local module = {}
setmetatable(module, {__index=_G})
setfenv(1, module)


local m = require 'marigold-svg.marigold'


function capitalize(str)
	return string.gsub(str, "^.", string.upper)
end


--===== misc =====--

local function stack(...)
	local array = {...}
	local l
	l = function(acc_f, acc_h)
		if #array == 0 then return acc_f, acc_h end
		local f, h = array[1][1], array[1][2]
		table.remove(array, 1)
		local acc_f = function(y)
			local tbl = acc_f(y)
			table.insert(tbl, f(y+acc_h))
			return tbl
		end
		local acc_h = acc_h + h
		return l(acc_f, acc_h)
	end
	local f, h = l(function(y) return {} end, 0)
	return function(y) return m.g(f(y)) end, h
end

local function pad(top, bottom, f, h)
	return function(y) return f(y+top) end, top + h + bottom
end


local function _divider()
	local size = 3
	return function(y) return m.rect{
		x=0, y=y, width=500, height=size,
		style="fill:darkred;",
	} end, size
end
local divider = function() return pad(0, 10, _divider()) end


--===== basic stats =====--

local function name(stats)
	local size = 40
	return function(y)
		return m.text(stats.name, {
			x=10, y=y+size,
			style="font-size:"..size.."px;font-variant-caps:small-caps;stroke:black;fill:darkred;font-family:serif",
		})
	end, size
end
local function subheading(stats)
	local size = 14
	return function(y)
		return m.text(
			string.format("%s %s, %s", capitalize(stats.size), stats.type, stats.alignment),
			{
				x=10, y=y+size, style="font-size:"..size.."px;font-style:italic;"
			}
		)
	end, size
end

local function header(stats)
	local f, h = stack(
		{pad(10, 10, name(stats))},
		{pad(0, 10, subheading(stats))}
	)
	return f, h
end

local function _statline(name, value)
	local size = 14
	return function(y) return m.text(
		'<tspan style="font-weight:bold">'..name..'</tspan> '..value,
		{ x=10, y=y+size, style="font-size:"..size.."px;fill:darkred;" }
	) end, 14
end
local statline = function(name, value) return pad(0, 2, _statline(name, value)) end

local function armor_hp(stats)
	local f, h = pad(0, 10, stack(
		{statline('Armor Class', stats.ac)},
		{statline('Hit Points', stats.hp)},
		{statline('Speed', stats.speed)}
	))
	return f, h
end

local function bonus(ability_score)
	return math.floor( (ability_score-10)/2 )
end
local function scorebox(name, ability_score, x, y)
	local score = tonumber(ability_score)
	local value = string.format("%d (%s%d)", score, (score<0 and '-') or '+', bonus(score))
	return m.g{
		m.text(name, { x=x+10, y=y+15, style="font-weight:bold;font-size:15px;fill:darkred" }),
		m.text(value, {x=x, y=y+30, style="font-size:15px;fill:darkred;" }),
	}
end
local function ability_scores(stats)
	return function(y) return m.g{
		scorebox('STR', stats.str, 10, y),
		scorebox('DEX', stats.dex, 90, y),
		scorebox('CON', stats.con, 170, y),
		scorebox('INT', stats.int, 250, y),
		scorebox('WIS', stats.wis, 330, y),
		scorebox('CHA', stats.cha, 410, y),
	} end, 40
end

local function base(stats)
	local f, h = stack(
		{header(stats)},
		{divider()},
		{armor_hp(stats)},
		{divider()},
		{ability_scores(stats)},
		{divider()}
	)
	return f, h
end


--===== attributes =====--

local function attribs(stats)
	return function(y) return m.rect{
		x=0, y=y, width=500, height=20,
		style="fill:blue",
	} end, 20
end


--===== actions =====-- 

local function actions(stats)
	return function(y) return m.g{} end, 0
end


--===== draw =====--

function draw(stats)
	local f, h = stack({base(stats)}, {attribs(stats)}, {actions(stats)})
	return m.render(m.svg{
		viewBox = string.format("0 0 500 %d", h),
		width = 500,
		height = height,
		style = "font-family:sans-serif;",
		f(0),
	})
end


return module