/*
* $Id$
*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software  Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2005 by the Blender Foundation.
* All rights reserved.
*
* Contributor(s): Daniel Dunbar
*                 Ton Roosendaal,
*                 Ben Batt,
*                 Brecht Van Lommel,
*                 Campbell Barton
*
* ***** END GPL LICENSE BLOCK *****
*
*/

#include "DNA_meshdata_types.h"
#include "DNA_object_types.h"

#include "BLI_math.h"

#include "BKE_cdderivedmesh.h"
#include "BKE_mesh.h"
#include "BKE_modifier.h"
#include "BKE_deform.h"
#include "BKE_utildefines.h"

#include "MEM_guardedalloc.h"
#include "depsgraph_private.h"

static void initData(ModifierData *md)
{
	MirrorModifierData *mmd = (MirrorModifierData*) md;

	mmd->flag |= (MOD_MIR_AXIS_X | MOD_MIR_VGROUP);
	mmd->tolerance = 0.001;
	mmd->mirror_ob = NULL;
}

static void copyData(ModifierData *md, ModifierData *target)
{
	MirrorModifierData *mmd = (MirrorModifierData*) md;
	MirrorModifierData *tmmd = (MirrorModifierData*) target;

	tmmd->axis = mmd->axis;
	tmmd->flag = mmd->flag;
	tmmd->tolerance = mmd->tolerance;
	tmmd->mirror_ob = mmd->mirror_ob;;
}

static void foreachObjectLink(
						 ModifierData *md, Object *ob,
	  void (*walk)(void *userData, Object *ob, Object **obpoin),
		 void *userData)
{
	MirrorModifierData *mmd = (MirrorModifierData*) md;

	walk(userData, ob, &mmd->mirror_ob);
}

static void updateDepgraph(ModifierData *md, DagForest *forest, struct Scene *scene,
					  Object *ob, DagNode *obNode)
{
	MirrorModifierData *mmd = (MirrorModifierData*) md;

	if(mmd->mirror_ob) {
		DagNode *latNode = dag_get_node(forest, mmd->mirror_ob);

		dag_add_relation(forest, latNode, obNode,
				 DAG_RL_DATA_DATA | DAG_RL_OB_DATA, "Mirror Modifier");
	}
}

static DerivedMesh *doMirrorOnAxis(MirrorModifierData *mmd,
		Object *ob,
		DerivedMesh *dm,
		int initFlags,
		int axis)
{
	int i;
	float tolerance = mmd->tolerance;
	DerivedMesh *result;
	int numVerts, numEdges, numFaces;
	int maxVerts = dm->getNumVerts(dm);
	int maxEdges = dm->getNumEdges(dm);
	int maxFaces = dm->getNumFaces(dm);
	int *flip_map= NULL;
	int do_vgroup_mirr= (mmd->flag & MOD_MIR_VGROUP);
	int (*indexMap)[2];
	float mtx[4][4], imtx[4][4];

	numVerts = numEdges = numFaces = 0;

	indexMap = MEM_mallocN(sizeof(*indexMap) * maxVerts, "indexmap");

	result = CDDM_from_template(dm, maxVerts * 2, maxEdges * 2, maxFaces * 2);


	if (do_vgroup_mirr) {
		flip_map= defgroup_flip_map(ob, 0);
		if(flip_map == NULL)
			do_vgroup_mirr= 0;
	}

	if (mmd->mirror_ob) {
		float obinv[4][4];
		
		invert_m4_m4(obinv, mmd->mirror_ob->obmat);
		mul_m4_m4m4(mtx, ob->obmat, obinv);
		invert_m4_m4(imtx, mtx);
	}

	for(i = 0; i < maxVerts; i++) {
		MVert inMV;
		MVert *mv = CDDM_get_vert(result, numVerts);
		int isShared;
		float co[3];
		
		dm->getVert(dm, i, &inMV);
		
		copy_v3_v3(co, inMV.co);
		
		if (mmd->mirror_ob) {
			mul_m4_v3(mtx, co);
		}
		isShared = ABS(co[axis])<=tolerance;
		
		/* Because the topology result (# of vertices) must be the same if
		* the mesh data is overridden by vertex cos, have to calc sharedness
		* based on original coordinates. This is why we test before copy.
		*/
		DM_copy_vert_data(dm, result, i, numVerts, 1);
		*mv = inMV;
		numVerts++;
		
		indexMap[i][0] = numVerts - 1;
		indexMap[i][1] = !isShared;
		
		if(isShared) {
			co[axis] = 0;
			if (mmd->mirror_ob) {
				mul_m4_v3(imtx, co);
			}
			copy_v3_v3(mv->co, co);
			
			mv->flag |= ME_VERT_MERGED;
		} else {
			MVert *mv2 = CDDM_get_vert(result, numVerts);
			
			DM_copy_vert_data(dm, result, i, numVerts, 1);
			*mv2 = *mv;
			
			co[axis] = -co[axis];
			if (mmd->mirror_ob) {
				mul_m4_v3(imtx, co);
			}
			copy_v3_v3(mv2->co, co);
			
			if (do_vgroup_mirr) {
				MDeformVert *dvert= DM_get_vert_data(result, numVerts, CD_MDEFORMVERT);
				if(dvert) {
					defvert_flip(dvert, flip_map);
				}
			}

			numVerts++;
		}
	}

	for(i = 0; i < maxEdges; i++) {
		MEdge inMED;
		MEdge *med = CDDM_get_edge(result, numEdges);
		
		dm->getEdge(dm, i, &inMED);
		
		DM_copy_edge_data(dm, result, i, numEdges, 1);
		*med = inMED;
		numEdges++;
		
		med->v1 = indexMap[inMED.v1][0];
		med->v2 = indexMap[inMED.v2][0];
		if(initFlags)
			med->flag |= ME_EDGEDRAW | ME_EDGERENDER;
		
		if(indexMap[inMED.v1][1] || indexMap[inMED.v2][1]) {
			MEdge *med2 = CDDM_get_edge(result, numEdges);
			
			DM_copy_edge_data(dm, result, i, numEdges, 1);
			*med2 = *med;
			numEdges++;
			
			med2->v1 += indexMap[inMED.v1][1];
			med2->v2 += indexMap[inMED.v2][1];
		}
	}

	for(i = 0; i < maxFaces; i++) {
		MFace inMF;
		MFace *mf = CDDM_get_face(result, numFaces);
		
		dm->getFace(dm, i, &inMF);
		
		DM_copy_face_data(dm, result, i, numFaces, 1);
		*mf = inMF;
		numFaces++;
		
		mf->v1 = indexMap[inMF.v1][0];
		mf->v2 = indexMap[inMF.v2][0];
		mf->v3 = indexMap[inMF.v3][0];
		mf->v4 = indexMap[inMF.v4][0];
		
		if(indexMap[inMF.v1][1]
				 || indexMap[inMF.v2][1]
				 || indexMap[inMF.v3][1]
				 || (mf->v4 && indexMap[inMF.v4][1])) {
			MFace *mf2 = CDDM_get_face(result, numFaces);
			static int corner_indices[4] = {2, 1, 0, 3};
			
			DM_copy_face_data(dm, result, i, numFaces, 1);
			*mf2 = *mf;
			
			mf2->v1 += indexMap[inMF.v1][1];
			mf2->v2 += indexMap[inMF.v2][1];
			mf2->v3 += indexMap[inMF.v3][1];
			if(inMF.v4) mf2->v4 += indexMap[inMF.v4][1];
			
			/* mirror UVs if enabled */
			if(mmd->flag & (MOD_MIR_MIRROR_U | MOD_MIR_MIRROR_V)) {
				MTFace *tf = result->getFaceData(result, numFaces, CD_MTFACE);
				if(tf) {
					int j;
					for(j = 0; j < 4; ++j) {
						if(mmd->flag & MOD_MIR_MIRROR_U)
							tf->uv[j][0] = 1.0f - tf->uv[j][0];
						if(mmd->flag & MOD_MIR_MIRROR_V)
							tf->uv[j][1] = 1.0f - tf->uv[j][1];
					}
				}
			}
			
			/* Flip face normal */
			SWAP(int, mf2->v1, mf2->v3);
			DM_swap_face_data(result, numFaces, corner_indices);
			
			test_index_face(mf2, &result->faceData, numFaces, inMF.v4?4:3);
			numFaces++;
		}
	}

	if (flip_map) MEM_freeN(flip_map);

	MEM_freeN(indexMap);

	CDDM_lower_num_verts(result, numVerts);
	CDDM_lower_num_edges(result, numEdges);
	CDDM_lower_num_faces(result, numFaces);

	return result;
}

static DerivedMesh *mirrorModifier__doMirror(MirrorModifierData *mmd,
						Object *ob, DerivedMesh *dm,
						int initFlags)
{
	DerivedMesh *result = dm;

	/* check which axes have been toggled and mirror accordingly */
	if(mmd->flag & MOD_MIR_AXIS_X) {
		result = doMirrorOnAxis(mmd, ob, result, initFlags, 0);
	}
	if(mmd->flag & MOD_MIR_AXIS_Y) {
		DerivedMesh *tmp = result;
		result = doMirrorOnAxis(mmd, ob, result, initFlags, 1);
		if(tmp != dm) tmp->release(tmp); /* free intermediate results */
	}
	if(mmd->flag & MOD_MIR_AXIS_Z) {
		DerivedMesh *tmp = result;
		result = doMirrorOnAxis(mmd, ob, result, initFlags, 2);
		if(tmp != dm) tmp->release(tmp); /* free intermediate results */
	}

	return result;
}

static DerivedMesh *applyModifier(
		ModifierData *md, Object *ob, DerivedMesh *derivedData,
  int useRenderParams, int isFinalCalc)
{
	DerivedMesh *result;
	MirrorModifierData *mmd = (MirrorModifierData*) md;

	result = mirrorModifier__doMirror(mmd, ob, derivedData, 0);

	if(result != derivedData)
		CDDM_calc_normals(result);
	
	return result;
}

static DerivedMesh *applyModifierEM(
		ModifierData *md, Object *ob, struct EditMesh *editData,
  DerivedMesh *derivedData)
{
	return applyModifier(md, ob, derivedData, 0, 1);
}


ModifierTypeInfo modifierType_Mirror = {
	/* name */              "Mirror",
	/* structName */        "MirrorModifierData",
	/* structSize */        sizeof(MirrorModifierData),
	/* type */              eModifierTypeType_Constructive,
	/* flags */             eModifierTypeFlag_AcceptsMesh
							| eModifierTypeFlag_SupportsMapping
							| eModifierTypeFlag_SupportsEditmode
							| eModifierTypeFlag_EnableInEditmode
							| eModifierTypeFlag_AcceptsCVs,

	/* copyData */          copyData,
	/* deformVerts */       0,
	/* deformVertsEM */     0,
	/* deformMatricesEM */  0,
	/* applyModifier */     applyModifier,
	/* applyModifierEM */   applyModifierEM,
	/* initData */          initData,
	/* requiredDataMask */  0,
	/* freeData */          0,
	/* isDisabled */        0,
	/* updateDepgraph */    updateDepgraph,
	/* dependsOnTime */     0,
	/* dependsOnNormals */	0,
	/* foreachObjectLink */ foreachObjectLink,
	/* foreachIDLink */     0,
};