//
// Copyright (c) 2008-2014 the Urho3D project.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#pragma once

#include "Matrix3x4.h"
#include "Animatable.h"
#include "VectorBuffer.h"

namespace Urho3D
{

class Component;
class Connection;
class Scene;
class SceneResolver;

struct NodeReplicationState;

/// Component and child node creation mode for networking.
enum CreateMode
{
    REPLICATED = 0,
    LOCAL = 1
};

/// Transform space for translations and rotations.
enum TransformSpace
{
    TS_LOCAL = 0,
    TS_PARENT,
    TS_WORLD
};

/// %Scene node that may contain components and child nodes.
class URHO3D_API Node : public Animatable
{
    OBJECT(Node);
    BASEOBJECT(Node);
    
    friend class Connection;
    
public:
    /// Construct.
    Node(Context* context);
    /// Destruct. Any child nodes are detached.
    virtual ~Node();
    /// Register object factory.
    static void RegisterObject(Context* context);

    /// Handle attribute write access.
    virtual void OnSetAttribute(const AttributeInfo& attr, const Variant& src);
    /// Load from binary data. Return true if successful.
    virtual bool Load(Deserializer& source, bool setInstanceDefault = false);
    /// Load from XML data. Return true if successful.
    virtual bool LoadXML(const XMLElement& source, bool setInstanceDefault = false);
    /// Save as binary data. Return true if successful.
    virtual bool Save(Serializer& dest) const;
    /// Save as XML data. Return true if successful.
    virtual bool SaveXML(XMLElement& dest) const;
    /// Apply attribute changes that can not be applied immediately recursively to child nodes and components.
    virtual void ApplyAttributes();
    /// Return whether should save default-valued attributes into XML. Always save node transforms for readability, even if identity.
    virtual bool SaveDefaultAttributes() const { return true; }
    /// Add a replication state that is tracking this node.
    virtual void AddReplicationState(NodeReplicationState* state);
    
    /// Save to an XML file. Return true if successful.
    bool SaveXML(Serializer& dest) const;
    /// Set name of the scene node. Names are not required to be unique.
    void SetName(const String& name);
    /// Set position in parent space. If the scene node is on the root level (is child of the scene itself), this is same as world space.
    void SetPosition(const Vector3& position);
    /// Set rotation in parent space.
    void SetRotation(const Quaternion& rotation);
    /// Set forward direction in parent space. Positive Z axis equals identity rotation.
    void SetDirection(const Vector3& direction);
    /// Set uniform scale in parent space.
    void SetScale(float scale);
    /// Set scale in parent space.
    void SetScale(const Vector3& scale);
    /// Set both position and rotation in parent space as an atomic operation. This is faster than setting position and rotation separately.
    void SetTransform(const Vector3& position, const Quaternion& rotation);
    /// Set both position, rotation and uniform scale in parent space as an atomic operation.
    void SetTransform(const Vector3& position, const Quaternion& rotation, float scale);
    /// Set both position, rotation and scale in parent space as an atomic operation.
    void SetTransform(const Vector3& position, const Quaternion& rotation, const Vector3& scale);
    /// Set position in world space.
    void SetWorldPosition(const Vector3& position);
    /// Set rotation in world space.
    void SetWorldRotation(const Quaternion& rotation);
    /// Set forward direction in world space.
    void SetWorldDirection(const Vector3& direction);
    /// Set uniform scale in world space.
    void SetWorldScale(float scale);
    /// Set scale in world space.
    void SetWorldScale(const Vector3& scale);
    /// Set both position and rotation in world space as an atomic operation.
    void SetWorldTransform(const Vector3& position, const Quaternion& rotation);
    /// Set both position, rotation and uniform scale in world space as an atomic operation.
    void SetWorldTransform(const Vector3& position, const Quaternion& rotation, float scale);
    /// Set both position, rotation and scale in world space as an atomic opration.
    void SetWorldTransform(const Vector3& position, const Quaternion& rotation, const Vector3& scale);
    /// Move the scene node in the chosen transform space.
    void Translate(const Vector3& delta, TransformSpace space = TS_LOCAL);
    /// Rotate the scene node in the chosen transform space.
    void Rotate(const Quaternion& delta, TransformSpace space = TS_LOCAL);
    /// Rotate around a point in the chosen transform space.
    void RotateAround(const Vector3& point, const Quaternion& delta, TransformSpace space = TS_LOCAL);
    /// Rotate around the X axis.
    void Pitch(float angle, TransformSpace space = TS_LOCAL);
    /// Rotate around the Y axis.
    void Yaw(float angle, TransformSpace space = TS_LOCAL);
    /// Rotate around the Z axis.
    void Roll(float angle, TransformSpace space = TS_LOCAL);
    /// Look at a target position in the chosen transform space. Note that the up vector is always specified in world space. Return true if successful, or false if resulted in an illegal rotation, in which case the current rotation remains.
    bool LookAt(const Vector3& target, const Vector3& up = Vector3::UP, TransformSpace space = TS_WORLD);
    /// Modify scale in parent space uniformly.
    void Scale(float scale);
    /// Modify scale in parent space.
    void Scale(const Vector3& scale);
    /// Set enabled/disabled state without recursion. Components in a disabled node become effectively disabled regardless of their own enable/disable state.
    void SetEnabled(bool enable);
    /// Set enabled/disabled state with optional recursion.
    void SetEnabled(bool enable, bool recursive);
    /// Set owner connection for networking.
    void SetOwner(Connection* owner);
    /// Mark node and child nodes to need world transform recalculation. Notify listener components.
    void MarkDirty();
    /// Create a child scene node (with specified ID if provided).
    Node* CreateChild(const String& name = String::EMPTY, CreateMode mode = REPLICATED, unsigned id = 0);
    /// Add a child scene node at a specific index. If index is not explicitly specified or is greater than current children size, append the new child at the end.
    void AddChild(Node* node, unsigned index = M_MAX_UNSIGNED);
    /// Remove a child scene node.
    void RemoveChild(Node* node);
    /// Remove all child scene nodes.
    void RemoveAllChildren();
    /// Remove child scene nodes that match criteria.
    void RemoveChildren(bool removeReplicated, bool removeLocal, bool recursive);
    /// Create a component to this node (with specified ID if provided).
    Component* CreateComponent(ShortStringHash type, CreateMode mode = REPLICATED, unsigned id = 0);
    /// Create a component to this node if it does not exist already.
    Component* GetOrCreateComponent(ShortStringHash type, CreateMode mode = REPLICATED, unsigned id = 0);
    /// Remove a component from this node.
    void RemoveComponent(Component* component);
    /// Remove the first component of specific type from this node.
    void RemoveComponent(ShortStringHash type);
    /// Remove all components from this node.
    void RemoveAllComponents();
    /// Remove components that match criteria.
    void RemoveComponents(bool removeReplicated, bool removeLocal);
    /// Clone scene node, components and child nodes. Return the clone.
    Node* Clone(CreateMode mode = REPLICATED);
    /// Remove from the parent node. If no other shared pointer references exist, causes immediate deletion.
    void Remove();
    /// Set parent scene node. Retains the world transform.
    void SetParent(Node* parent);
    /// Set a user variable.
    void SetVar(ShortStringHash key, const Variant& value);
    /// Add listener component that is notified of node being dirtied. Can either be in the same node or another.
    void AddListener(Component* component);
    /// Remove listener component.
    void RemoveListener(Component* component);
    /// Template version of creating a component.
    template <class T> T* CreateComponent(CreateMode mode = REPLICATED, unsigned id = 0);
    /// Template version of getting or creating a component.
    template <class T> T* GetOrCreateComponent(CreateMode mode = REPLICATED, unsigned id = 0);
    /// Template version of removing a component.
    template <class T> void RemoveComponent();

    /// Return ID.
    unsigned GetID() const { return id_; }
    /// Return name.
    const String& GetName() const { return name_; }
    /// Return name hash.
    StringHash GetNameHash() const { return nameHash_; }
    /// Return parent scene node.
    Node* GetParent() const { return parent_; }
    /// Return scene.
    Scene* GetScene() const { return scene_; }
    /// Return whether is enabled. Disables nodes effectively disable all their components.
    bool IsEnabled() const { return enabled_; }
    /// Return owner connection in networking.
    Connection* GetOwner() const { return owner_; }
    /// Return position in parent space.
    const Vector3& GetPosition() const { return position_; }
    /// Return rotation in parent space.
    const Quaternion& GetRotation() const { return rotation_; }
    /// Return forward direction in parent space. Positive Z axis equals identity rotation.
    Vector3 GetDirection() const { return rotation_ * Vector3::FORWARD; }
    /// Return up direction in parent space. Positive Y axis equals identity rotation.
    Vector3 GetUp() const { return rotation_ * Vector3::UP; }
    /// Return right direction in parent space. Positive X axis equals identity rotation.
    Vector3 GetRight() const { return rotation_ * Vector3::RIGHT; }

    /// Return scale in parent space.
    const Vector3& GetScale() const { return scale_; }
    /// Return parent space transform matrix.
    Matrix3x4 GetTransform() const { return Matrix3x4(position_, rotation_, scale_); }

    /// Return position in world space.
    Vector3 GetWorldPosition() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldTransform_.Translation();
    }

    /// Return rotation in world space.
    Quaternion GetWorldRotation() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldRotation_;
    }

    /// Return direction in world space.
    Vector3 GetWorldDirection() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldRotation_ * Vector3::FORWARD;
    }

    /// Return node's up vector in world space.
    Vector3 GetWorldUp() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldRotation_ * Vector3::UP;
    }

    /// Return node's right vector in world space.
    Vector3 GetWorldRight() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldRotation_ * Vector3::RIGHT;
    }

    /// Return scale in world space.
    Vector3 GetWorldScale() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldTransform_.Scale();
    }

    /// Return world space transform matrix.
    const Matrix3x4& GetWorldTransform() const
    {
        if (dirty_)
            UpdateWorldTransform();
        
        return worldTransform_;
    }

    /// Convert a local space position to world space.
    Vector3 LocalToWorld(const Vector3& position) const;
    /// Convert a local space position or rotation to world space.
    Vector3 LocalToWorld(const Vector4& vector) const;
    /// Convert a world space position to local space.
    Vector3 WorldToLocal(const Vector3& position) const;
    /// Convert a world space position or rotation to local space.
    Vector3 WorldToLocal(const Vector4& vector) const;
    /// Return whether transform has changed and world transform needs recalculation.
    bool IsDirty() const { return dirty_; }
    /// Return number of child scene nodes.
    unsigned GetNumChildren(bool recursive = false) const;
    /// Return immediate child scene nodes.
    const Vector<SharedPtr<Node> >& GetChildren() const { return children_; }
    /// Return child scene nodes, optionally recursive.
    void GetChildren(PODVector<Node*>& dest, bool recursive = false) const;
    /// Return child scene nodes with a specific component.
    void GetChildrenWithComponent(PODVector<Node*>& dest, ShortStringHash type, bool recursive = false) const;
    /// Return child scene node by index.
    Node* GetChild(unsigned index) const;
    /// Return child scene node by name.
    Node* GetChild(const String& name, bool recursive = false) const;
    /// Return child scene node by name.
    Node* GetChild(const char* name, bool recursive = false) const;
    /// Return child scene node by name hash.
    Node* GetChild(StringHash nameHash, bool recursive = false) const;
    /// Return number of components.
    unsigned GetNumComponents() const { return components_.Size(); }
    /// Return number of non-local components.
    unsigned GetNumNetworkComponents() const;
    /// Return all components.
    const Vector<SharedPtr<Component> >& GetComponents() const { return components_; }
    /// Return all components of type. Optionally recursive.
    void GetComponents(PODVector<Component*>& dest, ShortStringHash type, bool recursive = false) const;
    /// Return component by type. If there are several, returns the first.
    Component* GetComponent(ShortStringHash type) const;
    /// Return whether has a specific component.
    bool HasComponent(ShortStringHash type) const;
    /// Return listener components.
    const Vector<WeakPtr<Component> > GetListeners() const { return listeners_; }
    /// Return a user variable.
    const Variant& GetVar(ShortStringHash key) const;
    /// Return all user variables.
    const VariantMap& GetVars() const { return vars_; }
    /// Return first component derived from class.
    template <class T> T* GetDerivedComponent() const;
    /// Return components derived from class.
    template <class T> void GetDerivedComponents(PODVector<T*>& dest) const;
    /// Template version of returning child nodes with a specific component.
    template <class T> void GetChildrenWithComponent(PODVector<Node*>& dest, bool recursive = false) const;
    /// Template version of returning a component by type.
    template <class T> T* GetComponent() const;
    /// Template version of returning all components of type.
    template <class T> void GetComponents(PODVector<T*>& dest, bool recursive = false) const;
    /// Template version of checking whether has a specific component.
    template <class T> bool HasComponent() const;

    /// Set ID. Called by Scene.
    void SetID(unsigned id);
    /// Set scene. Called by Scene.
    void SetScene(Scene* scene);
    /// Reset scene. Called by Scene.
    void ResetScene();
    /// Set network position attribute.
    void SetNetPositionAttr(const Vector3& value);
    /// Set network rotation attribute.
    void SetNetRotationAttr(const PODVector<unsigned char>& value);
    /// Set network parent attribute.
    void SetNetParentAttr(const PODVector<unsigned char>& value);
    /// Return network position attribute.
    const Vector3& GetNetPositionAttr() const;
    /// Return network rotation attribute.
    const PODVector<unsigned char>& GetNetRotationAttr() const;
    /// Return network parent attribute.
    const PODVector<unsigned char>& GetNetParentAttr() const;
    /// Load components and optionally load child nodes.
    bool Load(Deserializer& source, SceneResolver& resolver, bool loadChildren = true, bool rewriteIDs = false, CreateMode mode = REPLICATED);
    /// Load components from XML data and optionally load child nodes.
    bool LoadXML(const XMLElement& source, SceneResolver& resolver, bool loadChildren = true, bool rewriteIDs = false, CreateMode mode = REPLICATED);
    /// Return the depended on nodes to order network updates.
    const PODVector<Node*>& GetDependencyNodes() const { return dependencyNodes_; }
    /// Prepare network update by comparing attributes and marking replication states dirty as necessary.
    void PrepareNetworkUpdate();
    /// Clean up all references to a network connection that is about to be removed.
    void CleanupConnection(Connection* connection);
    /// Mark for attribute check on the next network update.
    void MarkNetworkUpdate();
    /// Mark node dirty in scene replication states.
    void MarkReplicationDirty();
    /// Create a child node with specific ID.
    Node* CreateChild(unsigned id, CreateMode mode);
    /// Add a pre-created component.
    void AddComponent(Component* component, unsigned id, CreateMode mode);
    /// Calculate number of non-temporary child nodes.
    unsigned GetNumPersistentChildren() const;
    /// Calculate number of non-temporary components.
    unsigned GetNumPersistentComponents() const;
    
protected:
    /// Handle attribute animation added.
    virtual void OnAttributeAnimationAdded();
    /// Handle attribute animation removed.
    virtual void OnAttributeAnimationRemoved();

    /// User variables.
    VariantMap vars_;

private:
    /// Create component, allowing UnknownComponent if actual type is not supported. Leave typeName empty if not known.
    Component* SafeCreateComponent(const String& typeName, ShortStringHash type, CreateMode mode, unsigned id);
    /// Recalculate the world transform.
    void UpdateWorldTransform() const;
    /// Remove child node by iterator.
    void RemoveChild(Vector<SharedPtr<Node> >::Iterator i);
    /// Return child nodes recursively.
    void GetChildrenRecursive(PODVector<Node*>& dest) const;
    /// Return child nodes with a specific component recursively.
    void GetChildrenWithComponentRecursive(PODVector<Node*>& dest, ShortStringHash type) const;
    /// Return specific components recursively.
    void GetComponentsRecursive(PODVector<Component*>& dest, ShortStringHash type) const;
    /// Clone node recursively.
    Node* CloneRecursive(Node* parent, SceneResolver& resolver, CreateMode mode);
    /// Remove a component from this node with the specified iterator.
    void RemoveComponent(Vector<SharedPtr<Component> >::Iterator i);
    /// Handle attribute animation update event.
    void HandleAttributeAnimationUpdate(StringHash eventType, VariantMap& eventData);

    /// World-space transform matrix.
    mutable Matrix3x4 worldTransform_;
    /// World transform needs update flag.
    mutable bool dirty_;
    /// Network update queued flag.
    bool networkUpdate_;
    /// Enabled flag.
    bool enabled_;
    /// Parent scene node.
    Node* parent_;
    /// Scene (root node.)
    Scene* scene_;
    /// Unique ID within the scene.
    unsigned id_;
    /// Position.
    Vector3 position_;
    /// Rotation.
    Quaternion rotation_;
    /// Scale.
    Vector3 scale_;
    /// World-space rotation.
    mutable Quaternion worldRotation_;
    /// Components.
    Vector<SharedPtr<Component> > components_;
    /// Child scene nodes.
    Vector<SharedPtr<Node> > children_;
    /// Node listeners.
    Vector<WeakPtr<Component> > listeners_;
    /// Nodes this node depends on for network updates.
    PODVector<Node*> dependencyNodes_;
    /// Network owner connection.
    Connection* owner_;
    /// Name.
    String name_;
    /// Name hash.
    StringHash nameHash_;
    /// Attribute buffer for network updates.
    mutable VectorBuffer attrBuffer_;
};

template <class T> T* Node::CreateComponent(CreateMode mode, unsigned id) { return static_cast<T*>(CreateComponent(T::GetTypeStatic(), mode, id)); }
template <class T> T* Node::GetOrCreateComponent(CreateMode mode, unsigned id) { return static_cast<T*>(GetOrCreateComponent(T::GetTypeStatic(), mode, id)); }
template <class T> void Node::RemoveComponent() { RemoveComponent(T::GetTypeStatic()); }
template <class T> void Node::GetChildrenWithComponent(PODVector<Node*>& dest, bool recursive) const { GetChildrenWithComponent(dest, T::GetTypeStatic(), recursive); }
template <class T> T* Node::GetComponent() const { return static_cast<T*>(GetComponent(T::GetTypeStatic())); }
template <class T> void Node::GetComponents(PODVector<T*>& dest, bool recursive) const { GetComponents(reinterpret_cast<PODVector<Component*>&>(dest), T::GetTypeStatic(), recursive); }
template <class T> bool Node::HasComponent() const { return HasComponent(T::GetTypeStatic()); }

template <class T> T* Node::GetDerivedComponent() const
{
    for (Vector<SharedPtr<Component> >::ConstIterator i = components_.Begin(); i != components_.End(); ++i)
    {
        T* component = dynamic_cast<T*>(i->Get());
        if (component)
            return component;
    }

    return 0;
}

template <class T> void Node::GetDerivedComponents(PODVector<T*>& dest) const
{
    dest.Clear();

    for (Vector<SharedPtr<Component> >::ConstIterator i = components_.Begin(); i != components_.End(); ++i)
    {
        T* component = dynamic_cast<T*>(i->Get());
        if (component)
            dest.Push(component);
    }
}

}