/*
 * Tab
 *
 * Copyright (C) 2017  Patrick McDermott
 *
 * This file is part of Marquee.
 *
 * Marquee 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.
 *
 * Marquee 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 Marquee.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>

#include <gtk/gtk.h>

#include "tab.h"
#include "tab-chrome.h"
#include "tab-body.h"

static void
update_tab_image(MqTab *tab)
{
	gtk_image_set_from_surface(GTK_IMAGE(tab->tab_image), tab->favicon);
}

static void
update_tab_label(MqTab *tab)
{
	gchar *label;

	label = g_strdup_printf("%d. %s", tab->position, tab->title);
	gtk_label_set_text(GTK_LABEL(tab->tab_label), label);
	gtk_widget_set_tooltip_text(tab->tab, label);
	g_free(label);
}

static void
update_positions(MqTab *node, gint step)
{
	if (node) {
		node->position += step;
		update_tab_label(node);
		if (node->next) {
			update_positions(node->next, step);
		} else if (node->parent && node->parent->next) {
			update_positions(node->parent->next, step);
		}
	}
}

static void
update_tree_sizes(MqTab *node, guint step)
{
	if (node) {
		node->tree_size += step;
		update_tree_sizes(node->parent, step);
	}
}

static void
append_child(MqTab *new_node, MqTab *parent)
{
	new_node->parent = parent;
	new_node->next = NULL;
	new_node->prev = parent->last_child;  /* May be NULL */
	new_node->first_child = new_node->last_child = NULL;
	new_node->tree_size = 0;  /* Will be updated */
	if (parent->last_child) {
		new_node->position = parent->last_child->position;
		parent->last_child->next = new_node;
	} else {
		new_node->position = parent->position;
		parent->first_child = new_node;
	}
	parent->last_child = new_node;
	update_positions(new_node, 1);
	update_tree_sizes(new_node, 1);
}

static void
append_sibling(MqTab *new_node, MqTab *prev_sibling)
{
	new_node->parent = prev_sibling->parent;
	new_node->prev = prev_sibling;
	new_node->next = prev_sibling->next;  /* May be NULL */
	new_node->first_child = new_node->last_child = NULL;
	new_node->position = prev_sibling->position;  /* Will be updated */
	new_node->tree_size = 0;  /* Will be updated */
	if (prev_sibling->next) {
		prev_sibling->next->prev = new_node;
	}
	prev_sibling->next = new_node;
	update_positions(new_node, 1);
	update_tree_sizes(new_node, 1);
}

static void
reload_tab_clicked_cb(GtkWidget __attribute__((unused)) *button, MqTab *tab)
{
	webkit_web_view_reload(tab->web_view);
	gtk_widget_hide(tab->popover);
}

static void
new_tab_clicked_cb(GtkWidget __attribute__((unused)) *button, MqTab *tab)
{
	mq_tab_new(tab->window, NULL, tab);
	gtk_widget_hide(tab->popover);
}

static void
new_window_clicked_cb(GtkWidget __attribute__((unused)) *button, MqTab *tab)
{
	mq_application_add_window(tab->application, NULL);
	gtk_widget_hide(tab->popover);
}

static void
tab_list_button_toggled_cb(GtkToggleButton *toggle_button, GtkWidget *tab_list)
{
	if (gtk_toggle_button_get_active(toggle_button)) {
		gtk_widget_show(tab_list);
	} else {
		gtk_widget_hide(tab_list);
	}
}

#define BUTTON_ROWS 2
#define BUTTON_COLS 4
#define NEW_BUTTON(Y, X, ICON, TOOLTIP) \
	do { \
		buttons[Y * BUTTON_COLS + X] = gtk_button_new_from_icon_name(\
			ICON, GTK_ICON_SIZE_BUTTON); \
		gtk_widget_set_tooltip_text(buttons[Y * BUTTON_COLS + X], \
			TOOLTIP); \
		gtk_widget_set_can_focus(buttons[Y * BUTTON_COLS + X], FALSE); \
		gtk_grid_attach(GTK_GRID(button_grid), \
			buttons[Y * BUTTON_COLS + X], X, Y, 1, 1); \
	} while (0)
#define NEW_TOGGLE(Y, X, ICON, TOOLTIP) \
	do { \
		buttons[Y * BUTTON_COLS + X] = gtk_toggle_button_new(); \
		gtk_button_set_image(GTK_BUTTON(buttons[Y * BUTTON_COLS + X]), \
			gtk_image_new_from_icon_name(ICON, \
				GTK_ICON_SIZE_BUTTON)); \
		gtk_widget_set_tooltip_text(buttons[Y * BUTTON_COLS + X], \
			TOOLTIP); \
		gtk_widget_set_can_focus(buttons[Y * BUTTON_COLS + X], FALSE); \
		gtk_grid_attach(GTK_GRID(button_grid), \
			buttons[Y * BUTTON_COLS + X], X, Y, 1, 1); \
	} while (0)
#define CLICKED_CB(Y, X, CB) \
	g_signal_connect(buttons[Y * BUTTON_COLS + X], "clicked", CB, tab)

static gboolean
tab_label_button_press_cb(GtkWidget *widget, GdkEvent *event, MqTab *tab)
{
	GtkWidget *button_grid;
	GtkWidget *buttons[BUTTON_ROWS * BUTTON_COLS];
	GtkWidget *tab_list;
	GtkWidget *tab_list_scrolled_window;
	GtkWidget *box;

	/* Make sure this is a right mouse button press event. */
	if (event->type != GDK_BUTTON_PRESS || event->button.button != 3) {
		return FALSE;
	}

	/* Set up button grid. */
	button_grid = gtk_grid_new();
	gtk_widget_set_halign(button_grid, GTK_ALIGN_CENTER);

	/* Set up buttons. */
	NEW_BUTTON(0, 0, "view-refresh",       "Reload tab");
	NEW_BUTTON(0, 1, "edit-copy",          "Duplicate tab");
	NEW_BUTTON(0, 2, "window-new",         "Move tab to new window");
	NEW_BUTTON(0, 3, "window-close",       "Close tab");
	NEW_BUTTON(1, 0, "tab-new-symbolic",   "New tab");
	NEW_BUTTON(1, 1, "window-new",         "New window");
	NEW_BUTTON(1, 2, "edit-undo",          "Undo close tab");
	NEW_TOGGLE(1, 3, "view-list-symbolic", "Tab list...");

	CLICKED_CB(0, 0, G_CALLBACK(reload_tab_clicked_cb));
	CLICKED_CB(1, 0, G_CALLBACK(new_tab_clicked_cb));
	CLICKED_CB(1, 1, G_CALLBACK(new_window_clicked_cb));

	/* Set up the tab list. */
	tab_list = gtk_label_new("Tab list");

	/* Set up the tab list scrolled window.
	 *
	 * The following GtkScrolledWindow widget has a hardcoded minimum size,
	 * because there seems to be (in GTK+ versions before 3.22) no way to
	 * set the natural size of GtkScrolledWindow and its GtkViewport.
	 *
	 * See tab-chrome.c for more information. */
	tab_list_scrolled_window = gtk_scrolled_window_new(NULL, NULL);
	gtk_scrolled_window_set_min_content_width(
		GTK_SCROLLED_WINDOW(tab_list_scrolled_window), 400);
	gtk_scrolled_window_set_min_content_height(
		GTK_SCROLLED_WINDOW(tab_list_scrolled_window), 200);
	gtk_container_add(GTK_CONTAINER(tab_list_scrolled_window), tab_list);

	/* Add tab list toggle button handler. */
	g_signal_connect(buttons[1 * BUTTON_COLS + 3], "toggled",
		G_CALLBACK(tab_list_button_toggled_cb),
		tab_list_scrolled_window);

	/* Set up the button rows box. */
	box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 0);
	gtk_box_pack_start(GTK_BOX(box), button_grid,
		TRUE, FALSE, 0);
	gtk_box_pack_start(GTK_BOX(box), tab_list_scrolled_window,
		TRUE, FALSE, 0);

	/* Set up the popover. */
	tab->popover = gtk_popover_new(widget);
	gtk_container_add(GTK_CONTAINER(tab->popover), box);

	/* NB: gtk_popover_popup() is new in GTK+ 3.22. */
	gtk_widget_show_all(tab->popover);
	gtk_widget_hide(tab_list_scrolled_window);

	return FALSE;
}

#undef BUTTON_ROWS
#undef BUTTON_COLS
#undef NEW_BUTTON
#undef NEW_TOGGLE
#undef CLICKED_CB

static void
mq_tab_populate_tab(MqTab *tab)
{
	GtkWidget *close_button;
	GtkWidget *box;

	tab->title = "New tab";

	/* Set up tab image. */
	tab->tab_image = gtk_image_new_from_icon_name("text-x-generic",
		GTK_ICON_SIZE_BUTTON);

	/* Set up tab label. */
	tab->tab_label = gtk_label_new(NULL);
	gtk_label_set_ellipsize(GTK_LABEL(tab->tab_label),
		PANGO_ELLIPSIZE_END);
	gtk_widget_set_hexpand(tab->tab_label, TRUE);
	gtk_widget_set_size_request(tab->tab_label, 50, 1);

	/* Set up close button. */
	close_button = gtk_button_new_from_icon_name("window-close",
		GTK_ICON_SIZE_BUTTON);
	gtk_widget_set_tooltip_text(close_button, "Close tab");

	/* Pack tab box. */
	box = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 0);
	gtk_box_pack_start(GTK_BOX(box), tab->tab_image, FALSE, FALSE, 0);
	gtk_box_pack_start(GTK_BOX(box), tab->tab_label, TRUE, TRUE, 0);
	gtk_box_pack_start(GTK_BOX(box), close_button, FALSE, FALSE, 0);
	gtk_widget_show_all(box);

	/* Set up event box. */
	tab->tab = gtk_event_box_new();
	g_signal_connect(tab->tab, "button-press-event",
		G_CALLBACK(tab_label_button_press_cb), tab);
	gtk_event_box_set_visible_window(GTK_EVENT_BOX(tab->tab),
		FALSE);
	gtk_container_add(GTK_CONTAINER(tab->tab), box);
}

static void
favicon_cb(WebKitWebView __attribute__((unused)) *web_view,
	GParamSpec __attribute__((unused)) *paramspec, MqTab *tab)
{
	tab->favicon = webkit_web_view_get_favicon(tab->web_view);
	update_tab_image(tab);
}

static void
title_cb(WebKitWebView __attribute__((unused)) *web_view,
	GParamSpec __attribute__((unused)) *paramspec, MqTab *tab)
{
	tab->title = webkit_web_view_get_title(tab->web_view);
	update_tab_label(tab);
}

static MqTab *
init_non_root(MqWindow *window, gchar *uri)
{
	MqTab *tab;

	tab = malloc(sizeof(*tab));
	tab->parent = NULL;
	tab->prev = NULL;
	tab->next = NULL;
	tab->first_child = tab->last_child = NULL;
	tab->tree_size = 1;
	tab->window = window;
	tab->application = mq_window_get_application(window);

	mq_tab_populate_tab(tab);

	tab->chrome = mq_tab_chrome_new(uri);
	tab->body = mq_tab_body_new(tab, uri);
	tab->web_view = mq_tab_body_get_web_view(tab->body);
	g_signal_connect(tab->web_view, "notify::favicon",
		G_CALLBACK(favicon_cb), tab);
	g_signal_connect(tab->web_view, "notify::title",
		G_CALLBACK(title_cb), tab);
	mq_tab_chrome_set_web_view(tab->chrome, tab->web_view);

	tab->container = gtk_box_new(GTK_ORIENTATION_VERTICAL, 0);
	gtk_box_pack_start(GTK_BOX(tab->container),
		mq_tab_chrome_get_container(tab->chrome), FALSE, FALSE, 0);
	gtk_box_pack_start(GTK_BOX(tab->container),
		mq_tab_body_get_container(tab->body), TRUE, TRUE, 0);

	return tab;
}

MqTab *
mq_tab_new(MqWindow *window, gchar *uri, MqTab *source)
{
	MqTab *tab;

	tab = init_non_root(window, uri);

	append_sibling(tab, source);

	mq_window_insert_tab(window, tab->container, tab->tab, tab->position);

	return tab;
}

MqTab *
mq_tab_new_relative(MqWindow *window, gchar *uri, MqTab *source)
{
	MqTab *tab;

	tab = init_non_root(window, uri);

	append_child(tab, source);

	mq_window_insert_tab(window, tab->container, tab->tab, tab->position);

	return tab;
}

MqTab *
mq_tab_new_root(void)
{
	MqTab *tab;

	tab = malloc(sizeof(*tab));
	tab->parent = NULL;
	tab->prev = NULL;
	tab->next = NULL;
	tab->first_child = tab->last_child = NULL;
	tab->position = 0;
	tab->tree_size = 1;

	return tab;
}

void
mq_tab_update_position(MqTab *tab, guint position)
{
	tab->position = position;
	update_tab_label(tab);
}

MqTab *
mq_tab_seek(MqTab *node, guint position)
{
	/* Skip forward to the containing subtree. */
	while (node && node->position + node->tree_size <= position) {
		node = node->next;
	}

	/* Check whether we've gone past the end of the tree. */
	if (!node) {
		return NULL;
	}

	/* Check whether the sibling we've reached is the node we want. */
	if (node->position == position) {
		return node;
	}

	/* Recurse down the subtree. */
	return mq_tab_seek(node->first_child, position);
}