-- the goal of this module is to standardize creating imagemaps for yearly Senate and Gubernatorial elections in the United States.
local utils = require("Module:US elections imagemap/utils") -- utilities such as a string splitting function
local data = require("Module:US elections imagemap/data") -- data such as shapes of states; do NOT change to mw.loadData as that breaks excluded-states

local stateshapes = data.stateshapes
local cycles = data.cycles
local statenames = data.statenames

local p = {}

function p.makeMap(frame)
	local states = cycles[frame.args.cycle] or error("error: invalid/no cycle specified") -- require to specify a cycle
	local extrastates = utils.split(frame.args.extra_states or "", ";") -- extra states to add
	local extralines = utils.split(frame.args.extra_lines or "", ";") -- extra raw lines to add
	local excludedstates = utils.split(frame.args.excluded_states or "", ";") -- states to EXCLUDE
	for _, excludedstate in ipairs(excludedstates) do
		for k, state in ipairs(states) do
			if state == excludedstate then
		        table.remove(states, k) -- remove the state from the table. this doesn't remove it if it's included in extra_states
		    end
		end
	end
	local stateoverrides = utils.split(frame.args.state_overrides or "", ";") -- state overrides for links (for example, linking to a recall election)
	local overrides = {} -- overrides should be an array of STATE="Override"
	for _, override in ipairs(stateoverrides) do
		local overridear = utils.split(override,"=")
		overrides[overridear[1]] = " [[" .. overridear[2] .. "]]\r\n\r\n" -- format the same as normal links
	end
	local linktemplatearg = frame.args.link_template or error("error: no link template specified") -- require a link template
	local linktemplate = " [[" .. linktemplatearg .. "]]\r\n\r\n" -- make it a wikilink, also the space is necessary to separate from the shape data
	local imagemap = "\r\n\r\n" -- start the imagemap
	for _, line in ipairs(extralines) do -- for each extra line. these have to come before normal lines to override them (otherwise, special elections for example don't work)
		imagemap = imagemap .. line .. "\r\n\r\n" -- append the extra line
	end
	for _, state in ipairs(extrastates) do -- for each extrastate - do first, in case of conflicts (like special elections, see above)
		statename = statenames[state] or error (state) -- if a state isn't in the list for some reason, this will tell which one
		local link = overrides[state] or string.gsub(linktemplate, "STATE", statenames[state]) -- check for individual state override, if not, swap the state name into the link template
		imagemap = imagemap .. stateshapes[state] .. link -- add the link (which already contains the needed newline)
	end
	for _, state in ipairs(states) do -- for each state
		statename = statenames[state] or error (state) -- if a state isn't in the list for some reason, this will tell which one
		local link = overrides[state] or string.gsub(linktemplate, "STATE", statenames[state]) -- check for individual state override, if not, swap the state name into the link template
		imagemap = imagemap .. stateshapes[state] .. link -- add the link (which already contains the needed newline)
	end
	return imagemap
end

return p