local gfx = love.graphics
---
---@generic T
---@param shape T | fun()
---@param process fun(entity: T, dt: number, system: System) | nil
---@return System | { entities: T[] }
local function drawSystem(name, shape, process)
    local system = filteredSystem(name, shape, process, function(_, a, b)
        if a.z ~= nil and b.z ~= nil then
            return a.z < b.z
        end
        if a.z ~= nil then
            return true
        end
        return false
    end)
    system.isDrawSystem = true
    return system
end

filteredSystem("mapGridPositionToRealPosition", { gridPosition = T.XyPair }, function(e, dt, system)
    local target = PositionAtGridXy(e.gridPosition.x, e.gridPosition.y)
    if e.position == nil then
        e.position = target
        return
    end
    local speed = 100
    if e.ballEffects and e.ballEffects.movement then
        local movement = e.ballEffects.movement
        local longTarget = PositionAtGridXy(e.gridPosition.x + movement.x, e.gridPosition.y + movement.y)
        local xDiff = e.position.x - longTarget.x
        local yDiff = e.position.y - longTarget.y
        speed = 30 + math.sqrt((xDiff * xDiff) + (yDiff * yDiff))
    end
    local stops = 0

    local xDiff = target.x - e.position.x
    local xChange = dt * speed * math.sign(xDiff)
    if math.abs(xDiff) <= math.abs(xChange) then
        e.position.x = target.x
        stops = stops + 1
    else
        e.position.x = e.position.x + xChange
    end

    local yDiff = target.y - e.position.y
    local yChange = dt * speed * math.sign(yDiff)
    if math.abs(yDiff) <= math.abs(yChange) then
        e.position.y = target.y
        stops = stops + 1
    else
        e.position.y = e.position.y + yChange
    end

    if e.endAnimating and stops == 2 then
        RoundSystem:remove("animating")
    end
    system.world:addEntity(e)
end)

local spriteDrawSystem = drawSystem(
    "drawSprites",
    { position = T.XyPair, drawAsSprite = T.Drawable, rotation = Maybe(T.number) },
    function(e)
        if not e.drawAsSprite then
            return
        end
        gfx.draw(e.drawAsSprite, e.position.x, e.position.y)
    end
)

function spriteDrawSystem:preProcess()
    gfx.setColor(1, 1, 1)
end

local margin = 8

drawSystem(
    "drawText",
    { position = T.XyPair, drawAsText = { text = T.str, style = Maybe(T.str), font = Maybe(T.pd_font) } },
    function(e)
        local font = e.drawAsText.font or gfx.getFont() -- e.drawAsText.font or AshevilleSans14Bold
        local textHeight = font:getHeight()
        local textWidth = font:getWidth(e.drawAsText.text)

        local bgLeftEdge = e.position.x - margin -- - (textWidth / 2)
        local bgTopEdge = e.position.y - 2
        local bgWidth, bgHeight = textWidth + (margin * 2), textHeight + 2

        if e.drawAsText.style == TextStyle.Inverted then
            gfx.setColor(0, 0, 0)
            gfx.rectangle("fill", bgLeftEdge, bgTopEdge, textWidth + margin, textHeight + 2)
            gfx.setColor(1, 1, 1)
        elseif e.drawAsText.style == TextStyle.Bordered then
            gfx.setColor(1, 1, 1)
            gfx.rectangle("fill", bgLeftEdge, bgTopEdge, bgWidth, bgHeight)

            gfx.setColor(0, 0, 0)
            gfx.rectangle("line", bgLeftEdge, bgTopEdge, bgWidth, bgHeight)
        end

        gfx.print(e.drawAsText.text, bgLeftEdge + margin, bgTopEdge + margin)
    end
)

drawSystem("drawRectangles", { position = T.XyPair, drawAsRectangle = { size = T.XyPair } }, function(e, _, _)
    gfx.setColor(1, 1, 1, 0.5)
    local mode = e.drawAsRectangle.mode or "line" -- (e.highlighted and "fill" or "line")
    gfx.rectangle(mode, e.position.x, e.position.y, e.drawAsRectangle.size.x, e.drawAsRectangle.size.y)
end)