local p = {}

local compress_sparse_array = require('Module:TableTools').compressSparseArray



local function arg_or_default(arg, default)

	if arg and mw.text.trim(arg) ~= '' then

		return arg

	else

		return default

	end

end



local incoming_args = {

	'other-color' = 'other_color_default()',

	style = nil,

	thumb = nil,

	labeln = nil,

	valuen = nil,

	colorn = 'get_graph_color(n)',

	caption = nil,

	other = nil,

	footer = nil

}



local graph_colors = {

	'#1F78B4',

	'#33A02C',

	'#FF7F00',

	'#6A3D9A',

	'#B15928',

	'#A6CEE3',

	'#B2DF8A',

	'#FB9A99',

	'#FDBF6F',

	'#CAB2D6',

	'#FFFF99',

	'#FEEBE2',

	'#A9A9A9'

}

	

local function get_graph_color(nth_item)

	return graph_colorsmath.max(math.min(nth_item, #graph_colors), 1)]

end



local function get_css_for_slices(args)

	local slices = {}

	local degree_ratio = 360/100



	for k, v in pairs(args) do

		if k:match('value%d+') then

			local number = k:find('(%d+)')

			slicesnumber = { value = tonumber(v) * degree_ratio }

		end

	end

	

	-- second loop because we need to guarantee that we've found all the potential slices

	-- before attempting to add their labels and colors

	for k, v in pairs(args) do

		if k:match('label%d+') then

			local number = k:find('(%d)')

			if slicesnumber then -- if we don't have a value, then no label set

				slicesnumber]['label' = v

			end

		end

		if k:match('color%d+') then

			local number = k:find('(%d)')

			if slicesnumber then -- if we don't have a value, then no color set

				slicesnumber]['color' = v

			end

		end

	end

	

	compress_sparse_array(slices)

	local conical_css_for_slices = {}

	local accumulated_value = 0

	

	for i, slice in ipairs(slices) do

		local value = slice.value

		local color = slice.color or get_graph_color(i)

		local next_accumulated_value = accumulated_value + value

		

		if i == 1 then

			-- we only need the end degree for the first

			table.insert(conical_css_for_slices, color .. ' ' .. value .. 'deg,')

		elseif i > 1 and i < #slices then

			-- need both start and end for the first, start is the previous end

			table.insert(conical_css_for_slices, color .. ' ' .. accumulated_value .. 'deg ' .. next_accumulated_value .. 'deg,')

		elseif i == #slices then

			-- we only need the start degree for the last

			table.insert(conical_css_for_slices, color .. ' ' .. accumulated_value .. 'deg')

		end

		

		accumulated_value = next_accumulated_value

	end

	return 'background: conic-gradient(' .. table.concat(conical_css_for_slices) .. ')'

end



function p._main(args)

	

	local root = mw.html.create('div')

	root:addClass('pie-chart thumb')

		:cssText(arg_or_default(args.style, nil))

	

	local thumb = arg_or_default(args.thumb, nil)

	local thumb_class = 'tright'

	if thumb and (thumb == 'center' or thumb == 'none') then

		thumb_class = 'tnone'

	elseif thumb and thumb == 'left' then

		thumb_class = 'tleft'

	end

	root:addClass(thumb_class)

	

	local radius = tonumber(arg_or_default(args.radius, 100))

	local diameter = radius * 2

	root:tag('div')

		:addClass('pie-chart-inner thumbinner')

		:css('width', (diameter + 2) .. 'px')

	

	local chart = mw.html.create('div')

	chart:addClass('pie-chart-chart mw-no-invert')

	chart:css('border-radius', '50%') -- can be in pie chart/styles.css if we have one

	chart:css('width', diameter .. 'px')

	chart:css('height', diameter .. 'px')

	

	local conic_css = get_css_for_slices(args)

	chart:cssText(conic_css)



	if thumb and thumb == 'center' then

		local root_container = mw.html.create('div')

		root_container:addClass('pie-chart-container center')

			:node(root)

		return root_container

	end



	return root

	

end



function p.main(frame)

	return p._main(frame:getParent().args)

end



return p