-- Lesson 20:  Menus And Screens.  The finished script, exactly as the lesson ends.
dofile("Singe/Framework.singe")

overlaySetResolution(discGetWidth(), discGetHeight())
singeSetPauseKeyEnabled(false)

local SHIP_Y = 300

local ship    = spriteLoad(DIR .. "art/spaceship.png")
local hudFont = fontLoad("Singe/FreeSansBold.ttf", 20)
local shipX   = 0
local speed   = 2
local score   = 0
local paused  = false
local gui     = nil
local page    = nil


local function say(text)
    if gui ~= nil then
        guiSetValue(gui, page, "status", text)
    end
end


local function closeMenu()
    paused = false
    singeSetPauseFlag(false)
    if gui ~= nil then
        guiHide(gui, page)
        guiSetInput(gui, false)
    end
end


local function openMenu()
    paused = true
    singeSetPauseFlag(true)
    if gui ~= nil then
        guiSetValue(gui, page, "score", string.format("%06d", score))
        guiShow(gui, page)
        guiSetInput(gui, true)
    end
end


if singeHasGpu() then
    gui  = guiNew(overlayGetWidth(), overlayGetHeight())
    page = guiLoad(gui, DIR .. "pause.rml")
    guiHide(gui, page)
    guiSetInput(gui, false)

    guiSetHandler(gui, page, "resume", "click", function()
        closeMenu()
    end)

    guiSetHandler(gui, page, "restart", "click", function()
        score = 0
        shipX = 0
        closeMenu()
    end)

    guiSetHandler(gui, page, "quit", "click", function()
        singeQuit()
    end)

    guiSetHandler(gui, page, "speed", "change", function(g, d, id, event, value)
        speed = math.floor(tonumber(value))
        say("Speed " .. speed)
    end)
end


function onInputPressed(what)
    if what == SWITCH_PAUSE then
        if paused then
            closeMenu()
        else
            openMenu()
        end
    end
end


function onOverlayUpdate()
    overlayClear()

    if not paused then
        shipX = shipX + speed
        if shipX > overlayGetWidth() then
            shipX = -spriteGetWidth(ship)
            score = score + 10
        end
    end
    spriteDraw(ship, shipX, SHIP_Y)

    fontSelect(hudFont)
    colorForeground(255, 255, 255)
    fontPrint(16, 16, string.format("SCORE %06d", score))
    fontPrint(16, 40, "P pauses")

    if paused then
        if gui ~= nil then
            guiDraw(gui)
        else
            colorForeground(255, 211, 90)
            fontPrint(16, 70, "PAUSED -- no GPU, so no menu")
        end
    end

    return OVERLAY_UPDATED
end


function onShutdown()
    if gui ~= nil then
        guiDelete(gui)
    end
    spriteUnload(ship)
    fontUnload(hudFont)
end