Module:Sandbox/Sebschlicht

Documentation for this module may be created at Module:Sandbox/Sebschlicht/doc

local u = {}
local e = nil;

local function splitString(stringValue, pattern)
	local splitted = {}
	for s in stringValue:gmatch(pattern) do
		table.insert(splitted, s);
	end
	return splitted;
end

local function splitLines(stringValue)
	return splitString(stringValue, "(.-)\r?\n");
end

-- costs: 1
local function getDefaultIndex()
	local crrTitle = mw.title.getCurrentTitle();
	local rootTitle = crrTitle.rootPageTitle;
	return rootTitle.fullText .. "/MoocIndex";
end

-- costs: 2 (1 intern)
local function readIndex(indexUrl)
	local indexUrl = indexUrl or getDefaultIndex();
	local indexPage = mw.title.new(indexUrl);
	if indexPage then
		return indexPage:getContent();
	else
		error('failed to read index from "' .. indexUrl .. '"');
	end
end

local function extractFromIndex(indexPlain, itemType, itemName)
	local itemIdentifier = itemType .. "|" .. itemName;
	local textLines = splitLines(indexPlain);
	return #textLines;
end

local function loadIndex(typeIdentifier, itemName, indexUrl)
	local itemName = itemName;
	if not itemName then
		error('item name is missing');
	end
	local indexUrl = getDefaultIndex();
	
	local itemType = typeIdentifier;
	if not itemType then
		error('item type is missing');
	end
	
	local indexPlain = readIndex(indexUrl);
	if not indexPlain then
		error("index is empty @ " .. indexUrl);
	end
	
	local indexRelevant = extractFromIndex(indexPlain, itemType, itemName);
	return indexUrl;
end
 
function u.renderLesson( frame )
	local itemName = frame.args["name"];
	local itemType = frame.args["type"];
	local indexUrl = frame.args["indexUrl"];
	local isSuccess, value = pcall(loadIndex, itemType, itemName, indexUrl);
	if isSuccess then
		return value;
	else
		-- value is error message
		return 'failed to load MOOC index: ' .. value;
	end
end

return u