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

#include "limox.h"


struct chat {
	GtkWidget* roster_item;       // the button in the roster list
	GtkWidget* chat_layout_box;   // the layout box of the chat page
	GtkWidget* chat_content_box;  // the content box of the chat page
	GtkWidget* text_entry;        // where new messages are typed
	struct chat* next;            // entry to support the linked list
};


// linked list of chats
static struct chat* chats = NULL;

// the GTK application is available as global variable
static GtkApplication* app;

// all GTK widgets are accessible in this file via global variables
static GtkWidget* window;
static GtkWidget* stack;

// connector page
static GtkStackPage* connector_page;
static GtkWidget* connector_box;
static GtkWidget* connector_jid_label;
static GtkWidget* connector_jid_entry;
static GtkWidget* connector_pwd_label;
static GtkWidget* connector_pwd_entry;
static GtkWidget* connector_button;

// roster page
static GtkStackPage* roster_page;
static GtkWidget* roster_layout_box;
static GtkWidget* roster_scrolled;
static GtkWidget* roster_content_box;
static GtkWidget* roster_button;


static void quit_cb(void) {
	limox_quit();
	g_application_quit(G_APPLICATION(app));
}

static void connect_cb(void) {

	const char* jid_text = gtk_editable_get_text(GTK_EDITABLE(connector_jid_entry));
	const char* pwd_text = gtk_editable_get_text(GTK_EDITABLE(connector_pwd_entry));

	gtk_stack_set_visible_child(GTK_STACK(stack), roster_layout_box);

	// just dummy output
	printf("Connecting with:\nJID: %s\nPWD: %s\n", jid_text, pwd_text);

	limox_connect(jid_text, pwd_text);
}

static void disconnect_cb(void) {

	gtk_stack_set_visible_child(GTK_STACK(stack), connector_box);

	// just dummy output
	printf("Disconnected!\n");

	limox_disconnect();
}

static void to_chat(GtkWidget* layout_box) {
	gtk_stack_set_visible_child(GTK_STACK(stack), layout_box);
}

static void to_roster(void) {
	gtk_stack_set_visible_child(GTK_STACK(stack), roster_layout_box);
}

void send_message(struct chat* chat) {

	// get recipient and message text
	const char* recipient = gtk_button_get_label(GTK_BUTTON(chat->roster_item));
	const char* text = gtk_editable_get_text(GTK_EDITABLE(chat->text_entry));

	// execute dummy XMPP send TODO
	printf("Sending to %s:\n> %s\n", recipient, text);

	// add message content to the chat
	GtkWidget* message = gtk_label_new(text);
	gtk_box_append(GTK_BOX(chat->chat_content_box), message);

	// clear text input
	GtkEntryBuffer* empty_buffer = gtk_entry_buffer_new("", 0);
	gtk_entry_set_buffer(GTK_ENTRY(chat->text_entry), empty_buffer);
}

void add_chat(char* jid) {

	// create chat struct and initialize
	struct chat* chat = malloc(sizeof(struct chat));
	chat->roster_item = gtk_button_new_with_label(jid);
	chat->chat_layout_box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 20);
	chat->chat_content_box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 5);
	chat->text_entry = gtk_entry_new();
	chat->next = NULL;

	// add chat page to stack
	gtk_stack_add_child(GTK_STACK(stack), chat->chat_layout_box);

	// add a button to go back to roster
	GtkWidget* back = gtk_button_new_with_label("back");
	gtk_box_append(GTK_BOX(chat->chat_layout_box), back);
	g_signal_connect_swapped(back, "clicked", G_CALLBACK(to_roster), NULL);

	// add a scrolled window to chat page
	GtkWidget* scrolled = gtk_scrolled_window_new();
	gtk_widget_set_vexpand(scrolled, TRUE);
	gtk_box_append(GTK_BOX(chat->chat_layout_box), scrolled);
	gtk_scrolled_window_set_child(GTK_SCROLLED_WINDOW(scrolled),
		chat->chat_content_box);

	// add text entry and send button to chat page
	gtk_box_append(GTK_BOX(chat->chat_layout_box), chat->text_entry);
	GtkWidget* send_button = gtk_button_new_with_label("send");
	gtk_box_append(GTK_BOX(chat->chat_layout_box), send_button);
	g_signal_connect_swapped(send_button, "clicked", G_CALLBACK(send_message),
		chat);

	// add chat to roster list
	gtk_box_append(GTK_BOX(roster_content_box), chat->roster_item);
	g_signal_connect_swapped(chat->roster_item, "clicked", G_CALLBACK(to_chat),
		chat->chat_layout_box);

	// append chat to linked list of chats
	struct chat* current = chats;
	while (true) {
		if (current == NULL) {
			chats = chat;
			break;
		} else if (current->next == NULL) {
			current->next = chat;
			break;
		} else {
			current = current->next;
		}
	}

}

void add_incoming_text_message(char* sender_jid, char* content) {

	// do not add message if list of chats is empty
	if (chats == NULL) {
		return;
	}

	// find chat with corresponding JID
	struct chat* chat = chats;
	while (true) {
		const char* jid = gtk_button_get_label(GTK_BUTTON(chat->roster_item));
		if (strcmp(jid, sender_jid) == 0) {
			break;  // this seems to be the correct chat
		} else if (chat->next == NULL) {
			return;  // no matching chat found - cannot add message
		} else {
			chat = chat->next;  // go to next chat in linked list
		}
	}

	// add given message content to the chat
	GtkWidget* message = gtk_label_new(content);
	gtk_box_append(GTK_BOX(chat->chat_content_box), message);

}

static void build_static_widgets(void) {

	// main window with stack
	window = gtk_window_new();
	gtk_window_set_title(GTK_WINDOW(window), "LimoX");
	gtk_window_set_default_size(GTK_WINDOW(window), 800, 600);
	stack = gtk_stack_new();
	gtk_window_set_child(GTK_WINDOW(window), stack);

	// connector page
	connector_box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 20);
	connector_page = gtk_stack_add_child(GTK_STACK(stack), connector_box);
	connector_jid_label = gtk_label_new("XMPP address (JID)");
	gtk_box_append(GTK_BOX(connector_box), connector_jid_label);
	connector_jid_entry = gtk_entry_new();
	gtk_box_append(GTK_BOX(connector_box), connector_jid_entry);
	connector_pwd_label = gtk_label_new("Password");
	gtk_box_append(GTK_BOX(connector_box), connector_pwd_label);
	connector_pwd_entry = gtk_password_entry_new();
	gtk_box_append(GTK_BOX(connector_box), connector_pwd_entry);
	connector_button = gtk_button_new_with_label("Connect");
	gtk_box_append(GTK_BOX(connector_box), connector_button);

	// roster page
	roster_layout_box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 20);
	roster_page = gtk_stack_add_child(GTK_STACK(stack), roster_layout_box);
	roster_button = gtk_button_new_with_label("Disconnect");
	gtk_box_append(GTK_BOX(roster_layout_box), roster_button);
	roster_scrolled = gtk_scrolled_window_new();
	gtk_widget_set_vexpand(roster_scrolled, TRUE);
	roster_content_box = gtk_box_new(GTK_ORIENTATION_VERTICAL, 10);
	gtk_scrolled_window_set_child(GTK_SCROLLED_WINDOW(roster_scrolled),
		roster_content_box);
	gtk_box_append(GTK_BOX(roster_layout_box), roster_scrolled);

	// TODO remove this
	// add dummy roster items
	for (int i=0; i<10; i++) {
		// char buffer[50];
		char* buffer = malloc(50*sizeof(char));
		sprintf(buffer, "contact-%d@example.com", i+1);
		add_chat(buffer);
	}

	// TODO just for debugging
	for (int i=0; i<20; i++) {
		add_incoming_text_message("contact-2@example.com", "Just a test.");
		// message = gtk_label_new("Test message");
		// gtk_box_append(GTK_BOX(chat->chat_content_box), message);
	}

}

static void activate(void) {

	build_static_widgets();

	// configure widgets
	gtk_window_set_application(GTK_WINDOW(window), app);
	g_signal_connect_swapped(window, "close-request", G_CALLBACK(quit_cb), app);
	g_signal_connect_swapped(
		connector_button, "clicked", G_CALLBACK(connect_cb), NULL);
	g_signal_connect_swapped(
		roster_button, "clicked", G_CALLBACK(disconnect_cb), NULL);

	gtk_widget_show(window);
}

static void idle_cb(void) {

	limox_run_once();

}

void gui_run(void) {

#ifdef GTK_SRCDIR
	g_chdir(GTK_SRCDIR);
#endif

	app = gtk_application_new("eu.xengineering.limox", G_APPLICATION_FLAGS_NONE);
	g_signal_connect(app, "activate", G_CALLBACK(activate), NULL);
	g_idle_add(G_SOURCE_FUNC(idle_cb), NULL);

	g_application_run(G_APPLICATION(app), 0, NULL);
	g_object_unref(app);

}

void gui_add_message(const char* sender_jid, const char* content) {

	printf("Received from %s:\n%s\n", sender_jid, content);
}

void* gui_add_roster_item(const char* jid, const char* sub, const char* name) {

	if (name) {
		printf("roster item: %s, %s, sub:%s\n", name, jid, sub);
	} else {
		printf("roster item: (no name), %s, sub:%s\n", jid, sub);
	}

	return NULL;  // TODO return pointer to GTK widget
}