-- Emerald Steps v1.0 --
-- written by ProjectRevoTPP --

-- KNOWN BUG: do not start the script during or before the copyright logo. The step counter changes during this when loading the variable from save block, so it would falsely increment steps by 1. --
-- recommended to start it after hitting new game or in the field doing tests. --

IWRAM = 0x03000000
EWRAM = 0x02000000

EMERALD_SAVEBLOCK_1_PTR = 0x3005D8C
EMERALD_STEPCOUNTER_OFFSET = 0x314C -- the counter is 8-bit, so we need to observe it changing and then keep a local step counter track.
EMERALD_CAN_PLAYER_MOVE = 0x3000F2C -- if 0, player can move, if 1, do not allow counter to increase.
EMERALD_RNG_COUNTER_ADDR = 0x020249C0

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

globaladdrchange = 0 -- used for pcall protect
is_vba = 0
true_step_counter = 0

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
	elseif is_vba == 1 then -- the reason we return 0 is because addresses are direct in VBA.
		return 0
	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))
		elseif is_vba == 1 then
			returnVar = memory.readbyte(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 16 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u16_le(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.readword(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 24 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u24_le(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.read_u24_le(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 32 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u32_le(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.readdword(addr)
		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))
		elseif is_vba == 1 then
			returnVar = memory.readbyte(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 16 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u16_be(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.readword(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 24 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u24_be(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.read_u24_be(addr)
		else
			print("Error changing memory domains.")
			return
		end
	elseif readtype == 32 then
		if pcall(trychangedomain) then
			returnVar = memory.read_u32_be(addr - getMemOffset(domaintype))
		elseif is_vba == 1 then
			returnVar = memory.readdword(addr)
		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(steps, rng_counter)
	gui.text(1,10,string.format("Current 8-bit Steps: %i",steps))
	if is_vba == 0 then
		gui.text(1,26,string.format("Current RNG Counter: %i",rng_counter))
	else
		gui.text(1,18,string.format("Current RNG Counter: %i",rng_counter))
	end
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
	  is_vba = 1
end

local save_ptr = readSpecific("IWRAM", 32, 0, EMERALD_SAVEBLOCK_1_PTR) -- load save ptr once
last_step_counter = readSpecific("EWRAM", 32, 0, save_ptr + EMERALD_STEPCOUNTER_OFFSET) -- set the last step counter.

repeat
	local save_ptr = readSpecific("IWRAM", 32, 0, EMERALD_SAVEBLOCK_1_PTR)
	local new_step_counter = readSpecific("EWRAM", 32, 0, save_ptr + EMERALD_STEPCOUNTER_OFFSET)
	local rng_counter = readSpecific("EWRAM", 32, 0, EMERALD_RNG_COUNTER_ADDR)
	drawguitext(new_step_counter, rng_counter)
	emu.frameadvance()
until false

gui.register(drawguitext)