/*
 * display.c
 *
 * Copyright © 2019 Thomas White <taw@bitwiz.me.uk>
 *
 * This file is part of NanoLight.
 *
 * NanoLight 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */


#include <gtk/gtk.h>
#include <getopt.h>
#include <string.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <glib.h>
#include <glib/gstdio.h>

#include <libintl.h>
#define _(x) gettext(x)

#include "nanolight.h"
#include "command.h"

#define OVERALL_BORDER (20.0)
#define OVERALL_SPLIT (0.5)
#define FIXTURE_BORDER (5.0)

int key_attrs[] = {
	0,
	INTENSITY,    /* F1 */
	PANTILT,      /* F2 */
	COLOUR,       /* F3 */
	GOBO,         /* F4 */
	PRISM,        /* F5 */
	FOCUS,        /* F6 */
	ZOOM,         /* F7 */
	IRIS,         /* F8 */
	FROST,        /* F9 */
	GOBO_ROTATE,  /* F10 */
	PRISM_ROTATE, /* F11 */
	GOBO_SPIN,    /* F12 */
};


static int fixture_selected(struct nanolight *nl, struct fixture *fix)
{
	int i;
	for ( i=0; i<nl->n_sel; i++ ) {
		if ( &nl->fixtures[nl->selection[i]] == fix ) return 1;
	}
	return 0;
}


static void draw_fixture(cairo_t *cr, PangoContext *pc, PangoFontDescription *fontdesc,
                         struct nanolight *nl, struct fixture *fix)
{
	PangoLayout *layout;
	const double w = 40.0;
	const double h = 3.0/2.0*w;
	char tmp[32];

	/* Pan/tilt (underneath rectangle) */
	if ( fix->cls->attributes & PANTILT ) {

		double x = w*(1.0 + fix->pan)/2.0;
		double y = h*(1.0 - fix->tilt)/2.0;

		cairo_move_to(cr, x, -1.0);
		cairo_line_to(cr, x, h+1.0);
		cairo_set_source_rgb(cr, 1.0, 0.0, 0.0);
		cairo_set_line_width(cr, 1.0);
		cairo_stroke(cr);

		cairo_move_to(cr, -1.0, y);
		cairo_line_to(cr, w+1.0, y);
		cairo_set_source_rgb(cr, 1.0, 0.0, 0.0);
		cairo_set_line_width(cr, 1.0);
		cairo_stroke(cr);

	}

	cairo_rectangle(cr, 0.0, 0.0, w, h);
	if ( fixture_selected(nl, fix) ) {
		cairo_set_source_rgba(cr, 0.3, 0.3, 0.9, 0.9);
	} else {
		cairo_set_source_rgba(cr, 0.3, 0.3, 0.3, 0.9);
	}
	cairo_fill_preserve(cr);
	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	cairo_set_line_width(cr, 1.0);
	cairo_stroke(cr);

	/* Label */
	layout = pango_layout_new(pc);
	pango_layout_set_text(layout, fix->label, -1);
	pango_layout_set_width(layout, (w*PANGO_SCALE)-4.0);
	pango_layout_set_alignment(layout, PANGO_ALIGN_CENTER);
	pango_layout_set_font_description(layout, fontdesc);
	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	cairo_move_to(cr, 0.0, 2.0);
	pango_cairo_show_layout(cr, layout);
	g_object_unref(layout);

	/* Intensity */
	snprintf(tmp, 32, "%.0f %%", fix->intensity*100.0);
	layout = pango_layout_new(pc);
	pango_layout_set_text(layout, tmp, -1);
	pango_layout_set_width(layout, (w*PANGO_SCALE)-4.0);
	pango_layout_set_alignment(layout, PANGO_ALIGN_CENTER);
	pango_layout_set_font_description(layout, fontdesc);
	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	cairo_move_to(cr, 0.0, 15.0);
	pango_cairo_show_layout(cr, layout);
	g_object_unref(layout);
}


static const char *attr_text(int cls)
{
	switch ( cls ) {
		case INTENSITY : return "Intensity";
		case PANTILT : return "Pan/tilt";
		case COLOUR : return "Colour";
		case GOBO : return "Gobo";
		case PRISM : return "Prism";
		case FOCUS : return "Focus";
		case ZOOM : return "Zoom";
		case IRIS : return "Iris";
		case FROST : return "Frost";
		case GOBO_ROTATE : return "Gobo rotate";
		case PRISM_ROTATE : return "Prism rotate";
		case GOBO_SPIN : return "Gobo spin";
		case PRISM_SPIN : return "Prism spin";
	}
	return "(unknown)";
}


static gboolean draw_sig(GtkWidget *widget, cairo_t *cr, struct nanolight *nl)
{
	int w, h;
	int ch;
	int i;
	PangoContext *pc;
	PangoFontDescription *fontdesc;
	double x, y;
	PangoRectangle cursor;

	w = gtk_widget_get_allocated_width(widget);
	h = gtk_widget_get_allocated_height(widget);
	pc = gtk_widget_get_pango_context(widget);

	/* Overall background */
	cairo_set_source_rgb(cr, 0.0, 0.0, 0.2);
	cairo_paint(cr);

	/* Separator between fixture and cue areas */
	cairo_move_to(cr, w*OVERALL_SPLIT, OVERALL_BORDER);
	cairo_line_to(cr, w*OVERALL_SPLIT, h - OVERALL_BORDER);
	cairo_set_line_width(cr, 3.0);
	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	cairo_set_line_cap(cr, CAIRO_LINE_CAP_ROUND);
	cairo_stroke(cr);

	/* Fixtures */
	cairo_save(cr);
	cairo_translate(cr, OVERALL_BORDER, OVERALL_BORDER);
	x = FIXTURE_BORDER;
	y = FIXTURE_BORDER;
	fontdesc = pango_font_description_from_string("Comfortaa Bold 8");
	for ( i=0; i<nl->n_fixtures; i++ ) {
		cairo_save(cr);
		cairo_translate(cr, x, y);
		cairo_scale(cr, nl->fixture_width/40.0, nl->fixture_width/40.0);
		draw_fixture(cr, pc, fontdesc, nl, &nl->fixtures[i]);
		cairo_restore(cr);
		x += nl->fixture_width + FIXTURE_BORDER*2;
		if ( x + nl->fixture_width + FIXTURE_BORDER*2 > w*OVERALL_SPLIT ) {
			x = FIXTURE_BORDER;
			y += nl->fixture_width*3.0/2.0 + FIXTURE_BORDER*2;
		}
	}
	cairo_restore(cr);

	/* Command line */
	pango_layout_set_text(nl->layout, nl->cmdline, -1);
	cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	cairo_save(cr);
	cairo_translate(cr, OVERALL_BORDER, h - OVERALL_BORDER - 20.0);
	cairo_move_to(cr, 0.0, 0.0);
	pango_cairo_show_layout(cr, nl->layout);
	pango_layout_get_cursor_pos(nl->layout, nl->cursor_idx, &cursor, NULL);
	x = pango_units_to_double(cursor.x);
	y = pango_units_to_double(cursor.y);
	ch = pango_units_to_double(cursor.height);
	cairo_move_to(cr, x, y);
	cairo_line_to(cr, x, y+ch);
	cairo_set_line_width(cr, 3.0);
	cairo_set_line_cap(cr, CAIRO_LINE_CAP_ROUND);
	cairo_set_source_rgb(cr, 0.8, 0.4, 0.4);
	cairo_stroke(cr);
	cairo_restore(cr);

	/* Selected attribute indicator */
	if ( nl->n_sel > 0 ) {
		pango_layout_set_text(nl->sa_layout, attr_text(nl->sel_attr), -1);
		cairo_set_source_rgb(cr, 1.0, 0.0, 0.0);
		pango_layout_set_width(nl->sa_layout, pango_units_from_double(200.0));
		cairo_move_to(cr, w - 200.0 - OVERALL_BORDER, h-OVERALL_BORDER-20.0);
		pango_cairo_show_layout(cr, nl->sa_layout);
	}

	return FALSE;
}


static void redraw(struct nanolight *nl)
{
	gint w, h;
	w = gtk_widget_get_allocated_width(GTK_WIDGET(nl->da));
	h = gtk_widget_get_allocated_height(GTK_WIDGET(nl->da));
	gtk_widget_queue_draw_area(GTK_WIDGET(nl->da), 0, 0, w, h);
}


static gboolean im_commit_sig(GtkIMContext *im, gchar *str, struct nanolight *nl)
{
	size_t cmd_len = strlen(nl->cmdline);
	if ( cmd_len+strlen(str) > 1023 ) return FALSE;
	strcat(nl->cmdline, str);
	nl->cursor_idx += strlen(str);
	redraw(nl);
	return FALSE;
}


static size_t delete_char(char *str)
{
	char *last;
	size_t len;
	if ( str[0] == '\0' ) return 0;
	last = g_utf8_find_prev_char(str, str+strlen(str));
	len = strlen(last);
	last[0] = '\0';
	return len;
}


static void set_start_pantilt(struct nanolight *nl)
{
	int i;
	for ( i=0; i<nl->n_sel; i++ ) {
		struct fixture *fix = &nl->fixtures[nl->selection[i]];
		fix->pan_start = fix->pan;
		fix->tilt_start = fix->tilt;
	}
}


static gboolean button_press_sig(GtkWidget *da, GdkEventButton *event, struct nanolight *nl)
{
#if 0
	GdkSeat *seat;
	GdkWindow *win = gtk_widget_get_window(nl->da);

	seat = gdk_display_get_default_seat(gdk_display_get_default());
	nl->pointer = gdk_seat_get_pointer(seat);
#endif

	set_start_pantilt(nl);
	nl->x_orig = event->x;
	nl->y_orig = event->y;
	nl->dragging = 1;

	return FALSE;
}


static gboolean button_release_sig(GtkWidget *da, GdkEventButton *event, struct nanolight *nl)
{
	nl->dragging = 0;
	return FALSE;
}


static gboolean motion_sig(GtkWidget *da, GdkEventMotion *event, struct nanolight *nl)
{
	int i;
	double x_inc, y_inc;
	int shift;
	double speed;

	if ( !nl->dragging ) return FALSE;
	if ( nl->sel_attr != PANTILT ) return FALSE;

	x_inc = event->x - nl->x_orig;
	y_inc = nl->y_orig - event->y;  /* Mouse up means increase */

	shift = event->state & GDK_SHIFT_MASK;
	if ( shift != nl->fine ) {
		nl->fine = shift;
		set_start_pantilt(nl);
		nl->x_orig = event->x;
		nl->y_orig = event->y;
		return FALSE;
	}

	speed = shift ? (1.0/(256.0*500.0)) : (1.0/500.0);

	for ( i=0; i<nl->n_sel; i++ ) {

		struct fixture *fix = &nl->fixtures[nl->selection[i]];
		if ( !(fix->cls->attributes & PANTILT) ) continue;

		fix->pan = fix->pan_start + x_inc*speed;
		fix->tilt = fix->tilt_start + y_inc*speed;
		if ( fix->pan > 1.0 ) fix->pan = 1.0;
		if ( fix->pan < -1.0 ) fix->pan = -1.0;
		if ( fix->tilt > 1.0 ) fix->tilt = 1.0;
		if ( fix->tilt < -1.0 ) fix->tilt = -1.0;

	}

	redraw(nl);
	return FALSE;
}


static void home_value(struct nanolight *nl)
{
	int i;
	for ( i=0; i<nl->n_sel; i++ ) {

#if 0
		struct fixture *fix = &nl->fixtures[nl->selection[i]];
		int n;

		if ( nl->sel_attr == ATT_TILT ) {
			if ( find_attribute(fix, ATT_PAN, &n) ) {
				fix->attr_vals[n] = fix->cls->attrs[n].home;
			}
			if ( find_attribute(fix, ATT_TILT, &n) ) {
				fix->attr_vals[n] = fix->cls->attrs[n].home;
			}
			nl->dragging = 0;
		} else {
			if ( find_attribute(fix, nl->sel_attr, &n) ) {
				fix->attr_vals[n] = fix->cls->attrs[n].home;
			}
		}
#endif


	}
	redraw(nl);
}


static void execute_command(struct nanolight *nl)
{
	if ( command_run(nl->cmdline, nl) == 0 ) {
		nl->cmdline[0] = '\0';
		nl->cursor_idx = 0;
	}
	redraw(nl);
}


static gboolean key_release_sig(GtkWidget *da, GdkEventKey *event, struct nanolight *nl)
{
	switch ( event->keyval ) {

		case GDK_KEY_KP_Enter :
		nl->go_lock = 0;
		break;

		case GDK_KEY_KP_Add :
		nl->sb_lock = 0;
		break;
	}

	return FALSE;
}


static gboolean key_press_sig(GtkWidget *da, GdkEventKey *event, struct nanolight *nl)
{
	gboolean r;
	int claim = 1;

	switch ( event->keyval ) {

		case GDK_KEY_Left :
		break;

		case GDK_KEY_Right :
		break;

		case GDK_KEY_Up :
		//change_stop_attr(nl, +1);
		break;

		case GDK_KEY_Down :
		//change_stop_attr(nl, -1);
		break;

		case GDK_KEY_Return :
		execute_command(nl);
		break;

		case GDK_KEY_Escape :
		nl->cmdline[0] = '\0';
		nl->cursor_idx = 0;
		nl->n_sel = 0;
		nl->dragging = 0;
		break;

		case GDK_KEY_BackSpace :
		nl->cursor_idx -= delete_char(nl->cmdline);
		break;

		case GDK_KEY_KP_Enter :
		if ( !nl->go_lock ) {
			printf("Go!\n");
			nl->go_lock = 1;
		}
		break;

		case GDK_KEY_KP_Add :
		if ( !nl->sb_lock ) {
			printf("Stop/back!\n");
			nl->sb_lock = 1;
		}
		break;

		case GDK_KEY_Home :
		home_value(nl);
		break;

		case GDK_KEY_F1 :
		nl->sel_attr = key_attrs[1];
		nl->dragging = 0;
		break;

		case GDK_KEY_F2 :
		nl->sel_attr = key_attrs[2];
		nl->dragging = 0;
		break;

		case GDK_KEY_F3 :
		nl->sel_attr = key_attrs[3];
		nl->dragging = 0;
		break;

		case GDK_KEY_F4 :
		nl->sel_attr = key_attrs[4];
		nl->dragging = 0;
		break;

		case GDK_KEY_F5 :
		nl->sel_attr = key_attrs[5];
		nl->dragging = 0;
		break;

		case GDK_KEY_F6 :
		nl->sel_attr = key_attrs[6];
		nl->dragging = 0;
		break;

		case GDK_KEY_F7 :
		nl->sel_attr = key_attrs[7];
		nl->dragging = 0;
		break;

		case GDK_KEY_F8 :
		nl->sel_attr = key_attrs[8];
		nl->dragging = 0;
		break;

		case GDK_KEY_F9 :
		nl->sel_attr = key_attrs[9];
		nl->dragging = 0;
		break;

		case GDK_KEY_F10 :
		nl->sel_attr = key_attrs[10];
		nl->dragging = 0;
		break;

		case GDK_KEY_F11 :
		nl->sel_attr = key_attrs[11];
		nl->dragging = 0;
		break;

		case GDK_KEY_F12 :
		nl->sel_attr = key_attrs[12];
		nl->dragging = 0;
		break;

		default :
		claim = 0;
		break;

	}

	if ( !claim ) {
		/* Throw the event to the IM context and let it sort things out */
		r = gtk_im_context_filter_keypress(GTK_IM_CONTEXT(nl->im_context), event);
		if ( r ) claim = 1;
	} else {
		redraw(nl);
	}

	if ( claim ) return TRUE;
	return FALSE;
}


static gint realise_sig(GtkWidget *da, struct nanolight *nl)
{
	GdkWindow *win = gtk_widget_get_window(da);
	PangoContext *pc;
	PangoFontDescription *fontdesc;

	/* Keyboard and input method stuff */
	nl->im_context = gtk_im_multicontext_new();
	gtk_im_context_set_client_window(GTK_IM_CONTEXT(nl->im_context), win);
	gdk_window_set_accept_focus(win, TRUE);
	g_signal_connect(G_OBJECT(nl->im_context), "commit", G_CALLBACK(im_commit_sig), nl);
	g_signal_connect(G_OBJECT(da), "key-press-event", G_CALLBACK(key_press_sig), nl);
	g_signal_connect(G_OBJECT(da), "key-release-event", G_CALLBACK(key_release_sig), nl);
	g_signal_connect(G_OBJECT(da), "button-press-event", G_CALLBACK(button_press_sig), nl);
	g_signal_connect(G_OBJECT(da), "button-release-event", G_CALLBACK(button_release_sig), nl);
	g_signal_connect(G_OBJECT(da), "motion-notify-event", G_CALLBACK(motion_sig), nl);

	pc = gtk_widget_get_pango_context(da);
	fontdesc = pango_font_description_from_string("Comfortaa Bold 16");

	nl->layout = pango_layout_new(pc);
	pango_layout_set_alignment(nl->layout, PANGO_ALIGN_LEFT);
	pango_layout_set_font_description(nl->layout, fontdesc);

	nl->sa_layout = pango_layout_new(pc);
	pango_layout_set_alignment(nl->sa_layout, PANGO_ALIGN_RIGHT);
	pango_layout_set_font_description(nl->sa_layout, fontdesc);

	return FALSE;
}


void create_main_window(struct nanolight *nl)
{
	GtkWidget *mainwindow;
	GtkWidget *da;

	/* Create main window */
	mainwindow = gtk_window_new(GTK_WINDOW_TOPLEVEL);
	gtk_window_fullscreen(GTK_WINDOW(mainwindow));
	g_signal_connect_swapped(G_OBJECT(mainwindow), "destroy", gtk_main_quit, NULL);

	da = gtk_drawing_area_new();
	nl->da = da;
	gtk_container_add(GTK_CONTAINER(mainwindow), GTK_WIDGET(da));
	gtk_widget_set_can_focus(GTK_WIDGET(da), TRUE);
	gtk_widget_add_events(da, GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK
	                        | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK
	                        | GDK_BUTTON_MOTION_MASK);
	g_signal_connect(G_OBJECT(da), "draw", G_CALLBACK(draw_sig), nl);
	g_signal_connect(G_OBJECT(da), "realize", G_CALLBACK(realise_sig), nl);

	gtk_widget_grab_focus(GTK_WIDGET(da));
	gtk_widget_show_all(mainwindow);
}