Module:Sandbox/Erutuon/Temperature arrays

f = {}
degree = "°" -- used by add_unit_names()
minus = "−" -- used by makeRow() and makeTable()
thinSpace = mw.ustring.char(0x2009) -- used by makeCell()

-- Error message handling
message = ""

local function add_message(new_message)
	if show then
		if check_for_string(message) then
			message = message .. " " .. new_message
		else
			message = "Notices: " .. new_message
		end
	end
end

-- Input and output parameters
local function get_format (frame)
	local input_parameter = frame.args.input
	local output_parameter = frame.args.output
	
	if input_parameter == nil then
		error("Please provide the number of values and a unit in the input parameter")
	else
		length = tonumber(string.match(input_parameter, "(%d+)")) -- Find digits in the input parameter.
		input_unit = string.match(input_parameter, "([CF])") -- C or F
		if string.find(input_parameter, "[^CF%d%s]") then
			add_message("There are extraneous characters in the <span style=\"background-color: #EEE; font-family: monospace;\">output</span> parameter.")
		end
	end
	
	if input_unit == "C" then
		output_unit = "F"
	elseif input_unit == "F" then
		output_unit = "C"
	else
		error ("Please provide an input unit in the input parameter: F for Fahrenheit or C for Celsius", 0)
	end
	
	if length == nil then
		error ("get_format has not found a length value in the input parameter")
	end
	
	if output_parameter == nil then
		add_message("No output format has been provided in the <span style=\"background-color: #EEE; font-family: monospace;\">output</span> parameter.")
	else
		cell_format = {}
		local n = 1
		for unit in output_parameter:gmatch("[CF]") do
			cell_format[n] = unit
			n = n + 1
			if n > 2 then
				break
			end
		end
		local function set_format(key, formatVariable, formatValue1, formatValue2)
			if string.find(output_parameter, key) then
				cell_format[formatVariable] = formatValue1
			else
				cell_format[formatVariable] = formatValue2
			end
		end
		if cell_format[1] then
			cell_format.first = cell_format[1]
		else
			error("C or F not found in output parameter")
		end
		if cell_format[2] == nil then
			cell_format["convert_units"] = "no"
		else
			if cell_format[2] == cell_format[1] then
				error("There should not be two of the same unit name in the output parameter.")
			else
				cell_format["convert_units"] = "yes"
			end
		end
		set_format("unit", "unit_names", "yes", "no")
		set_format("no ?color", "color", "no", "yes")
		set_format("sort", "sortable", "yes", "no")
		set_format("full ?size", "small_font", "no", "yes")
		set_format("no ?brackets", "brackets", "no", "yes")
		set_format("round", "decimals", "0", "")
		if string.find(output_parameter, "line break") then
			cell_format["line_break"] = "yes"
		elseif string.find(output_parameter, "one line") then
			cell_format["line_break"] = "no"
		else
			cell_format["line_break"] = "auto"
		end
		if string.find(output_parameter, "one line") and string.find(output_parameter, "line break") then
			error("Place either \"one line\" or \"line break\" in the output parameter, not both")
		end
	end
	if frame.args.palette == nil then
		palette = "cool2avg"
	else
		palette = frame.args.palette
	end
	
	if frame.args.messages == "show" then
		show = true
	else
		show = false
	end
	
	return length, input_unit, output_unit
end

-- Number and string-handling functions
local function check_for_number(value)
	return type(tonumber(value)) == "number"
end

function check_for_string(string)
	string = tostring(string)
	return string ~= "" and string ~= nil
end

local function round(value, decimals)
	value = tonumber(value)
	if type(value) == "number" then
		local string = string.format("%." .. decimals .. "f", value)
		return string
	elseif value == nil then
		value = "nil"
		add_message("Format was asked to operate on " .. value .. ", which cannot be converted to a number.", 2)
		return ""
	end
end

local function convert(value, decimals, unit) -- Unit is the unit being converted from. It defaults to input_unit.
	if not unit then
		unit = input_unit
	end
	if check_for_number(value) then
		local value = tonumber(value)
		if unit == "C" then
			add_message(value .. " " .. degree .. unit .. " was converted.")
			return round(value * 9/5 + 32, decimals)
		elseif unit == "F" then
			add_message(value .. " " .. degree .. unit .. " was converted.")
			return round((value - 32) * 5/9, decimals)
		else
			error("Input unit not recognized", 2)
		end
	else
		return "" -- Setting result to empty string if value is not a number avoids concatenation errors.
	end
end

-- Input parsing
function make_array(parameter, array, frame)
	local array = {}
	local n = 1
	for number in parameter:gmatch("%-?%d+%.?%d?") do
		local number = number
		if n == 1 then
			local decimals = number:match("%.(%d+)")
			if decimals == nil then
				precision = "0"
			else
				precision = #decimals
			end
		end
		table.insert(array, n, number)
		n = n + 1
		if n > length then
			break
		end
	end
	if not array[length] then
		add_message("There are not " .. length .. " values in the " .. parameter .. " parameter.")
	end
	return array, precision
end

function make_arrays(frame)
	get_format(frame)
	local parameter_a = frame.args.a
	local parameter_b = frame.args.b
	local parameter_c = frame.args.c
	if parameter_a then
		a = make_array(parameter_a, a, frame)
	else
		error("Please provide a set of numbers in parameter a")
	end
	if parameter_b then
		b = make_array(parameter_b, b, frame)
	else
		add_message("There is no content in parameter <span style=\"background-color: #EEE; font-family: monospace;\">b</span>.")
	end
	if parameter_c then
		c = make_array(parameter_c, c, frame)
	else
		add_message("There is no content in parameter <span style=\"background-color: #EEE; font-family: monospace;\">c</span>.")
	end
	return a, b, c
end

-- Color generation

palettes = {
	-- The first three arrays in each palette defines background color using a table of four numbers,
	-- say { 11, 22, 33, 44 } (values in °C).
	-- That means the color is 0 below 11 and above 44, and is 255 from 22 to 33.
	-- The color rises from 0 to 255 between 11 and 22, and falls between 33 and 44.
	cool = {
		{ -42.75,   4.47, 41.5, 60   },
		{ -42.75,   4.47,  4.5, 41.5 },
		{ -90   , -42.78,  4.5, 23   },
		white = { -23.3, 37.8 },
	},
	cool2 = {
		{ -42.75,   4.5 , 41.5, 56   },
		{ -42.75,   4.5 ,  4.5, 41.5 },
		{ -90   , -42.78,  4.5, 23   },
		white = { -23.3, 35 },
	},
	cool2avg = {
		{ -38,   4.5, 25  , 45   },
		{ -38,   4.5,  4.5, 30   },
		{ -70, -38  ,  4.5, 23   },
		white = { -23.3, 25 },
	},
}

local function temperature_color(palette, value, out_rgb)
	--[[ Return style for a table cell based on the given value which
		should be a temperature in °C. ]]
	local background_color, text_color
	value = tonumber(value)
	if value == nil then
		background_color, text_color = 'FFF', '000'
		add_message("Value supplied to <span style=\"background-color: #EEE; font-family: monospace;\">temperature_color</span> is not recognized.")
	else
		local min, max = unpack(palette.white or { -23, 35 })
		if value < min or value >= max then
			text_color = 'FFF'
		else
			text_color = '' -- This assumes that black text color is the default for most readers.
		end

		local background_rgb = out_rgb or {}
		for i, v in ipairs(palette) do
			local a, b, c, d = unpack(v)
			if value <= a then
				background_rgb[i] = 0
			elseif value < b then
				background_rgb[i] = (value - a) * 255 / (b - a)
			elseif value <= c then
				background_rgb[i] = 255
			elseif value < d then
				background_rgb[i] = 255 - ( (value - c) * 255 / (d - c) )
			else
				background_rgb[i] = 0
			end
		end
		background_color = string.format('%02X%02X%02X', background_rgb[1], background_rgb[2], background_rgb[3])
	end
	if text_color == "" then
		return background_color
	else
		return background_color, text_color
	end
end

local function color_CSS(background_color, text_color)
	if background_color and text_color then
		return 'background: #' .. background_color .. '; color: #' .. text_color .. ';'
	elseif background_color then
		return 'background: #' .. background_color .. ';'
	else
		return ''
	end
end

function temperature_CSS(value, unit, palette)
	local palette = palettes[palette] or palettes.cool
	local value = tonumber(value)
	if value == nil then
		error("The function <span style=\"background-color: #EEE; font-family: monospace;\">temperature_CSS</span> is receiving a nil value")
	else
		if unit == 'C' then
			return color_CSS(temperature_color(palette, value))
		elseif unit == 'F' then
			return color_CSS(temperature_color(palette, convert(value, decimals, 'F')))
		else
			unit_error(unit or "nil")
		end
	end
end

--[[ ==== Cell, row, table generation ==== ]]
local output_formats = {
	high_low_average_F =
		{ first = "F",
		convert_units = "yes",
		unit_names = "no",
		color = "yes",
		small_font = "yes",
		sortable = "yes",
		decimals = "0",
		brackets = "yes",
		line_break = "auto", },
	high_low_average_C =
		{ first = "C",
		convert_units = "yes",
		unit_names = "no",
		color = "yes",
		small_font = "yes",
		sortable = "yes",
		decimals = "0",
		brackets = "yes",
		line_break = "auto", },
	high_low_F =
		{ first = "F",
		convert_units = "yes",
		unit_names = "no",
		color = "no",
		small_font = "yes",
		sortable = "no",
		decimals = "",
		brackets = "yes",
		line_break = "auto", },
	high_low_C =
		{ first = "C",
		convert_units = "yes",
		unit_names = "no",
		color = "no",
		small_font = "yes",
		sortable = "no",
		decimals = "0",
		brackets = "yes",
		line_break = "auto", },
	average_F =
		{ first = "F",
		convert_units = "yes",
		unit_names = "no",
		color = "yes",
		small_font = "yes",
		sortable = "no",
		decimals = "0",
		brackets = "yes",
		line_break = "auto", },
	average_C =
		{ first = "C",
		convert_units = "yes",
		unit_names = "no",
		color = "yes",
		small_font = "yes",
		sortable = "no",
		decimals = "0",
		brackets = "yes",
		line_break = "auto", },
	}

local function add_unit_names(value, unit)
	if not unit then unit = input_unit end
	if output_format.unit_names == "yes" then
		if check_for_string(value) then
			return value .. "&nbsp;" .. degree .. unit
		else
			return value -- Don't add a unit name to an empty string
		end
	else
		return value
	end
end

local function if_yes(parameter, realization1, realization2)
	if realization1 then
		if realization2 then
			if parameter == "yes" then
				parameter = { realization1, realization2 }
			else
				parameter = { "", "" }
			end
		else
			if parameter == "yes" then
				parameter = realization1
			else
				parameter = ""
			end
		end
	else
		parameter = ""
		add_message("<span style=\"background-color: #EEE; font-family: monospace;\">if_yes</span> needs at least one realization")
	end
	return parameter
end

function makeCell(output_format, a, b, c)
	local cell, cell_content = "", ""
	local color_CSS, other_CSS, title_attribute, sortkey, attribute_separator, converted_units_separator = "", "", "", "", "", "", ""
	local style_attribute, high_low_separator, brackets, values, converted_units = {"", ""}, {"", ""}, {"", ""}, {"", ""}, {"", ""}
	
	if check_for_number(output_format.decimals) then
		decimals = output_format.decimals
		--[[ Precision is the number of decimals in the first number of the last array.
			This may be a problem for data from Weatherbase,
			which seems to inappropriately remove .0 from numbers that have it. ]]
	else
		decimals = precision
	end
	
	if check_for_number(b) and check_for_number(a) then
		values, high_low_separator = { round(a, decimals), round(b, decimals) }, { thinSpace .. "/" .. thinSpace, if_yes(output_format.convert_units, thinSpace .. "/" .. thinSpace) }
	elseif check_for_number(a) then
		values = { round(a, decimals), "" }
	elseif check_for_number(c) then
		values = { round(c, decimals), "" }
	end
	if output_format.first == input_unit then
		if output_format.convert_units == "yes" then
			converted_units = { add_unit_names(convert(values[1], decimals), output_unit), add_unit_names(convert(values[2], decimals), output_unit) }
		end
		values = { add_unit_names(values[1]), add_unit_names(values[2]) }
	elseif output_format.first == "C" or output_format.first == "F" then
		if output_format.convert_units == "yes" then
			converted_units = { add_unit_names(values[1]), add_unit_names(values[2]) }
		end
		values = { add_unit_names(convert(values[1], decimals), output_unit), add_unit_names(convert(values[2], decimals), output_unit) }
	else
		if output_format.first == nil then
			output_format.first = "nil"
		end
		add_message("<span style=\"background-color: #EEE; font-family: monospace;\">" .. output_format.first .. "</span>, the value for <span style=\"background-color: #EEE; font-family: monospace;\">first</span> in <span style=\"background-color: #EEE; font-family: monospace;\">output_format</span> is not recognized.")
	end
	--[[
		Regarding line breaks:
		If there are two values, there will be at least three characters: 9/1.
		If there is one decimal, numbers will be three to five characters long
		and there will be 3 to 10 characters total even without unit conversion:
			1.1, 116.5/88.0.
		If there are units, that adds three characters per number: 25 °C/20 °C.
		In each of these cases, a line break is needed so that table cells are not too wide;
		even more so when more than one of these things are true.
		]]
	if output_format.convert_units == "yes" then
		brackets = if_yes(output_format.brackets, "(", ")" )
		if output_format.line_break == "auto" then
			if check_for_string(values[2]) or decimals ~= "0" or output_format.show_units == "yes" then
				converted_units_separator = "<br>"
			else
				converted_units_separator = "&nbsp;"
			end
		elseif output_format.line_break == "yes" then
			converted_units_separator = "<br>"
		elseif output_format.line_break == "no" then
			converted_units_separator = "&nbsp;"
		else
			error("Value for line_break not recognized")
		end
	end
	
	cell_content = values[1] .. high_low_separator[1] .. values[2] .. converted_units_separator .. brackets[1] .. converted_units[1] .. high_low_separator[2] .. converted_units[2] .. brackets[2]
	
	if check_for_number(c) then
		color_CSS = if_yes(output_format.color, temperature_CSS(c, input_unit, palette))
		if check_for_number(b) and check_for_number(a) then
			local attribute_value
			if output_format.first == input_unit then
				attribute_value = c
			else
				attribute_value = convert(c, decimals)
			end
			sortkey = if_yes(output_format.sortable, " data-sort-value=\"" .. attribute_value .. "\"")
			title_attribute = " title=\"Average temperature: " .. attribute_value .. " " .. degree .. output_format.first .. "\""
		end
	elseif check_for_number(b) then
		color_css = ""
	elseif check_for_number(a) then
		color_CSS = if_yes(output_format.color, temperature_CSS(a, input_unit, palette))
	else
		add_message("Neither a nor b nor c are strings.")
	end
	other_CSS = if_yes(output_format.small_font, "font-size: 85%;")
	if check_for_string(color_CSS) or check_for_string(other_CSS) then
		style_attribute = { "style=\"", "\"" }
	end
	
	if check_for_string(other_CSS) or check_for_string(color_CSS) or check_for_string(title_attribute) or check_for_string(sortkey) then
		attribute_separator = " | "
	end
	cell = "\n| " .. style_attribute[1] .. color_CSS .. other_CSS .. style_attribute[2] .. title_attribute .. sortkey .. attribute_separator .. cell_content
	return cell
end

function f.makeRow(frame)
	make_arrays(frame)
	local output = ""
	if frame.args[1] then
		output = "\n|-"
		output = output .. "\n! " .. frame.args[1]
		if frame.args[2] then
			output = output .. " !! " .. frame.args[2]
		end
	end
	if cell_format then
		output_format = cell_format
	end
	if a and b and c then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.high_low_average_F
			end
			output = output .. makeCell(output_format, a[i], b[i], c[i])
		end
	elseif a and b then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.high_low_F
			end
			output = output .. makeCell(output_format, a[i], b[i])
		end
	elseif a then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.average_F
			end
			output = output .. makeCell(output_format, a[i])
		end
	end
	output = mw.ustring.gsub(output, "([%p%s])-(%d)", "%1" .. minus .. "%2")
	return output
end

function f.makeTable(frame)
	make_arrays(frame)
	local output = "{| class=\"wikitable center nowrap\""
	if cell_format then
		output_format = cell_format
	end
	if a and b and c then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.high_low_average_F
			end
			output = output .. makeCell(output_format, a[i], b[i], c[i])
		end
	elseif a and b then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.high_low_F
			end
			output = output .. makeCell(output_format, a[i], b[i])
		end
	elseif a then
		for i = 1, length do
			if not output_format then
				output_format = output_formats.average_F
			end
			output = output .. makeCell(output_format, a[i])
		end
	end
	output = mw.ustring.gsub(output, "([%p%s])-(%d)", "%1" .. minus .. "%2")
		--[[  Makes sure that hyphens in "data-sort-type" are not replaced with minuses.
				If Lua had (?<=), a capture would not be necessary.  ]]
	output = output .. "\n|}"
	if show then
		output = output .. "\n\n<span style=\"color: red; font-size: 80%; line-height: 100%;\">" .. message .. "</span>"
	end
	return output
end

return f