/* Copyright (C) 2010 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * 0 A.D. is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "precompiled.h"

#include "simulation2/system/Component.h"
#include "ICmpVisual.h"

#include "ICmpPosition.h"
#include "simulation2/MessageTypes.h"

#include "graphics/Frustum.h"
#include "graphics/Model.h"
#include "graphics/ObjectBase.h"
#include "graphics/ObjectEntry.h"
#include "graphics/Unit.h"
#include "graphics/UnitManager.h"
#include "lib/utf8.h"
#include "maths/Matrix3D.h"
#include "maths/Vector3D.h"
#include "ps/CLogger.h"
#include "renderer/Scene.h"

class CCmpVisualActor : public ICmpVisual
{
public:
	static void ClassInit(CComponentManager& componentManager)
	{
		componentManager.SubscribeToMessageType(MT_Interpolate);
		componentManager.SubscribeToMessageType(MT_RenderSubmit);
		componentManager.SubscribeToMessageType(MT_OwnershipChanged);
	}

	DEFAULT_COMPONENT_ALLOCATOR(VisualActor)

	CUnit* m_Unit;

	// Current animation state
	std::string m_AnimName;
	bool m_AnimOnce;
	float m_AnimSpeed;

	CCmpVisualActor() :
		m_Unit(NULL)
	{
	}

	virtual void Init(const CSimContext& context, const CParamNode& paramNode)
	{
		if (!context.HasUnitManager())
			return; // do nothing if graphics are disabled

		// TODO: we should do some fancy animation of under-construction buildings rising from the ground,
		// but for now we'll just use the foundation actor and ignore the normal one
		std::string name;
		if (paramNode.GetChild("Foundation").IsOk())
			name = utf8_from_wstring(paramNode.GetChild("FoundationActor").ToString());
		else
			name = utf8_from_wstring(paramNode.GetChild("Actor").ToString());

		std::set<CStr> selections;
		m_Unit = context.GetUnitManager().CreateUnit(name, NULL, selections);
		if (!m_Unit)
		{
			// The error will have already been logged
			return;
		}

		SelectAnimation("idle", false, 0.f);

		m_Unit->SetID(GetEntityId()); // TODO: is it safe to be using entity IDs for unit IDs?
	}

	virtual void Deinit(const CSimContext& context)
	{
		if (m_Unit)
		{
			context.GetUnitManager().DeleteUnit(m_Unit);
			m_Unit = NULL;
		}
	}

	virtual void Serialize(ISerializer& serialize)
	{
		// TODO: store the actor name, if !debug and it differs from the template

		if (serialize.IsDebug())
		{
			if (m_Unit == NULL)
				serialize.StringASCII("actor", "[none]", 0, 256);
			else
				serialize.String("actor", m_Unit->GetObject()->m_Base->m_Name, 0, 256);
		}

		// TODO: store random variation. This ought to be synchronised across saved games
		// and networks, so everyone sees the same thing. Saving the list of selection strings
		// would be awfully inefficient, so actors should be changed to (by default) represent
		// variations with a 16-bit RNG seed (selected randomly when creating new units, or
		// when someone hits the "randomise" button in the map editor), only overridden with
		// a list of strings if it really needs to be a specific variation.

		// TODO: store animation state
	}

	virtual void Deserialize(const CSimContext& context, const CParamNode& paramNode, IDeserializer& UNUSED(deserialize))
	{
		Init(context, paramNode);
	}

	virtual void HandleMessage(const CSimContext& context, const CMessage& msg, bool UNUSED(global))
	{
		switch (msg.GetType())
		{
		case MT_Interpolate:
		{
			const CMessageInterpolate& msgData = static_cast<const CMessageInterpolate&> (msg);
			Interpolate(context, msgData.frameTime, msgData.offset);
			break;
		}
		case MT_RenderSubmit:
		{
			const CMessageRenderSubmit& msgData = static_cast<const CMessageRenderSubmit&> (msg);
			RenderSubmit(context, msgData.collector, msgData.frustum, msgData.culling);
			break;
		}
		case MT_OwnershipChanged:
		{
			const CMessageOwnershipChanged& msgData = static_cast<const CMessageOwnershipChanged&> (msg);
			if (m_Unit)
				m_Unit->SetPlayerID(msgData.to);
			break;
		}
		}
	}

	virtual CBound GetBounds()
	{
		if (!m_Unit)
			return CBound();
		return m_Unit->GetModel()->GetBounds();
	}

	virtual CVector3D GetPosition()
	{
		if (!m_Unit)
			return CVector3D(0, 0, 0);
		return m_Unit->GetModel()->GetTransform().GetTranslation();
	}

	virtual void SelectAnimation(std::string name, bool once, float speed)
	{
		if (!m_Unit)
			return;

		if (!isfinite(speed) || speed < 0) // JS 'undefined' converts to NaN, which causes Bad Things
			speed = 0;

		m_AnimName = name;
		m_AnimOnce = once;
		m_AnimSpeed = speed;

		m_Unit->SetAnimationState(name, once, speed);
	}

private:
	void Interpolate(const CSimContext& context, float frameTime, float frameOffset);
	void RenderSubmit(const CSimContext& context, SceneCollector& collector, const CFrustum& frustum, bool culling);
};

REGISTER_COMPONENT_TYPE(VisualActor)

void CCmpVisualActor::Interpolate(const CSimContext& context, float frameTime, float frameOffset)
{
	if (m_Unit == NULL)
		return;

	CmpPtr<ICmpPosition> cmpPosition(context, GetEntityId());
	if (cmpPosition.null())
		return;

	if (!cmpPosition->IsInWorld())
	{
		// TODO: need to hide the unit from rendering
		return;
	}

	CMatrix3D transform(cmpPosition->GetInterpolatedTransform(frameOffset));

	m_Unit->GetModel()->SetTransform(transform);
	m_Unit->UpdateModel(frameTime);
}

void CCmpVisualActor::RenderSubmit(const CSimContext& UNUSED(context), SceneCollector& collector, const CFrustum& frustum, bool culling)
{
	if (m_Unit == NULL)
		return;

	// TODO: need to think about things like LOS here

	CModel* model = m_Unit->GetModel();

	model->ValidatePosition();

	if (culling && !frustum.IsBoxVisible(CVector3D(0, 0, 0), model->GetBounds()))
		return;

	// TODO: model->SetShadingColor(CColor(1.0f, 1.0f, 1.0f, 1.0f) if visible, CColor(0.7f, 0.7f, 0.7f, 1.0f) if hidden in FOW)

	collector.SubmitRecursive(model);
}