/**
 * [CSRD] Simple Chat Processor
 * 
 * Simple Chat Processor almost-compatible library for TF2.
 * Attempts to fix the one-recipient SayText2 messages, and does not depend on server-side
 * localization nonsense (i.e., everyone sees messages in their language).
 */
#pragma semicolon 1
#include <sourcemod>

#include <sdkhooks>

#pragma newdecls required

#define PLUGIN_VERSION "0.1.0"
public Plugin myinfo = {
	name = "[CSRD] Simple Chat Processor",
	author = "nosoop (based off of Simple Plugins' implementation)",
	description = "Simple Chat Processor almost-compatible library for TF2-specific fixes.",
	version = PLUGIN_VERSION,
	url = "https://git.csrd.science/"
}

#define PACKED_TOKEN_DELIMITER ":"

#define CHATFLAGS_INVALID		0b0000
#define CHATFLAGS_ALL			0b0001
#define CHATFLAGS_TEAM			0b0010
#define CHATFLAGS_SPEC			0b0100
#define CHATFLAGS_DEAD			0b1000

public APLRes AskPluginLoad2(Handle hPluginSelf, bool late, char[] error, int maxlen) {
	MarkNativeAsOptional("GetUserMessageType");
	CreateNative("GetMessageFlags", Native_GetMessageFlags);
	RegPluginLibrary("scp");
	
	return APLRes_Success;
}

// Holds player-unique messages sent in the current frame.
StringMap g_QueuedMessages[MAXPLAYERS+1];

Handle g_fwdOnChatMessage, g_fwdOnChatMessagePost;

int g_ChatFlags;

public void OnPluginStart() {
	UserMsg umSayText2 = GetUserMessageId("SayText2");
	if (umSayText2 != INVALID_MESSAGE_ID) {
		HookUserMessage(umSayText2, OnSayText2, true);
	} else {
		SetFailState("Game does not use SayText2.");
	}
	
	g_fwdOnChatMessage = CreateGlobalForward("OnChatMessage", ET_Hook, Param_CellByRef,
			Param_Cell, Param_String, Param_String);
	g_fwdOnChatMessagePost = CreateGlobalForward("OnChatMessage_Post", ET_Ignore, Param_Cell,
			Param_Cell, Param_String, Param_String);
	
	for (int i = 1; i < MaxClients; i++) {
		if (IsClientInGame(i)) {
			OnClientPutInServer(i);
		}
	}
}

public void OnClientPutInServer(int client) {
	g_QueuedMessages[client] = new StringMap();
	SDKHook(client, SDKHook_PostThink, OnClientThinkPost);
}

public void OnClientDisconnect(int client) {
	if (g_QueuedMessages[client]) {
		if (g_QueuedMessages[client].Size > 0) {
			// delete remaining queued messages, don't bother sending
			StringMapSnapshot messages = g_QueuedMessages[client].Snapshot();
			
			for (int m = 0; m < messages.Length; m++) {
				char packedMessage[192];
				messages.GetKey(m, packedMessage, sizeof(packedMessage));
				
				ArrayList clientList;
				g_QueuedMessages[client].GetValue(packedMessage, clientList);
				
				delete clientList;
			}
			g_QueuedMessages[client].Clear();
		}
		delete g_QueuedMessages[client];
	}
}

public Action OnSayText2(UserMsg id, Handle buffer, const int[] clients, int nClients,
		bool reliable, bool init) {
	BfRead bitbuf = view_as<BfRead>(buffer);
	
	int author = bitbuf.ReadByte();
	
	if (!author) {
		return Plugin_Continue;
	}
	
	bitbuf.ReadByte(); // bChat, unused?
	
	char localizationToken[32];
	bitbuf.ReadString(localizationToken, sizeof(localizationToken));
	
	if (StrContains(localizationToken, "TF_Chat_") == -1) {
		return Plugin_Continue;
	}
	
	if (!ParseChatMessageFlags(localizationToken)) {
		return Plugin_Continue;
	}
	
	char name[MAX_NAME_LENGTH];
	bitbuf.ReadString(name, sizeof(name));
	
	char message[128];
	bitbuf.ReadString(message, sizeof(message));
	
	/**
	 * Pack messages based on localization token and message.
	 * Any new similar usermessages in the same frame (matching message and flags) get their
	 * recipients added to the same entry.
	 */
	char packedMessage[192];
	Format(packedMessage, sizeof(packedMessage), "%s" ... PACKED_TOKEN_DELIMITER ... "%s",
			localizationToken, message);
	
	ArrayList recipients;
	
	if (!g_QueuedMessages[author].GetValue(packedMessage, recipients)) {
		recipients = new ArrayList();
		g_QueuedMessages[author].SetValue(packedMessage, recipients);
	}
	
	for (int i = 0; i < nClients; i++) {
		recipients.Push(clients[i]);
	}
	
	return Plugin_Handled;
}

public void OnClientThinkPost(int client) {
	/**
	 * Iterate through all queued messages from OnSayText2
	 */
	if (g_QueuedMessages[client].Size > 0) {
		StringMapSnapshot messages = g_QueuedMessages[client].Snapshot();
		
		for (int m = 0; m < messages.Length; m++) {
			char packedMessage[192], localizationToken[32], message[128];
			messages.GetKey(m, packedMessage, sizeof(packedMessage));
			
			ArrayList clientList;
			
			g_QueuedMessages[client].GetValue(packedMessage, clientList);
			
			// unpack localization and message from key
			strcopy(localizationToken, StrContains(packedMessage, PACKED_TOKEN_DELIMITER) + 1,
					packedMessage);
			strcopy(message, sizeof(message), packedMessage[strlen(localizationToken) + 1]);
			
			char name[MAX_NAME_LENGTH + 1];
			GetClientName(client, name, sizeof(name));
			
			// Prepare chat message flags.
			g_ChatFlags = ParseChatMessageFlags(localizationToken);
			
			// Forward call.
			Action forwardResult = ForwardOnChatMessage(client, clientList, name, sizeof(name),
					message, sizeof(message));
			
			// Proceed to display message on continue or changed, else drop message.
			if (forwardResult < Plugin_Handled) {
				// convert ArrayList to client array
				int clients[MAXPLAYERS + 1], nClients;
				for (int i = 0; i < clientList.Length; i++) {
					clients[nClients++] = clientList.Get(i);
				}
				
				SayText(client, clients, nClients, localizationToken, name, message);
				
				ForwardOnChatMessagePost(client, clientList, name, message);
			}
			delete clientList;
			
			g_ChatFlags = CHATFLAGS_INVALID;
		}
		delete messages;
		
		g_QueuedMessages[client].Clear();
	}
}

Action ForwardOnChatMessage(int &author, ArrayList clientList, char[] name, int nameLength,
		char[] message, int messageLength) {
	Action forwardResult;
	Call_StartForward(g_fwdOnChatMessage);
	Call_PushCellRef(author);
	Call_PushCell(clientList);
	Call_PushStringEx(name, nameLength,
			SM_PARAM_STRING_UTF8 | SM_PARAM_STRING_COPY, SM_PARAM_COPYBACK);
	Call_PushStringEx(message, messageLength,
			SM_PARAM_STRING_UTF8 | SM_PARAM_STRING_COPY, SM_PARAM_COPYBACK);
	
	int error = Call_Finish(forwardResult);
	
	if (error) {
		ThrowNativeError(error, "Forward failed");
		return Plugin_Stop;
	}
	return forwardResult;
}

void ForwardOnChatMessagePost(int author, ArrayList clientList, const char[] name,
		const char[] message) {
	Call_StartForward(g_fwdOnChatMessagePost);
	Call_PushCell(author);
	Call_PushCell(clientList);
	Call_PushString(name);
	Call_PushString(message);
	
	int error = Call_Finish();
	if (error) {
		ThrowNativeError(error, "Forward failed");
	}
}

public int Native_GetMessageFlags(Handle hPlugin, int argc) {
	return g_ChatFlags;
}

int ParseChatMessageFlags(const char[] localizationToken) {
	int chatFlags;
	if (StrContains(localizationToken, "all", false) != -1) {
		// send to all players, living and dead
		chatFlags |= CHATFLAGS_ALL;
	}
	if (StrContains(localizationToken, "team", false) != -1) {
		// send only to players on the same team
		chatFlags |= CHATFLAGS_TEAM;
	}
	if (StrContains(localizationToken, "spec", false) != -1) {
		// send only to players in spec
		chatFlags |= CHATFLAGS_SPEC;
	}
	if (StrContains(localizationToken, "dead", false) != -1) {
		// send to dead players and team members only
		chatFlags |= CHATFLAGS_DEAD;
	}
	return chatFlags;
}

void SayText(int author, int[] clients, int nClients,
		const char[] localizationToken, const char[] name, const char[] message) {
	Handle buffer = StartMessage("SayText2", clients, nClients,
			USERMSG_RELIABLE | USERMSG_BLOCKHOOKS);
	
	BfWrite bitbuf = view_as<BfWrite>(buffer);
	
	bitbuf.WriteByte(author);
	bitbuf.WriteByte(true);
	bitbuf.WriteString(localizationToken);
	bitbuf.WriteString(name);
	bitbuf.WriteString(message);
	
	EndMessage();
}