/*
 * ***** 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) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 * The Original Code is: all of this file.
 *
 * Contributor(s): none yet.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/editors/sculpt_paint/paint_utils.c
 *  \ingroup edsculpt
 */

#include <math.h>
#include <stdlib.h>

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

#include "DNA_scene_types.h"
#include "DNA_brush_types.h"

#include "BLI_math.h"
#include "BLI_utildefines.h"
#include "BLI_listbase.h"
#include "BLI_rect.h"

#include "BLF_translation.h"

#include "BKE_brush.h"
#include "BKE_context.h"
#include "BKE_DerivedMesh.h"
#include "BKE_paint.h"
#include "BKE_report.h"

#include "RNA_access.h"
#include "RNA_define.h"

#include "BIF_gl.h"
#include "BIF_glutil.h"

#include "RE_shader_ext.h"
#include "RE_render_ext.h"

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

#include "BLI_sys_types.h"
#include "ED_mesh.h" /* for face mask functions */

#include "WM_api.h"
#include "WM_types.h"

#include "paint_intern.h"

/* Convert the object-space axis-aligned bounding box (expressed as
 * its minimum and maximum corners) into a screen-space rectangle,
 * returns zero if the result is empty */
bool paint_convert_bb_to_rect(rcti *rect,
                              const float bb_min[3],
                              const float bb_max[3],
                              const ARegion *ar,
                              RegionView3D *rv3d,
                              Object *ob)
{
	float projection_mat[4][4];
	int i, j, k;

	BLI_rcti_init_minmax(rect);

	/* return zero if the bounding box has non-positive volume */
	if (bb_min[0] > bb_max[0] || bb_min[1] > bb_max[1] || bb_min[2] > bb_max[2])
		return 0;

	ED_view3d_ob_project_mat_get(rv3d, ob, projection_mat);

	for (i = 0; i < 2; ++i) {
		for (j = 0; j < 2; ++j) {
			for (k = 0; k < 2; ++k) {
				float vec[3], proj[2];
				int proj_i[2];
				vec[0] = i ? bb_min[0] : bb_max[0];
				vec[1] = j ? bb_min[1] : bb_max[1];
				vec[2] = k ? bb_min[2] : bb_max[2];
				/* convert corner to screen space */
				ED_view3d_project_float_v2_m4(ar, vec, proj, projection_mat);
				/* expand 2D rectangle */

				/* we could project directly to int? */
				proj_i[0] = proj[0];
				proj_i[1] = proj[1];

				BLI_rcti_do_minmax_v(rect, proj_i);
			}
		}
	}

	/* return false if the rectangle has non-positive area */
	return rect->xmin < rect->xmax && rect->ymin < rect->ymax;
}

/* Get four planes in object-space that describe the projection of
 * screen_rect from screen into object-space (essentially converting a
 * 2D screens-space bounding box into four 3D planes) */
void paint_calc_redraw_planes(float planes[4][4],
                              const ARegion *ar,
                              RegionView3D *rv3d,
                              Object *ob,
                              const rcti *screen_rect)
{
	BoundBox bb;
	bglMats mats;
	rcti rect;

	memset(&bb, 0, sizeof(BoundBox));
	view3d_get_transformation(ar, rv3d, ob, &mats);

	/* use some extra space just in case */
	rect = *screen_rect;
	rect.xmin -= 2;
	rect.xmax += 2;
	rect.ymin -= 2;
	rect.ymax += 2;

	ED_view3d_clipping_calc(&bb, planes, &mats, &rect);
	mul_m4_fl(planes, -1.0f);
}

float paint_calc_object_space_radius(ViewContext *vc, const float center[3],
                                     float pixel_radius)
{
	Object *ob = vc->obact;
	float delta[3], scale, loc[3];
	const float mval_f[2] = {pixel_radius, 0.0f};
	float zfac;

	mul_v3_m4v3(loc, ob->obmat, center);

	zfac = ED_view3d_calc_zfac(vc->rv3d, loc, NULL);
	ED_view3d_win_to_delta(vc->ar, mval_f, delta, zfac);

	scale = fabsf(mat4_to_scale(ob->obmat));
	scale = (scale == 0.0f) ? 1.0f : scale;

	return len_v3(delta) / scale;
}

float paint_get_tex_pixel(MTex *mtex, float u, float v, struct ImagePool *pool, int thread)
{
	float intensity, rgba[4];
	float co[3] = {u, v, 0.0f};

	externtex(mtex, co, &intensity,
	          rgba, rgba + 1, rgba + 2, rgba + 3, thread, pool);

	return intensity;
}

void paint_get_tex_pixel_col(MTex *mtex, float u, float v, float rgba[4], struct ImagePool *pool, int thread)
{
	float co[3] = {u, v, 0.0f};
	int hasrgb;
	float intensity;

	hasrgb = externtex(mtex, co, &intensity,
	                   rgba, rgba + 1, rgba + 2, rgba + 3, thread, pool);
	if (!hasrgb) {
		rgba[0] = intensity;
		rgba[1] = intensity;
		rgba[2] = intensity;
		rgba[3] = 1.0f;
	}
	CLAMP(rgba[0], 0.0f, 1.0f);
	CLAMP(rgba[1], 0.0f, 1.0f);
	CLAMP(rgba[2], 0.0f, 1.0f);
	CLAMP(rgba[3], 0.0f, 1.0f);
}

/* Uses symm to selectively flip any axis of a coordinate. */
void flip_v3_v3(float out[3], const float in[3], const char symm)
{
	if (symm & PAINT_SYMM_X)
		out[0] = -in[0];
	else
		out[0] = in[0];
	if (symm & PAINT_SYMM_Y)
		out[1] = -in[1];
	else
		out[1] = in[1];
	if (symm & PAINT_SYMM_Z)
		out[2] = -in[2];
	else
		out[2] = in[2];
}

/* used for both 3d view and image window */
void paint_sample_color(const bContext *C, ARegion *ar, int x, int y)    /* frontbuf */
{
	Brush *br = BKE_paint_brush(BKE_paint_get_active_from_context(C));
	unsigned int col;
	char *cp;

	CLAMP(x, 0, ar->winx);
	CLAMP(y, 0, ar->winy);
	
	glReadBuffer(GL_FRONT);
	glReadPixels(x + ar->winrct.xmin, y + ar->winrct.ymin, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &col);
	glReadBuffer(GL_BACK);

	cp = (char *)&col;
	
	if (br) {
		br->rgb[0] = cp[0] / 255.0f;
		br->rgb[1] = cp[1] / 255.0f;
		br->rgb[2] = cp[2] / 255.0f;
	}
}

static int brush_curve_preset_exec(bContext *C, wmOperator *op)
{
	Brush *br = BKE_paint_brush(BKE_paint_get_active_from_context(C));

	if (br) {
		Scene *scene = CTX_data_scene(C);
		BKE_brush_curve_preset(br, RNA_enum_get(op->ptr, "shape"));
		BKE_paint_invalidate_cursor_overlay(scene, br->curve);
	}

	return OPERATOR_FINISHED;
}

static int brush_curve_preset_poll(bContext *C)
{
	Brush *br = BKE_paint_brush(BKE_paint_get_active_from_context(C));

	return br && br->curve;
}

void BRUSH_OT_curve_preset(wmOperatorType *ot)
{
	PropertyRNA *prop;
	static EnumPropertyItem prop_shape_items[] = {
		{CURVE_PRESET_SHARP, "SHARP", 0, "Sharp", ""},
		{CURVE_PRESET_SMOOTH, "SMOOTH", 0, "Smooth", ""},
		{CURVE_PRESET_MAX, "MAX", 0, "Max", ""},
		{CURVE_PRESET_LINE, "LINE", 0, "Line", ""},
		{CURVE_PRESET_ROUND, "ROUND", 0, "Round", ""},
		{CURVE_PRESET_ROOT, "ROOT", 0, "Root", ""},
		{0, NULL, 0, NULL, NULL}};

	ot->name = "Preset";
	ot->description = "Set brush shape";
	ot->idname = "BRUSH_OT_curve_preset";

	ot->exec = brush_curve_preset_exec;
	ot->poll = brush_curve_preset_poll;

	prop = RNA_def_enum(ot->srna, "shape", prop_shape_items, CURVE_PRESET_SMOOTH, "Mode", "");
	RNA_def_property_translation_context(prop, BLF_I18NCONTEXT_ID_CURVE); /* Abusing id_curve :/ */
}


/* face-select ops */
static int paint_select_linked_exec(bContext *C, wmOperator *UNUSED(op))
{
	paintface_select_linked(C, CTX_data_active_object(C), NULL, true);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}

void PAINT_OT_face_select_linked(wmOperatorType *ot)
{
	ot->name = "Select Linked";
	ot->description = "Select linked faces";
	ot->idname = "PAINT_OT_face_select_linked";

	ot->exec = paint_select_linked_exec;
	ot->poll = facemask_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
}

static int paint_select_linked_pick_invoke(bContext *C, wmOperator *op, const wmEvent *event)
{
	const bool select = !RNA_boolean_get(op->ptr, "deselect");
	view3d_operator_needs_opengl(C);
	paintface_select_linked(C, CTX_data_active_object(C), event->mval, select);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}

void PAINT_OT_face_select_linked_pick(wmOperatorType *ot)
{
	ot->name = "Select Linked Pick";
	ot->description = "Select linked faces under the cursor";
	ot->idname = "PAINT_OT_face_select_linked_pick";

	ot->invoke = paint_select_linked_pick_invoke;
	ot->poll = facemask_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;

	RNA_def_boolean(ot->srna, "deselect", 0, "Deselect", "Deselect rather than select items");
}


static int face_select_all_exec(bContext *C, wmOperator *op)
{
	Object *ob = CTX_data_active_object(C);
	paintface_deselect_all_visible(ob, RNA_enum_get(op->ptr, "action"), true);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}


void PAINT_OT_face_select_all(wmOperatorType *ot)
{
	ot->name = "(De)select All";
	ot->description = "Change selection for all faces";
	ot->idname = "PAINT_OT_face_select_all";

	ot->exec = face_select_all_exec;
	ot->poll = facemask_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;

	WM_operator_properties_select_all(ot);
}


static int vert_select_all_exec(bContext *C, wmOperator *op)
{
	Object *ob = CTX_data_active_object(C);
	paintvert_deselect_all_visible(ob, RNA_enum_get(op->ptr, "action"), true);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}


void PAINT_OT_vert_select_all(wmOperatorType *ot)
{
	ot->name = "(De)select All";
	ot->description = "Change selection for all vertices";
	ot->idname = "PAINT_OT_vert_select_all";

	ot->exec = vert_select_all_exec;
	ot->poll = vert_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;

	WM_operator_properties_select_all(ot);
}


static int vert_select_ungrouped_exec(bContext *C, wmOperator *op)
{
	Object *ob = CTX_data_active_object(C);
	Mesh *me = ob->data;

	if (BLI_listbase_is_empty(&ob->defbase) || (me->dvert == NULL)) {
		BKE_report(op->reports, RPT_ERROR, "No weights/vertex groups on object");
		return OPERATOR_CANCELLED;
	}

	paintvert_select_ungrouped(ob, RNA_boolean_get(op->ptr, "extend"), true);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}

void PAINT_OT_vert_select_ungrouped(wmOperatorType *ot)
{
	/* identifiers */
	ot->name = "Select Ungrouped";
	ot->idname = "PAINT_OT_vert_select_ungrouped";
	ot->description = "Select vertices without a group";

	/* api callbacks */
	ot->exec = vert_select_ungrouped_exec;
	ot->poll = vert_paint_poll;

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

	RNA_def_boolean(ot->srna, "extend", false, "Extend", "Extend the selection");
}

static int face_select_hide_exec(bContext *C, wmOperator *op)
{
	const bool unselected = RNA_boolean_get(op->ptr, "unselected");
	Object *ob = CTX_data_active_object(C);
	paintface_hide(ob, unselected);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}

void PAINT_OT_face_select_hide(wmOperatorType *ot)
{
	ot->name = "Face Select Hide";
	ot->description = "Hide selected faces";
	ot->idname = "PAINT_OT_face_select_hide";

	ot->exec = face_select_hide_exec;
	ot->poll = facemask_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;

	RNA_def_boolean(ot->srna, "unselected", 0, "Unselected", "Hide unselected rather than selected objects");
}

static int face_select_reveal_exec(bContext *C, wmOperator *UNUSED(op))
{
	Object *ob = CTX_data_active_object(C);
	paintface_reveal(ob);
	ED_region_tag_redraw(CTX_wm_region(C));
	return OPERATOR_FINISHED;
}

void PAINT_OT_face_select_reveal(wmOperatorType *ot)
{
	ot->name = "Face Select Reveal";
	ot->description = "Reveal hidden faces";
	ot->idname = "PAINT_OT_face_select_reveal";

	ot->exec = face_select_reveal_exec;
	ot->poll = facemask_paint_poll;

	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;

	RNA_def_boolean(ot->srna, "unselected", 0, "Unselected", "Hide unselected rather than selected objects");
}