ppsspp/Core/Debugger/WebSocket/WebSocketUtils.h

// Copyright (c) 2018- PPSSPP Project.

// This program 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, version 2.0 or later versions.

// This program 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 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.

#pragma once

#include "ppsspp_config.h"

#include <string>

#include "Common/Log.h"
#include "Common/Data/Format/JSONReader.h"
#include "Common/Data/Format/JSONWriter.h"
#include "Common/Net/WebsocketServer.h"

#if PPSSPP_PLATFORM(UWP)
// Enum name overlapped with UWP macro, quick hack to disable it
#undef OPTIONAL
#endif

using namespace json;

struct WebSocketClientInfo {
	WebSocketClientInfo() = default;

	std::string name;
	std::string version;
	std::map<std::string, bool> disallowed;
	// Whether to send a "deferred" event for requests that only finish later. Off by default,
	// and it has to stay that way: an extra message would break a client that correlates purely
	// by ticket, or one that waits for the bare event name a resume or a button press answers
	// with. See client.config.set.
	bool acknowledgeDeferred = false;
};

// Sent, if the client asked for it, when a handler accepted a request but arranged to finish it
// later - a resume, a step, a button held for some frames. Deliberately not named after the
// request: the event that reports the actual outcome uses that name, and for input.buttons.press
// it carries the same ticket too, so anything less distinct would be impossible to tell apart.
// replyFollows says that outcome is a reply carrying the request's ticket (see ReplyLater()).
struct DebuggerDeferredEvent {
	DebuggerDeferredEvent(const char *n, const JsonGet data, bool replyFollows) : name(n), replyFollows(replyFollows) {
		const JsonNode *value = data ? data.get("ticket") : nullptr;
		if (value)
			ticketRaw = json_stringify(value);
	}

	const char *name;
	bool replyFollows;
	std::string ticketRaw;

	operator std::string() const {
		JsonWriter j;
		j.begin();
		j.writeString("event", "deferred");
		j.writeString("for", name);
		if (replyFollows) {
			j.writeBool("replyFollows", true);
		}
		if (!ticketRaw.empty()) {
			j.writeRaw("ticket", ticketRaw);
		}
		j.end();
		return j.str();
	}
};

struct DebuggerErrorEvent {
	DebuggerErrorEvent(const std::string m, LogLevel l, const JsonGet data = JsonValue(JSON_NULL))
		: message(m), level(l) {
		// Need to format right away, before it's out of scope.
		if (data) {
			const JsonNode *value = data.get("ticket");
			if (value)
				ticketRaw = json_stringify(value);
		}
	}

	std::string message;
	LogLevel level;
	std::string ticketRaw;

	operator std::string() const {
		JsonWriter j;
		j.begin();
		j.writeString("event", "error");
		j.writeString("message", message);
		j.writeInt("level", (int)level);
		if (!ticketRaw.empty()) {
			j.writeRaw("ticket", ticketRaw);
		}
		j.end();
		return j.str();
	}
};

enum class DebuggerParamType {
	REQUIRED,
	OPTIONAL,
	REQUIRED_LOOSE,
	OPTIONAL_LOOSE,
};

struct DebuggerRequest {
	DebuggerRequest(const char *n, net::WebSocketServer *w, const JsonGet &d, WebSocketClientInfo *client_info)
		: name(n), ws(w), data(d), client(client_info) {
	}

	const char *name;
	net::WebSocketServer *ws;
	const JsonGet data;
	WebSocketClientInfo *client;

	void Fail(const std::string &message) {
		ws->Send(DebuggerErrorEvent(message, LogLevel::LERROR, data));
		responseSent_ = true;
	}

	bool HasParam(const char *name, bool ignoreNull = false);
	bool ParamU32(const char *name, uint32_t *out, bool allowFloatBits = false, DebuggerParamType type = DebuggerParamType::REQUIRED);
	// For quantities that don't fit in 32 bits, like emulated microseconds - JSON numbers are
	// doubles anyway, which is exact well past any plausible session length.
	bool ParamF64(const char *name, double *out, DebuggerParamType type = DebuggerParamType::REQUIRED);
	bool ParamBool(const char *name, bool *out, DebuggerParamType type = DebuggerParamType::REQUIRED);
	bool ParamString(const char *name, std::string *out, DebuggerParamType type = DebuggerParamType::REQUIRED);

	JsonWriter &Respond();
	void Flush();
	bool Finish();

	// For a handler that answers later with a message carrying the request's ticket, rather than
	// a ticketless broadcast. The deferred event then tells the client to keep waiting for it.
	void ReplyLater() {
		replyLater_ = true;
	}
	bool RepliesLater() const {
		return replyLater_;
	}

private:
	JsonWriter writer_;
	bool responseBegun_ = false;
	bool responseSent_ = false;
	bool responsePartial_ = false;
	bool replyLater_ = false;
};

class DebuggerSubscriber {
public:
	virtual ~DebuggerSubscriber() {}

	// Subscribers can also broadcast if they have simple cases to.
	virtual void Broadcast(net::WebSocketServer *ws) {}
};

typedef std::function<void(DebuggerRequest &req)> DebuggerEventHandler;
typedef std::unordered_map<std::string_view, DebuggerEventHandler> DebuggerEventHandlerMap;

uint32_t RoundMemAddressUp(uint32_t addr);