

    if (parent != INVALID_ENTITY_ID) {
        m_entities[parent].children.push_back(id);
    } else {
        m_rootEntities.push_back(id);
    }

    OnEntityCreated.Invoke(id);
    return id;
}

void SceneManager::DeleteEntity(EntityID id) {
    auto it = m_entities.find(id);
    if (it == m_entities.end()) return;

    GameObject& entity = it->second;

    std::vector<EntityID> childrenToDelete = entity.children;
    for (EntityID childId : childrenToDelete) {
        DeleteEntity(childId);
    }

    if (entity.parent != INVALID_ENTITY_ID) {
        auto* parent = GetEntity(entity.parent);
        if (parent) {
            auto& siblings = parent->children;
            siblings.erase(std::remove(siblings.begin(), siblings.end(), id), siblings.end());
        }
    } else {
        m_rootEntities.erase(std::remove(m_rootEntities.begin(), m_rootEntities.end(), id), m_rootEntities.end());
    }

    if (SelectionManager::Get().GetSelectedEntity() == id) {
        SelectionManager::Get().ClearSelection();
    }

    m_entities.erase(it);
    OnEntityDeleted.Invoke(id);
}

ClipboardData SceneManager::CopyEntityRecursive(const GameObject* entity) {
    ClipboardData data;
    data.name = entity->name;

    for (const auto& comp : entity->components) {
        if (auto* transform = dynamic_cast<const TransformComponent*>(comp.get())) {
            auto newComp = std::make_unique<TransformComponent>();
            memcpy(newComp->position, transform->position, sizeof(transform->position));
            memcpy(newComp->rotation, transform->rotation, sizeof(transform->rotation));
            memcpy(newComp->scale, transform->scale, sizeof(transform->scale));
            data.components.push_back(std::move(newComp));
        }
        else if (auto* meshRenderer = dynamic_cast<const MeshRendererComponent*>(comp.get())) {
            auto newComp = std::make_unique<MeshRendererComponent>();
            newComp->materialName = meshRenderer->materialName;
            newComp->meshName = meshRenderer->meshName;
            data.components.push_back(std::move(newComp));
        }
    }

    for (EntityID childId : entity->children) {
        const GameObject* child = GetEntity(childId);
        if (child) {
            data.children.push_back(CopyEntityRecursive(child));
        }
    }

    return data;
}

void SceneManager::CopyEntity(EntityID id) {
    const GameObject* entity = GetEntity(id);
    if (!entity) return;

    m_clipboard = CopyEntityRecursive(entity);
}

EntityID SceneManager::PasteEntityRecursive(const ClipboardData& data, EntityID parent) {
    EntityID newId = CreateEntity(data.name, parent);
    GameObject* newEntity = GetEntity(newId);

    if (newEntity) {
        newEntity->components.clear();
        for (const auto& comp : data.components) {
            if (auto* transform = dynamic_cast<const TransformComponent*>(comp.get())) {
                auto newComp = std::make_unique<TransformComponent>();
                memcpy(newComp->position, transform->position, sizeof(transform->position));
                memcpy(newComp->rotation, transform->rotation, sizeof(transform->rotation));
                memcpy(newComp->scale, transform->scale, sizeof(transform->scale));
                newEntity->components.push_back(std::move(newComp));
            }
            else if (auto* meshRenderer = dynamic_cast<const MeshRendererComponent*>(comp.get())) {
                auto newComp = std::make_unique<MeshRendererComponent>();
                newComp->materialName = meshRenderer->materialName;
                newComp->meshName = meshRenderer->meshName;
                newEntity->components.push_back(std::move(newComp));
            }
        }
    }

    for (const auto& childData : data.children) {
        PasteEntityRecursive(childData, newId);
    }

    return newId;
}

EntityID SceneManager::PasteEntity(EntityID parent) {
    if (!m_clipboard) return INVALID_ENTITY_ID;
    return PasteEntityRecursive(*m_clipboard, parent);
}

EntityID SceneManager::DuplicateEntity(EntityID id) {
    CopyEntity(id);
    const GameObject* entity = GetEntity(id);
    if (!entity) return INVALID_ENTITY_ID;
    return PasteEntity(entity->parent);
}

void SceneManager::MoveEntity(EntityID id, EntityID newParent) {
    GameObject* entity = GetEntity(id);
    if (!entity || id == newParent) return;

    if (entity->parent != INVALID_ENTITY_ID) {
        GameObject* oldParent = GetEntity(entity->parent);
        if (oldParent) {
            auto& siblings = oldParent->children;
            siblings.erase(std::remove(siblings.begin(), siblings.end(), id), siblings.end());
        }
    } else {
        m_rootEntities.erase(std::remove(m_rootEntities.begin(), m_rootEntities.end(), id), m_rootEntities.end());
    }

    entity->parent = newParent;

    if (newParent != INVALID_ENTITY_ID) {
        GameObject* newParentEntity = GetEntity(newParent);
        if (newParentEntity) {
            newParentEntity->children.push_back(id);
        }
    } else {
        m_rootEntities.push_back(id);
    }

    OnEntityChanged.Invoke(id);
}

void SceneManager::CreateDemoScene() {
    m_entities.clear();
    m_rootEntities.clear();
    m_nextEntityId = 1;
    m_clipboard.reset();

    EntityID camera = CreateEntity("Main Camera");
    GetEntity(camera)->AddComponent<TransformComponent>();

    EntityID light = CreateEntity("Directional Light");

    EntityID cube = CreateEntity("Cube");
    GetEntity(cube)->AddComponent<TransformComponent>();
    GetEntity(cube)->AddComponent<MeshRendererComponent>()->meshName = "Cube Mesh";

    EntityID sphere = CreateEntity("Sphere");
    GetEntity(sphere)->AddComponent<TransformComponent>();
    GetEntity(sphere)->AddComponent<MeshRendererComponent>()->meshName = "Sphere Mesh";

    EntityID player = CreateEntity("Player");
    EntityID weapon = CreateEntity("Weapon", player);

    OnSceneChanged.Invoke();
}

}