--[[
	____    /        _____ ___ ____    /   
	|_ /   /| |  /  /  |   |_  |_ /   /| /|
	| \   /-| | /| /   |   |   | \   / |/ |
    |  \ /  | |/ |/    |   |__ |  \ /  /  |  (v.2026-01-23)

    lua traslation layer that uses 'stty' to get the terminal into raw mode.
	
	Reasorces:
		https://man7.org/linux/man-pages/man1/stty.1.html
		https://viewsourcecode.org/snaptoken/kilo/02.rawInputAndOutput.html
]]

local rawterm = {}
-- colors ======================================================================
local color = {}
local __color = {}
function __color:__tostring()
    return self.value
end
function __color:__concat(other)
    return tostring(self) .. tostring(other)
end
function __color:__call(s)
    return self .. s .. color.reset
end
__color.__metatable = {}

local function makecolor(value)
    return setmetatable(
        { value = string.char(27) .. '[' .. tostring(value) .. 'm' }, 
        __color
    )
end

local colors = {
    -- attributes	-- foreground	-- background
    reset = 0,		black = 30,		onblack = 40,
    clear = 0,		red = 31,		onred = 41,
    bright = 1,		green = 32,		ongreen = 42,
    dim = 2,		yellow = 33,	onyellow = 43,
    underscore = 4,	blue = 34,		onblue = 44,
    blink = 5,		magenta = 35,	onmagenta = 45,
    reverse = 7,	cyan = 36,		oncyan = 46,
    hidden = 8,		white = 37,		onwhite = 47,
}

for c, v in pairs(colors) do
    color[c] = makecolor(v)
end
rawterm.color = color

-- the terminal ================================================================
local savedTerminalState = ''
local function enterRawmode()
	os.execute('clear')
	io.write("\x1b[?25l") -- hide the cursor
	-- read the terminal settings with popen
	savedTerminalState = io.popen('stty -g'):read()
	-- use our sttings
	os.execute('stty -echo') -- DON'T: print keyboard input
	os.execute('stty -ignbrk') -- DON'T: ignore break characters
	os.execute('stty -brkint') -- DON'T: breaks cause an interrupt signal
	os.execute('stty -ignpar') -- DON'T: ignore characters with parity errors
	os.execute('stty -parmrk') -- DON'T: mark parity errors (with a 255-0-character sequence)
	os.execute('stty -inpck') -- DON'T: enable input parity checking
	os.execute('stty -istrip') -- DON'T: clear 8th bit
	os.execute('stty -inlcr') -- DON'T: translate newline to carriage return
	os.execute('stty -igncr') -- DON'T: ignore carriage return
	os.execute('stty -icrnl') -- DON'T: translate carriage return to newline
	os.execute('stty -ixon') -- DON'T: enable XON/XOFF flow control
	os.execute('stty -ixoff') -- DON'T: enable sending of start/stop characters
	os.execute('stty -icanon') -- DON'T: enable: erase, kill, werase, rprnt
	os.execute('stty -opost') -- DON'T: post prosess output
	os.execute('stty -isig') -- DON'T: enable interrupt, quit, and suspend special characters
	os.execute('stty -iuclc') -- DON'T: translate uppercase to lowercase.
	os.execute('stty -ixany') -- DON'T: let any character restart output, not only start character.
	os.execute('stty -imaxbel') -- DON'T: beep and do not flush a full input buffer on a character.
	os.execute('stty -xcase') -- DON'T: with icanon, escape with '\' for uppercase characters.
	os.execute('stty min 0') -- with -icanon, set N characters minimum for a completed read
	os.execute('stty time 0') -- with -icanon, set read timeout of N tenths of a second
	-- In theory we could just use os.execute('stty raw').
	-- But this way we get to see what 'stty raw' would be doing.
	-- Also need turn 'echo' off.
	-- And for some reason 'min' needed to be set to 0.
	-- Then we use os.execute('sleep '..sleepTime) to keep the program from..
	-- ..runing at max speed.
end
local function exitRawmode(reason)
	os.execute('clear')
	os.execute('stty '..savedTerminalState)
	io.write("\x1b[?25h") -- show the cursor
	io.write(color.reset..'')
	io.write('good bye :)\r\n')
	io.write(
		'-> '
		..color.black..color.ongreen..reason..color.clear
		..' <-\r\n'
	)
end
function rawterm.getSize()
	local values = {}
	local str = io.popen('stty size'):read()
	local start = 1
	while true do
		local find = str:find(' ',start)
		table.insert(values, str:sub(start, (find or #str+1)-1))
		if not find then break end
		start = find + 1
	end
	return unpack(values)
end

--[[
local og_error = error
function error(...)
	exitRawmode('ERROR:')
	og_error(...)
end
local og_assert = assert
function assert(shouldBeFine, notFine)
	if not shouldBeFine then
		exitRawmode('ASSERT:')
		og_assert(shouldBeFine, notFine)
	end
end
]]

local esc = string.char(27)
local translate = {
	[' '] = 'spacebar',
	[string.char(0)] = 'ctrl_spacebar',
	[string.char(1)] = 'ctrl_a',
	[string.char(2)] = 'ctrl_b',
	[string.char(3)] = 'ctrl_c',
	[string.char(4)] = 'ctrl_d',
	[string.char(5)] = 'ctrl_e',
	[string.char(6)] = 'ctrl_f',
	[string.char(7)] = 'ctrl_g',
	[string.char(8)] = 'ctrl_backspace', -- ctrl_h
	[string.char(9)] = 'tab', -- ctrl_i
	[string.char(10)] = 'ctrl_j',
	[string.char(11)] = 'ctrl_k',
	[string.char(12)] = 'ctrl_l',
	[string.char(13)] = 'return',
	[string.char(14)] = 'ctrl_n',
	[string.char(15)] = 'ctrl_o',
	[string.char(16)] = 'ctrl_p',
	[string.char(17)] = 'ctrl_q',
	[string.char(18)] = 'ctrl_r',
	[string.char(19)] = 'ctrl_s',
	[string.char(20)] = 'ctrl_t',
	[string.char(21)] = 'ctrl_u',
	[string.char(22)] = 'ctrl_v',
	[string.char(23)] = 'ctrl_w',
	[string.char(24)] = 'ctrl_x',
	[string.char(25)] = 'ctrl_y',
	[string.char(26)] = 'ctrl_z',
	[string.char(27)] = 'escape',
	[string.char(29)] = 'ctrl_]',
	[string.char(28)] = 'ctrl_\\',
	[string.char(31)] = 'ctrl_?',
	[string.char(32)] = 'spacebar',
	[string.char(127)] = 'backspace',
	[esc..'[A'] = 'up',
	[esc..'[B'] = 'down',
	[esc..'[D'] = 'left',	
	[esc..'[C'] = 'right',		
	[esc..'[1;2A'] = 'shift_up',
	[esc..'[1;2B'] = 'shift_down',
	[esc..'[1;2D'] = 'shift_left',	
	[esc..'[1;2C'] = 'shift_right',	
	[esc..'[1;3A'] = 'alt_up',
	[esc..'[1;3B'] = 'alt_down',
	[esc..'[1;3D'] = 'alt_left',	
	[esc..'[1;3C'] = 'alt_right',	
	[esc..'[1;4A'] = 'shift_alt_up',
	[esc..'[1;4B'] = 'shift_alt_down',
	[esc..'[1;4D'] = 'shift_alt_left',	
	[esc..'[1;4C'] = 'shift_alt_right',
	[esc..'[1;5A'] = 'ctrl_up',
	[esc..'[1;5B'] = 'ctrl_down',
	[esc..'[1;5D'] = 'ctrl_left',	
	[esc..'[1;5C'] = 'ctrl_right',
	[esc..'[1;6D'] = 'shift_ctrl_left',	
	[esc..'[1;6C'] = 'shift_ctrl_right',
	[esc..'[1;7D'] = 'ctrl_alt_left',	
	[esc..'[1;7C'] = 'ctrl_alt_right',
	[esc..'[1;7D'] = 'shift_ctrl_alt_left',	
	[esc..'[1;7C'] = 'shift_ctrl_alt_right',
	[esc..'[Z'] = 'shift_tab',
	[esc..'[5~'] = 'pageup',
	[esc..'[5;3~'] = 'alt_pageup',
	[esc..'[5;5~'] = 'ctrl_pageup',
	[esc..'[5;7~'] = 'ctrl_alt_pageup',
	[esc..'[6~'] = 'pagedown',
	[esc..'[6;3~'] = 'alt_pagedown',
	[esc..'[6;5~'] = 'ctrl_pagedown',
	[esc..'[6;7~'] = 'ctrl_alt_pagedown',
	[esc..'[3~'] = 'delete',
	[esc..'[3;3~'] = 'alt_delete',
	[esc..'[3;5~'] = 'ctrl_delete',
	[esc..'[3;7~'] = 'ctrl_alt_delete',
}
local letters = 'qwertyuiopasdfghjklzxcvbnm'
for i=1,#letters do
	local letter  = letters:sub(i, i)
	translate[esc..letter] = 'alt_'..letter
	translate[esc..letter:upper()] = 'alt_'..letter:upper()
end 

local buffer = ''
local function backupFunc(key, read)
	io.write(color.ongreen..color.black'rawterm (v2026-01-22)\r\n')
	io.write(color.green'Here you can see how keys are being translated.\r\n')
	io.write(color.green'Ctrl+Q to quit.\r\n')
	io.write(color.green'Ctrl+E to throw an error.\r\n')
	if key == 'ctrl_q' then
		return 'pressed ctrl_q' 
	end
	if key == 'ctrl_e' then
		error('error was thrown')
	end
	if #read > 1 and string.byte(read:sub(1,1)) == 27 then
		io.write(
			color.onred..color.black
			..'esacpe sequence:'..read:sub(2,#read)..'\n\r'
			..color.reset
		)
	end
	local value = ''
	if #key == 1 then
		value = color.onred..color.black..(string.byte(read) or 'no value?')
	end
	io.write(
		value
		..color.reset..':'
		..color.onblue..color.black..key..'\n\r'
		..color.reset
	)
	io.write()
	buffer = buffer..key
	buffer = buffer:gsub('\n','\n\r')
	io.write(buffer..'\n\r')
end

local function run(func, read)
	os.execute('clear')	
	local key = translate[read] or read or 'nil?'
	local status, rtn = pcall(func, key, read)
	if not status then 
		exitRawmode('ERROR in the function you gave:')
		error(rtn) 
	end
	if rtn then exitRawmode(rtn) end
	return rtn
end

rawterm.refreshrate = 1/100
function rawterm.run(func)
	func = func or backupFunc
	enterRawmode()
	if run(func, 'init') then return end
	while true do
		local read = io.read()
		if read then
			if run(func, read) then break end
		else
	  		os.execute("sleep "..rawterm.refreshrate)
		end
	end
end

return rawterm