// SONIC ROBO BLAST 2 KART
//-----------------------------------------------------------------------------
// Copyright (C) 2018-2020 by Sally "TehRealSalt" Cochenour.
// Copyright (C) 2018-2020 by Kart Krew.
//
// This program is free software distributed under the
// terms of the GNU General Public License, version 2.
// See the 'LICENSE' file for more details.
//-----------------------------------------------------------------------------
/// \file  discord.h
/// \brief Discord Rich Presence handling

#ifdef HAVE_DISCORDRPC

#ifdef HAVE_CURL
#include <curl/curl.h>
#endif

#include "i_system.h"
#include "d_clisrv.h"
#include "d_netcmd.h"
#include "i_net.h"
#include "g_game.h"
#include "p_tick.h"
#include "m_menu.h" // gametype_cons_t
#include "r_things.h" // skins
#include "mserv.h" // ms_RoomId

#include "discord.h"
#include "doomdef.h"

// Feel free to provide your own, if you care enough to create another Discord app for this :P
#define DISCORD_APPID "503531144395096085"

consvar_t cv_discordrp = {"discordrp", "On", CV_SAVE|CV_CALL, CV_OnOff, DRPC_UpdatePresence, 0, NULL, NULL, 0, 0, NULL};

#ifdef HAVE_CURL
struct SelfIPbuffer
{
	CURL *curl;
	char *pointer;
	size_t length;
};

#define IP_SIZE 16
static char self_ip[IP_SIZE];
#endif

/*--------------------------------------------------
	static void DRPC_HandleReady(const DiscordUser *user)

		Handler function, ran when the game connects to Discord.

	Input Arguments:-
		user - Struct containing Discord user info.

	Return:-
		None
--------------------------------------------------*/
static void DRPC_HandleReady(const DiscordUser *user)
{
	CONS_Printf("Discord: connected to %s#%s - %s\n", user->username, user->discriminator, user->userId);
}

/*--------------------------------------------------
	static void DRPC_HandleDisconnect(int err, const char *msg)

		Handler function, ran when disconnecting from Discord.

	Input Arguments:-
		err - Error type
		msg - Error message

	Return:-
		None
--------------------------------------------------*/
static void DRPC_HandleDisconnect(int err, const char *msg)
{
	CONS_Printf("Discord: disconnected (%d: %s)\n", err, msg);
}

/*--------------------------------------------------
	static void DRPC_HandleError(int err, const char *msg)

		Handler function, ran when Discord outputs an error.

	Input Arguments:-
		err - Error type
		msg - Error message

	Return:-
		None
--------------------------------------------------*/
static void DRPC_HandleError(int err, const char *msg)
{
	CONS_Alert(CONS_WARNING, "Discord error (%d: %s)\n", err, msg);
}

/*--------------------------------------------------
	static void DRPC_HandleJoin(const char *secret)

		Handler function, ran when Discord wants to
		connect a player to the game via a channel invite
		or a join request.

	Input Arguments:-
		secret - Value that links you to the server.

	Return:-
		None
--------------------------------------------------*/
static void DRPC_HandleJoin(const char *secret)
{
	CONS_Printf("Connecting to %s via Discord\n", secret);
	COM_BufAddText(va("connect \"%s\"\n", secret));
}

/*--------------------------------------------------
	void DRPC_Init(void)

		See header file for description.
--------------------------------------------------*/
void DRPC_Init(void)
{
	DiscordEventHandlers handlers;
	memset(&handlers, 0, sizeof(handlers));

	handlers.ready = DRPC_HandleReady;
	handlers.disconnected = DRPC_HandleDisconnect;
	handlers.errored = DRPC_HandleError;
	handlers.joinGame = DRPC_HandleJoin;

	Discord_Initialize(DISCORD_APPID, &handlers, 1, NULL);
	I_AddExitFunc(Discord_Shutdown);
	DRPC_UpdatePresence();
}

#ifdef HAVE_CURL
/*--------------------------------------------------
	static size_t DRPC_WriteServerIP(char *s, size_t size, size_t n, void *userdata)

		Writing function for use with curl. Only intended to be used with simple text.

	Input Arguments:-
		s - Data to write
		size - Always 1.
		n - Length of data
		userdata - Passed in from CURLOPT_WRITEDATA, intended to be SelfIPbuffer

	Return:-
		Number of bytes wrote in this pass.
--------------------------------------------------*/
static size_t DRPC_WriteServerIP(char *s, size_t size, size_t n, void *userdata)
{
	struct SelfIPbuffer *buffer;
	size_t newlength;

	buffer = userdata;

	newlength = buffer->length + size*n;
	buffer->pointer = realloc(buffer->pointer, newlength+1);

	memcpy(buffer->pointer + buffer->length, s, size*n);

	buffer->pointer[newlength] = '\0';
	buffer->length = newlength;

	return size*n;
}
#endif

/*--------------------------------------------------
	static const char *DRPC_GetServerIP(void)

		Retrieves the IP address of the server that you're
		connected to. Will attempt to use curl for getting your
		own IP address, if it's not yours.
--------------------------------------------------*/
static const char *DRPC_GetServerIP(void)
{
	const char *address; 

	// If you're connected
	if (I_GetNodeAddress && (address = I_GetNodeAddress(servernode)) != NULL)
	{
		if (strcmp(address, "self"))
		{
			// We're not the server, so we could successfully get the IP!
			// No need to do anything else :)
			return address; 
		}
	}

#ifdef HAVE_CURL
	// This is a little bit goofy, but
	// there's practically no good way to get your own public IP address,
	// so we've gotta break out curl for this :V
	if (!self_ip[0])
	{
		CURL *curl;

		curl_global_init(CURL_GLOBAL_ALL);
		curl = curl_easy_init();

		if (curl)
		{
			// The API to get your public IP address from.
			// Picked because it's stupid simple and it's been up for a long time.
			const char *api = "http://ip4only.me/api/"; 

			struct SelfIPbuffer buffer;
			CURLcode success;

			buffer.length = 0;
			buffer.pointer = malloc(buffer.length+1);
			buffer.pointer[0] = '\0';

			curl_easy_setopt(curl, CURLOPT_URL, api);
			curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, DRPC_WriteServerIP);
			curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);

			success = curl_easy_perform(curl);

			if (success == CURLE_OK)
			{
				char *tmp;
				tmp = strtok(buffer.pointer, ",");

				if (!strcmp(tmp, "IPv4")) // ensure correct type of IP
				{
					tmp = strtok(NULL, ",");
					strncpy(self_ip, tmp, IP_SIZE); // Yay, we have the IP :)
				}
			}

			free(buffer.pointer);
			curl_easy_cleanup(curl);
		}
	}

	if (self_ip[0])
		return self_ip;
	else
#endif
		return NULL; // Could not get your IP for whatever reason, so we cannot do Discord invites
}

/*--------------------------------------------------
	void DRPC_UpdatePresence(void)

		See header file for description.
--------------------------------------------------*/
void DRPC_UpdatePresence(void)
{
	char mapimg[8+1];
	char mapname[5+21+21+2+1];

	char charimg[4+SKINNAMESIZE+1];
	char charname[11+SKINNAMESIZE+1];

	DiscordRichPresence discordPresence;
	memset(&discordPresence, 0, sizeof(discordPresence));

	if (!cv_discordrp.value)
	{
		// User doesn't want to show their game information, so update with empty presence.
		// This just shows that they're playing SRB2Kart. (If that's too much, then they should disable game activity :V)
		Discord_UpdatePresence(&discordPresence);
		return;
	}

	// Server info
	if (netgame)
	{
		const char *join;

		switch (ms_RoomId)
		{
			case -1: discordPresence.state = "Private"; break; // Private server
			case 33: discordPresence.state = "Standard"; break;
			case 28: discordPresence.state = "Casual"; break;
			case 38: discordPresence.state = "Custom Gametypes"; break;
			case 31: discordPresence.state = "OLDC"; break;
			default: discordPresence.state = "Unknown Room"; break; // HOW
		}

		discordPresence.partyId = server_context; // Thanks, whoever gave us Mumble support, for implementing the EXACT thing Discord wanted for this field!
		discordPresence.partySize = D_NumPlayers(); // Players in server
		discordPresence.partyMax = cv_maxplayers.value; // Max players (TODO: another variable should hold this, so that maxplayers doesn't have to be a netvar)

		// Grab the host's IP for joining.
		if (cv_allownewplayer.value && ((join = DRPC_GetServerIP()) != NULL))
			discordPresence.joinSecret = join;
	}
	else
	{
		// Offline info
		if (Playing())
			discordPresence.state = "Offline";
		else if (demo.playback && !demo.title)
			discordPresence.state = "Watching Replay";
		else
			discordPresence.state = "Menu";
	}

	// Gametype info
	if (gamestate == GS_LEVEL || gamestate == GS_INTERMISSION || gamestate == GS_VOTING)
	{
		if (modeattacking)
			discordPresence.details = "Time Attack";
		else
			discordPresence.details = gametype_cons_t[gametype].strvalue;
	}

	if (gamestate == GS_LEVEL || gamestate == GS_INTERMISSION) // Map info
	{
		if ((gamemap >= 1 && gamemap <= 60) // supported race maps
			|| (gamemap >= 136 && gamemap <= 164)) // supported battle maps
		{
			snprintf(mapimg, 8, "%s", G_BuildMapName(gamemap));
			strlwr(mapimg);
			discordPresence.largeImageKey = mapimg; // Map image
		}
		else if (mapheaderinfo[gamemap-1]->menuflags & LF2_HIDEINMENU)
		{
			// Hell map, use the method that got you here :P
			discordPresence.largeImageKey = "maphell";
		}
		else
		{
			// This is probably a custom map!
			discordPresence.largeImageKey = "mapcustom";
		}

		if (mapheaderinfo[gamemap-1]->menuflags & LF2_HIDEINMENU)
		{
			// Hell map, hide the name
			discordPresence.largeImageText = "Map: ???";
		}
		else
		{
			snprintf(mapname, 48, "Map: %s%s%s",
				mapheaderinfo[gamemap-1]->lvlttl,
				(strlen(mapheaderinfo[gamemap-1]->zonttl) > 0) ? va(" %s",mapheaderinfo[gamemap-1]->zonttl) : // SRB2kart
				((mapheaderinfo[gamemap-1]->levelflags & LF_NOZONE) ? "" : " Zone"),
				(strlen(mapheaderinfo[gamemap-1]->actnum) > 0) ? va(" %s",mapheaderinfo[gamemap-1]->actnum) : "");
			discordPresence.largeImageText = mapname; // Map name
		}

		if (Playing())
		{
			const time_t currentTime = time(NULL);
			const time_t mapTimeStart = currentTime - ((leveltime + (modeattacking ? starttime : 0)) / TICRATE);

			discordPresence.startTimestamp = mapTimeStart;

			if (timelimitintics > 0)
			{
				const time_t mapTimeEnd = mapTimeStart + ((timelimitintics + starttime + 1) / TICRATE);
				discordPresence.endTimestamp = mapTimeEnd;
			}
		}
	}
	else if (gamestate == GS_VOTING)
	{
		discordPresence.largeImageKey = (G_BattleGametype() ? "miscredplanet" : "miscblueplanet");
		discordPresence.largeImageText = "Voting";
	}
	else
	{
		discordPresence.largeImageKey = "misctitle";
		discordPresence.largeImageText = "Title Screen";
	}

	// Character info
	if (Playing() && playeringame[consoleplayer] && !players[consoleplayer].spectator)
	{
		// Supported skin names
		static const char *supportedSkins[] = {
			// base game
			"sonic",
			"tails",
			"knuckles",
			"eggman",
			"metalsonic",
			// bonus chars
			"flicky",
			"motobug",
			"amy",
			"mighty",
			"ray",
			"espio",
			"vector",
			"chao",
			"gamma",
			"chaos",
			"shadow",
			"rouge",
			"herochao",
			"darkchao",
			"cream",
			"omega",
			"blaze",
			"silver",
			"wonderboy",
			"arle",
			"nights",
			"sakura",
			"ulala",
			"beat",
			"vyse",
			"aiai",
			"kiryu",
			"aigis",
			"miku",
			"doom",
			NULL
		};

		boolean customChar = true;
		UINT8 checkSkin = 0;

		// Character image
		while (supportedSkins[checkSkin] != NULL)
		{
			if (!strcmp(skins[players[consoleplayer].skin].name, supportedSkins[checkSkin]))
			{
				snprintf(charimg, 21, "char%s", supportedSkins[checkSkin]);
				discordPresence.smallImageKey = charimg;
				customChar = false;
				break;
			}

			checkSkin++;
		}

		if (customChar == true)
		{
			// Use the custom character icon!
			discordPresence.smallImageKey = "charcustom";
		}

		snprintf(charname, 28, "Character: %s", skins[players[consoleplayer].skin].realname);
		discordPresence.smallImageText = charname; // Character name
	}

	Discord_UpdatePresence(&discordPresence);
}

#endif