Module:Box-header explained

local getArgs = require('Module:Arguments').getArgs

local p = ---------- Config data ----------local namedColours = mw.loadData('Module:Box-header/colours')local modes = local min_contrast_ratio_normal_text = 7 -- i.e 7:1local min_contrast_ratio_large_text = 4.5 -- i.e. 4.5:1

-- Template parameter aliases-- Specify each as either a single value, or a table of values-- Aliases are checked left-to-right, i.e. `['one'] = ` is equivalent to using `` in a templatelocal parameterAliases =

---------- Dependecies ----------local colourContrastModule = require('Module:Color contrast')local hex = require('luabit.hex')

---------- Utility functions ----------local function getParam(args, parameter) if args[parameter] then return args[parameter] end local aliases = parameterAliases[parameter] if not aliases then return nil end if type(aliases) ~= 'table' then return args[aliases] end for _, alias in ipairs(aliases) do if args[alias] then return args[alias] end end return nilend

local function setCleanArgs(argsTable) local cleanArgs = for key, val in pairs(argsTable) do if type(val)

'string' then val = val:match('^%s*(.-)%s*$') if val ~= then cleanArgs[key] = val end else cleanArgs[key] = val end end return cleanArgsend

-- Merge two tables into a new table. If the are any duplicate keys, the values from the second overwrite the values from the first.local function mergeTables(first, second) local merged = for key, val in pairs(first) do merged[key] = val end for key, val in pairs(second) do merged[key] = val end return mergedend

local function toOpenTagString(selfClosedHtmlObject) local closedTagString = tostring(selfClosedHtmlObject) local openTagString = mw.ustring.gsub(closedTagString, ' />$', '>') return openTagStringend

local function normaliseHexTriplet(hexString) if not hexString then return nil end local hexComponent = mw.ustring.match(hexString, '^#(%x%x%x)$') or mw.ustring.match(hexString, '^#(%x%x%x%x%x%x)$') if hexComponent and #hexComponent

6 then return mw.ustring.upper(hexString) end if hexComponent and #hexComponent

3 then local r = mw.ustring.rep(mw.ustring.sub(hexComponent, 1, 1), 2) local g = mw.ustring.rep(mw.ustring.sub(hexComponent, 2, 2), 2) local b = mw.ustring.rep(mw.ustring.sub(hexComponent, 3, 3), 2) return '#' .. mw.ustring.upper(r .. g .. b) end return nilend

---------- Conversions ----------local function decimalToPaddedHex(number) local prefixedHex = hex.to_hex(tonumber(number)) -- prefixed with '0x' local padding = #prefixedHex

3 and '0' or return mw.ustring.gsub(prefixedHex, '0x', padding)endlocal function hexToDecimal(hexNumber) return tonumber(hexNumber, 16)endlocal function RGBtoHexTriplet(R, G, B) return '#' .. decimalToPaddedHex(R) .. decimalToPaddedHex(G) .. decimalToPaddedHex(B)endlocal function hexTripletToRGB(hexTriplet) local R_hex, G_hex, B_hex = string.match(hexTriplet, '(%x%x)(%x%x)(%x%x)') return hexToDecimal(R_hex), hexToDecimal(G_hex), hexToDecimal(B_hex)endlocal function HSVtoRGB(H, S, V) -- per HSL and HSV#Converting_to_RGB local C = V * S local H_prime = H / 60 local X = C * (1 - math.abs(math.fmod(H_prime, 2) - 1)) local R1, G1, B1 if H_prime <= 1 then R1 = C G1 = X B1 = 0 elseif H_prime <= 2 then R1 = X G1 = C B1 = 0 elseif H_prime <= 3 then R1 = 0 G1 = C B1 = X elseif H_prime <= 4 then R1 = 0 G1 = X B1 = C elseif H_prime <= 5 then R1 = X G1 = 0 B1 = C elseif H_prime <= 6 then R1 = C G1 = 0 B1 = X end local m = V - C local R = R1 + m local G = G1 + m local B = B1 + m

local R_255 = math.floor(R*255) local G_255 = math.floor(G*255) local B_255 = math.floor(B*255) return R_255, G_255, B_255endlocal function RGBtoHue(R_255, G_255, B_255) -- per HSL and HSV#Hue and chroma local R = R_255/255 local G = G_255/255 local B = B_255/255

local M = math.max(R, G, B) local m = math.min(R, G, B) local C = M - m local H_prime if C

0 then return null elseif M

R then H_prime = math.fmod(((G - B)/C + 6), 6) -- adding six before taking mod ensures positive value elseif M

G then H_prime = (B - R)/C + 2 elseif M

B then H_prime = (R - G)/C + 4 end local H = 60 * H_prime return Hendlocal function nameToHexTriplet(name) if not name then return nil end local codename = mw.ustring.gsub(mw.ustring.lower(name), ' ', ) return namedColours[codename]end

---------- Choose colours ----------local function calculateColours(H, S, V, minContrast) local bgColour = RGBtoHexTriplet(HSVtoRGB(H, S, V)) local textColour = colourContrastModule._greatercontrast local contrast = colourContrastModule._ratio if contrast >= minContrast then return bgColour, textColour elseif textColour

'#FFFFFF' then -- make the background darker and slightly increase the saturation return calculateColours(H, math.min(1, S+0.005), math.max(0, V-0.03), minContrast) else -- make the background lighter and slightly decrease the saturation return calculateColours(H, math.max(0, S-0.005), math.min(1, V+0.03), minContrast) endend

local function makeColours(hue, modeName) local mode = modes[modeName] local isGrey = not(hue) if isGrey then hue = 0 end

local borderSat = isGrey and modes.grey.sat or 0.15 local border = RGBtoHexTriplet(HSVtoRGB(hue, borderSat, 0.75))

local titleSat = isGrey and modes.grey.sat or mode.sat local titleBackground, titleForeground = calculateColours(hue, titleSat, mode.val, min_contrast_ratio_large_text)

local contentSat = isGrey and modes.grey.sat or modes.content.sat local contentBackground, contentForeground = calculateColours(hue, contentSat, modes.content.val, min_contrast_ratio_normal_text)

return border, titleForeground, titleBackground, contentForeground, contentBackgroundend

local function findHue(colour) local colourAsNumber = tonumber(colour) if colourAsNumber and (-1 < colourAsNumber) and (colourAsNumber < 360) then return colourAsNumber end

local colourAsHexTriplet = normaliseHexTriplet(colour) or nameToHexTriplet(colour) if colourAsHexTriplet then return RGBtoHue(hexTripletToRGB(colourAsHexTriplet)) end

return nullend

local function normaliseMode(mode) if not mode or not modes[mw.ustring.lower(mode)] or mw.ustring.lower(mode)

'grey' then return 'normal' end return mw.ustring.lower(mode)end---------- Build output ----------local function boxHeaderOuter(args) local baseStyle =

local tag = mw.html.create('div',) :addClass('box-header-title-container') :addClass('flex-columns-noflex') :css(baseStyle) :css('border-width', (getParam(args, 'border-top') or getParam(args, 'border-width') or '1') .. 'px ' .. (getParam(args, 'border-width') or '1') .. 'px 0') :css('padding-top', getParam(args, 'padding-top') or '.1em') :css('padding-left', getParam(args, 'padding-left') or '.1em') :css('padding-right', getParam(args, 'padding-right') or '.1em') :css('padding-bottom', getParam(args, 'padding-bottom') or '.1em') :css('moz-border-radius', getParam(args, 'title-border-radius') or '0') :css('webkit-border-radius', getParam(args, 'title-border-radius') or '0') :css('border-radius', getParam(args, 'title-border-radius') or '0') return toOpenTagString(tag)end

local function boxHeaderTopLinks(args) local style = local tag = mw.html.create('div',) :addClass('plainlinks noprint') :css(style) return toOpenTagString(tag)end

local function boxHeaderEditLink(args) local page = getParam(args, 'editpage') if not page or page

'' then return end local style = local tag = mw.html.create('span') :css(style) :wikitext('edit') local linktext = tostring(tag) local linktarget = tostring(mw.uri.fullUrl(page,)) return '[' .. linktarget .. ' ' .. linktext .. '] 'end

local function boxHeaderViewLink(args) local style = local tag = mw.html.create('span') :css(style) :wikitext('view') local linktext = tostring(tag) local linktarget = ':' .. getParam(args, 'viewpage') return "· ' .. linktext .. ' 'end

local function boxHeaderTitle(args) local baseStyle = local tagName = getParam(args, 'SPAN') and 'span' or 'h2' local tag = mw.html.create(tagName) :css(baseStyle) :css('padding-bottom', '.1em') :wikitext(getParam(args, 'title')) if getParam(args, 'extra') then local rules = mw.text.split(getParam(args, 'extra'), ';', true) for _, rule in pairs(rules) do local parts = mw.text.split(rule, ':', true) local prop = parts[1] local val = parts[2] if prop and val then tag:css(prop, val) end end end return tostring(tag)end

local function boxBody(args) local baseStyle = local tag = mw.html.create('div',) :css(baseStyle) :css('border-top-width', (getParam(args, 'border-top') or '1') .. 'px') :css('padding-top', getParam(args, 'padding-top') or '.3em') :css('border-radius', getParam(args, 'border-radius') or '0') return toOpenTagString(tag)end

local function contrastCategories(args) local cats =

local titleText = nameToHexTriplet(getParam(args, 'titleforeground')) or normaliseHexTriplet(getParam(args, 'titleforeground')) or '#000000' local titleBackground = nameToHexTriplet(getParam(args, 'titlebackground')) or normaliseHexTriplet(getParam(args, 'titlebackground')) or '#bcbcbc' local titleContrast = colourContrastModule._ratio local insufficientTitleContrast = type(titleContrast)

'number' and (titleContrast < min_contrast_ratio_large_text)

local bodyText = nameToHexTriplet(getParam(args, 'foreground')) or normaliseHexTriplet(getParam(args, 'foreground')) or '#000000' local bodyBackground = nameToHexTriplet(getParam(args, 'background')) or normaliseHexTriplet(getParam(args, 'background')) or '#fefeef' local bodyContrast = colourContrastModule._ratio local insufficientBodyContrast = type(bodyContrast)

'number' and (bodyContrast < min_contrast_ratio_normal_text)

if insufficientTitleContrast and insufficientBodyContrast then return '' elseif insufficientTitleContrast then return '' elseif insufficientBodyContrast then return '' else return endend

---------- Main functions / entry points ----------

-- Entry point for templates (manually-specified colours)function p.boxHeader(frame) local args = getArgs(frame) local page = args.editpage if not args.editpage or args.editpage