////////////////////////////////////////////////////////////////////////////////
// skeleton.cpp
// Author     : Francesco Giordana
// Start Date : January 13, 2005
// Copyright  : (C) 2006 by Francesco Giordana
// Email      : fra.giordana@tiscali.it
////////////////////////////////////////////////////////////////////////////////

/*********************************************************************************
*                                                                                *
*   This program is free software; you can redistribute it and/or modify         *
*   it under the terms of the GNU Lesser General Public License as published by  *
*   the Free Software Foundation; either version 2 of the License, or            *
*   (at your option) any later version.                                          *
*                                                                                *
**********************************************************************************/

#include "skeleton.h"
#include "submesh.h"
#include <maya/MFnMatrixData.h>

namespace OgreMayaExporter
{
	// Constructor
	Skeleton::Skeleton()
	{
		m_joints.clear();
		m_animations.clear();
		m_restorePose = "";
	}


	// Destructor
	Skeleton::~Skeleton()
	{
		clear();
	}


	// Clear skeleton data
	void Skeleton::clear()
	{
		m_joints.clear();
		m_animations.clear();
		m_restorePose = "";
	}


	// Load skeleton data from given skin cluster
	MStatus Skeleton::load(MFnSkinCluster* pSkinCluster,ParamList& params)
	{
		MStatus stat;
		//check for valid skin cluster pointer
		if (!pSkinCluster)
		{
			std::cout << "Could not load skeleton data, no skin cluster specified\n";
			std::cout.flush();
			return MS::kFailure;
		}
		//retrieve and load joints from the skin cluster
		MDagPath jointDag,rootDag;
		MDagPathArray influenceDags;
		int numInfluenceObjs = pSkinCluster->influenceObjects(influenceDags,&stat);
		std::cout << "num influence objects: " << numInfluenceObjs << "\n";
		std::cout.flush();
		for (int i=0; i<numInfluenceObjs; i++)
		{
			jointDag = influenceDags[i];
			if (influenceDags[i].hasFn(MFn::kJoint))
			{
				//retrieve root joint
				rootDag = jointDag;
				while (jointDag.length()>0)
				{
					jointDag.pop();
					if (jointDag.hasFn(MFn::kJoint) && jointDag.length()>0)
						rootDag = jointDag;
				}
				//check if skeleton has already been loaded
				bool skip = false;
				for (int j=0; j<m_joints.size() && !skip; j++)
				{
					//skip skeleton if already loaded
					if (rootDag.partialPathName() == m_joints[j].name)
					{
						skip = true;
					}
				}
				//load joints data from root
				if (!skip)
				{
					// load the skeleton
					std::cout <<  "Loading skeleton with root: " << rootDag.fullPathName().asChar() << "...\n";
					std::cout.flush();
					// save current selection list
					MSelectionList selectionList;
					MGlobal::getActiveSelectionList(selectionList);
					// select the root joint dag
					MGlobal::selectByName(rootDag.fullPathName(),MGlobal::kReplaceList);
					//save current pose (if no pose has been saved yet)
					if (m_restorePose == "")
					{
						MString poseName;
						MGlobal::executeCommand("dagPose -s",poseName,true);
						m_restorePose = poseName;
					}
					//set the skeleton to the desired neutral pose
					if (params.neutralPoseType == NPT_BINDPOSE)
					{
						//disable constraints, IK, etc...
						MGlobal::executeCommand("doEnableNodeItems false all",true);
						// Note: we reset to the bind pose
						MGlobal::executeCommand("dagPose -r -g -bp",true);
					}
					//load joints data
					stat = loadJoint(rootDag,NULL,params,pSkinCluster);
					if (MS::kSuccess == stat)
					{
						std::cout << "OK\n";
						std::cout.flush();
					}
					else
					{
						std::cout << "Failed\n";
						std::cout.flush();
					}
					//restore selection list
					MGlobal::setActiveSelectionList(selectionList,MGlobal::kReplaceList);
				}
			}
		}

		return MS::kSuccess;
	}


	// Load a joint
	MStatus Skeleton::loadJoint(MDagPath& jointDag,joint* parent,ParamList& params,MFnSkinCluster* pSkinCluster)
	{
		MStatus stat;
		int i;
		joint newJoint;
		joint* parentJoint = parent;
		// if it is a joint node translate it and then proceed to child nodes, otherwise skip it
		// and proceed directly to child nodes
		if (jointDag.hasFn(MFn::kJoint))
		{
			MFnIkJoint jointFn(jointDag);
			// Display info
			std::cout << "Loading joint: " << jointFn.fullPathName().asChar();
			std::cout.flush();
			if (parent)
			{
				std::cout << " (parent: " << parent->name.asChar() << ")\n";
				std::cout.flush();
			}
			else
			{
				std::cout << "\n";
				std::cout.flush();
			}
			// Get parent index
			int idx=-1;
			if (parent)
			{
				for (i=0; i<m_joints.size() && idx<0; i++)
				{
					if (m_joints[i].name == parent->name)
						idx=i;
				}
			}
			// Get world bind matrix
			MMatrix bindMatrix = jointDag.inclusiveMatrix();;
			// Calculate local bind matrix
			MMatrix localMatrix;
			if (parent)
				localMatrix = bindMatrix * parent->bindMatrix.inverse();
			else
			{	// root node of skeleton
				localMatrix = bindMatrix;
			}
			// Get translation
			MVector translation = ((MTransformationMatrix)localMatrix).translation(MSpace::kPostTransform);
			if (fabs(translation.x) < PRECISION)
				translation.x = 0;
			if (fabs(translation.y) < PRECISION)
				translation.y = 0;
			if (fabs(translation.z) < PRECISION)
				translation.z = 0;
			// Calculate rotation data
			double qx,qy,qz,qw;
			((MTransformationMatrix)localMatrix).getRotationQuaternion(qx,qy,qz,qw);
			MQuaternion rotation(qx,qy,qz,qw);
			MVector axis;
			double theta;
			rotation.getAxisAngle(axis,theta);
			if (fabs(axis.x) < PRECISION)
				axis.x = 0;
			if (fabs(axis.y) < PRECISION)
				axis.y = 0;
			if (fabs(axis.z) < PRECISION)
				axis.z = 0;
			axis.normalize();
			if (fabs(theta) < PRECISION)
				theta = 0;
			if (axis.length() < 0.5)
			{
				axis.x = 0;
				axis.y = 1;
				axis.z = 0;
				theta = 0;
			}
			// Get joint scale
			double scale[3];
			((MTransformationMatrix)localMatrix).getScale(scale,MSpace::kPostTransform);
			if (fabs(scale[0]) < PRECISION)
				scale[0] = 0;
			if (fabs(scale[1]) < PRECISION)
				scale[1] = 0;
			if (fabs(scale[2]) < PRECISION)
				scale[2] = 0;
			// Set joint info
			newJoint.name = jointFn.partialPathName();
			newJoint.id = m_joints.size();
			newJoint.parentIndex = idx;
			newJoint.bindMatrix = bindMatrix;
			newJoint.localMatrix = localMatrix;
			newJoint.posx = translation.x * params.lum;
			newJoint.posy = translation.y * params.lum;
			newJoint.posz = translation.z * params.lum;
			newJoint.angle = theta;
			newJoint.axisx = axis.x;
			newJoint.axisy = axis.y;
			newJoint.axisz = axis.z;
			newJoint.scalex = scale[0];
			newJoint.scaley = scale[1];
			newJoint.scalez = scale[2];
			newJoint.jointDag = jointDag;
			m_joints.push_back(newJoint);
			// If root is a root joint, save it's index in the roots list
			if (idx < 0)
			{
				m_roots.push_back(m_joints.size() - 1);
			}
			// Get pointer to newly created joint
			parentJoint = &newJoint;
		}
		// Load child joints
		for (i=0; i<jointDag.childCount();i++)
		{
			MObject child;
			child = jointDag.child(i);
			MDagPath childDag = jointDag;
			childDag.push(child);
			loadJoint(childDag,parentJoint,params,pSkinCluster);
		}
		return MS::kSuccess;
	}


	// Load animations
	MStatus Skeleton::loadAnims(ParamList& params)
	{
		//enable constraints, IK, etc...
		MGlobal::executeCommand("doEnableNodeItems true all",true);
		MStatus stat;
		int i;
		// save current time for later restore
		MTime curTime = MAnimControl::currentTime();
		std::cout << "Loading joint animations...\n";
		std::cout.flush();
		// clear animations list
		m_animations.clear();
		// load skeleton animation clips for the whole skeleton
		for (i=0; i<params.skelClipList.size(); i++)
		{
			stat = loadClip(params.skelClipList[i].name,params.skelClipList[i].start,
				params.skelClipList[i].stop,params.skelClipList[i].rate,params);
			if (stat == MS::kSuccess)
			{
				std::cout << "Clip successfully loaded\n";
				std::cout.flush();
			}
			else
			{
				std::cout << "Failed loading clip\n";
				std::cout.flush();
			}
		}
		//restore current time
		MAnimControl::setCurrentTime(curTime);
		return MS::kSuccess;
	}

	// Load an animation clip
	MStatus Skeleton::loadClip(MString clipName,float start,float stop,float rate,ParamList& params)
	{
		MStatus stat;
		int i,j;
		MString msg;
		std::vector<float> times;
		// if skeleton has no joints we can't load the clip
		if (m_joints.size() < 0)
			return MS::kFailure;
		// display clip name
		std::cout << "clip \"" << clipName.asChar() << "\"\n";
		std::cout.flush();
		// calculate times from clip sample rate
		times.clear();
		if (rate <= 0)
		{
			std::cout << "invalid sample rate for the clip (must be >0), we skip it\n";
			std::cout.flush();
			return MS::kFailure;
		}
		for (float t=start; t<stop; t+=rate)
			times.push_back(t);
		times.push_back(stop);
		// get animation length
		float length=0;
		if (times.size() >= 0)
			length = times[times.size()-1] - times[0];
		if (length < 0)
		{
			std::cout << "invalid time range for the clip, we skip it\n";
			std::cout.flush();
			return MS::kFailure;
		}
		// create the animation
		Animation a;
		a.m_name = clipName.asChar();
		a.m_tracks.clear();
		a.m_length = length;
		m_animations.push_back(a);
		int animIdx = m_animations.size() - 1;
		// create a track for current clip for all joints
		std::vector<Track> animTracks;
		for (i=0; i<m_joints.size(); i++)
		{
			Track t;
			t.m_type = TT_SKELETON;
			t.m_bone = m_joints[i].name;
			t.m_skeletonKeyframes.clear();
			animTracks.push_back(t);
		}
		// evaluate animation curves at selected times
		for (i=0; i<times.size(); i++)
		{
			//set time to wanted sample time
			MAnimControl::setCurrentTime(MTime(times[i],MTime::kSeconds));
			//load a keyframe for every joint at current time
			for (j=0; j<m_joints.size(); j++)
			{
				skeletonKeyframe key = loadKeyframe(m_joints[j],times[i]-times[0],params);
				//add keyframe to joint track
				animTracks[j].addSkeletonKeyframe(key);
			}
			if (params.skelBB)
			{
				// Update bounding boxes of loaded submeshes
				for (j=0; j<params.loadedSubmeshes.size(); j++)
				{
					MFnMesh mesh(params.loadedSubmeshes[j]->m_dagPath);
					MPoint min = mesh.boundingBox().min();
					MPoint max = mesh.boundingBox().max();
					MBoundingBox bbox(min,max);
					if (params.exportWorldCoords)
						bbox.transformUsing(params.loadedSubmeshes[j]->m_dagPath.inclusiveMatrix());
					min = bbox.min() * params.lum;
					max = bbox.max() * params.lum;
					MBoundingBox newbbox(min,max);
					params.loadedSubmeshes[j]->m_boundingBox.expand(newbbox);
				}
			}
		}
		// add created tracks to current clip
		for (i=0; i<animTracks.size(); i++)
		{
			m_animations[animIdx].addTrack(animTracks[i]);
		}
		// display info
		std::cout << "length: " << m_animations[animIdx].m_length << "\n";
		std::cout << "num keyframes: " << animTracks[0].m_skeletonKeyframes.size() << "\n";
		std::cout.flush();
		// clip successfully loaded
		return MS::kSuccess;
	}

	// Load a keyframe for a given joint at current time
	skeletonKeyframe Skeleton::loadKeyframe(joint& j,float time,ParamList& params)
	{
		MVector position;
		int parentIdx = j.parentIndex;
		// Get joint matrix
		MMatrix worldMatrix = j.jointDag.inclusiveMatrix();
		// Calculate Local Matrix
		MMatrix localMatrix;
		if (parentIdx >= 0)
		{
			// Get parent joint
			MDagPath parentDag = m_joints[parentIdx].jointDag;
			localMatrix = worldMatrix * parentDag.inclusiveMatrixInverse();
		}
		else
		{	// Root node of skeleton
			if (params.exportWorldCoords)
				localMatrix = worldMatrix;
			else
				localMatrix = worldMatrix * j.jointDag.exclusiveMatrixInverse();
		}
		// Get relative transformation matrix
		MMatrix relMatrix = localMatrix * j.localMatrix.inverse();
		// Get relative translation
		MVector translation = ((MTransformationMatrix)localMatrix).translation(MSpace::kPostTransform) - 
			((MTransformationMatrix)j.localMatrix).translation(MSpace::kPostTransform);
		if (fabs(translation.x) < PRECISION)
			translation.x = 0;
		if (fabs(translation.y) < PRECISION)
			translation.y = 0;
		if (fabs(translation.z) < PRECISION)
			translation.z = 0;
		// Get relative rotation
		double qx,qy,qz,qw;
		((MTransformationMatrix)relMatrix).getRotationQuaternion(qx,qy,qz,qw);
		MQuaternion rotation(qx,qy,qz,qw);
		MVector axis;
		double theta;
		rotation.getAxisAngle(axis,theta);
		while (theta > Ogre::Math::PI) 
		{ 
			theta -= Ogre::Math::TWO_PI; 
		} 
		while (theta < -Ogre::Math::PI) 
		{ 
			theta += Ogre::Math::TWO_PI; 
		} 
		if (fabs(axis.x) < PRECISION)
			axis.x = 0;
		if (fabs(axis.y) < PRECISION)
			axis.y = 0;
		if (fabs(axis.z) < PRECISION)
			axis.z = 0;
		axis.normalize();
		if (fabs(theta) < PRECISION)
			theta = 0;
		if (axis.length() < 0.5)
		{
			axis.x = 0;
			axis.y = 1;
			axis.z = 0;
			theta = 0;
		}
		// Get relative scale
		double scale[3];
		((MTransformationMatrix)relMatrix).getScale(scale,MSpace::kPostTransform);
		if (fabs(scale[0]) < PRECISION)
			scale[0] = 0;
		if (fabs(scale[1]) < PRECISION)
			scale[1] = 0;
		if (fabs(scale[2]) < PRECISION)
			scale[2] = 0;
		//create keyframe
		skeletonKeyframe key;
		key.time = time;
		key.tx = translation.x * params.lum;
		key.ty = translation.y * params.lum;
		key.tz = translation.z * params.lum;
		key.angle = theta;
		key.axis_x = axis.x;
		key.axis_y = axis.y;
		key.axis_z = axis.z;
		key.sx = scale[0];
		key.sy = scale[1];
		key.sz = scale[2];
		return key;
	}


	// Restore skeleton pose
	void Skeleton::restorePose()
	{
		// save current selection list
		MSelectionList selectionList;
		MGlobal::getActiveSelectionList(selectionList);
		int i;
		for (i=0; i<m_roots.size(); i++)
		{
			MDagPath rootDag = m_joints[m_roots[i]].jointDag;
			// select the root joint dag
			MGlobal::selectByName(rootDag.fullPathName(),MGlobal::kReplaceList);
			// restore pose
			MString cmd = "dagPose -r -g -n \""+ m_restorePose;
			cmd += "\"";
			MGlobal::executeCommand(cmd,true);
		}
		//restore selection list
		MGlobal::setActiveSelectionList(selectionList,MGlobal::kReplaceList);
		//enable constraints, IK, etc...
		MGlobal::executeCommand("doEnableNodeItems true all",true);
	}



	// Get joint list
	std::vector<joint>& Skeleton::getJoints()
	{
		return m_joints;
	}



	// Get animations
	std::vector<Animation>& Skeleton::getAnimations()
	{
		return m_animations;
	}



	// Write to an OGRE binary skeleton
	MStatus Skeleton::writeOgreBinary(ParamList &params)
	{
		MStatus stat;
		// Construct skeleton
		MString name = "mayaExport";
		Ogre::SkeletonPtr pSkeleton = Ogre::SkeletonManager::getSingleton().create(name.asChar(), 
			Ogre::ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME);
		// Create skeleton bones
		stat = createOgreBones(pSkeleton,params);
		if (stat != MS::kSuccess)
		{
			std::cout << "Error writing skeleton binary file\n";
			std::cout.flush();
		}
		// Create skeleton animation
		if (params.exportSkelAnims)
		{
			stat = createOgreSkeletonAnimations(pSkeleton,params);
			if (stat != MS::kSuccess)
			{
				std::cout << "Error writing ogre skeleton animations\n";
				std::cout.flush();
			}
		}
		pSkeleton->setBindingPose();
		// Optimise animations
		pSkeleton->optimiseAllAnimations();
		// Export skeleton binary
		Ogre::SkeletonSerializer serializer;
		serializer.exportSkeleton(pSkeleton.getPointer(),params.skeletonFilename.asChar());
		pSkeleton.setNull();
		// Skeleton successfully exported
		return MS::kSuccess;
	}

	// Write joints to an Ogre skeleton
	MStatus Skeleton::createOgreBones(Ogre::SkeletonPtr pSkeleton,ParamList& params)
	{
		int i;
		// Create the bones
		for (i=0; i<m_joints.size(); i++)
		{
			joint* j = &m_joints[i];
			// Create a new bone
			Ogre::Bone* pBone = pSkeleton->createBone(m_joints[i].name.asChar(), m_joints[i].id);
			// Set bone position (relative to it's parent)
			pBone->setPosition(j->posx,j->posy,j->posz);
			// Set bone orientation (relative to it's parent)
			Ogre::Quaternion orient;
			orient.FromAngleAxis(Ogre::Radian(j->angle),Ogre::Vector3(j->axisx,j->axisy,j->axisz));
			pBone->setOrientation(orient);
			// Set bone scale (relative to it's parent
			pBone->setScale(j->scalex,j->scaley,j->scalez);
		}
		// Create the hierarchy
		for (i=0; i<m_joints.size(); i++)
		{
			int parentIdx = m_joints[i].parentIndex;
			if (parentIdx >= 0)
			{
				// Get the parent joint
				Ogre::Bone* pParent = pSkeleton->getBone(m_joints[parentIdx].id);
				// Get current joint from skeleton
				Ogre::Bone* pBone = pSkeleton->getBone(m_joints[i].id);
				// Place current bone in the parent's child list
				pParent->addChild(pBone);
			}
		}
		return MS::kSuccess;
	}


	// Write skeleton animations to an Ogre skeleton
	MStatus Skeleton::createOgreSkeletonAnimations(Ogre::SkeletonPtr pSkeleton,ParamList& params)
	{
		int i,j,k;
		// Read loaded skeleton animations
		for (i=0; i<m_animations.size(); i++)
		{
			// Create a new animation
			Ogre::Animation* pAnimation = pSkeleton->createAnimation(m_animations[i].m_name.asChar(),
				m_animations[i].m_length);
			// Create tracks for current animation
			for (j=0; j<m_animations[i].m_tracks.size(); j++)
			{
				Track* t = &m_animations[i].m_tracks[j];
				// Create a new track
				Ogre::NodeAnimationTrack* pTrack = pAnimation->createNodeTrack(j,
					pSkeleton->getBone(t->m_bone.asChar()));
				// Create keyframes for current track
				for (k=0; k<t->m_skeletonKeyframes.size(); k++)
				{
					skeletonKeyframe* keyframe = &t->m_skeletonKeyframes[k];
					// Create a new keyframe
					Ogre::TransformKeyFrame* pKeyframe = pTrack->createNodeKeyFrame(keyframe->time);
					// Set translation
					pKeyframe->setTranslate(Ogre::Vector3(keyframe->tx,keyframe->ty,keyframe->tz));
					// Set rotation
					Ogre::Quaternion rot;
					rot.FromAngleAxis(Ogre::Radian(keyframe->angle),
						Ogre::Vector3(keyframe->axis_x,keyframe->axis_y,keyframe->axis_z));
					pKeyframe->setRotation(rot);
					// Set scale
					pKeyframe->setScale(Ogre::Vector3(keyframe->sx,keyframe->sy,keyframe->sz));
				}
			}
		}
		return MS::kSuccess;
	}


};	//end namespace