/*
 * ***** 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) 2013 Blender Foundation.
 * All rights reserved.
 *
 *
 * Contributor(s): Campbell Barton
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/editors/mesh/editmesh_knife_project.c
 *  \ingroup edmesh
 */

#include "DNA_curve_types.h"
#include "DNA_object_types.h"

#include "BLI_math.h"
#include "BLI_linklist.h"
#include "BLI_listbase.h"

#include "BKE_mesh.h"
#include "BKE_context.h"
#include "BKE_curve.h"
#include "BKE_cdderivedmesh.h"
#include "BKE_editmesh.h"
#include "BKE_report.h"

#include "MEM_guardedalloc.h"

#include "WM_types.h"

#include "ED_mesh.h"
#include "ED_screen.h"
#include "ED_view3d.h"

#include "mesh_intern.h"  /* own include */


static LinkNode *knifeproject_poly_from_object(ARegion *ar, Scene *scene, Object *ob, LinkNode *polys)
{
	DerivedMesh *dm;
	bool dm_needsFree;

	if (ob->type == OB_MESH || ob->derivedFinal) {
		dm = ob->derivedFinal ? ob->derivedFinal : mesh_get_derived_final(scene, ob, CD_MASK_BAREMESH);
		dm_needsFree = false;
	}
	else if (ELEM3(ob->type, OB_FONT, OB_CURVE, OB_SURF)) {
		dm = CDDM_from_curve(ob);
		dm_needsFree = true;
	}
	else {
		dm = NULL;
	}

	if (dm) {
		ListBase nurbslist = {NULL, NULL};
		float projmat[4][4];

		BKE_mesh_to_curve_nurblist(dm, &nurbslist, 0);  /* wire */
		BKE_mesh_to_curve_nurblist(dm, &nurbslist, 1);  /* boundary */

		ED_view3d_ob_project_mat_get(ar->regiondata, ob, projmat);

		if (nurbslist.first) {
			Nurb *nu;
			for (nu = nurbslist.first; nu; nu = nu->next) {
				if (nu->bp) {
					int a;
					BPoint *bp;
					bool is_cyclic = (nu->flagu & CU_NURB_CYCLIC) != 0;
					float (*mval)[2] = MEM_mallocN(sizeof(*mval) * (nu->pntsu + is_cyclic), __func__);

					for (bp = nu->bp, a = 0; a < nu->pntsu; a++, bp++) {
						ED_view3d_project_float_v2_m4(ar, bp->vec, mval[a], projmat);
					}
					if (is_cyclic) {
						copy_v2_v2(mval[a], mval[0]);
					}

					BLI_linklist_prepend(&polys, mval);
				}
			}
		}

		BKE_nurbList_free(&nurbslist);

		if (dm_needsFree) {
			dm->release(dm);
		}
	}


	return polys;
}

static int knifeproject_exec(bContext *C, wmOperator *op)
{
	ARegion *ar = CTX_wm_region(C);
	Scene *scene = CTX_data_scene(C);
	Object *obedit = CTX_data_edit_object(C);
	BMEditMesh *em = BKE_editmesh_from_object(obedit);

	LinkNode *polys = NULL;

	CTX_DATA_BEGIN (C, Object *, ob, selected_objects)
	{
		if (ob != obedit) {
			polys = knifeproject_poly_from_object(ar, scene, ob, polys);
		}
	}
	CTX_DATA_END;

	if (polys) {
		EDBM_mesh_knife(C, polys, true);

		/* select only tagged faces */
		BM_mesh_elem_hflag_disable_all(em->bm, BM_VERT | BM_EDGE | BM_FACE, BM_ELEM_SELECT, false);

		/* not essential, but switch out of vertex mode since the
		 * selected regions wont be nicely isolated after flushing.
		 * note: call after de-select to avoid selection flushing */
		EDBM_selectmode_disable(scene, em, SCE_SELECT_VERTEX, SCE_SELECT_EDGE);

		BM_mesh_elem_hflag_enable_test(em->bm, BM_FACE, BM_ELEM_SELECT, true, BM_ELEM_TAG);

		BM_mesh_select_mode_flush(em->bm);

		BLI_linklist_freeN(polys);

		return OPERATOR_FINISHED;
	}
	else {
		BKE_report(op->reports, RPT_ERROR, "No other selected objects found to use for projection");
		return OPERATOR_CANCELLED;
	}
}

void MESH_OT_knife_project(wmOperatorType *ot)
{
	/* description */
	ot->name = "Knife Project";
	ot->idname = "MESH_OT_knife_project";
	ot->description = "Use other objects outlines & boundaries to project knife cuts";

	/* callbacks */
	ot->exec = knifeproject_exec;
	ot->poll = ED_operator_editmesh_view3d;

	/* flags */
	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO | OPTYPE_BLOCKING;
}
