-- UnitTester provides unit testing for other Lua scripts. For details see [[Wikipedia:Lua#Unit_testing]].

-- For user documentation see talk page.

local UnitTester = {}



local frame, tick, cross, should_highlight

local result_table_header = "{|class=\"wikitable unit-tests-result\"\n|+ %s\n! !! Text !! Expected !! Actual"

local result_table_live_sandbox_header = "{|class=\"wikitable unit-tests-result\"\n|+ %s\n! !! Test !! Live !! Sandbox !! Expected"



local result_table = { n = 0 }

local result_table_mt = {

	insert = function (self, ...)

		local n = self.n

		for i = 1, select('#', ...) do

			local val = select(i, ...)

			if val ~= nil then

				n = n + 1

				selfn = val

			end

		end

		self.n = n

	end,

	insert_format = function (self, ...)

		self:insert(string.format(...))

	end,

	concat = table.concat

}

result_table_mt.__index = result_table_mt

setmetatable(result_table, result_table_mt)



local num_failures = 0

local num_runs = 0



local function first_difference(s1, s2)

	s1, s2 = tostring(s1), tostring(s2)

    if s1 == s2 then return '' end

    local max = math.min(#s1, #s2)

    for i = 1, max do

        if s1:sub(i,i) ~= s2:sub(i,i) then return i end

    end

    return max + 1

end



local function return_varargs(...)

	return ...

end



function UnitTester:calculate_output(text, expected, actual, options)

	-- Set up some variables for throughout for ease

	num_runs = num_runs + 1

	local options = options or {}

	

	-- Fix any stripmarkers if asked to do so to prevent incorrect fails

	local compared_expected = expected

	local compared_actual = actual

	if options.templatestyles then

		local pattern = '(\127[^\127]*UNIQ%-%-templatestyles%-)(%x+)(%-QINU[^\127]*\127)'

		local _, expected_stripmarker_id = compared_expected:match(pattern)				-- when module rendering has templatestyles strip markers, use ID from expected to prevent false test fail

		if expected_stripmarker_id then

			compared_actual = compared_actual:gsub(pattern, '%1' .. expected_stripmarker_id .. '%3')	-- replace actual id with expected id; ignore second capture in pattern

			compared_expected = compared_expected:gsub(pattern, '%1' .. expected_stripmarker_id .. '%3')		-- account for other strip markers

		end

	end

	if options.stripmarker then

		local pattern = '(\127[^\127]*UNIQ%-%-%l+%-)(%x+)(%-%-?QINU[^\127]*\127)'

		local _, expected_stripmarker_id = compared_expected:match(pattern)

		if expected_stripmarker_id then

			compared_actual = compared_actual:gsub(pattern, '%1' .. expected_stripmarker_id .. '%3')

			compared_expected = compared_expected:gsub(pattern, '%1' .. expected_stripmarker_id .. '%3')

		end

	end

	

	-- Perform the comparison

	local success = compared_actual == compared_expected

	if not success then

		num_failures = num_failures + 1

	end

	

	-- Sort the wikitext for displaying the results

	if options.combined then

		-- We need 2 rows available for the expected and actual columns

		-- Top one is parsed, bottom is unparsed

		local differs_at = self.differs_at and (' \n| rowspan=2|' .. first_difference(compared_expected, compared_actual)) or ''

		-- Local copies of tick/cross to allow for highlighting

		local highlight = (should_highlight and not success and 'style="background:#fc0;" ') or ''

		result_table:insert(													-- Start output

			'| ', highlight, 'rowspan=2|', success and tick or cross,			-- Tick/Cross (2 rows)

			' \n| rowspan=2|', mw.text.nowiki(text), ' \n| ',					-- Text used for the test (2 rows)

			expected, ' \n| ', actual,											-- The parsed outputs (in the 1st row)

			differs_at, ' \n|-\n| ',											-- Where any relevant difference was (2 rows)

			mw.text.nowiki(expected), ' \n| ', mw.text.nowiki(actual),			-- The unparsed outputs (in the 2nd row)

			'\n|-\n'															-- End output

		)

	else

		-- Display normally with whichever option was preferred (nowiki/parsed)

		local differs_at = self.differs_at and (' \n| ' .. first_difference(compared_expected, compared_actual)) or ''

		local formatting = options.nowiki and mw.text.nowiki or return_varargs

		local highlight = (should_highlight and not success and 'style="background:#fc0;"|') or ''

		result_table:insert(													-- Start output

			'| ', highlight, success and tick or cross,							-- Tick/Cross

			' \n| ', mw.text.nowiki(text), ' \n| ',								-- Text used for the test

			formatting(expected), ' \n| ', formatting(actual),					-- The formatted outputs

			differs_at,															-- Where any relevant difference was

			'\n|-\n'															-- End output

		)

	end

end



function UnitTester:preprocess_equals(text, expected, options)

    local actual = frame:preprocess(text)

    self:calculate_output(text, expected, actual, options)

end



function UnitTester:preprocess_equals_many(prefix, suffix, cases, options)

    for _, case in ipairs(cases) do

        self:preprocess_equals(prefix .. case1 .. suffix, case2], options)

    end

end



function UnitTester:preprocess_equals_preprocess(text1, text2, options)

	local actual = frame:preprocess(text1)

	local expected = frame:preprocess(text2)

	self:calculate_output(text1, expected, actual, options)

end



function UnitTester:preprocess_equals_compare(live, sandbox, expected, options)

	local live_text = frame:preprocess(live)

	local sandbox_text = frame:preprocess(sandbox)

	local highlight_live = false

	local highlight_sandbox = false

	num_runs = num_runs + 1

	if live_text == expected and sandbox_text == expected then

		result_table:insert('| ', tick)

	else

		result_table:insert('| ', cross)

		num_failures = num_failures + 1



		if live_text ~= expected then

			highlight_live = true

		end



		if sandbox_text ~= expected then

			highlight_sandbox = true

		end

	end

    local formatting = (options and options.nowiki and mw.text.nowiki) or return_varargs

    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, live_text) or first_difference(expected, sandbox_text)) or ''

    result_table:insert(

			' \n| ',

			mw.text.nowiki(live),

			should_highlight and highlight_live and ' \n|style="background: #fc0;"| ' or ' \n| ',

			formatting(live_text),

			should_highlight and highlight_sandbox and ' \n|style="background: #fc0;"| ' or ' \n| ',

			formatting(sandbox_text),

			' \n| ',

			formatting(expected),

			differs_at,

			"\n|-\n"

	)

end



function UnitTester:preprocess_equals_preprocess_many(prefix1, suffix1, prefix2, suffix2, cases, options)

    for _, case in ipairs(cases) do

        self:preprocess_equals_preprocess(prefix1 .. case1 .. suffix1, prefix2 .. (case2 and case2 or case1]) .. suffix2, options)

    end

end



function UnitTester:preprocess_equals_sandbox_many(module, function_name, cases, options)

    for _, case in ipairs(cases) do

		local live = module .. "|" .. function_name .. "|" .. case1 .. "}}"

		local sandbox = module .. "/sandbox|" .. function_name .. "|" .. case1 .. "}}"

        self:preprocess_equals_compare(live, sandbox, case2], options)

    end

end



function UnitTester:equals(name, actual, expected, options)

	num_runs = num_runs + 1

    if actual == expected then

        result_table:insert('| ', tick)

    else

        result_table:insert('| ', cross)

        num_failures = num_failures + 1

    end

    local formatting = (options and options.nowiki and mw.text.nowiki) or return_varargs

    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected, actual)) or ''

    local display = options and options.display or return_varargs

    result_table:insert(' \n| ', name, ' \n| ',

    	formatting(tostring(display(expected))), ' \n| ',

    	formatting(tostring(display(actual))), differs_at, "\n|-\n")

end



local function deep_compare(t1, t2, ignore_mt)

    local ty1 = type(t1)

    local ty2 = type(t2)

    if ty1 ~= ty2 then return false end

    if ty1 ~= 'table' and ty2 ~= 'table' then return t1 == t2 end



    local mt = getmetatable(t1)

    if not ignore_mt and mt and mt.__eq then return t1 == t2 end



    for k1, v1 in pairs(t1) do

        local v2 = t2k1

        if v2 == nil or not deep_compare(v1, v2) then return false end

    end

    for k2, v2 in pairs(t2) do

        local v1 = t1k2

        if v1 == nil or not deep_compare(v1, v2) then return false end

    end



    return true

end



local function val_to_str(obj)

    local function table_key_to_str(k)

        if type(k) == 'string' and mw.ustring.match(k, '^[_%a][_%a%d]*$') then

            return k

        else

            return '[' .. val_to_str(k) .. ']'

        end

    end



    if type(obj) == "string" then

        obj = mw.ustring.gsub(obj, "\n", "\\n")

        if mw.ustring.match(mw.ustring.gsub(obj, '[^\'"]', ''), '^"+$') then

            return "'" .. obj .. "'"

        end

        return '"' .. mw.ustring.gsub(obj, '"', '\\"' ) .. '"'



    elseif type(obj) == "table" then

        local result, checked = {}, {}

        for k, v in ipairs(obj) do

            table.insert(result, val_to_str(v))

            checkedk = true

        end

        for k, v in pairs(obj) do

            if not checkedk then

                table.insert(result, table_key_to_str(k) .. '=' .. val_to_str(v))

            end

        end

        return '{' .. table.concat(result, ',') .. '}'



    else

        return tostring(obj)

    end

end



function UnitTester:equals_deep(name, actual, expected, options)

	num_runs = num_runs + 1

    if deep_compare(actual, expected) then

        result_table:insert('| ', tick)

    else

        result_table:insert('| ', cross)

        num_failures = num_failures + 1

    end

    local formatting = (options and options.nowiki and mw.text.nowiki) or return_varargs

    local actual_str = val_to_str(actual)

    local expected_str = val_to_str(expected)

    local differs_at = self.differs_at and (' \n| ' .. first_difference(expected_str, actual_str)) or ''

    result_table:insert(' \n| ', name, ' \n| ', formatting(expected_str),

    	' \n| ', formatting(actual_str), differs_at, "\n|-\n")

end



function UnitTester:iterate(examples, func)

	require 'libraryUtil'.checkType('iterate', 1, examples, 'table')

	if type(func) == 'string' then

		func = selffunc

	elseif type(func) ~= 'function' then

		error(("bad argument #2 to 'iterate' (expected function or string, got %s)")

			:format(type(func)), 2)

	end



	for i, example in ipairs(examples) do

		if type(example) == 'table' then

			func(self, unpack(example))

		elseif type(example) == 'string' then

			self:heading(example)

		else

			error(('bad example #%d (expected table, got %s)')

				:format(i, type(example)), 2)

		end

	end

end



function UnitTester:heading(text)

	result_table:insert_format(' ! colspan="%u" style="text-align: left" | %s \n |- \n ',

		self.columns, text)

end



function UnitTester:run(frame_arg)

    frame = frame_arg

    self.frame = frame

    self.differs_at = frame.args'differs_at'

    tick = frame:preprocess('{{Tick}}')

    cross = frame:preprocess('{{Cross}}')



	local table_header = result_table_header

	if frame.args'live_sandbox' then

		table_header = result_table_live_sandbox_header

	end

	if frame.args.highlight then

		should_highlight = true

	end



	self.columns = 4

    if self.differs_at then

        table_header = table_header .. ' !! Differs at'

        self.columns = self.columns + 1

    end



    -- Sort results into alphabetical order.

    local self_sorted = {}

    for key, _ in pairs(self) do

        if key:find('^test') then

            table.insert(self_sorted, key)

        end

    end

    table.sort(self_sorted)

    -- Add results to the results table.

    for _, value in ipairs(self_sorted) do

        result_table:insert_format(table_header .. "\n|-\n", value)

        selfvalue](self)

        result_table:insert("|}\n")

    end



    return (num_runs == 0 and "<b>No tests were run.</b>"

    	or num_failures == 0 and "<b style=\"color:#008000\">All " .. num_runs .. " tests passed.</b>"

    	or "<b style=\"color:#800000\">" .. num_failures .. " of " .. num_runs .. " tests failed.</b>[[Category:Failed Lua testcases using Module:UnitTests]]"

    ) .. "\n\n" .. frame:preprocess(result_table:concat())

end



function UnitTester:new()

    local o = {}

    setmetatable(o, self)

    self.__index = self

    return o

end



local p = UnitTester:new()

function p.run_tests(frame) return p:run(frame) end

return p