-- The video rectangle:  the picture shifted, scaled and turned inside a Sinden border, with a
-- crosshair at a fixed overlay coordinate that must stay on the same point of the picture.  The
-- shift has no runtime setter, so it comes from --shiftx and --shifty and the script is run once
-- for each of the three shifts; the scale and the rotation step here.
dofile("Singe/Framework.singe")

local font          = fontLoad("Singe/FreeSansBold.ttf", 14)
local width, height = overlayGetWidth(), overlayGetHeight()
local crossX        = math.floor(width / 4)
local crossY        = math.floor(height / 4)
local frames        = 0
local shot          = 0
local steps         = {
	{ "as given", nil },
	{ "scale 50", function() return vldpSetScale(50) end },
	{ "scale 25", function() return vldpSetScale(25) end },
	{ "scale 100", function() return vldpSetScale(100) end },
	{ "rotate 90", function() return vldpSetRotate(90) end },
	{ "rotate 180", function() return vldpSetRotate(180) end },
	{ "rotate 270", function() return vldpSetRotate(270) end },
	{ "rotate 0", function() return vldpSetRotate(0) end },
}
local label   = steps[1][1]
local applied = true
local step    = 1

local STEP_FRAMES = 20
local SHOT_DELAY  = 10

fontSelect(font)
discPlay()

function onOverlayUpdate()
	frames = frames + 1
	overlayClear()

	-- A frame around the very edge of the picture, so the rectangle's position and size are visible.
	colorForeground(255, 255, 0)
	overlayBox(0, 0, width - 1, height - 1)
	overlayBox(3, 3, width - 4, height - 4)

	-- Corner ticks tell a turned picture from a shifted one:  the long arm is the top left corner.
	colorForeground(255, 0, 255)
	overlayLine(0, 0, 60, 0)
	overlayLine(0, 0, 0, 40)

	-- The crosshair sits a quarter of the way in and must stay on the same point of the picture.
	colorForeground(0, 255, 255)
	overlayCircle(crossX, crossY, 14)
	overlayLine(crossX - 24, crossY, crossX + 24, crossY)
	overlayLine(crossX, crossY - 24, crossX, crossY + 24)

	colorForeground(255, 255, 255)
	fontPrint(10, height - 46, string.format("%s  scale %d  rotate %d  applied %s", label, vldpGetScale(), vldpGetRotate(), tostring(applied)))
	fontPrint(10, height - 26, string.format("overlay %dx%d  crosshair %d,%d  disc frame %d", width, height, crossX, crossY, discGetFrame()))

	-- One step every STEP_FRAMES frames, shot SHOT_DELAY frames later so the change is on screen.
	if (frames % STEP_FRAMES) == 0 then
		step = (frames / STEP_FRAMES) + 1
		if steps[step] ~= nil then
			label = steps[step][1]
			if steps[step][2] ~= nil then
				applied = steps[step][2]()
			end
		end
	end
	if ((frames % STEP_FRAMES) == SHOT_DELAY) and (shot < #steps) then
		shot = shot + 1
		singeScreenshot()
	end
	if shot >= #steps and (frames % STEP_FRAMES) == SHOT_DELAY + 2 then
		singeQuit()
	end

	return OVERLAY_UPDATED
end