/*
 * ***** 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) 2011 Blender Foundation.
 * All rights reserved.
 *
 *
 * Contributor(s): Blender Foundation,
 *                 Sergey Sharybin
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/editors/space_clip/clip_graph_draw.c
 *  \ingroup spclip
 */

#include "DNA_movieclip_types.h"
#include "DNA_scene_types.h"

#include "BLI_utildefines.h"
#include "BLI_math.h"

#include "BKE_context.h"
#include "BKE_movieclip.h"
#include "BKE_tracking.h"

#include "ED_screen.h"
#include "ED_clip.h"

#include "GPU_immediate.h"
#include "GPU_immediate_util.h"
#include "GPU_matrix.h"
#include "GPU_state.h"

#include "WM_types.h"

#include "UI_interface.h"
#include "UI_resources.h"
#include "UI_view2d.h"


#include "clip_intern.h"    // own include

typedef struct TrackMotionCurveUserData {
	MovieTrackingTrack *act_track;
	bool sel;
	float xscale, yscale, hsize;
	unsigned int pos;
} TrackMotionCurveUserData;

static void tracking_segment_point_cb(void *userdata, MovieTrackingTrack *UNUSED(track),
                                      MovieTrackingMarker *UNUSED(marker), int UNUSED(coord),
                                      int scene_framenr, float val)
{
	TrackMotionCurveUserData *data = (TrackMotionCurveUserData *) userdata;

	immVertex2f(data->pos, scene_framenr, val);
}

static void tracking_segment_start_cb(void *userdata, MovieTrackingTrack *track, int coord, bool is_point)
{
	TrackMotionCurveUserData *data = (TrackMotionCurveUserData *) userdata;
	float col[4] = {0.0f, 0.0f, 0.0f, 0.0f};

	col[coord] = 1.0f;

	if (track == data->act_track) {
		col[3] = 1.0f;
		GPU_line_width(2.0f);
	}
	else {
		col[3] = 0.5f;
		GPU_line_width(1.0f);
	}

	immUniformColor4fv(col);

	if (is_point) {
		immBeginAtMost(GPU_PRIM_POINTS, 1);
	}
	else {
		/* Graph can be composed of smaller segments, if any marker is disabled */
		immBeginAtMost(GPU_PRIM_LINE_STRIP, track->markersnr);
	}
}

static void tracking_segment_end_cb(void *UNUSED(userdata), int UNUSED(coord))
{
	immEnd();
}

static void tracking_segment_knot_cb(void *userdata, MovieTrackingTrack *track,
                                     MovieTrackingMarker *marker, int coord, int scene_framenr, float val)
{
	TrackMotionCurveUserData *data = (TrackMotionCurveUserData *) userdata;
	int sel = 0, sel_flag;

	if (track != data->act_track)
		return;

	sel_flag = coord == 0 ? MARKER_GRAPH_SEL_X : MARKER_GRAPH_SEL_Y;
	sel = (marker->flag & sel_flag) ? 1 : 0;

	if (sel == data->sel) {
		immUniformThemeColor(sel ? TH_HANDLE_VERTEX_SELECT : TH_HANDLE_VERTEX);

		GPU_matrix_push();
		GPU_matrix_translate_2f(scene_framenr, val);
		GPU_matrix_scale_2f(1.0f / data->xscale * data->hsize, 1.0f / data->yscale * data->hsize);

		imm_draw_circle_wire_2d(data->pos, 0, 0, 0.7, 8);

		GPU_matrix_pop();
	}
}

static void draw_tracks_motion_curves(View2D *v2d, SpaceClip *sc, unsigned int pos)
{
	MovieClip *clip = ED_space_clip_get_clip(sc);
	MovieTracking *tracking = &clip->tracking;
	MovieTrackingTrack *act_track = BKE_tracking_track_get_active(tracking);
	int width, height;
	TrackMotionCurveUserData userdata;

	BKE_movieclip_get_size(clip, &sc->user, &width, &height);

	if (!width || !height)
		return;

	/* non-selected knot handles */
	userdata.hsize = UI_GetThemeValuef(TH_HANDLE_VERTEX_SIZE);
	userdata.sel = false;
	userdata.act_track = act_track;
	userdata.pos = pos;
	UI_view2d_scale_get(v2d, &userdata.xscale, &userdata.yscale);
	clip_graph_tracking_values_iterate(sc,
	                                   (sc->flag & SC_SHOW_GRAPH_SEL_ONLY) != 0,
	                                   (sc->flag & SC_SHOW_GRAPH_HIDDEN) != 0,
	                                   &userdata, tracking_segment_knot_cb, NULL, NULL);
	/* draw graph lines */
	GPU_blend(true);
	clip_graph_tracking_values_iterate(sc,
	                                   (sc->flag & SC_SHOW_GRAPH_SEL_ONLY) != 0,
	                                   (sc->flag & SC_SHOW_GRAPH_HIDDEN) != 0,
	                                   &userdata, tracking_segment_point_cb, tracking_segment_start_cb,
	                                   tracking_segment_end_cb);
	GPU_blend(false);

	/* selected knot handles on top of curves */
	userdata.sel = true;
	clip_graph_tracking_values_iterate(sc,
	                                   (sc->flag & SC_SHOW_GRAPH_SEL_ONLY) != 0,
	                                   (sc->flag & SC_SHOW_GRAPH_HIDDEN) != 0,
	                                   &userdata, tracking_segment_knot_cb, NULL, NULL);
}

typedef struct TrackErrorCurveUserData {
	MovieClip *clip;
	MovieTracking *tracking;
	MovieTrackingObject *tracking_object;
	MovieTrackingTrack *active_track;
	bool matrix_initialized;
	int matrix_frame;
	float projection_matrix[4][4];
	int width, height;
	float aspy;
	unsigned int pos;
} TrackErrorCurveUserData;

static void tracking_error_segment_point_cb(void *userdata,
                                            MovieTrackingTrack *track, MovieTrackingMarker *marker,
                                            int coord, int scene_framenr, float UNUSED(value))
{
	if (coord == 1) {
		TrackErrorCurveUserData *data = (TrackErrorCurveUserData *) userdata;
		float reprojected_position[4], bundle_position[4], marker_position[2], delta[2];
		float reprojection_error;
		float weight = BKE_tracking_track_get_weight_for_marker(data->clip, track, marker);

		if (!data->matrix_initialized || data->matrix_frame != scene_framenr) {
			BKE_tracking_get_projection_matrix(data->tracking, data->tracking_object,
			                                   scene_framenr, data->width, data->height,
			                                   data->projection_matrix);
		}

		copy_v3_v3(bundle_position, track->bundle_pos);
		bundle_position[3] = 1;

		mul_v4_m4v4(reprojected_position, data->projection_matrix, bundle_position);
		reprojected_position[0] = (reprojected_position[0] /
		                          (reprojected_position[3] * 2.0f) + 0.5f) * data->width;
		reprojected_position[1] = (reprojected_position[1] /
		                          (reprojected_position[3] * 2.0f) + 0.5f) * data->height * data->aspy;

		BKE_tracking_distort_v2(data->tracking, reprojected_position, reprojected_position);

		marker_position[0] = (marker->pos[0] + track->offset[0]) * data->width;
		marker_position[1] = (marker->pos[1] + track->offset[1]) * data->height * data->aspy;

		sub_v2_v2v2(delta, reprojected_position, marker_position);
		reprojection_error = len_v2(delta) * weight;

		immVertex2f(data->pos, scene_framenr, reprojection_error);
	}
}

static void tracking_error_segment_start_cb(void *userdata, MovieTrackingTrack *track, int coord, bool is_point)
{
	if (coord == 1) {
		TrackErrorCurveUserData *data = (TrackErrorCurveUserData *) userdata;
		float col[4] = {0.0f, 0.0f, 1.0f, 1.0f};

		if (track == data->active_track) {
			col[3] = 1.0f;
			GPU_line_width(2.0f);
		}
		else {
			col[3] = 0.5f;
			GPU_line_width(1.0f);
		}

		immUniformColor4fv(col);

		if (is_point) { /* This probably never happens here, but just in case... */
			immBeginAtMost(GPU_PRIM_POINTS, 1);
		}
		else {
			/* Graph can be composed of smaller segments, if any marker is disabled */
			immBeginAtMost(GPU_PRIM_LINE_STRIP, track->markersnr);
		}
	}
}

static void tracking_error_segment_end_cb(void *UNUSED(userdata), int coord)
{
	if (coord == 1) {
		immEnd();
	}
}

static void draw_tracks_error_curves(SpaceClip *sc, unsigned int pos)
{
	MovieClip *clip = ED_space_clip_get_clip(sc);
	MovieTracking *tracking = &clip->tracking;
	TrackErrorCurveUserData data;

	data.clip = clip;
	data.tracking = tracking;
	data.tracking_object = BKE_tracking_object_get_active(tracking);
	data.active_track = BKE_tracking_track_get_active(tracking);
	data.matrix_initialized = false;
	data.pos = pos;
	BKE_movieclip_get_size(clip, &sc->user, &data.width, &data.height);
	data.aspy = 1.0f / tracking->camera.pixel_aspect;

	if (!data.width || !data.height) {
		return;
	}

	clip_graph_tracking_values_iterate(sc,
	                                   (sc->flag & SC_SHOW_GRAPH_SEL_ONLY) != 0,
	                                   (sc->flag & SC_SHOW_GRAPH_HIDDEN) != 0,
	                                   &data,
	                                   tracking_error_segment_point_cb,
	                                   tracking_error_segment_start_cb,
	                                   tracking_error_segment_end_cb);
}

static void draw_frame_curves(SpaceClip *sc, unsigned int pos)
{
	MovieClip *clip = ED_space_clip_get_clip(sc);
	MovieTracking *tracking = &clip->tracking;
	MovieTrackingReconstruction *reconstruction = BKE_tracking_get_active_reconstruction(tracking);
	int i, lines = 0, prevfra = 0;

	immUniformColor3f(0.0f, 0.0f, 1.0f);

	for (i = 0; i < reconstruction->camnr; i++) {
		MovieReconstructedCamera *camera = &reconstruction->cameras[i];
		int framenr;

		if (lines && camera->framenr != prevfra + 1) {
			immEnd();
			lines = 0;
		}

		if (!lines) {
			immBeginAtMost(GPU_PRIM_LINE_STRIP, reconstruction->camnr);
			lines = 1;
		}

		framenr = BKE_movieclip_remap_clip_to_scene_frame(clip, camera->framenr);
		immVertex2f(pos, framenr, camera->error);

		prevfra = camera->framenr;
	}

	if (lines) {
		immEnd();
	}
}

void clip_draw_graph(SpaceClip *sc, ARegion *ar, Scene *scene)
{
	MovieClip *clip = ED_space_clip_get_clip(sc);
	View2D *v2d = &ar->v2d;
	View2DGrid *grid;
	short unitx = V2D_UNIT_FRAMESCALE, unity = V2D_UNIT_VALUES;

	/* grid */
	grid = UI_view2d_grid_calc(scene, v2d, unitx, V2D_GRID_NOCLAMP, unity, V2D_GRID_NOCLAMP, ar->winx, ar->winy);
	UI_view2d_grid_draw(v2d, grid, V2D_GRIDLINES_ALL);
	UI_view2d_grid_free(grid);

	if (clip) {
		uint pos = GPU_vertformat_attr_add(immVertexFormat(), "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
		immBindBuiltinProgram(GPU_SHADER_2D_UNIFORM_COLOR);

		GPU_point_size(3.0f);

		if (sc->flag & SC_SHOW_GRAPH_TRACKS_MOTION) {
			draw_tracks_motion_curves(v2d, sc, pos);
		}

		if (sc->flag & SC_SHOW_GRAPH_TRACKS_ERROR) {
			draw_tracks_error_curves(sc, pos);
		}

		if (sc->flag & SC_SHOW_GRAPH_FRAMES) {
			draw_frame_curves(sc, pos);
		}

		immUnbindProgram();
	}

	/* frame range */
	clip_draw_sfra_efra(v2d, scene);
}