Module:Coordinates

Documentation for this module may be created at Module:Coordinates/doc
--[[
This module is intended to replace the functionality of {{Coord}} and related
templates.  It provides several methods, including

{{#Invoke:Coordinates | coord }} : General function formatting and displaying
coordinate values.

{{#Invoke:Coordinates | dec2dms }} : Simple function for converting decimal
degree values to DMS format.

{{#Invoke:Coordinates | dms2dec }} : Simple function for converting DMS format
to decimal degree format.

{{#Invoke:Coordinates | link }} : Export the link used to reach the tools

]]

math_mod = require( "Module:Math" );
globalFrame = nil
coordinates = {};

current_page = mw.title.getCurrentTitle()
page_name = mw.uri.encode( current_page.prefixedText, 'WIKI' );
coord_link = '//tools.wmflabs.org/geohack/geohack.php?pagename=' .. page_name .. '&params='

--[[ Helper function, replacement for {{coord/display/title}} ]]
function displaytitle (s, notes)
	local l = "[[Geographic coordinate system|Coordinates]]: " .. s
	local co = '<span id="coordinates">' .. l .. notes .. '</span>';
	return '<span style="font-size: small;">' .. co .. '</span>';
end

--[[ Helper function, Replacement for {{coord/display/inline}} ]]
function displayinline (s, notes)
	return s .. notes	
end

--[[ Helper function, used in detecting DMS formatting ]]
local dmsTest = function(first, second)
	local concatenated = first:upper() .. second:upper();
	
	if concatenated == "NE" or concatenated == "NW" or concatenated == "SE" or concatenated == "SW" or
		concatenated == "EN" or concatenated == "WN" or concatenated == "ES" or concatenated == "WS" then
		return true;
	end
	return false;
end

--[[
parseDec

Transforms decimal format latitude and longitude into the a
structure to be used in displaying coordinates
]]
function parseDec( lat, long, format )
	local coordinateSpec = {}
	local errors = {}
	
	if long == "" or long == nil then
		return nil, {{"parseDec", "Missing longitude"}}
	end
	
	errors = validate( lat, nil, nil, long, nil, nil, 'parseDec', false );	
	coordinateSpec["dec-lat"]  = lat;
	coordinateSpec["dec-long"] = long;

	local mode = coordinates.determineMode( lat, long );
	coordinateSpec["dms-lat"]  = convert_dec2dms( lat, "N", "S", mode)  -- {{coord/dec2dms|{{{1}}}|N|S|{{coord/prec dec|{{{1}}}|{{{2}}}}}}}
	coordinateSpec["dms-long"] = convert_dec2dms( long, "E", "W", mode)  -- {{coord/dec2dms|{{{2}}}|E|W|{{coord/prec dec|{{{1}}}|{{{2}}}}}}}	
	
	if format ~= "" then
		coordinateSpec.default = format
	else
		coordinateSpec.default = "dec"
	end

	return coordinateSpec, errors
end

--[[ Helper function, handle optional args. ]]
function optionalArg(arg, suplement)
	if arg ~= nil and arg ~= "" then
		return arg .. suplement
	end
	return ""
end

--[[
parseDMS

Transforms degrees, minutes, seconds format latitude and longitude 
into the a structure to be used in displaying coordinates
]]
function parseDMS( lat_d, lat_m, lat_s, lat_f, long_d, long_m, long_s, long_f, format )
	local coordinateSpec = {}
	local errors = {}
	
	lat_f = lat_f:upper();
	long_f = long_f:upper();
	
	-- Check if specified backward
	if lat_f == 'E' or lat_f == 'W' then
		local t_d, t_m, t_s, t_f;
		t_d = lat_d;
		t_m = lat_m;
		t_s = lat_s;
		t_f = lat_f;
		lat_d = long_d;
		lat_m = long_m;
		lat_s = long_s;
		lat_f = long_f;
		long_d = t_d;
		long_m = t_m;
		long_s = t_s;
		long_f = t_f;
	end	
	
	errors = validate( lat_d, lat_m, lat_s, long_d, long_m, long_s, 'parseDMS', true );
	if long_d == nil or long_d == "" then
		table.insert(errors, {"parseDMS", "Missing longitude" })
	end
	
	if lat_m == nil and lat_s == nil and long_m == nil and long_s == nil and #errors == 0 then 
		if math_mod._precision( lat_d ) > 0 or math_mod._precision( long_d ) > 0 then
			if lat_f:upper() == 'S' then 
				lat_d = '-' .. lat_d;
			end
			if long_f:upper() == 'W' then 
				long_d = '-' .. long_d;
			end	 
			
			return parseDec( lat_d, long_d, format );
		end		
	end   
	
	coordinateSpec["dms-lat"]  = lat_d.."°"..optionalArg(lat_m,"′") .. optionalArg(lat_s,"″") .. lat_f
	coordinateSpec["dms-long"] = long_d.."°"..optionalArg(long_m,"′") .. optionalArg(long_s,"″") .. long_f
	coordinateSpec["dec-lat"]  = convert_dms2dec(lat_f, lat_d, lat_m, lat_s) -- {{coord/dms2dec|{{{4}}}|{{{1}}}|0{{{2}}}|0{{{3}}}}}
	coordinateSpec["dec-long"] = convert_dms2dec(long_f, long_d, long_m, long_s) -- {{coord/dms2dec|{{{8}}}|{{{5}}}|0{{{6}}}|0{{{7}}}}}

	if format ~= "" then
		coordinateSpec.default = format
	else
		coordinateSpec.default = "dms"
	end   

	return coordinateSpec, errors
end

--[[
specPrinter

Output formatter.  Takes the structure generated by either parseDec
or parseDMS and formats it for inclusion on Wikipedia.
]]
function specPrinter(args, coordinateSpec)
	local uriComponents = coordinateSpec["param"]
	if uriComponents == "" then
		-- RETURN error, should never be empty or nil
		return "ERROR param was empty"
	end
	if args["name"] ~= "" and args["name"] ~= nil then
		uriComponents = uriComponents .. "&title=" .. mw.uri.encode(coordinateSpec["name"])
	end
	
	local geodmshtml = '<span class="geo-dms" title="Maps, aerial photos, and other data for this location">'
			 .. '<span class="latitude">' .. coordinateSpec["dms-lat"] .. '</span> '
			 .. '<span class="longitude">' ..coordinateSpec["dms-long"] .. '</span>'
			 .. '</span>'

	local lat = tonumber( coordinateSpec["dec-lat"] ) or 0
	if lat < 0 then
		-- FIXME this breaks the pre-existing precision
		geodeclat = coordinateSpec["dec-lat"]:sub(2) .. "°S"
	else
		geodeclat = (coordinateSpec["dec-lat"] or 0) .. "°N"
	end

	local long = tonumber( coordinateSpec["dec-long"] ) or 0
	if long < 0 then
		-- FIXME does not handle unicode minus
		geodeclong = coordinateSpec["dec-long"]:sub(2) .. "°W"
	else
		geodeclong = (coordinateSpec["dec-long"] or 0) .. "°E"
	end
	
	local geodechtml = '<span class="geo-dec" title="Maps, aerial photos, and other data for this location">'
			 .. geodeclat .. ' '
			 .. geodeclong
			 .. '</span>'

	local geonumhtml = '<span class="geo">'
			 .. coordinateSpec["dec-lat"] .. '; '
			 .. coordinateSpec["dec-long"]
			 .. '</span>'

	local inner;
	inner = '<span class="' .. displayDefault(coordinateSpec["default"], "dms" ) .. '">' .. geodmshtml .. '</span>'
				.. '<span class="geo-multi-punct">&#xfeff; / &#xfeff;</span>'
				.. '<span class="' .. displayDefault(coordinateSpec["default"], "dec" ) .. '">';

	if args["name"] == "" or args["name"] == nil then
		inner = inner .. geodechtml 
				.. '<span style="display:none">&#xfeff; / ' .. geonumhtml .. '</span></span>'
	else
		inner = inner .. '<span class="vcard">' .. geodechtml 
				.. '<span style="display:none">&#xfeff; / ' .. geonumhtml .. '</span>'
				.. '<span style="display:none">&#xfeff; (<span class="fn org">'
				.. args["name"] .. '</span>)</span></span></span>'
	end

	return '<span class="plainlinks nourlexpansion">' .. 
		'[' .. coord_link .. uriComponents .. ' ' .. inner .. ']' .. '</span>'
end

--[[
Formats any error messages generated for display
]]
function errorPrinter(errors)
	local result = ""
	for i,v in ipairs(errors) do
		local errorHTML = '<strong class="error">Coordinates: ' .. v[2] .. '</strong>'
		result = result .. errorHTML .. "<br />"
	end
	return result
end

--[[
Determine the required CSS class to display coordinates

Usually geo-nondefault is hidden by CSS, unless a user has overridden this for himself
default is the mode as specificied by the user when calling the {{coord}} template
mode is the display mode (dec or dms) that we will need to determine the css class for 
]]
function displayDefault(default, mode)
	if default == "" then
		default = "dec"
	end
	
	if default == mode then
		return "geo-default"
	else
		return "geo-nondefault"
	end
end

--[[ 
Check the input arguments for coord to determine the kind of data being provided
and then make the necessary processing.
]]
function formatTest(args)
	local result, errors;
	local primary = false;
	
	if args[1] == "" then
		-- no lat logic
		return errorPrinter( {{"formatTest", "Missing latitude"}} )
	elseif args[4] == "" and args[5] == "" and args[6] == "" then
		-- dec logic
		result, errors = parseDec( args[1], args[2], args['format'] )
		if result == nil then
			return errorPrinter( errors );
		end			  
		result.param	= table.concat( {args[1], "_N_", args[2], "_E_", args[3] } );
	elseif dmsTest(args[4], args[8]) then
		-- dms logic
		result, errors = parseDMS( args[1], args[2], args[3], args[4], 
			args[5], args[6], args[7], args[8], args['format'] )
		result.param = table.concat( { args[1], args[2], args[3], args[4], args[5],
			args[6], args[7], args[8], args[9] } , '_' );
		if args[10] ~= '' then
			table.insert( errors, { 'formatTest', 'Extra unexpected parameters' } );
		end		
	elseif dmsTest(args[3], args[6]) then
		-- dm logic
		result, errors = parseDMS( args[1], args[2], nil, args[3], 
			args[4], args[5], nil, args[6], args['format'] )
		result.param = table.concat( { args[1], args[2], args[3], args[4], args[5],
			args[6], args[7] } , '_' );
		if args[8] ~= '' then
			table.insert( errors, { 'formatTest', 'Extra unexpected parameters' } );
		end		
	elseif dmsTest(args[2], args[4]) then
		-- d logic
		result, errors = parseDMS( args[1], nil, nil, args[2], 
			args[3], nil, nil, args[4], args['format'] )
		result.param = table.concat( { args[1], args[2], args[3], args[4], args[5] } , '_' );
		if args[6] ~= '' then
			table.insert( errors, { 'formatTest', 'Extra unexpected parameters' } );
		end		
	else
		-- Error
		return errorPrinter( {{"formatTest", "Unknown argument format"}} )
	end
	result.name	 = args["name"]
	
	local extra_param = {'dim', 'globe', 'scale', 'region', 'source', 'type'}
	for _, v in ipairs( extra_param ) do
		if (args[v] or '') ~= '' then 
			table.insert( errors, {'formatTest', 'Parameter: "' .. v .. '=" should be "' .. v .. ':"' } );
		end
	end
	
	if #errors == 0 then
		return specPrinter( args, result )	
	else
		return specPrinter( args, result ) .. " " .. errorPrinter(errors) .. '[[Category:Pages with malformed coordinate tags]]'; 
	end	
end

--[[ 
Helper function, convert decimal latitude or longitude to 
degrees, minutes, and seconds format based on the specified precision.  
]]
function convert_dec2dms(coordinate, firstPostfix, secondPostfix, precision)
	local coord = tonumber(coordinate) or 0
	local postfix
	if coord >= 0 then
		postfix = firstPostfix
	else
		postfix = secondPostfix
	end

	precision = precision:lower();
	if precision == "dms" then
		return convert_dec2dms_dms( math.abs( coord ) ) .. postfix;
	elseif precision == "dm" then
		return convert_dec2dms_dm( math.abs( coord ) ) .. postfix;
	elseif precision == "d" then
		return convert_dec2dms_d( math.abs( coord ) ) .. postfix;
	end
end

--[[ Helper function, convert decimal to degrees ]]
function convert_dec2dms_d(coordinate)
	local d = math_mod._round( coordinate, 0 ) .. "°"
	return d .. ""
end

--[[ Helper function, convert decimal to degrees and minutes ]]
function convert_dec2dms_dm(coordinate)	
	coordinate = math_mod._round( coordinate * 60, 0 );
	local m = coordinate % 60;
	coordinate = math.floor( (coordinate - m) / 60 );
	local d = coordinate % 360 .."°"
	
	return d .. string.format( "%02d′", m )
end

--[[ Helper function, convert decimal to degrees, minutes, and seconds ]]
function convert_dec2dms_dms(coordinate)
	coordinate = math_mod._round( coordinate * 60 * 60, 0 );
	local s = coordinate % 60
	coordinate = math.floor( (coordinate - s) / 60 );
	local m = coordinate % 60
	coordinate = math.floor( (coordinate - m) / 60 );
	local d = coordinate % 360 .."°"

	return d .. string.format( "%02d′", m ) .. string.format( "%02d″", s )
end

--[[
Convert DMS format into a N or E decimal coordinate
]]
function convert_dms2dec(direction, degrees_str, minutes_str, seconds_str)
	local degrees = tonumber(degrees_str) or 0
	local minutes = tonumber(minutes_str) or 0
	local seconds = tonumber(seconds_str) or 0
	
	local factor = 1
	direction = mw.ustring.gsub(direction, '^[ ]*(.-)[ ]*$', '%1');
	if direction == "S" or direction == "W" then
		factor = -1
	end
	
	local precision = 0
	if seconds_str ~= nil and seconds_str ~= '' then
		precision = 5 + math.max( math_mod._precision(seconds_str), 0 );
	elseif minutes_str ~= nil and minutes_str ~= '' then
		precision = 3 + math.max( math_mod._precision(minutes_str), 0 );
	else
		precision = math.max( math_mod._precision(degrees_str), 0 );
	end
	
	local decimal = factor * (degrees+(minutes+seconds/60)/60) 
	return string.format( "%." .. precision .. "f", decimal ) -- not tonumber since this whole thing is string based.
end

--[[ 
Checks input values to for out of range errors.
]]
function validate( lat_d, lat_m, lat_s, long_d, long_m, long_s, source, strong )
	local errors = {};
	lat_d = tonumber( lat_d ) or 0;
	lat_m = tonumber( lat_m ) or 0;
	lat_s = tonumber( lat_s ) or 0;
	long_d = tonumber( long_d ) or 0;
	long_m = tonumber( long_m ) or 0;
	long_s = tonumber( long_s ) or 0;

	if strong then
		if lat_d < 0 then
			table.insert(errors, {source, "latitude degrees < 0 with hemisphere flag"})
		end
		if long_d < 0 then
			table.insert(errors, {source, "longitude degrees < 0 with hemisphere flag"})
		end
		--[[ 
		#coordinates is inconsistent about whether this is an error.  If globe: is
		specified, it won't error on this condition, but otherwise it will.
		
		For not simply disable this check.
		
		if long_d > 180 then
			table.insert(errors, {source, "longitude degrees > 180 with hemisphere flag"})
		end
		]]
	end	
		
	if lat_d > 90 then
		table.insert(errors, {source, "latitude degrees > 90"})
	end
	if lat_d < -90 then
		table.insert(errors, {source, "latitude degrees < -90"})
	end
	if lat_m >= 60 then
		table.insert(errors, {source, "latitude minutes >= 60"})
	end
	if lat_m < 0 then
		table.insert(errors, {source, "latitude minutes < 0"})
	end
	if lat_s >= 60 then
		table.insert(errors, {source, "latitude seconds >= 60"})
	end
	if lat_s < 0 then
		table.insert(errors, {source, "latitude seconds < 0"})
	end
	if long_d >= 360 then
		table.insert(errors, {source, "longitude degrees >= 360"})
	end
	if long_d <= -360 then
		table.insert(errors, {source, "longitude degrees <= -360"})
	end
	if long_m >= 60 then
		table.insert(errors, {source, "longitude minutes >= 60"})
	end
	if long_m < 0 then
		table.insert(errors, {source, "longitude minutes < 0"})
	end
	if long_s >= 60 then
		table.insert(errors, {source, "longitude seconds >= 60"})
	end
	if long_s < 0 then
		table.insert(errors, {source, "longitude seconds < 0"})
	end
	
	return errors;
end

--[[
link

Simple function to export the coordinates link for other uses.

Usage:
	{{ Invoke:Coordinates | link }}
	
]]
function coordinates.link(frame)
	return coord_link;
end

--[[
dec2dms

Wrapper to allow templates to call dec2dms directly.

Usage:
	{{ Invoke:Coordinates | dec2dms | decimal_coordinate | positive_suffix | 
		negative_suffix | precision }}
	
decimal_coordinate is converted to DMS format.  If positive, the positive_suffix
is appended (typical N or E), if negative, the negative suffix is appended.  The
specified precision is one of 'D', 'DM', or 'DMS' to specify the level of detail
to use.
]]
function coordinates.dec2dms(frame)
	globalFrame = frame
	local coordinate = frame.args[1]
	local firstPostfix = frame.args[2]
	local secondPostfix = frame.args[3]
	local precision = frame.args[4]

	return convert_dec2dms(coordinate, firstPostfix, secondPostfix, precision)
end

--[[
Helper function to determine whether to use D, DM, or DMS
format depending on the precision of the decimal input.
]]
function coordinates.determineMode( value1, value2 )
	local precision = math.max( math_mod._precision( value1 ), math_mod._precision( value2 ) );
	if precision <= 0 then
		return 'd'
	elseif precision <= 2 then
		return 'dm';
	else
		return 'dms';
	end
end		

--[[
dms2dec

Wrapper to allow templates to call dms2dec directly.

Usage:
	{{ Invoke:Coordinates | dms2dec | direction_flag | degrees | 
		minutes | seconds }}
	
Converts DMS values specified as degrees, minutes, seconds too decimal format.
direction_flag is one of N, S, E, W, and determines whether the output is 
positive (i.e. N and E) or negative (i.e. S and W).
]]
function coordinates.dms2dec(frame)
	globalFrame = frame
	local direction = frame.args[1]
	local degrees = frame.args[2]
	local minutes = frame.args[3]
	local seconds = frame.args[4]

	return convert_dms2dec(direction, degrees, minutes, seconds)
end

--[[
coord

Main entry point for Lua function to replace {{coord}}

Usage:
	{{ Invoke:Coordinates | coord }}
	{{ Invoke:Coordinates | coord | lat | long }}
	{{ Invoke:Coordinates | coord | lat | lat_flag | long | long_flag }}
	...
	
	Refer to {{coord}} documentation page for many additional parameters and 
	configuration options.
	
Note: This function provides the visual display elements of {{coord}}.  In
order to load coordinates into the database, the {{#coordinates:}} parser 
function must also be called, this is done automatically in the Lua
version of {{coord}}.
]]
function coordinates.coord(frame)
	globalFrame = frame
	local args = frame.args
	if args[1] == nil then
		local pFrame = frame:getParent();
		args = pFrame.args;
		for k,v in pairs( frame.args ) do
			args[k] = v;
		end
	end
	
	for i=1,10 do 
		if args[i] == nil then 
			args[i] = ""
		else
			args[i] = args[i]:match( '^%s*(.-)%s*$' );  --remove whitespace
		end		
	end
	args['format'] = args['format'] or '';
	
	local contents = formatTest(args)
	local Notes = args.notes or ""
	local Display = string.lower(args.display or "inline")
	if Display == '' then
		Display = 'inline';
	end
	
	local text = ''
	if string.find( Display, 'inline' ) ~= nil
		or Display == 'i'
		or Display == 'it'
		or Display == 'ti'
	then
		-- Coordinates are displayed inline.
		text = displayinline(contents, Notes)
	end
	if string.find( Display, 'title' ) ~= nil
		or Display == 't' 
		or Display == 'it'
		or Display == 'ti'
	then
		-- Coordinates are displayed in the title.
		text = text .. displaytitle(contents, Notes)
		-- Add a Wikidata category for mainspace pages.
		if mw.wikibase and current_page.namespace == 0 then
			local wikidata_cat
			local entity = mw.wikibase.getEntity()
			if entity and entity.claims and entity.claims.p625 then
				local snaktype = entity.claims.p625[0].mainsnak.snaktype
				if snaktype == 'value' then
					wikidata_cat = '[[Category:Coordinates on Wikidata]]' -- coordinates exist both here and on Wikidata, and can be compared
				elseif snaktype == 'somevalue' then
					wikidata_cat = '[[Category:Coordinates on Wikidata set to unknown value]]'
				elseif snaktype == 'novalue' then
					wikidata_cat = '[[Category:Coordinates on Wikidata set to no value]]'
				end
			else
				wikidata_cat = '[[Category:Coordinates not on Wikidata]]' -- we have to either import the coordinates to Wikidata or remove them here
			end
			if wikidata_cat then
				text = text .. wikidata_cat
			end
		end
	end

	return text
end

return coordinates