local p = {} -- Package to be exported



-- Local version of string formatting function

local format = mw.ustring.format

-- Local version of string trimming function

local trim = mw.text.trim

-- Store this function in a local variable to avoid expensive table lookups.

local insert = table.insert



-- mw.html object for the generated row

local row

-- Default row span for all columns (`jspan` = "junction span")

local jspan

-- Any error messages produced that will be added to the output

local errorMsg = {}



-- A specification for self-closing HTML tag.

local selfClosing = {selfClosing = true}



---

-- Converts the distance specified in unit from `unit` specified in `unitdef`

-- to the other supported unit.

local function convert(unit, unitdef)

	if unit == nil or unitdef == nil then return {} end



	-- Import module to convert length.

	local util = require("Module:Road data/util")

	local lengths = util.convertLengths({[unitdef = unit})

	if lengths.error then -- An error occurred during conversion.

		-- Add the transcluding page to an error tracking category.

		local page = mw.title.getCurrentTitle() -- Get transcluding page's title

		local pagename = page.prefixedText -- Extract page's full title as string

		-- Create category string

		local category = format("[[Category:Jctint template using non-numeric parameter values|# %s]]", pagename)

		insert(errorMsg, category) -- Add error category to error message table.

	end

	return lengths

end



--- Creates cells for the location columns.

local function locations(args)

	-- Unitary, e.g., state line

	local unitary = args.unitary -- Value to span all of the location columns

	if unitary then

		-- Text alignment of the cell contents, default to "left".

		local align = args.unitary_align or 'left'

		row:tag('td') -- Create unitary cell

			:attr('colspan', 3) -- spanning three possible columns

			:css('text-align', align)

			:wikitext(unitary) -- Store the contents of unitary in the cell.

		return

	end



	-- Create cells for regular location columns.



	-- Region, for disambiguation and potentially for display

	local region = args.region

	if region or args.region_special then

		-- Row span for region; must be specified to display a region cell.

		local regionSpan = args.regionspan

		if regionSpan then

			row:tag('td') -- Create a region cell

				:attr('rowspan', regionSpan)

				-- Store region text in the cell.

				-- `region_special` argument overrides wikilinked `region` argument.

				:wikitext(args.region_special or format("[[%s]]", region))

		end

	end



	-- Primary topic requires no specialization to supplied locations.

	local primaryTopic = args.primary_topic ~= 'no'



	-- Note below main text in the next column

	local sub1note = args.sub1_note -- check existence later

	-- Row span for the last location column, default to `jspan`

	local sub2span = args.sub2span or jspan



	-- Independent city

	local indepCityText -- Value to span both subdivision columns.

	if args.indep_city_special then

		indepCityText = args.indep_city_special -- Overrides `indep_city` argument.

	elseif args.indep_city then

		local indepCity = args.indep_city

		local cityLink -- Wikilink for independent city

		if primaryTopic then

			cityLink = format('[[%s]]', indepCity)

		elseif region then

			-- Specialize independent city to the region.

			cityLink = format('[[%s, %s|%s]]', indepCity, region, indepCity)

		end

		if cityLink then

			indepCityText = "[[Independent city|City]] of " .. cityLink

		end

	end

	if indepCityText then -- Display independent city.

		-- Text alignment of the cell contents, default to "left".

		local align = args.indep_city_align or 'left'

		local indepCityCell = row:tag('td') -- Create independent city cell

			:attr('colspan', 2) -- spanning two columns

			:attr('rowspan', sub2span) -- with the calculated row span.

			:css('text-align', align)

			:wikitext(indepCityText) -- Store the independent city in the cell.

		if sub1note then -- A note is provided.

			indepCityCell:tag('br', selfClosing) -- Add a line break to the cell.

			-- Add the note to the cell, within an HTML <small> tag.

			indepCityCell:tag('small'):wikitext(sub1note)

		end

		return

	end



	-- Create two cells for the first- and second-level subdivisions.



	-- First-level subdivision, e.g., county

	-- Name of the type of subdivision, e.g., "County" and "Parish"

	local sub1name = args.sub1name -- check existence later

	local sub1Text -- Value for first-level subdivision column.

	if args.sub1_special then

		sub1Text = args.sub1_special -- Overrides `sub1` argument.

	elseif args.sub1 then

		local sub1 = args.sub1

		if primaryTopic then

			-- Add type (if specified) to wikilink for first-level subdivision.

			local sub1Link = sub1name and format("%s %s", sub1, sub1name) or sub1

			sub1Text = format('[[%s|%s]]', sub1Link, sub1)

		elseif region and sub1name then

			-- Add type to first-level subdivision.

			local sub1Typed = trim(format('%s %s', sub1, sub1name))

			-- Specialize first-level subdivision, with type added, to the region.

			sub1Text = format('[[%s, %s|%s]]', sub1Typed, region, sub1)

		end

	end

	if sub1Text then -- Display first-level subdivision.

		-- Row span for first-level subdivision, default to `jspan`.

		local sub1span = args.sub1span or jspan

		local sub1Cell = row:tag('td') -- Create first-level subdivision cell

			:attr('rowspan', sub1span) -- with the calculated row span.

			:wikitext(sub1Text) -- Store the first-level subdivision in the cell.

		if sub1note then -- A note is provided.

			sub1Cell:tag('br', selfClosing) -- Add a line break to the cell.

			-- Add the note to the cell, within an HTML <small> tag.

			sub1Cell:tag('small'):wikitext(sub1note)

		end

	end



	-- Second-level subdivision, e.g., city and town

	local sub2Text -- Value for second-level subdivision column.

	if args.sub2_special then

		sub2Text = args.sub2_special -- Overrides `sub2` argument.

	elseif args.sub2 then

		local sub2 = args.sub2

		if sub2 == "none" or sub2 == "&nbsp;" then

			sub2Text = "&#8203;" -- Zero-width space

		elseif primaryTopic then

			sub2Text = format("[[%s]]", sub2)

		else

			local sub2Link = {sub2}

			local sub2Name = sub2

			-- Type of area, e.g., city and village, as a form of disambiguation

			local area = args.area

			if area then

				insert(sub2Link, format(' (%s)', area)) -- Add area to wikilink.

				local areas = { -- table of different area types

					borough = "Borough",

					city = "City",

					community = "Community",

					CDP = "Community",

					hamlet = "Hamlet",

					town = "Town",

					village = "Village",

					"unorganized territory" = "Unorganized Territory"

				}

				-- Add area name to displayed wikitext.

				sub2Name = format("%s of %s", areasarea], sub2Name)

			end

			insert(sub2Link, ", ")

			-- Some second-level subdivisions are not unique in a given region.

			-- `sub1dab` is the first-level subdivision to be used for disambiguation.

			local sub1dab = args.sub1dab 

			if sub1dab and sub1name then

				insert(sub2Link, trim(format('%s %s', sub1dab, sub1name)) .. ", ")

			end

			if region then

				insert(sub2Link, region) -- Add region to wikilink

			end



			sub2Text = format("[[%s|%s]]", table.concat(sub2Link), sub2Name)

		end

	end

	if sub2Text then -- Display second-level subdivision.

		row:tag('td') -- Create second-level subdivision cell

			:attr('rowspan', sub2span) -- with the calculated row span.

			:wikitext(sub2Text) -- Store the second-level subdivision in the cell.

	end

end



--- Creates cells for the distance columns.

local function units(args)

	-- Alternate units, e.g., California's postmiles.

	local alt_unit = args.altunit

	if alt_unit then -- Alternate units override standard units.

		-- Row span (`auspan` = "alt[ernate] unit span")

		local auspan = args.auspan or jspan

		-- Create the alternate unit cell as a header cell for the row,

		-- since it is usually unique within the table.

		row:tag('th'):attr('scope', 'row')

			:css('text-align', 'right')

			:attr('rowspan', auspan)

			:wikitext(alt_unit) -- Store the contents of alt_unit in the cell.

	else

		-- Convert numeric distances to a secondary unit, and display both units.

		-- Distance in the primary unit, or 'none'

		local unit = args.unit

		-- If `unit` is "none", no cells are displayed.

		if unit == "none" then return end

		local unitdef = args.unitdef or "km" -- The primary unit ('mi' or 'km')

		-- Convert and format the distance.

		local lengths = convert(unit, unitdef)

		-- Row span (`uspan` = "unit span")

		local uspan = args.uspan or jspan

		-- Create the primary unit cell as a header cell for the row,

		-- since it is usually unique within the table.

		local primary = row:tag('th'):attr('scope', 'row')

			:css('text-align', 'right')

			:attr('rowspan', uspan)

			-- Store the primary distance and any conversion error message in the cell.

			:wikitext(lengthslengths.orig], lengths.error)

		local secondary = row:tag('td') -- Create the secondary unit cell.

			:css('text-align', 'right')

			:css('background-color', '#eaecf0')

			:attr('rowspan', uspan)

			:wikitext(lengthslengths.comp]) -- Store the secondary distance in the cell.



		local unit_ref = args.unit_ref

		if unit_ref then -- A reference is provided for the distance.

			primary:wikitext(unit_ref) -- Add reference to the primary distance cell.

		end



		local unit2 = args.unit2

		if unit2 then -- A second distance is provided.

			local line = args.line -- A horizontal rule may be requested between the distances.

			if line then

				-- Add a horizontal rule to both cells.

				primary:tag('hr', selfClosing)

				secondary:tag('hr', selfClosing)

			else

				-- Add an en-dash and a line break to both cells.

				primary:wikitext('–'):tag('br', selfClosing)

				secondary:wikitext('–'):tag('br', selfClosing)

			end

			-- Convert and format the second distance.

			local lengths2 = convert(unit2, unitdef)

			-- Add the second distance and any conversion error message to the primary distance cell.

			primary:wikitext(lengths2lengths2.orig], lengths2.error)

			-- Add the converted second distance to the secondary distance cell.

			secondary:wikitext(lengths2lengths2.comp])

			end

		

		local unit2_ref = args.unit2_ref

		if unit2_ref then -- A reference is provided for the distance.

			primary:wikitext(unit2_ref) -- Add reference to the primary distance cell.

		end

	end

end



-- Color specified by any supplied type

local color

-- Tooltip specified by any supplied type

local title



--- Apply any type-derived coloring and tooltip to the given cell.

local function applyTypeStyle(cell)

	cell:attr('title', title):css('background-color', color)

end



--- Creates a cell for places, such as bridges and rest areas.

local function place(args)

	local place = args.place -- Contents of the place cell

	-- Do nothing if `place` is "none"

	if place == "none" then return end

	local colspan = 2 -- Initial column span

	local exit = args1 -- Whether this table has exit number columns

	local named = args2 -- Whether this table has named junction column

	-- Adjust column span

	if exit == "old" then colspan = colspan + 2

	elseif exit == "exit" then colspan = colspan + 1

	end

	if named == "name" then colspan = colspan + 1 end

	-- Row span (`pspan` = "place span")

	local pspan = args.pspan or jspan

	local placeCell = row:tag('td') -- Create place cell

		:css('text-align', 'center')

		:attr('colspan', colspan)

		:attr('rowspan', pspan)

		:wikitext(place) -- Store the place in the cell

	applyTypeStyle(placeCell)

end



--- Creates cells for exit number and named junction columns.

local function exits(args)

	local exit = args1 -- 'exit', 'old', or nil

	local named = args2 -- 'name' or nil



	if exit == 'old' then -- Add old exit number cell

		-- Row span (`ospan` = "old span")

		local ospan = args.ospan or jspan

		row:tag('td') -- Create old exit number cell

			:css('text-align', 'center')

			:css('background-color', '#d3d3d3')

			:attr('title', 'Former exit number')

			:attr('rowspan', ospan)

			:wikitext(args.old) -- Store the old exit number in the cell

	end



	if exit then -- "exit" or "old" is defined; add current exit number cell

		-- Row span (`espan` = "exit span")

		local espan = args.espan or jspan

		local exitCell = row:tag('td') -- Create exit number cell

			:css('text-align', 'center')

			:attr('rowspan', espan)

			:wikitext(args.exit) -- Store the exit number in the cell

		applyTypeStyle(exitCell)

	end



	if named then -- Junction list has a junction name column

		local namespan = args.namespan or jspan -- Row span

		local nameCell = row:tag('td') -- Create junction name cell

			:attr('rowspan', namespan)

			:wikitext(args.name) -- Store the junction name in the cell

		applyTypeStyle(nameCell)

	end

end



--- Creates cell for the destinations column.

local function destinations(args)

	local road = args.road -- Contents of the destinations cell

	-- Do nothing if `road` is "none"

	if road == "none" then return end

	-- Column span (`rcspan` = "road column span"), default to 1

	local rcspan = args.rcspan or 1

	-- Row span (`rspan` = "road span")

	local rspan = args.rspan or jspan

	local destCell = row:tag('td') -- Create destination cell

		:attr('colspan', rcspan)

		:attr('rowspan', rspan)

		:wikitext(road) -- Store the destination in the cell

	applyTypeStyle(destCell)

end



--- Creates cell for the notes column.

local function notes(args)

	local notes = args.notes -- Contents of the notes cell

	-- Do nothing if `notes` is "none"

	if notes == "none" then return end

	-- Row span (`nspan` = "notes span")

	local nspan = args.nspan or jspan

	local notesCell = row:tag('td') -- Create notes cell

		:attr('rowspan', nspan)

		:wikitext(notes) -- Store the notes in the cell

	applyTypeStyle(notesCell)

end



---

-- Returns a row in the junction list.

-- Accessible from other Lua modules

function p._jctint(args)

	jspan = args.jspan or 1 -- Global row span for all columns; defaults to 1

	-- {{{type}}} argument to determine color and tooltips

	local argType = args.type

	if argType then -- {{{type}}} was passed

		-- Type-based data for colors and tooltips

		if argType == 'mplex' then

			local page = mw.title.getCurrentTitle() -- Get transcluding page's title

			local pagename = page.prefixedText -- Extract page's full title as string

			insert(errorMsg,

				format("[[Category:Jctint template with invalid type|$ %s]]", pagename))

		end

		local types = mw.loadData("Module:Road data/RJL types")

		local typeData = typesstring.lower(argType)] -- Retrieve the type data

		if typeData then

			color = typeData.color -- Store the color globally

			title = typeData.jctint -- Store the tooltip globally

		else

			-- Add error category to error message table.

			local page = mw.title.getCurrentTitle() -- Get transcluding page's title

			local pagename = page.prefixedText -- Extract page's full title as string

			insert(errorMsg,

				format("[[Category:Jctint template with invalid type|%s]]", pagename))

		end

	end



	local root = mw.html.create() -- Create the root mw.html object to return

	-- Create the table row and store it globally

	row = root:tag('tr'):css('text-align', 'left')



	locations(args) -- Handle location arguments

	units(args) -- Handle distance arguments

	if args.place then -- {{{place}}} spans all columns to the right of the distances

		place(args) -- Create cell for place

	else

		exits(args) -- Handle exit/named junction arguments

		destinations(args) -- Handle destinations

		notes(args) -- Handle notes

	end



	-- Return the HTML code in the mw.html object as a string, plus any error messages

	return tostring(root) .. table.concat(errorMsg)

end



--- Entry function for {{jctint/core}}

function p.jctint(frame)

	-- Import module function to work with passed arguments

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

	-- Gather passed arguments into easy-to-use table

	local args = getArgs(frame)

	return p._jctint(args)

end



return p -- Return package