//
// Urho3D Engine
// Copyright (c) 2008-2011 Lasse Öörni
//
// 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 "Frustum.h"
#include "Component.h"
#include "Node.h"
#include "Ray.h"

static const unsigned VOF_NONE = 0x0;
static const unsigned VOF_LOW_MATERIAL_QUALITY = 0x1;
static const unsigned VOF_DISABLE_SHADOWS = 0x2;
static const unsigned VOF_DISABLE_OCCLUSION = 0x4;

/// Camera component
class Camera : public Component
{
    OBJECT(Camera);
    
public:
    /// Construct
    Camera(Context* context);
    /// Destruct
    virtual ~Camera();
    /// Register object factory
    static void RegisterObject(Context* context);
    
    /// Set near clip distance
    void SetNearClip(float nearClip);
    /// Set far clip distance
    void SetFarClip(float farClip);
    /// Set field of view
    void SetFov(float fov);
    /// Set orthographic mode view uniform size
    void SetOrthoSize(float orthoSize);
    /// Set orthographic mode view size
    void SetOrthoSize(const Vector2& orthoSize);
    /// Set aspect ratio
    void SetAspectRatio(float aspectRatio);
    /// Set zoom
    void SetZoom(float zoom);
    /// Set LOD bias
    void SetLodBias(float bias);
    /// Set view mask. Will be and'ed with object's view mask to see if the object should be rendered
    void SetViewMask(unsigned mask);
    /// Set view override flags
    void SetViewOverrideFlags(unsigned flags);
    /// Set orthographic mode enabled/disabled
    void SetOrthographic(bool enable);
    /// Set automatic aspect ratio based on viewport dimensions
    void SetAutoAspectRatio(bool enable);
    /// Set projection jitter offset. It needs to be Calculated as (offset in pixels) / (viewport dimensions)
    void SetProjectionOffset(const Vector2& offset);
    
    /// Return far clip distance
    float GetFarClip() const { return farClip_; }
    /// Return near clip distance
    float GetNearClip() const;
    /// Return field of view
    float GetFov() const { return fov_; }
    /// Return orthographic mode size
    float GetOrthoSize() const { return orthoSize_; } 
    /// Return aspect ratio
    float GetAspectRatio() const { return aspectRatio_; }
    /// Return zoom
    float GetZoom() const { return zoom_; }
    /// Return LOD bias
    float GetLodBias() const { return lodBias_; }
    /// Return view mask
    unsigned GetViewMask() const { return viewMask_; }
    /// Return view override flags
    unsigned GetViewOverrideFlags() const { return viewOverrideFlags_; }
    /// Return orthographic flag
    bool IsOrthographic() const { return orthographic_; }
    /// Return auto aspect ratio flag
    bool GetAutoAspectRatio() const { return autoAspectRatio_; }
    /// Return frustum in world space
    Frustum GetFrustum() const;
    /// Return projection matrix
    Matrix4 GetProjection(bool enableOffset = true) const;
    /// Return frustum near and far sizes
    void GetFrustumSize(Vector3& near, Vector3& far) const;
    /// Return half view size
    float GetHalfViewSize() const;
    /// Return frustum transformed to view space
    Frustum GetViewSpaceFrustum() const;
    /// Return frustum split by custom near and far clip distances
    Frustum GetSplitFrustum(float nearClip, float farClip);
    /// Return ray corresponding to screen coordinates (0.0 to 1.0)
    Ray GetScreenRay(float x, float y);
    /// Return forward vector
    Vector3 GetForwardVector();
    /// Return right vector
    Vector3 GetRightVector();
    /// Return up vector
    Vector3 GetUpVector();
    /// Return projection jitter offset
    const Vector2& GetProjectionOffset() const { return projectionOffset_; }
    /// Return distance to position. In orthographic mode uses only Z coordinate
    float GetDistance(const Vector3& worldPos);
    /// Return squared distance to position. In orthographic mode uses only Z coordinate
    float GetDistanceSquared(const Vector3& worldPos);
    /// Return a scene node's LOD scaled distance
    float GetLodDistance(float distance, float scale, float bias) const;
    
    /// Return inverse world transform
    Matrix4x3 GetInverseWorldTransform() const
    {
        return GetWorldTransform().GetInverse();
    }

private:
    /// Near clip distance
    float nearClip_;
    /// Far clip distance
    float farClip_;
    /// Field of view
    float fov_;
    /// Orthographic view size
    float orthoSize_;
    /// Aspect ratio
    float aspectRatio_;
    /// Zoom
    float zoom_;
    /// LOD bias
    float lodBias_;
    /// View mask
    unsigned viewMask_;
    /// View override flags
    unsigned viewOverrideFlags_;
    /// Orthographic mode flag
    bool orthographic_;
    /// Auto aspect ratio flag
    bool autoAspectRatio_;
    /// Projection jitter offset
    Vector2 projectionOffset_;
};