#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <time.h>

#include "GdbStub.h"
#include "Platform.h"

class Debug : public Gdb::StubCallbacks
{
public:
	Debug(){}
	~Debug(){}

	int GetCPU() const override { return 9; }

	u32 ReadReg(Gdb::Register reg) override
	{
		printf("[==>] read reg %d\n", (int)reg);
		if (reg == Gdb::Register::pc) return 0x000000df; // cpsr: irq,fiq disabled, arm, sys mode
		else return 0x69420;
	}
	void WriteReg(Gdb::Register reg, u32 value) override
	{
		printf("[==>] write reg %d: 0x%08x\n", (int)reg, value);
	}

	u32 ReadMem(u32 addr, int len) override
	{
		static const u32 words[] = {
			0xeafffffe,
			0xe0211002,
			0xe12fff1e,
			0
		};

		printf("[==>] read mem 0x%08x (size %u)\n", addr, len);

		// $: b $ (arm)
		return words[(addr>>2)&3] & ((1uLL<<len)-1);
	}
	void WriteMem(u32 addr, int len, u32 value) override
	{
		printf("[==>] write addr 0x%08x (size %u): 0x%08x\n", addr, len, value);
	}

	void ResetGdb() override
	{
		printf("[==>] RESET!!!\n");
	}
	int RemoteCmd(const u8* cmd, size_t len) override
	{
		printf("[==>] Rcmd: %s\n", cmd);
		return 0;
	}
};

int main(int argc, char** argv) {
	Debug debug;

	Gdb::GdbStub stub(&debug, (argc > 1) ? atoi(argv[1]) : 3333);
	if (!stub.Init()) return 1;

	do
	{
		while (true)
		{
			Gdb::StubState s = stub.Poll();

			if (s == Gdb::StubState::None || s == Gdb::StubState::NoConn)
			{
				struct timespec ts;
				ts.tv_sec = 0;
				ts.tv_nsec = 1000*1000; // 1 ms
				nanosleep(&ts, NULL);
				continue;
			}

			switch (s)
			{
			case Gdb::StubState::Attach:
				printf("[==>] attached\n");
				break;
			case Gdb::StubState::Break:
				printf("[==>] break execution\n");
				stub.SignalStatus(Gdb::TgtStatus::BreakReq, ~(u32)0);
				break;
			case Gdb::StubState::Continue:
				printf("[==>] continue execution\n");
				// TODO: send signal status on SIGSTOP? eh.
				break;
			case Gdb::StubState::Step:
				printf("[==>] single-step\n");
				stub.SignalStatus(Gdb::TgtStatus::SingleStep, ~(u32)0);
				break;
			case Gdb::StubState::Disconnect:
				printf("[==>] disconnect\n");
				stub.SignalStatus(Gdb::TgtStatus::None, ~(u32)0);
				break;
			}

			if (s == Gdb::StubState::Disconnect) break;
		}
	}
	while (false);

	stub.Close();
	return 0;
}

namespace Platform
{
void Log(LogLevel level, const char* fmt, ...)
{
    if (fmt == nullptr) return;

    va_list args;
    va_start(args, fmt);
    vprintf(fmt, args);
    va_end(args);
}
}