--[[
	LUA telemetry script for F5J training

	Displays the altitude at engine cut-off, 10s after that, and max reached during the flight
	Displays the remaining work time, remaining engine time and the flight time

	NB: You probably want your timer 1 set to Countdown: Voice with Minute Call
			       and timer 2 set to Countdown: Voice
	IMO, this works best if you have the 'Amber' sound packages (search RC Groups).

	If the engine is used more that 30s or twice in the same flight, the flight is declared invalid
	(a badflight.wav file can be used to signal this with audio; you have to provide this file yourself)

	Switch F is used to signal the end of the flight and stop the timers (up) then reset everything (down)

	Customization (look for these numbers in the code below):
	(1) CH1 is used for the throttle
	(2) The value where the throttle is meant to be active (defaults to -1024)
	(3) Switch F is used to end (up) then reset (down) the flight
	(4) Language for the sounds (for the texts, change the texts in the drawDashboard() and drawFault() functions)
	
	Releases
	1.00	Initial revision
	1.01	Updated the timer class - this corrects the voice countdown not restarting

	Mike, ON4MJ
--]]


-- Customization stuff

local THR = getFieldInfo( 'ch1' ).id 		-- (1) Change 'ch1' to your throttle output
local ALT = getFieldInfo( 'altitude' ).id
local SF = getFieldInfo( 'sf' ).id 		-- (3) Change 'sf' to another switch if you want (especially if you swapped it with SH)

local THROTTLE_MIN = -1020			-- (2) (normally -1024)

local SOUND_PATH = '/SOUNDS/EN/'		-- (4)



--
-- Timer wrapping
--
-- NB:
-- countdownBeep 	integer (none, beep, voice)
-- minuteBeep		bool
-- persistent		integer (none, flight, manual reset)
--
local function createTimer( timerId, startValue, countdownBeep, minuteBeep, persistent, startIt )
	-- Precondition: timerId is either 0 or 1
	local id = timerId
	local timer = model.getTimer( id )
	local target = 0


	local function getVal()
		timer.value = model.getTimer( id ).value
		return timer.value
	end

	local function setTarget( t )
		target = t
	end

	local function start()
		timer.mode = 1
		model.setTimer( id, timer )
	end

	local function stop()
		timer = model.getTimer( id )
		timer.mode = 0
		model.setTimer( id, timer )
		return timer.value
	end

	local function reset()
		timer.value = timer.start
		model.setTimer( id, timer )
		model.resetTimer( id )
	end


	local function drawImpl( x, y, val, att )
		lcd.drawTimer( x, y, val, att )
		return val
	end

	local function draw( x, y, att )
		return drawImpl( x, y, getVal(), att )
	end

	local function drawReverse( x, y, att )
		return drawImpl( x, y, target - getVal(), att )
	end


	-- "constructor"
	if countdownBeep ~= null then
		timer.countdownBeep = countdownBeep
	end

	if minuteBeep ~= null then
		timer.minuteBeep = minuteBeep
	end

	if persistent ~= null then
		timer.persistent = persistent
	end

	if startValue then
		timer.value = startValue
		timer.start = startValue
		target = startValue
	end

	timer.mode = startIt and 1 or 0
	model.setTimer( id, timer )


	return {
		start = start,
		stop = stop,
		reset = reset,
		draw = draw,
		drawReverse = drawReverse,
		getVal = getVal,
		setTarget = setTarget
	}
end


-- The F5J stuff

local alt = 0
local alt10 = 0
local max = 0
local state = 1 -- 1=reset; 2=launch; 3=cutoff; 4=glide; 5=landed; 6=disqualify


local timer1 = createTimer( 0, 600 )	-- flight time
local timer2 = createTimer( 1, 30 )	-- engine time
local time3 = 0

local THROTTLE_MIN_HYSTERESIS = THROTTLE_MIN + 4


local function vocalEnabled()
	return true
end

local function handleMax()
	local a = getValue( ALT )
	if a > max then
		max = a
	end
	return a
end

local function disqualify()
	if vocalEnabled() then
		playFile( SOUND_PATH .. 'badflight.wav' )
	end
	timer2.stop()
	timer1.stop()
	state = 6
end

local function checkThrottle()
	if getValue( THR ) > THROTTLE_MIN_HYSTERESIS then
		disqualify()
	end
end

local function checkReset()
	if getValue( SF ) < 0 then
		timer2.stop()
		timer1.stop()
		timer2.reset()
		timer1.reset()
		time3 = 0

		alt = 0
		alt10 = 0
		max = 0

		state = 1
		return true
	end
	return false
end

local function checkEnd()
	return (getValue( SF ) > 0)
end

local function goToLandedState()
	timer2.stop()
	timer1.stop()
	state = 5
end



-- state transition functions

local function resetState()
	-- wait for take-off
	if getValue( THR ) > THROTTLE_MIN_HYSTERESIS then
		timer2.start()
		timer1.start()
		state = 2
	end
end

local function launchState()
	-- wait for the motor cut
	if checkEnd() then
		goToLandedState()
	elseif getValue( THR ) <= THROTTLE_MIN then
		timer2.stop()
		alt = getValue( ALT )
		max = alt
		if vocalEnabled() then
			playNumber( alt, 6, 0 )
		end
		state = 3
	elseif timer2.getVal() < 0 then
		disqualify()
	end
end

local function cutoffState()
	local a = handleMax()

	if checkEnd() then
		goToLandedState()
	else
		-- wait for the 10s end
		if (time3 - (30 - timer2.getVal())) >= 10 then
				alt10 = a
				if vocalEnabled() then
					playNumber( alt10, 6, 0 )
				end
				state = 4
		else
			checkThrottle()
		end
	end
end

local function glideState()
	handleMax()

	-- wait for the end of flight
	if checkEnd() then
		goToLandedState()
	else
		checkThrottle()
	end
end

local function landedState()
	-- wait for reset
	checkReset()
end

local function disqualifyState()
	-- wait for end
	if checkEnd() then
		state = 5
	end
end




local functions = { resetState, launchState, cutoffState, glideState, landedState, disqualifyState }

function background()
	time3 = 600 - timer1.getVal()
	functions[ state ]()
end



local function drawDashboard()
	lcd.drawFilledRectangle( 0, 23, 212, 18, 0 )

	lcd.drawText( 4, 4, "Alt cut:", MIDSIZE )
	lcd.drawNumber( 64, 4, alt, MIDSIZE+LEFT )
	lcd.drawText( lcd.getLastPos(), 4, "m", 0 )

	lcd.drawText( 4, 26, "Alt 10s:", MIDSIZE+INVERS )
	lcd.drawNumber( 64, 26, alt10, MIDSIZE+LEFT+INVERS )
	lcd.drawText( lcd.getLastPos(), 26, "m", INVERS )
	
	lcd.drawText( 4, 48, "Alt max:", MIDSIZE )
	lcd.drawNumber( 64, 48, max, MIDSIZE+LEFT )
	lcd.drawText( lcd.getLastPos(), 48, "m", 0 )
	
	lcd.drawText( 120, 4, "Work:", MIDSIZE )
	timer1.draw( 174, 4, MIDSIZE )

	lcd.drawText( 120, 26, "Engine:", MIDSIZE+INVERS )
	timer2.draw( 174, 26, MIDSIZE+INVERS )

	lcd.drawText( 120, 48, "Flight:", MIDSIZE )
	lcd.drawTimer( 174, 48, time3, MIDSIZE )
end


local function drawFault()
	lcd.drawRectangle( 4, 4, 204, 56 )
	lcd.drawText( 40, 25, "INVALID FLIGHT", DBLSIZE+BLINK )
end


local function run()
	background()

	if state < 6 then
		drawDashboard()
	else
		drawFault()
	end
end

return {background=background, run=run}