-- "Basketweave" Tiling Graphics Element

local util    = require("scada-common.util")

local element = require("graphics.element")

---@class tiling_args
---@field fill_c cpair colors to fill with
---@field even? boolean whether to account for rectangular pixels
---@field border_c? color optional frame color
---@field parent graphics_element
---@field id? string element id
---@field x? integer 1 if omitted
---@field y? integer auto incremented if omitted
---@field width? integer parent width if omitted
---@field height? integer parent height if omitted
---@field gframe? graphics_frame frame instead of x/y/width/height
---@field fg_bg? cpair foreground/background colors
---@field hidden? boolean true to hide on initial draw

-- new tiling box
---@param args tiling_args
---@return graphics_element element, element_id id
local function tiling(args)
    element.assert(type(args.fill_c) == "table", "fill_c is a required field")

    -- create new graphics element base object
    local e = element.new(args)

    local fill_a = args.fill_c.blit_a
    local fill_b = args.fill_c.blit_b

    local even = args.even == true

    local start_x = 1
    local start_y = 1
    local inner_width = math.floor(e.frame.w / util.trinary(even, 2, 1))
    local inner_height = e.frame.h

    -- border
    if args.border_c ~= nil then
        start_x = 1 + util.trinary(even, 2, 1)
        start_y = 2

        inner_width = math.floor((e.frame.w - 2 * util.trinary(even, 2, 1)) / util.trinary(even, 2, 1))
        inner_height = e.frame.h - 2
    end

    -- check dimensions
    element.assert(inner_width > 0, "inner_width <= 0")
    element.assert(inner_height > 0, "inner_height <= 0")
    element.assert(start_x <= inner_width, "start_x > inner_width")
    element.assert(start_y <= inner_height, "start_y > inner_height")

    -- draw tiling box
    function e.redraw()
        local alternator = true

        if args.border_c ~= nil then
            e.w_set_bkg(args.border_c)
            e.window.clear()
        end

        -- draw pattern
        for y = start_y, inner_height + (start_y - 1) do
            e.w_set_cur(start_x, y)
            for _ = 1, inner_width do
                if alternator then
                    if even then
                        e.w_blit("  ", "00", fill_a .. fill_a)
                    else
                        e.w_blit(" ", "0", fill_a)
                    end
                else
                    if even then
                        e.w_blit("  ", "00", fill_b .. fill_b)
                    else
                        e.w_blit(" ", "0", fill_b)
                    end
                end

                alternator = not alternator
            end

            if inner_width % 2 == 0 then alternator = not alternator end
        end
    end

    -- initial draw
    e.redraw()

    return e.complete()
end

return tiling