/*
 * ***** 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 *****
 *
 */

/** \file blender/modifiers/intern/MOD_cloth.c
 *  \ingroup modifiers
 */

#include <string.h>

#include "DNA_cloth_types.h"
#include "DNA_key_types.h"
#include "DNA_scene_types.h"
#include "DNA_object_types.h"

#include "MEM_guardedalloc.h"

#include "BLI_utildefines.h"


#include "BKE_cloth.h"
#include "BKE_cdderivedmesh.h"
#include "BKE_global.h"
#include "BKE_key.h"
#include "BKE_modifier.h"
#include "BKE_pointcache.h"

#include "depsgraph_private.h"

#include "MOD_util.h"

static void initData(ModifierData *md) 
{
	ClothModifierData *clmd = (ClothModifierData *) md;
	
	clmd->sim_parms = MEM_callocN(sizeof(ClothSimSettings), "cloth sim parms");
	clmd->coll_parms = MEM_callocN(sizeof(ClothCollSettings), "cloth coll parms");
	clmd->point_cache = BKE_ptcache_add(&clmd->ptcaches);
	
	/* check for alloc failing */
	if (!clmd->sim_parms || !clmd->coll_parms || !clmd->point_cache)
		return;
	
	cloth_init(clmd);
}

static void deformVerts(ModifierData *md, Object *ob, DerivedMesh *derivedData, float (*vertexCos)[3],
                        int numVerts, ModifierApplyFlag UNUSED(flag))
{
	DerivedMesh *dm;
	ClothModifierData *clmd = (ClothModifierData *) md;
	
	/* check for alloc failing */
	if (!clmd->sim_parms || !clmd->coll_parms) {
		initData(md);

		if (!clmd->sim_parms || !clmd->coll_parms)
			return;
	}

	dm = get_dm(ob, NULL, derivedData, NULL, false, false);
	if (dm == derivedData)
		dm = CDDM_copy(dm);

	/* TODO(sergey): For now it actually duplicates logic from DerivedMesh.c
	 * and needs some more generic solution. But starting experimenting with
	 * this so close to the release is not that nice..
	 *
	 * Also hopefully new cloth system will arrive soon..
	 */
	if (derivedData == NULL && clmd->sim_parms->shapekey_rest) {
		KeyBlock *kb = BKE_keyblock_from_key(BKE_key_from_object(ob),
		                                     clmd->sim_parms->shapekey_rest);
		if (kb->data != NULL) {
			float (*layerorco)[3];
			if (!(layerorco = DM_get_vert_data_layer(dm, CD_CLOTH_ORCO))) {
				DM_add_vert_layer(dm, CD_CLOTH_ORCO, CD_CALLOC, NULL);
				layerorco = DM_get_vert_data_layer(dm, CD_CLOTH_ORCO);
			}

			memcpy(layerorco, kb->data, sizeof(float) * 3 * numVerts);
		}
	}

	CDDM_apply_vert_coords(dm, vertexCos);

	DM_ensure_tessface(dm); /* BMESH - UNTIL MODIFIER IS UPDATED FOR MPoly */

	clothModifier_do(clmd, md->scene, ob, dm, vertexCos);

	dm->release(dm);
}

static void updateDepgraph(ModifierData *md, DagForest *forest, Scene *scene, Object *ob, DagNode *obNode)
{
	ClothModifierData *clmd = (ClothModifierData *) md;
	
	Base *base;
	
	if (clmd) {
		for (base = scene->base.first; base; base = base->next) {
			Object *ob1 = base->object;
			if (ob1 != ob) {
				CollisionModifierData *coll_clmd = (CollisionModifierData *)modifiers_findByType(ob1, eModifierType_Collision);
				if (coll_clmd) {
					DagNode *curNode = dag_get_node(forest, ob1);
					dag_add_relation(forest, curNode, obNode, DAG_RL_DATA_DATA | DAG_RL_OB_DATA, "Cloth Collision");
				}
			}
		}
	}
}

static CustomDataMask requiredDataMask(Object *UNUSED(ob), ModifierData *md)
{
	CustomDataMask dataMask = 0;
	ClothModifierData *clmd = (ClothModifierData *)md;

	if (cloth_uses_vgroup(clmd))
		dataMask |= CD_MASK_MDEFORMVERT;

	if (clmd->sim_parms->shapekey_rest != 0)
		dataMask |= CD_MASK_CLOTH_ORCO;

	return dataMask;
}

static void copyData(ModifierData *md, ModifierData *target)
{
	ClothModifierData *clmd = (ClothModifierData *) md;
	ClothModifierData *tclmd = (ClothModifierData *) target;

	if (tclmd->sim_parms) {
		if (tclmd->sim_parms->effector_weights)
			MEM_freeN(tclmd->sim_parms->effector_weights);
		MEM_freeN(tclmd->sim_parms);
	}

	if (tclmd->coll_parms)
		MEM_freeN(tclmd->coll_parms);
	
	BKE_ptcache_free_list(&tclmd->ptcaches);
	tclmd->point_cache = NULL;

	tclmd->sim_parms = MEM_dupallocN(clmd->sim_parms);
	if (clmd->sim_parms->effector_weights)
		tclmd->sim_parms->effector_weights = MEM_dupallocN(clmd->sim_parms->effector_weights);
	tclmd->coll_parms = MEM_dupallocN(clmd->coll_parms);
	tclmd->point_cache = BKE_ptcache_add(&tclmd->ptcaches);
	tclmd->point_cache->step = 1;
	tclmd->clothObject = NULL;
}

static bool dependsOnTime(ModifierData *UNUSED(md))
{
	return true;
}

static void freeData(ModifierData *md)
{
	ClothModifierData *clmd = (ClothModifierData *) md;
	
	if (clmd) {
		if (G.debug_value > 0)
			printf("clothModifier_freeData\n");
		
		cloth_free_modifier_extern(clmd);
		
		if (clmd->sim_parms) {
			if (clmd->sim_parms->effector_weights)
				MEM_freeN(clmd->sim_parms->effector_weights);
			MEM_freeN(clmd->sim_parms);
		}
		if (clmd->coll_parms)
			MEM_freeN(clmd->coll_parms);
		
		BKE_ptcache_free_list(&clmd->ptcaches);
		clmd->point_cache = NULL;
	}
}

static void foreachIDLink(ModifierData *md, Object *ob,
                          IDWalkFunc walk, void *userData)
{
	ClothModifierData *clmd = (ClothModifierData *) md;

	if (clmd->coll_parms) {
		walk(userData, ob, (ID **)&clmd->coll_parms->group);
	}

	if (clmd->sim_parms && clmd->sim_parms->effector_weights) {
		walk(userData, ob, (ID **)&clmd->sim_parms->effector_weights->group);
	}
}

ModifierTypeInfo modifierType_Cloth = {
	/* name */              "Cloth",
	/* structName */        "ClothModifierData",
	/* structSize */        sizeof(ClothModifierData),
	/* type */              eModifierTypeType_OnlyDeform,
	/* flags */             eModifierTypeFlag_AcceptsMesh |
	                        eModifierTypeFlag_UsesPointCache |
	                        eModifierTypeFlag_Single,

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