/*
 * Tab body
 *
 * 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 <string.h>

#include <gtk/gtk.h>
#include <webkit2/webkit2.h>

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

#define WKCMA(ACTION) \
	WEBKIT_CONTEXT_MENU_ACTION_##ACTION

static void
menu_open_link_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	webkit_web_view_load_uri(body->web_view,
		webkit_hit_test_result_get_link_uri(body->hit_test_result));
}

static void
menu_open_link_tab_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	mq_tab_new_relative(
		webkit_hit_test_result_get_link_uri(body->hit_test_result),
		body->tab);
}

static void
menu_open_link_win_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	const gchar *uris[2] = {
		webkit_hit_test_result_get_link_uri(body->hit_test_result),
		NULL
	};
	mq_application_add_window(body->tab->application, uris);
}

static void
menu_open_image_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	webkit_web_view_load_uri(body->web_view,
		webkit_hit_test_result_get_image_uri(body->hit_test_result));
}

static void
menu_open_image_tab_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	mq_tab_new_relative(
		webkit_hit_test_result_get_image_uri(body->hit_test_result),
		body->tab);
}

static void
menu_open_image_win_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	const gchar *uris[2] = {
		webkit_hit_test_result_get_image_uri(body->hit_test_result),
		NULL
	};
	mq_application_add_window(body->tab->application, uris);
}

static void
menu_open_video_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	webkit_web_view_load_uri(body->web_view,
		webkit_hit_test_result_get_media_uri(body->hit_test_result));
}

static void
menu_open_video_tab_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	mq_tab_new_relative(
		webkit_hit_test_result_get_media_uri(body->hit_test_result),
		body->tab);
}

static void
menu_open_video_win_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	const gchar *uris[2] = {
		webkit_hit_test_result_get_media_uri(body->hit_test_result),
		NULL
	};
	mq_application_add_window(body->tab->application, uris);
}

static void
menu_open_audio_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	webkit_web_view_load_uri(body->web_view,
		webkit_hit_test_result_get_media_uri(body->hit_test_result));
}

static void
menu_open_audio_tab_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	mq_tab_new_relative(
		webkit_hit_test_result_get_media_uri(body->hit_test_result),
		body->tab);
}

static void
menu_open_audio_win_activate_cb(GtkAction __attribute__((unused)) *action,
	MqTabBody *body)
{
	const gchar *uris[2] = {
		webkit_hit_test_result_get_media_uri(body->hit_test_result),
		NULL
	};
	mq_application_add_window(body->tab->application, uris);
}

#define ITEM_DECLS \
	GtkAction             *action; \
	WebKitContextMenuItem *menu_item;
#define ITEM_DECLS_NO_CUSTOM \
	WebKitContextMenuItem *menu_item;
#define NEW_CUSTOM_ITEM(NAME, LABEL) \
	do { \
		/* Don't blame me; blame WebKitGTK+ for using GtkAction. */ \
		_Pragma("GCC diagnostic push") \
		_Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")\
		action = gtk_action_new(#NAME, (LABEL), NULL, NULL); \
		_Pragma("GCC diagnostic pop") \
		g_signal_connect(action, "activate", \
			G_CALLBACK(menu_##NAME##_activate_cb), body); \
		menu_item = webkit_context_menu_item_new(action); \
		webkit_context_menu_append(context_menu, menu_item); \
	} while (0)
#define NEW_STOCK_ITEM(STOCK) \
	do { \
		menu_item = webkit_context_menu_item_new_from_stock_action( \
			WEBKIT_CONTEXT_MENU_ACTION_##STOCK); \
		webkit_context_menu_append(context_menu, menu_item); \
	} while (0)
#define NEW_SEPARATOR_ITEM() \
	do { \
		webkit_context_menu_append(context_menu, \
			webkit_context_menu_item_new_separator()); \
	} while (0)
#define RESTORE_ITEMS(ITEMS) \
	do { \
		for (; ITEMS; ITEMS = ITEMS->next) { \
			webkit_context_menu_append(context_menu, ITEMS->data); \
			g_object_unref(ITEMS->data); \
		} \
	} while (0)

static void
context_menu_link_cb(WebKitContextMenu *context_menu, MqTabBody *body)
{
	ITEM_DECLS

	NEW_CUSTOM_ITEM(open_link,     "_Open Link");
	NEW_CUSTOM_ITEM(open_link_tab, "Open Link in New _Tab");
	NEW_CUSTOM_ITEM(open_link_win, "Open Link in New _Window");
	NEW_SEPARATOR_ITEM();                    /* --- */
	NEW_STOCK_ITEM(DOWNLOAD_LINK_TO_DISK);   /* _Download Linked File */
	NEW_STOCK_ITEM(COPY_LINK_TO_CLIPBOARD);  /* Copy Link Loc_ation */
}

static void
context_menu_image_cb(WebKitContextMenu *context_menu, MqTabBody *body)
{
	ITEM_DECLS

	NEW_CUSTOM_ITEM(open_image,     "Open _Image");
	NEW_CUSTOM_ITEM(open_image_tab, "Open Image in New Tab");
	NEW_CUSTOM_ITEM(open_image_win, "Open Image in New Window");
	NEW_SEPARATOR_ITEM();                         /* --- */
	NEW_STOCK_ITEM(DOWNLOAD_IMAGE_TO_DISK);       /* Sa_ve Image As */
	NEW_STOCK_ITEM(COPY_IMAGE_TO_CLIPBOARD);      /* Cop_y Image */
	NEW_STOCK_ITEM(COPY_IMAGE_URL_TO_CLIPBOARD);  /* Copy Image _Address */
}

static void
context_menu_media_cb(WebKitContextMenu *context_menu, GList *media_ctrl_items,
	GList *media_toggle_items, gboolean is_video, MqTabBody *body)
{
	ITEM_DECLS

	/* _Play/_Pause, _Mute */
	RESTORE_ITEMS(media_ctrl_items);
	/* _Toggle Media Controls, Toggle Media _Loop Playback, Switch Video to
	 * _Fullscreen */
	RESTORE_ITEMS(media_toggle_items);
	NEW_SEPARATOR_ITEM();  /* --- */
	if (is_video) {
		NEW_CUSTOM_ITEM(open_video,     "_Open Video");
		NEW_CUSTOM_ITEM(open_video_tab, "Open Video in New Tab");
		NEW_CUSTOM_ITEM(open_video_win, "Open Video in New Window");
		NEW_SEPARATOR_ITEM();  /* --- */
		NEW_STOCK_ITEM(DOWNLOAD_VIDEO_TO_DISK);  /* Download _Video */
		/* Cop_y Video Link Location */
		NEW_STOCK_ITEM(COPY_VIDEO_LINK_TO_CLIPBOARD);
	} else {
		NEW_CUSTOM_ITEM(open_audio,     "_Open Audio");
		NEW_CUSTOM_ITEM(open_audio_tab, "Open Audio in New Tab");
		NEW_CUSTOM_ITEM(open_audio_win, "Open Audio in New Window");
		NEW_SEPARATOR_ITEM();  /* --- */
		NEW_STOCK_ITEM(DOWNLOAD_AUDIO_TO_DISK);  /* Download _Audio */
		/* Cop_y Audio Link Location */
		NEW_STOCK_ITEM(COPY_AUDIO_LINK_TO_CLIPBOARD);
	}
}

static void
context_menu_editable_cb(WebKitContextMenu *context_menu, GList *edit_items,
	GList *input_items, MqTabBody __attribute__((unused)) *body)
{
	ITEM_DECLS_NO_CUSTOM

	RESTORE_ITEMS(edit_items);   /* Cu_t, _Copy, _Paste, _Delete */
	NEW_SEPARATOR_ITEM();        /* --- */
	NEW_STOCK_ITEM(SELECT_ALL);  /* Select _All */
	NEW_SEPARATOR_ITEM();        /* --- */
	RESTORE_ITEMS(input_items);  /* _Insert Unicode Character */
}
static void
context_menu_document_cb(WebKitContextMenu *context_menu, GList *nav_items,
	MqTabBody __attribute__((unused)) *body)
{
	ITEM_DECLS_NO_CUSTOM

	RESTORE_ITEMS(nav_items);    /* _Back, _Forward, _Stop, _Reload */
	NEW_SEPARATOR_ITEM();        /* --- */
	NEW_STOCK_ITEM(SELECT_ALL);  /* Select _All */
	NEW_SEPARATOR_ITEM();        /* --- */
	/* View Page Source */
}

#define PRESERVE_ITEM(ITEMS) \
	do { \
		g_object_ref(items->data); \
		ITEMS = g_list_prepend(ITEMS, items->data); \
	} while (0)

static gboolean
context_menu_cb(WebKitWebView __attribute__((unused)) *web_view,
	WebKitContextMenu *context_menu,
	GdkEvent __attribute__((unused)) *event,
	WebKitHitTestResult *hit_test_result, MqTabBody *body)
{
	GList                      *items;
	GList                      *nav_items;
	GList                      *edit_items;
	GList                      *input_items;
	GList                      *spell_items;
	GList                      *media_ctrl_items;
	GList                      *media_toggle_items;
	gboolean                    is_selection;
	gboolean                    is_video;
	WebKitContextMenuAction     stock_action;
	WebKitHitTestResultContext  context;
	gboolean                    context_handled;
	WebKitContextMenuItem      *menu_item;

	/* Get more hints about the context, since WebKit doesn't describe
	 * context very well in hit test results.  Also, preserve menu items
	 * that aren't easy to reproduce (e.g. the Unicode menu and spelling
	 * guesses). */
	items = webkit_context_menu_get_items(context_menu);
	nav_items          = NULL;
	edit_items         = NULL;
	input_items        = NULL;
	spell_items        = NULL;
	media_ctrl_items   = NULL;
	media_toggle_items = NULL;
	is_selection = FALSE;
	is_video = FALSE;
	for (; items; items = items->next) {
		stock_action = webkit_context_menu_item_get_stock_action(
			items->data);
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wswitch"
		switch (stock_action) {
			case WKCMA(GO_BACK):
			case WKCMA(GO_FORWARD):
			case WKCMA(STOP):
			case WKCMA(RELOAD):
				PRESERVE_ITEM(nav_items);
				break;
			case WKCMA(COPY):
				PRESERVE_ITEM(edit_items);
				is_selection = TRUE;
				break;
			case WKCMA(CUT):
			case WKCMA(PASTE):
			case WKCMA(DELETE):
				PRESERVE_ITEM(edit_items);
				break;
			case WKCMA(INPUT_METHODS):
			case WKCMA(UNICODE):
				PRESERVE_ITEM(input_items);
				break;
			case WKCMA(SPELLING_GUESS):
			case WKCMA(NO_GUESSES_FOUND):
			case WKCMA(IGNORE_SPELLING):
			case WKCMA(LEARN_SPELLING):
			case WKCMA(IGNORE_GRAMMAR):
				PRESERVE_ITEM(spell_items);
				break;
			case WKCMA(OPEN_VIDEO_IN_NEW_WINDOW):
			case WKCMA(COPY_VIDEO_LINK_TO_CLIPBOARD):
			case WKCMA(DOWNLOAD_VIDEO_TO_DISK):
				is_video = TRUE;
				break;
			case WKCMA(OPEN_AUDIO_IN_NEW_WINDOW):
			case WKCMA(COPY_AUDIO_LINK_TO_CLIPBOARD):
			case WKCMA(DOWNLOAD_AUDIO_TO_DISK):
				is_video = FALSE;
				break;
			case WKCMA(TOGGLE_MEDIA_CONTROLS):
			case WKCMA(TOGGLE_MEDIA_LOOP):
			case WKCMA(ENTER_VIDEO_FULLSCREEN):
				PRESERVE_ITEM(media_toggle_items);
				break;
			case WKCMA(MEDIA_PLAY):
			case WKCMA(MEDIA_PAUSE):
			case WKCMA(MEDIA_MUTE):
				PRESERVE_ITEM(media_ctrl_items);
				break;
		}
#pragma GCC diagnostic pop
	}
	nav_items          = g_list_reverse(nav_items);
	edit_items         = g_list_reverse(edit_items);
	input_items        = g_list_reverse(input_items);
	spell_items        = g_list_reverse(spell_items);
	media_ctrl_items   = g_list_reverse(media_ctrl_items);
	media_toggle_items = g_list_reverse(media_toggle_items);

	/* Clear the menu. */
	webkit_context_menu_remove_all(context_menu);

	/* Get the reported context (which isn't very descriptive) and save the
	 * hit test result for use by action callbacks. */
	context = webkit_hit_test_result_get_context(hit_test_result);
	if (body->hit_test_result) {
		g_object_unref(body->hit_test_result);
	}
	body->hit_test_result = hit_test_result;
	g_object_ref(body->hit_test_result);
	context_handled = FALSE;

	/* Build the context menu. */
	if (context & WEBKIT_HIT_TEST_RESULT_CONTEXT_LINK) {
		context_menu_link_cb(context_menu, body);
		context_handled = TRUE;
	}
	if (context & WEBKIT_HIT_TEST_RESULT_CONTEXT_IMAGE) {
		if (context_handled) {
			NEW_SEPARATOR_ITEM();
		}
		context_menu_image_cb(context_menu, body);
		context_handled = TRUE;
	}
	if (context & WEBKIT_HIT_TEST_RESULT_CONTEXT_MEDIA) {
		context_menu_media_cb(context_menu, media_ctrl_items,
			media_toggle_items, is_video, body);
		context_handled = TRUE;
	}
	if (context & WEBKIT_HIT_TEST_RESULT_CONTEXT_EDITABLE) {
		context_menu_editable_cb(context_menu, edit_items, input_items,
			body);
		context_handled = TRUE;
	}
	if (!context_handled &&
			context & WEBKIT_HIT_TEST_RESULT_CONTEXT_DOCUMENT) {
		if (is_selection) {
			RESTORE_ITEMS(edit_items);  /* _Copy */
			context_handled = TRUE;
		} else {
			context_menu_document_cb(context_menu, nav_items, body);
			context_handled = TRUE;
		}
	}
	if (context & WEBKIT_HIT_TEST_RESULT_CONTEXT_DOCUMENT) {
		if (context_handled) {
			NEW_SEPARATOR_ITEM();
		}
		NEW_STOCK_ITEM(INSPECT_ELEMENT);  /* Inspect Element */
	}

	/* Propagate the event further and show the context menu. */
	return FALSE;
}

static void
clipboard_text_recv_cb(GtkClipboard __attribute__((unused)) *clipboard,
	const gchar *text, MqTabBody *body)
{
	webkit_web_view_load_uri(body->web_view, text);
}

/* This callback is a hack to determine on middle mouse click whether to open a
 * link in a new tab or to load a URI from the primary clipboard.  The WebKit1
 * API provided webkit_web_view_get_hit_test_result() which would have been
 * easier. */
static void
mouse_target_changed_cb(WebKitWebView __attribute__((unused)) *web_view,
	WebKitHitTestResult *hit_test_result,
	guint __attribute__((unused)) modifiers,
	MqTabBody *body)
{
	body->mouse_target_hit_test_result = hit_test_result;
	g_object_ref(body->mouse_target_hit_test_result);
}

static gboolean
button_press_cb(WebKitWebView __attribute__((unused)) *web_view,
	GdkEvent *event, MqTabBody *body)
{
	WebKitHitTestResult *hit_test_result;
	GtkClipboard        *clipboard;

	/* Make sure this is a middle mouse button press event. */
	if (event->type != GDK_BUTTON_PRESS || event->button.button != 2) {
		return FALSE;
	}

	hit_test_result = body->mouse_target_hit_test_result;

	if (webkit_hit_test_result_context_is_link(hit_test_result)) {
		mq_tab_new_relative(
			webkit_hit_test_result_get_link_uri(hit_test_result),
			body->tab);
	} else if (webkit_hit_test_result_context_is_editable(hit_test_result)){
		/* Let WebKit handle pasting from the primary clipboard into an
		 * editable element. */
		g_object_unref(hit_test_result);
		return FALSE;
	} else {
		clipboard = gtk_clipboard_get(GDK_SELECTION_PRIMARY);
		gtk_clipboard_request_text(clipboard,
			(GtkClipboardTextReceivedFunc) clipboard_text_recv_cb,
			body);
	}

	g_object_unref(hit_test_result);

	return TRUE;
}

MqTabBody *
mq_tab_body_new(MqTab *tab, const gchar *uri)
{
	MqTabBody *body;
	gchar       *rw_uri;

	body = malloc(sizeof(*body));
	body->tab = tab;

	body->web_view = WEBKIT_WEB_VIEW(webkit_web_view_new());

	if (uri && g_str_has_prefix(uri, "about:")) {
		rw_uri = g_strconcat("mq-about:", uri + strlen("about:"), NULL);
	} else {
		rw_uri = g_strdup(uri);
	}
	if (rw_uri) {
		webkit_web_view_load_uri(body->web_view, rw_uri);
		g_free(rw_uri);
	}

	body->container = GTK_WIDGET(body->web_view);
	gtk_widget_set_vexpand(body->container, TRUE);
	/* FIXME: This doesn't seem to be working. */
	gtk_widget_grab_focus(body->container);

	body->hit_test_result = NULL;
	g_signal_connect(body->web_view, "context-menu",
		G_CALLBACK(context_menu_cb), body);
	g_signal_connect(body->web_view, "mouse-target-changed",
		G_CALLBACK(mouse_target_changed_cb), body);
	g_signal_connect(body->web_view, "button-press-event",
		G_CALLBACK(button_press_cb), body);

	return body;
}

GtkWidget *
mq_tab_body_get_container(MqTabBody *body)
{
	return body->container;
}

WebKitWebView *
mq_tab_body_get_web_view(MqTabBody *body)
{
	return body->web_view;
}