-- VT1200: how far does the boot get with the current (peripheral-less) driver,
-- and where does it end up spinning?  Samples the PC once per emulated frame and
-- prints a histogram of the hottest PCs at the end.
--
--   <mame> vt1200 -rompath harness/mame/roms -video none -sound none -nothrottle \
--       -debug -debugger none -debuglog \
--       -autoboot_script harness/mame/progress.lua -autoboot_delay 0
--
-- PROG_FRAMES overrides the frame budget (default 600).

local function hex(v) return string.format("%08X", v) end

local machine = manager.machine
local cpu = machine.devices[':maincpu']
local dbg = machine.debugger
local pc = cpu.state['PC']

if not dbg then
	print("ERROR: debugger not enabled; pass -debug")
	machine:exit()
	return
end

local maxframes = tonumber(os.getenv("PROG_FRAMES") or "600")
local frames = 0
local hist = {}
local first = {}

emu.register_frame_done(function()
	frames = frames + 1
	local v = pc.value
	hist[v] = (hist[v] or 0) + 1
	if not first[v] then first[v] = frames end
	if frames % 50 == 0 then
		print(string.format("frame %5d  PC=%s", frames, hex(v)))
	end
	if frames >= maxframes then
		print("--- distinct PCs sampled: " .. tostring((function()
			local n = 0
			for _ in pairs(hist) do n = n + 1 end
			return n
		end)()))
		print("--- hottest PCs (one sample per frame) ---")
		local list = {}
		for k, c in pairs(hist) do list[#list + 1] = {k, c} end
		table.sort(list, function(a, b) return a[2] > b[2] end)
		for i = 1, math.min(15, #list) do
			print(string.format("  PC=%s  samples=%d  first_frame=%d",
				hex(list[i][1]), list[i][2], first[list[i][1]]))
		end
		machine:exit()
	end
end, "vt1200-progress")

dbg.visible_cpu = cpu
dbg.execution_state = 'run'