#include <2geom/coord.h>

#include <2geom/transforms.h>

#include "sp-canvas-util.h"

#include "sp-ctrlpoint.h"

#include "guideline.h"

#include "display/cairo-utils.h"

#include "inkscape.h" // for inkscape_active_desktop()

#include "desktop.h"

#include "sp-namedview.h"

#include "display/sp-canvas.h"

#include "ui/control-manager.h"

using Inkscape::ControlManager;

static void sp_guideline_destroy(SPCanvasItem *object);

static void sp_guideline_update(SPCanvasItem *item, Geom::Affine const &affine, unsigned int flags);

static void sp_guideline_render(SPCanvasItem *item, SPCanvasBuf *buf);

static double sp_guideline_point(SPCanvasItem *item, Geom::Point p, SPCanvasItem **actual_item);

static void sp_guideline_drawline (SPCanvasBuf *buf, gint x0, gint y0, gint x1, gint y1, guint32 rgba);

G_DEFINE_TYPE(SPGuideLine, sp_guideline, SP_TYPE_CANVAS_ITEM);

static void sp_guideline_class_init(SPGuideLineClass *c)

{

SPCanvasItemClass *item_class = SP_CANVAS_ITEM_CLASS(c);

item_class->destroy = sp_guideline_destroy;

item_class->update = sp_guideline_update;

item_class->render = sp_guideline_render;

item_class->point = sp_guideline_point;

}

static void sp_guideline_init(SPGuideLine *gl)

{

gl->rgba = 0x0000ff7f;

gl->locked = false;

gl->normal_to_line = Geom::Point(0,1);

gl->angle = 3.14159265358979323846/2;

gl->point_on_line = Geom::Point(0,0);

gl->sensitive = 0;

gl->origin = NULL;

gl->label = NULL;

}

static void sp_guideline_destroy(SPCanvasItem *object)

{

g_return_if_fail (object != NULL);

g_return_if_fail (SP_IS_GUIDELINE (object));

//g_return_if_fail (SP_GUIDELINE(object)->origin != NULL);

//g_return_if_fail (SP_IS_CTRLPOINT(SP_GUIDELINE(object)->origin));

SPGuideLine *gl = SP_GUIDELINE(object);

if (gl->origin != NULL && SP_IS_CTRLPOINT(gl->origin)) {

sp_canvas_item_destroy(gl->origin);

} else {

// FIXME: This branch shouldn't be reached (although it seems to be harmless).

//g_error("Why can it be that gl->origin is not a valid SPCtrlPoint?\n");

}

if (gl->label) {

g_free(gl->label);

}

SP_CANVAS_ITEM_CLASS(sp_guideline_parent_class)->destroy(object);

}

static void sp_guideline_render(SPCanvasItem *item, SPCanvasBuf *buf)

{

//TODO: the routine that renders the label of a specific guideline sometimes

// ends up erasing the labels of the other guidelines.

// Maybe we should render all labels everytime.

SPGuideLine const *gl = SP_GUIDELINE (item);

cairo_save(buf->ct);

cairo_translate(buf->ct, -buf->rect.left(), -buf->rect.top());

ink_cairo_set_source_rgba32(buf->ct, gl->rgba);

cairo_set_line_width(buf->ct, 1);

cairo_set_line_cap(buf->ct, CAIRO_LINE_CAP_SQUARE);

cairo_set_font_size(buf->ct, 10);

Geom::Point normal_dt = /*unit_vector*/(gl->normal_to_line * gl->affine.withoutTranslation()); // note that normal_dt does not have unit length

Geom::Point point_on_line_dt = gl->point_on_line * gl->affine;

if (gl->label) {

int px = round(point_on_line_dt[Geom::X]);

int py = round(point_on_line_dt[Geom::Y]);

cairo_save(buf->ct);

cairo_translate(buf->ct, px, py);

cairo_rotate(buf->ct, atan2(normal_dt.cw()));

cairo_translate(buf->ct, 0, -5);

cairo_move_to(buf->ct, 0, 0);

cairo_show_text(buf->ct, gl->label);

cairo_restore(buf->ct);

}

if ( Geom::are_near(normal_dt[Geom::Y], 0.) ) { // is vertical?

int position = round(point_on_line_dt[Geom::X]);

cairo_move_to(buf->ct, position + 0.5, buf->rect.top() + 0.5);

cairo_line_to(buf->ct, position + 0.5, buf->rect.bottom() - 0.5);

cairo_stroke(buf->ct);

} else if ( Geom::are_near(normal_dt[Geom::X], 0.) ) { // is horizontal?

int position = round(point_on_line_dt[Geom::Y]);

cairo_move_to(buf->ct, buf->rect.left() + 0.5, position + 0.5);

cairo_line_to(buf->ct, buf->rect.right() - 0.5, position + 0.5);

cairo_stroke(buf->ct);

} else {

// render angled line. Once intersection has been detected, draw from there.

Geom::Point parallel_to_line( normal_dt.ccw() );

//try to intersect with left vertical of rect

double y_intersect_left = (buf->rect.left() - point_on_line_dt[Geom::X]) * parallel_to_line[Geom::Y] / parallel_to_line[Geom::X] + point_on_line_dt[Geom::Y];

if ( (y_intersect_left >= buf->rect.top()) && (y_intersect_left <= buf->rect.bottom()) ) {

// intersects with left vertical!

double y_intersect_right = (buf->rect.right() - point_on_line_dt[Geom::X]) * parallel_to_line[Geom::Y] / parallel_to_line[Geom::X] + point_on_line_dt[Geom::Y];

sp_guideline_drawline (buf, buf->rect.left(), static_cast<gint>(round(y_intersect_left)), buf->rect.right(), static_cast<gint>(round(y_intersect_right)), gl->rgba);

goto end;

}

//try to intersect with right vertical of rect

double y_intersect_right = (buf->rect.right() - point_on_line_dt[Geom::X]) * parallel_to_line[Geom::Y] / parallel_to_line[Geom::X] + point_on_line_dt[Geom::Y];

if ( (y_intersect_right >= buf->rect.top()) && (y_intersect_right <= buf->rect.bottom()) ) {

// intersects with right vertical!

sp_guideline_drawline (buf, buf->rect.right(), static_cast<gint>(round(y_intersect_right)), buf->rect.left(), static_cast<gint>(round(y_intersect_left)), gl->rgba);

goto end;

}

//try to intersect with top horizontal of rect

double x_intersect_top = (buf->rect.top() - point_on_line_dt[Geom::Y]) * parallel_to_line[Geom::X] / parallel_to_line[Geom::Y] + point_on_line_dt[Geom::X];

if ( (x_intersect_top >= buf->rect.left()) && (x_intersect_top <= buf->rect.right()) ) {

// intersects with top horizontal!

double x_intersect_bottom = (buf->rect.bottom() - point_on_line_dt[Geom::Y]) * parallel_to_line[Geom::X] / parallel_to_line[Geom::Y] + point_on_line_dt[Geom::X];

sp_guideline_drawline (buf, static_cast<gint>(round(x_intersect_top)), buf->rect.top(), static_cast<gint>(round(x_intersect_bottom)), buf->rect.bottom(), gl->rgba);

goto end;

}

//try to intersect with bottom horizontal of rect

double x_intersect_bottom = (buf->rect.bottom() - point_on_line_dt[Geom::Y]) * parallel_to_line[Geom::X] / parallel_to_line[Geom::Y] + point_on_line_dt[Geom::X];

if ( (x_intersect_top >= buf->rect.left()) && (x_intersect_top <= buf->rect.right()) ) {

// intersects with bottom horizontal!

sp_guideline_drawline (buf, static_cast<gint>(round(x_intersect_bottom)), buf->rect.bottom(), static_cast<gint>(round(x_intersect_top)), buf->rect.top(), gl->rgba);

goto end;

}

}

end:

cairo_restore(buf->ct);

}

static void sp_guideline_update(SPCanvasItem *item, Geom::Affine const &affine, unsigned int flags)

{

SPGuideLine *gl = SP_GUIDELINE(item);

if ((SP_CANVAS_ITEM_CLASS(sp_guideline_parent_class))->update) {

(SP_CANVAS_ITEM_CLASS(sp_guideline_parent_class))->update(item, affine, flags);

}

gl->affine = affine;

sp_ctrlpoint_set_coords(gl->origin, gl->point_on_line);

sp_canvas_item_request_update(SP_CANVAS_ITEM (gl->origin));

Geom::Point pol_transformed = gl->point_on_line*affine;

if (gl->is_horizontal()) {

sp_canvas_update_bbox (item, -1000000, round(pol_transformed[Geom::Y] - 16), 1000000, round(pol_transformed[Geom::Y] + 1));

} else if (gl->is_vertical()) {

sp_canvas_update_bbox (item, round(pol_transformed[Geom::X]), -1000000, round(pol_transformed[Geom::X] + 16), 1000000);

} else {

//TODO: labels in angled guidelines are not showing up for some reason.

sp_canvas_update_bbox (item, -1000000, -1000000, 1000000, 1000000);

}

}

static double sp_guideline_point(SPCanvasItem *item, Geom::Point p, SPCanvasItem **actual_item)

{

SPGuideLine *gl = SP_GUIDELINE (item);

if (!gl->sensitive) {

return Geom::infinity();

}

*actual_item = item;

Geom::Point vec = gl->normal_to_line * gl->affine.withoutTranslation();

double distance = Geom::dot((p - gl->point_on_line * gl->affine), unit_vector(vec));

return MAX(fabs(distance)-1, 0);

}

SPCanvasItem *sp_guideline_new(SPCanvasGroup *parent, char* label, Geom::Point point_on_line, Geom::Point normal)

{

SPCanvasItem *item = sp_canvas_item_new(parent, SP_TYPE_GUIDELINE, NULL);

SPCanvasItem *origin = ControlManager::getManager().createControl(parent, Inkscape::CTRL_TYPE_ORIGIN);

ControlManager::getManager().track(origin);

SPGuideLine *gl = SP_GUIDELINE(item);

SPCtrlPoint *cp = SP_CTRLPOINT(origin);

gl->origin = cp;

normal.normalize();

gl->label = label;

gl->locked = false;

gl->normal_to_line = normal;

gl->angle = tan( -gl->normal_to_line[Geom::X] / gl->normal_to_line[Geom::Y]);

sp_guideline_set_position(gl, point_on_line);

sp_ctrlpoint_set_coords(cp, point_on_line);

return item;

}

void sp_guideline_set_label(SPGuideLine *gl, const char* label)

{

if (gl->label) {

g_free(gl->label);

}

gl->label = g_strdup(label);

sp_canvas_item_request_update(SP_CANVAS_ITEM (gl));

}

void sp_guideline_set_locked(SPGuideLine *gl, const bool locked)

{

gl->locked = locked;

sp_canvas_item_request_update(SP_CANVAS_ITEM (gl));

}

void sp_guideline_set_position(SPGuideLine *gl, Geom::Point point_on_line)

{

gl->point_on_line = point_on_line;

sp_canvas_item_request_update(SP_CANVAS_ITEM (gl));

}

void sp_guideline_set_normal(SPGuideLine *gl, Geom::Point normal_to_line)

{

gl->normal_to_line = normal_to_line;

gl->angle = tan( -normal_to_line[Geom::X] / normal_to_line[Geom::Y]);

sp_canvas_item_request_update(SP_CANVAS_ITEM (gl));

}

void sp_guideline_set_color(SPGuideLine *gl, unsigned int rgba)

{

gl->rgba = rgba;

sp_ctrlpoint_set_color(gl->origin, rgba);

sp_canvas_item_request_update(SP_CANVAS_ITEM(gl));

}

void sp_guideline_set_sensitive(SPGuideLine *gl, int sensitive)

{

gl->sensitive = sensitive;

}

void sp_guideline_delete(SPGuideLine *gl)

{

//gtk_object_destroy(GTK_OBJECT(gl->origin));

sp_canvas_item_destroy(SP_CANVAS_ITEM(gl));

}

static void

sp_guideline_drawline (SPCanvasBuf *buf, gint x0, gint y0, gint x1, gint y1, guint32 /*rgba*/)

{

cairo_move_to(buf->ct, x0 + 0.5, y0 + 0.5);

cairo_line_to(buf->ct, x1 + 0.5, y1 + 0.5);

cairo_stroke(buf->ct);

}