-- emerald mudkip script v0.5 --
-- written by ProjectRevoTPP --

-- BIZHAWK ONLY FOR NOW --

IWRAM = 0x03000000
EWRAM = 0x02000000

RNG_ADDR = 0x3005D80
RNG_ADDR2 = 0x3005D84
RTC_ERROR_STATUS = 0x3000DB8 -- this needs to be
RNG_COUNTER = 0x020249C0

CORRECT_MUDKIP = 0x0E1AB5A1
CORRECT_MUDKIP_RNG_COUNTER = 1023 -- the function that actually creates the mudkip needs 1026, but the counter advances a few times before the correct function is called when this is 1026.

-- config --

force_mudkip = 1 -- 1 for true, 0 for false
display_gui = 0 -- 1 for true, 0 for false

------------------------

local last_known_rng = 0
local last_known_rng2 = 0
framecount = 0
rng_count = 0

globaladdrchange = 0 -- used for pcall protect

function trychangedomain()
	memory.usememorydomain(globaladdrchange)
end

-- this can probably be cleaned up but whatever.
function getMemOffset(domaintype)
	if domaintype == "IWRAM" then
		return IWRAM
	elseif domaintype == "EWRAM" then
		return EWRAM
	else
		print("Unsupported mem offset. Assuming main and returning 0.")
		return 0
	end
end

function readSpecific(domaintype, readtype, endian, addr) -- 0 endian for little, 1 for big
local returnVar = 0xFF
globaladdrchange = domaintype -- set the var for the pcall since pcall does not support passing arguments

if endian == 0 then
	if readtype == 8 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u8_le(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 16 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u16_le(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 24 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u24_le(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 32 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u32_le(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	else
		print("Invalid readtype. Exiting script.")
		return
	end
elseif endian == 1 then
	if readtype == 8 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u8_be(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 16 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u16_be(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 24 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u24_be(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 32 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u32_be(addr - getMemOffset(domaintype))
		else
			print("Error changing memory domains.")
			return
		end
	else
		print("Invalid readtype. Exiting script.")
		return
	end
else
	print("Invalid endian type. Exiting script.")
	return
end

return returnVar
end

function drawguitext(last_known_rng, rng_count, framecount)
	gui.text(1,10,string.format("Current RNG1: %08x",last_known_rng))
	gui.text(1,24,string.format("RNG Counter: %i",rng_count))
	gui.text(1,38,string.format("Frame Counter: %i",framecount))
end

function checkEmu()
		check = console.getavailabletools --this returns an error if not on Bizhawk
end

if pcall(checkEmu) then
      print("Loaded script on Bizhawk, setting memory domain to IWRAM")
	  memory.usememorydomain("IWRAM");
else
      print("VBA-RR or other emulator detected - will not switch memory domain.") -- dont do anything else, only bizhawk needs the memory domain set
end

if(readSpecific("IWRAM", 16, 0, RTC_ERROR_STATUS) == 0x0000) then
	memory.write_u16_le(RTC_ERROR_STATUS - getMemOffset("IWRAM"), 0x0FF0) -- force RTC to error.
	print("RTC forced into error state.")
end

local input = {}
input["A"] = true

-- force correct mudkip and advance --.
if force_mudkip == 1 then
	memory.write_u32_le(RNG_ADDR - getMemOffset("IWRAM"), CORRECT_MUDKIP) -- force RNG1
	--memory.write_u32_le() -- force RNG2 (unsure of correct behavior yet)
	memory.usememorydomain("EWRAM")
	memory.write_u32_le(RNG_COUNTER - getMemOffset("EWRAM"), CORRECT_MUDKIP_RNG_COUNTER) -- force RNG Counter
	memory.usememorydomain("IWRAM")
	-- press A. --
	joypad.set(input)
	-- advance frame and unpause.
	emu.frameadvance()
	print("Speedrun mudkip forced, proceeding")
end

repeat
if(readSpecific("IWRAM", 16, 0, RTC_ERROR_STATUS) == 0x0000) then
	memory.write_u16_le(RTC_ERROR_STATUS - getMemOffset("IWRAM"), 0x0FF0) -- force RTC to error.
	print("RTC forced into error state.")
end
last_known_rng = readSpecific("IWRAM", 32, 0, RNG_ADDR)
last_known_rng2 = readSpecific("IWRAM", 32, 0, RNG_ADDR2)
rng_count = readSpecific("EWRAM", 32, 0, RNG_COUNTER)
framecount = emu.framecount()
if display_gui == 1 then
	drawguitext(last_known_rng, rng_count, framecount)
end
emu.frameadvance()
until false

gui.register(drawguitext)