local gc=love.graphics
local rnd=math.random
local int,ceil=math.floor,math.ceil
local char=string.char

local function b2(i)
    if i==0 then return 0 end
    local s=""
    while i>0 do
        s=(i%2)..s
        i=int(i/2)
    end
    return s
end
local function b8(i)
    if i==0 then return 0 end
    local s=""
    while i>0 do
        s=(i%8)..s
        i=int(i/8)
    end
    return s
end
local function b16(i)
    if i==0 then return 0 end
    local s=""
    while i>0 do
        s=char((i%16<10 and 48 or 55)+i%16)..s
        i=int(i/16)
    end
    return s
end

local levels={
    function()-- <+> [,10]
        local s=rnd(2,9)
        local a=rnd(1,s)
        return a.."+"..s-a,s
    end,nil,nil,
    function()-- <+> [,20]
        local s=rnd(10,18)
        local a=rnd(s-9,int(s/2))
        return a.."+"..s-a,s
    end,nil,nil,
    function()-- <+> [,100]
        local s=rnd(22,99)
        local a=rnd(11,int(s/2))
        return a.."+"..s-a,s
    end,nil,nil,
    function()-- <-> [,10]
        local s=rnd(2,9)
        local a=rnd(1,s)
        return s.."-"..a,s-a
    end,nil,nil,
    function()-- <-> [,100]
        local s=rnd(22,99)
        local a=rnd(11,int(s/2))
        return s.."-"..a,s-a
    end,nil,nil,
    function()-- <-> [-10,]
        local s=rnd(-8,-1)
        local a=rnd(1,8)
        return a.."-"..a-s,s
    end,nil,nil,nil,nil,
    function()-- <*> [,100]
        local b=rnd(21,89)
        local a=rnd(ceil(b/10),9)
        b=int(b/a)
        return a.."*"..b,a*b
    end,nil,nil,nil,nil,
    function()-- <*> [,1000]
        local a,b=rnd(4,8),rnd(42,96)
        return a.."*"..b,a*b
    end,nil,nil,
    function()-- </> [,100]
        local b=rnd(21,89)
        local a=rnd(ceil(b/10),9)
        b=int(b/a)
        return a*b.."/"..a,b
    end,nil,nil,nil,nil,
    function()-- <%3>
        local s=rnd(5,17)
        return s.."%3",s%3
    end,nil,nil,
    function()-- <%> [,10]
        local s=rnd(21,62)
        local a=rnd(3,9)
        return s.."%"..a,s%a
    end,nil,nil,nil,nil,
    function()-- <b> [,10]
        local a=rnd(2,9)
        return{COLOR.N,b2(a)},a
    end,nil,nil,nil,nil,
    function()-- <o>
        local a=rnd(9,63)
        return{COLOR.lR,b8(a)},a
    end,nil,nil,nil,
    function()-- <h>
        local a=rnd(17,255)
        return{COLOR.J,b16(a)},a
    end,nil,nil,
    function()-- <b+>
        local s=rnd(9,31)
        local a=rnd(5,int(s/2))
        return{COLOR.N,b2(a),COLOR.Z,"+",COLOR.N,b2(s-a)},s
    end,nil,nil,nil,nil,
    function()-- <o+>
        local s=rnd(18,63)
        local a=rnd(9,int(s/2))
        return{COLOR.lR,b8(a),COLOR.Z,"+",COLOR.lR,b8(s-a)},s
    end,nil,nil,nil,
    function()-- <h+>
        local s=rnd(34,255)
        local a=rnd(17,int(s/2))
        return{COLOR.J,b16(a),COLOR.Z,"+",COLOR.J,b16(s-a)},s
    end,nil,nil,
    function()return "Coming S∞n"..(rnd()<.5 and""or" "),1e99 end,
}setmetatable(levels,{__index=function(self,k)return self[k-1]end})

local level

local input,inputTime=0,0
local question,answer
local function newQuestion(lv)
    return levels[lv]()
end

local function check(val)
    if val==answer then
        level=level+1
        input=""
        inputTime=0
        local newQ
        repeat
            newQ,answer=newQuestion(level)
        until newQ~=question
        question=newQ
        SFX.play('reach')
    end
end

local scene={}

function scene.sceneInit()
    input=""
    inputTime=0
    level=1
    question,answer=newQuestion(1)
    BGM.play('truth')
end

function scene.keyDown(key,isRep)
    if isRep then return end
    if key:sub(1,2)=="kp"then key=key:sub(3)end
    if #key==1 and("0123456789"):find(key,nil,true)then
        if #input<8 then
            input=input..key
            inputTime=1
            check(tonumber(input))
            SFX.play('touch')
        end
    elseif key=="-"then
        if #input<8 then
            if input:find("-")then
                input=input:sub(2)
            else
                input="-"..input
            end
            inputTime=1
            check(tonumber(input))
            SFX.play('hold')
        end
    elseif key=="backspace"then
        input=""
        inputTime=0
    elseif key=="s"then
        check(answer)
    elseif key=="escape"then
        SCN.back()
    end
end

function scene.update(dt)
    if inputTime>0 then
        inputTime=inputTime-dt
        if inputTime<=0 then
            input=""
        end
    end
end
function scene.draw()
    FONT.set(35)
    gc.setColor(COLOR.Z)
    GC.mStr("["..level.."]",640,30)

    FONT.set(100)
    if type(question)=='table'then gc.setColor(1,1,1)end
    GC.mStr(question,640,60)

    FONT.set(80)
    gc.setColor(1,1,1,inputTime)
    GC.mStr(input,640,160)
end

scene.widgetList={
    WIDGET.newKey{name='X',x=540,y=620,w=90,font=60,fText="X",code=pressKey"backspace"},
    WIDGET.newKey{name='0',x=640,y=620,w=90,font=60,fText="0",code=pressKey"0"},
    WIDGET.newKey{name='-',x=740,y=620,w=90,font=60,fText="-",code=pressKey"-"},
    WIDGET.newKey{name='1',x=540,y=520,w=90,font=60,fText="1",code=pressKey"1"},
    WIDGET.newKey{name='2',x=640,y=520,w=90,font=60,fText="2",code=pressKey"2"},
    WIDGET.newKey{name='3',x=740,y=520,w=90,font=60,fText="3",code=pressKey"3"},
    WIDGET.newKey{name='4',x=540,y=420,w=90,font=60,fText="4",code=pressKey"4"},
    WIDGET.newKey{name='5',x=640,y=420,w=90,font=60,fText="5",code=pressKey"5"},
    WIDGET.newKey{name='6',x=740,y=420,w=90,font=60,fText="6",code=pressKey"6"},
    WIDGET.newKey{name='7',x=540,y=320,w=90,font=60,fText="7",code=pressKey"7"},
    WIDGET.newKey{name='8',x=640,y=320,w=90,font=60,fText="8",code=pressKey"8"},
    WIDGET.newKey{name='9',x=740,y=320,w=90,font=60,fText="9",code=pressKey"9"},
    WIDGET.newButton{name='back',x=1200,y=660,w=110,h=60,font=60,fText=CHAR.icon.back,code=pressKey"escape"},
}

return scene