/*
 * Web view
 *
 * 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 "web-view.h"

#include <stdlib.h>
#include <string.h>

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

#include "config/config.h"
#include "notebook.h"
#include "tab-page.h"
#include "web-view-schemes/schemes.h"

struct _MqWebView {
	WebKitWebView           parent_instance;
	MqTabPage              *tab_page;
	MqWebViewScheme         scheme;
	MqWebViewSchemeMethods *scheme_methods;
	gchar                  *uri;
	MqConfig               *config;
	WebKitHitTestResult    *mouse_target_hit_test_result;
	guchar                 *data;
	gsize                   data_length;
};

enum {
	PROP_TAB_PAGE = 1,
	PROP_DISPLAY_URI,
	PROP_DATA,
	N_PROPERTIES
};

static GParamSpec *obj_properties[N_PROPERTIES] = {NULL,};

struct _MqWebViewClass {
	WebKitWebViewClass parent_class;
};

G_DEFINE_TYPE(MqWebView, mq_web_view, WEBKIT_TYPE_WEB_VIEW)

static void
load_changed_cb(MqWebView *web_view, WebKitLoadEvent G_GNUC_UNUSED load_event)
{
	g_free(web_view->data);
	web_view->data = NULL;
}

static gboolean
context_menu_cb(MqWebView *web_view, WebKitContextMenu *context_menu,
	GdkEvent *event, WebKitHitTestResult *hit_test_result)
{
	return web_view->scheme_methods->context_menu(web_view,
		&web_view->scheme, context_menu, event, hit_test_result);
}

static void
uri_cb(MqWebView *web_view, GParamSpec G_GNUC_UNUSED *param_spec)
{
	const gchar *uri;

	if (web_view->uri) {
		g_free(web_view->uri);
	}

	uri = webkit_web_view_get_uri(WEBKIT_WEB_VIEW(web_view));

	mq_web_view_scheme_set_methods(web_view, &web_view->scheme,
		&web_view->scheme_methods, uri);

	web_view->uri = web_view->scheme_methods->display_uri(
		web_view, &web_view->scheme, uri);

	g_object_notify_by_pspec(G_OBJECT(web_view),
		obj_properties[PROP_DISPLAY_URI]);
}

static void
clipboard_text_recv_cb(GtkClipboard G_GNUC_UNUSED *clipboard,
	const gchar *text, MqWebView *web_view)
{
	mq_web_view_load_uri(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 *wk_web_view,
	WebKitHitTestResult *hit_test_result, guint G_GNUC_UNUSED modifiers)
{
	MqWebView *web_view;

	web_view = MQ_WEB_VIEW(wk_web_view);

	web_view->mouse_target_hit_test_result = hit_test_result;
	g_object_ref(web_view->mouse_target_hit_test_result);
}

static gboolean
button_press_cb(GtkWidget *widget, GdkEventButton *event)
{
	MqWebView           *web_view;
	WebKitHitTestResult *hit_test_result;
	GtkClipboard        *clipboard;

	web_view = MQ_WEB_VIEW(widget);

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

	hit_test_result = web_view->mouse_target_hit_test_result;

	if (webkit_hit_test_result_context_is_link(hit_test_result)) {
		mq_notebook_insert_child(
			MQ_NOTEBOOK(gtk_widget_get_parent(
					GTK_WIDGET(web_view->tab_page))),
			webkit_hit_test_result_get_link_uri(hit_test_result),
			web_view->tab_page,
			!mq_config_get_boolean(web_view->config,
				"tabs.background"));
	} 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,
			web_view);
	}

	g_object_unref(hit_test_result);

	return TRUE;
}

static gboolean
decide_response_policy(MqWebView G_GNUC_UNUSED *web_view,
	WebKitResponsePolicyDecision *decision)
{
	if (webkit_response_policy_decision_is_mime_type_supported(decision)) {
		webkit_policy_decision_use(WEBKIT_POLICY_DECISION(decision));
	} else {
		webkit_policy_decision_download(
			WEBKIT_POLICY_DECISION(decision));
	}
	return TRUE;
}

static gboolean
decide_policy_cb(MqWebView *web_view, WebKitPolicyDecision *decision,
	WebKitPolicyDecisionType decision_type)
{
	switch (decision_type) {
		case WEBKIT_POLICY_DECISION_TYPE_NAVIGATION_ACTION:
			/* TODO */
			return FALSE;
		case WEBKIT_POLICY_DECISION_TYPE_NEW_WINDOW_ACTION:
			/* TODO */
			return FALSE;
		case WEBKIT_POLICY_DECISION_TYPE_RESPONSE:
			return decide_response_policy(web_view,
				WEBKIT_RESPONSE_POLICY_DECISION(decision));
		default:
			return FALSE;
	}
}

static void
constructed(GObject *object)
{
	MqWebView *web_view;
	gchar     *new_tab_page;

	if (G_OBJECT_CLASS(mq_web_view_parent_class)->constructed) {
		G_OBJECT_CLASS(mq_web_view_parent_class)->constructed(object);
	}

	web_view = MQ_WEB_VIEW(object);

	web_view->config = mq_application_get_config(
		mq_tab_page_get_application(web_view->tab_page));

	if (!web_view->uri) {
		new_tab_page = mq_config_get_string(web_view->config,
			"tabs.new");
		if (g_strcmp0(new_tab_page, "home") == 0) {
			mq_web_view_load_uri(web_view, mq_config_get_string(
					web_view->config, "tabs.home"));
		} else if (g_strcmp0(new_tab_page, "blank") == 0) {
			/* Don't load any URI. */
		} else {
			g_assert_not_reached();
		}
	}

	mq_web_view_zoom_reset(web_view);

	gtk_widget_set_vexpand(GTK_WIDGET(web_view), TRUE);
}

static void
finalize(GObject *object)
{
	MqWebView *web_view;

	web_view = MQ_WEB_VIEW(object);

	g_free(web_view->uri);
	g_free(web_view->data);

	G_OBJECT_CLASS(mq_web_view_parent_class)->finalize(object);
}

static void
get_property(GObject *object, guint property_id, GValue *value,
	GParamSpec *param_spec)
{
	MqWebView *web_view;

	web_view = MQ_WEB_VIEW(object);

	switch (property_id) {
		case PROP_TAB_PAGE:
			g_value_set_object(value, web_view->tab_page);
			break;
		case PROP_DISPLAY_URI:
			g_value_set_string(value, web_view->uri);
			break;
		case PROP_DATA:
			g_value_set_pointer(value,
				mq_web_view_get_data(web_view, NULL));
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id,
				param_spec);
			break;
	}
}

static void
set_property(GObject *object, guint property_id, const GValue *value,
	GParamSpec *param_spec)
{
	MqWebView *web_view;

	web_view = MQ_WEB_VIEW(object);

	switch (property_id) {
		case PROP_TAB_PAGE:
			web_view->tab_page = g_value_get_object(value);
			break;
		case PROP_DISPLAY_URI:
			mq_web_view_load_uri(web_view,
				g_value_get_string(value));
			break;
		default:
			G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id,
				param_spec);
			break;
	}
}

static void
mq_web_view_class_init(MqWebViewClass *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS(klass);

	object_class->constructed  = constructed;
	object_class->finalize     = finalize;
	object_class->get_property = get_property;
	object_class->set_property = set_property;

	obj_properties[PROP_TAB_PAGE] = g_param_spec_object(
		"tab-page",
		"MqTabPage",
		"The parent MqTabPage instance",
		MQ_TYPE_TAB_PAGE,
		G_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY |
		G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB);
	obj_properties[PROP_DISPLAY_URI] = g_param_spec_string(
		"display-uri",
		"URI",
		"The current active URI of the Web view, "
			"with \"mq-about:\" rewritten to \"about:\"",
		"",
		G_PARAM_READWRITE |
		G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB);
	obj_properties[PROP_DATA] = g_param_spec_pointer(
		"data",
		"Resource data",
		"The main resource's data",
		G_PARAM_READABLE |
		G_PARAM_STATIC_NICK | G_PARAM_STATIC_BLURB);
	g_object_class_install_properties(object_class, N_PROPERTIES,
		obj_properties);
}

static void
mq_web_view_init(MqWebView *web_view)
{
	g_signal_connect(web_view, "load-changed",
		G_CALLBACK(load_changed_cb), NULL);
	g_signal_connect(web_view, "context-menu",
		G_CALLBACK(context_menu_cb), NULL);
	g_signal_connect(web_view, "notify::uri",
		G_CALLBACK(uri_cb), NULL);
	g_signal_connect(web_view, "mouse-target-changed",
		G_CALLBACK(mouse_target_changed_cb), NULL);
	g_signal_connect(web_view, "button-press-event",
		G_CALLBACK(button_press_cb), NULL);
	g_signal_connect(web_view, "decide-policy",
		G_CALLBACK(decide_policy_cb), NULL);
}

MqWebView *
mq_web_view_new(MqTabPage *tab_page, const gchar *uri)
{
	return g_object_new(MQ_TYPE_WEB_VIEW,
		"tab-page", tab_page,  /* TODO: Use gtk_widget_get_parent()? */
		"display-uri", uri,
		"web-context", webkit_web_context_get_default(),
		NULL);
}

MqWebViewScheme *
mq_web_view_get_scheme(MqWebView *web_view)
{
	return &web_view->scheme;
}

MqConfig *
mq_web_view_get_config(MqWebView *web_view)
{
	return web_view->config;
}

MqTabPage *
mq_web_view_get_tab_page(MqWebView *web_view)
{
	return web_view->tab_page;
}

const gchar *
mq_web_view_get_uri(MqWebView *web_view)
{
	return web_view->uri;
}

void
mq_web_view_load_uri(MqWebView *web_view, const gchar *uri)
{

	mq_web_view_scheme_set_methods(web_view, &web_view->scheme,
		&web_view->scheme_methods, uri);

	if (!uri) {
		/* Happens during object construction. */
		return;
	}

	if (web_view->uri) {
		g_free(web_view->uri);
	}

	web_view->uri = web_view->scheme_methods->rewrite_uri(
		web_view, &web_view->scheme, uri);
	webkit_web_view_load_uri(WEBKIT_WEB_VIEW(web_view),
		web_view->uri);

	g_object_notify_by_pspec(G_OBJECT(web_view),
		obj_properties[PROP_DISPLAY_URI]);
}

static void
get_data_cb(WebKitWebResource *resource, GAsyncResult *result,
	MqWebView *web_view)
{
	web_view->data = webkit_web_resource_get_data_finish(resource, result,
		&web_view->data_length, NULL);  /* TODO: Error handling? */

	g_object_notify_by_pspec(G_OBJECT(web_view),
		obj_properties[PROP_DATA]);
}

guchar *
mq_web_view_get_data(MqWebView *web_view, gsize *length)
{
	if (!web_view->data) {
		webkit_web_resource_get_data(webkit_web_view_get_main_resource(
				WEBKIT_WEB_VIEW(web_view)),
			NULL, (GAsyncReadyCallback) get_data_cb, web_view);
	}
	if (length) {
		*length = web_view->data_length;
	}
	return web_view->data;
}

void
mq_web_view_zoom_in(MqWebView *web_view)
{
	gdouble zoom_level;

	zoom_level = webkit_web_view_get_zoom_level(WEBKIT_WEB_VIEW(web_view));
	zoom_level += 0.1;
	if (zoom_level < 0) {
		zoom_level = G_MAXDOUBLE;
	}
	webkit_web_view_set_zoom_level(WEBKIT_WEB_VIEW(web_view), zoom_level);
}

void
mq_web_view_zoom_out(MqWebView *web_view)
{
	gdouble zoom_level;

	zoom_level = webkit_web_view_get_zoom_level(WEBKIT_WEB_VIEW(web_view));
	zoom_level -= 0.1;
	if (zoom_level < 0) {
		zoom_level = 0;
	}
	webkit_web_view_set_zoom_level(WEBKIT_WEB_VIEW(web_view), zoom_level);
}

void
mq_web_view_zoom_reset(MqWebView *web_view)
{
	gdouble zoom_level;

	zoom_level = mq_config_get_double(web_view->config, "zoom.default");
	webkit_web_view_set_zoom_level(WEBKIT_WEB_VIEW(web_view), zoom_level);
}

void
mq_web_view_add_html_mhtml_file_chooser_filters(GtkFileChooser *chooser)
{
	GtkFileFilter *filter;

	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter, "All files");
	gtk_file_filter_add_pattern(filter, "*");
	gtk_file_chooser_add_filter(chooser, filter);

	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter, "All Web pages");
	gtk_file_filter_add_pattern(filter, "*.htm");
	gtk_file_filter_add_pattern(filter, "*.html");
	gtk_file_filter_add_pattern(filter, "*.mht");
	gtk_file_filter_add_pattern(filter, "*.mhtm");
	gtk_file_filter_add_pattern(filter, "*.mhtml");
	gtk_file_chooser_add_filter(chooser, filter);

	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter, "HTML documents (*.htm, *.html)");
	gtk_file_filter_add_pattern(filter, "*.htm");
	gtk_file_filter_add_pattern(filter, "*.html");
	gtk_file_chooser_add_filter(chooser, filter);

	filter = gtk_file_filter_new();
	gtk_file_filter_set_name(filter,
		"MHTML documents (*.mht, *.mhtm, *.mhtml)");
	gtk_file_filter_add_pattern(filter, "*.mht");
	gtk_file_filter_add_pattern(filter, "*.mhtm");
	gtk_file_filter_add_pattern(filter, "*.mhtml");
	gtk_file_chooser_add_filter(chooser, filter);
}

static void
open_response_cb(GtkWidget *dialog, gint response_id, MqWebView *web_view)
{
	gchar *dir;
	gchar *filename;
	gchar *uri;

	if (response_id == GTK_RESPONSE_ACCEPT) {
		dir = gtk_file_chooser_get_current_folder(
			GTK_FILE_CHOOSER(dialog));
		if (dir) {
			mq_config_set_string(web_view->config,
				"directories.open-file", dir);
			g_free(dir);
			mq_config_save(web_view->config);
		}
		filename = gtk_file_chooser_get_filename(
			GTK_FILE_CHOOSER(dialog));
		uri = g_strconcat("file://", filename, NULL);
		g_free(filename);
		webkit_web_view_load_uri(WEBKIT_WEB_VIEW(web_view), uri);
		g_free(uri);
	}

	gtk_widget_destroy(dialog);
}

void
mq_web_view_open(MqWebView *web_view)
{
	GtkWidget *dialog;
	GtkFileChooser *chooser;
	gchar          *dir;

	dialog = gtk_file_chooser_dialog_new("Open File",
		GTK_WINDOW(mq_tab_page_get_window(web_view->tab_page)),
		GTK_FILE_CHOOSER_ACTION_OPEN,
		"_Cancel", GTK_RESPONSE_CANCEL,
		"_Open",   GTK_RESPONSE_ACCEPT,
		NULL);
	chooser = GTK_FILE_CHOOSER(dialog);

	dir = mq_config_get_string(web_view->config, "directories.open-file");
	if (dir && dir[0]) {
		gtk_file_chooser_set_current_folder(chooser, dir);
	}
	/* TODO: Consider setting chooser's folder from current file-scheme URI,
	 * if any. */
	g_free(dir);

	mq_web_view_add_html_mhtml_file_chooser_filters(chooser);

	g_signal_connect(dialog, "response",
		G_CALLBACK(open_response_cb), web_view);
	gtk_widget_show_all(dialog);
}

void
mq_web_view_save(MqWebView *web_view)
{
	web_view->scheme_methods->save_file(web_view, &web_view->scheme);
}

void
mq_web_view_grab_focus(MqWebView *web_view)
{
	gtk_widget_grab_focus(GTK_WIDGET(web_view));
}