m=peripheral.wrap("left")
p=peripheral.wrap("bottom")

term.redirect(m)

tX,tY=term.getSize()

local function writeTextCentered(text,y,tCol)
    if text==nil or y<=0 then return false; end
    sValue=(tX-string.len(text))/2;
    if tCol then term.setTextColor(tCol) end
    term.setCursorPos(sValue,y);
    term.write(text);
    term.setBackgroundColor(colors.green)
end

local function writeTextSpecificCentered(text,sX,eX,y,tCol)
    if text==nil or y<=0 then return false; end
    sValue=(((eX+1)-sX)-string.len(text))/2;
    if tCol then term.setTextColor(tCol) end
    term.setCursorPos(sValue+sX,y);
    term.write(text);
    term.setBackgroundColor(colors.green)
end

local function drawLoadingScreen(count,total,info)
    term.setBackgroundColor(colors.white)
    paintutils.drawLine(1,tY-3,tX,tY-3,colors.white)
    writeTextCentered(info,tY-3,colors.blue)
    paintutils.drawLine(2,tY-1,tX-2,tY-1,colors.white)
    paintutils.drawLine(2,tY-1,1+((count*(tX-2))/total),tY-1,colors.green)
end

function main()
    while true do
        h=p.getEnergyStored()
        mx=p.getMaxEnergyStored()
        if h==mx then
            rs.setOutput("back",true)
        else
            rs.setOutput("back",false)
        end
        pc=h/mx
        ts=tostring(tostring(h).."/"..tostring(mx).." ("..tostring(pc*100).."%)")
        paintutils.drawFilledBox(1,1,tX,tY,colors.white)
        paintutils.drawBox(1,tY-2,tX,tY,colors.lightGray)
        drawLoadingScreen(h,mx,ts)
        sleep(1)
    end
end

_,err=pcall(main)

term.setBackgroundColor(colours.black)
term.setTextColor(colours.white)

print("\n\n\n\n"..err)