--------------------------------------------------------------------------------
-- Lua 5.2 compat

if not setfenv then -- Lua 5.2
  -- based on http://lua-users.org/lists/lua-l/2010-06/msg00314.html
  -- this assumes f is a function
  local function findenv(f)
    local level = 1
    repeat
      local name, value = debug.getupvalue(f, level)
      if name == '_ENV' then return level, value end
      level = level + 1
    until name == nil
    return nil end
  getfenv = function (f) return(select(2, findenv(f)) or _G) end
  setfenv = function (f, t)
    local level = findenv(f)
    if level then debug.setupvalue(f, level, t) end
    return f end
end

--------------------------------------------------------------------------------

local SUITE = require 'TestSuite' 'resilience'
SUITE:setEnvironment{
    pretty  = require('pretty'),
    setfenv = setfenv,
}

--------------------------------------------------------------------------------
-- Prevent usage of unknown options.

SUITE:addTest('Dont allow unknown options', function ()
    local error_msg = bad_call(pretty, 'Hello World', { some_random_option = true })
    assert(error_msg)
end)

SUITE:addTest('Dont allow bad types in options', function ()
    local error_msg = bad_call(pretty, 'Hello World', { indent = 51 })
    assert(error_msg)
end)

--------------------------------------------------------------------------------
-- Strange standard libs

SUITE:addTest('no_std_lib', function ()
    -- This tests whether one could load the library with an empty env, without
    -- an error.
    local env = {}
    local library = setfenv(loadfile('./library.lua'), env)()

    for func, func_info in pairs(library) do
        error(('For some reason %s is defined in the library'):format(func_info.name))
    end
end)

SUITE:addTest('a_very_small_part_of_math', function ()
    -- This tests whether one could load the library with an empty env, without
    -- an error.
    local env = { debug = debug, math = { abs = math.abs } }
    local library = setfenv(loadfile('./library.lua'), env)()

    assert( library[math.abs], 'Why is math.abs not defined in the library?' )
end)

SUITE:addTest('redefined part of math', function ()
    -- This tests whether the library ignores a redefined function of an
    -- builtin, when defining documentation.
    local env  =  { debug = debug, setfenv = setfenv, loadfile = function() end }
    local library = setfenv(loadfile('./library.lua'), env)()

    assert(     library[env.setfenv],  'Why is setfenv not defined in the library?' )
    assert( not library[env.loadfile], 'Why is loadfile defined in the library?' )
end)

SUITE:addTest('redefined part of math 2', function ()
    -- This tests whether the library allows a redefined function of an
    -- builtin, when defining documentation, due to not being able to determine
    -- the origin of the function.
    local env  =  { setfenv = setfenv, loadfile = function() end }
    local library = setfenv(loadfile('./library.lua'), env)()

    assert( library[env.setfenv],  'Why is setfenv not defined in the library?' )
    assert( library[env.loadfile], 'Why is loadfile not defined in the library?' )
end)

--------------------------------------------------------------------------------

if false then
    -- This test takes a long time.
    local data = {}
    for str, name in SUITE:getExamples 'STRING_UTF8_MALFORMED' do
        data[#data+1] = {str, name}
    end

    local pjk_path = '/tmp/test_pjk_'..os.time()

    local conf = [[
    function love.conf(t)

        -- Graphics Settings
        t.window.width = 1
        t.window.height = 1
        t.window.minwidth   = 1
        t.window.minheight  = 1

        -- Modules
        t.modules.audio     = false
        t.modules.event     = true
        t.modules.graphics  = true
        t.modules.image     = false
        t.modules.joystick  = false
        t.modules.keyboard  = false
        t.modules.math      = false
        t.modules.mouse     = false
        t.modules.physics   = false
        t.modules.sound     = false
        t.modules.system    = false
        t.modules.timer     = false
        t.modules.touch     = false
        t.modules.video     = false
        t.modules.window    = true
        t.modules.thread    = false
    end]]

    -- Create project, main.lua and conf.lua
    os.execute('mkdir '..pjk_path)
    local f = io.open(pjk_path..'/conf.lua', 'w')
          f:write(conf)
          f:close()
    local f = io.open(pjk_path..'/main.lua', 'w')
          f:write''
          f:close()

    SUITE:addTest('Proper malformed utf8 escaping (through LÖVE)', function (str, name)
        -- This test asserts that malformed unicode strings are escaped. This is
        -- done by checking whether LÖVE can draw the sequence of bytes, given by
        -- `pretty`. LÖVE have robust unicode checking, and will throw an error if
        -- the characters is not escaped properly.

        -- The input strings are gotten from TestSuite's example strings.

        --do return error 'Test skipped' end

        -- Create project and main.lua
        local f = io.open(pjk_path..'/main.lua', 'w')
              f:write('love.errhand = love.event.quit love.graphics.print('..pretty(str)..') love.event.quit(0)')
              f:close()

        -- Run project
        local status_code  =  os.execute('love '..pjk_path)
        if status_code ~= 0 then
            local l = {}
            for i = 1, #str do  l[i] = tostring(str:byte(i))  end
            error(('Could not escape the string "%s" properly: %s\n\tByte-sequence: \\%s'):format(name, str, table.concat(l, '\\')))
        end
    end, { data = data })
end

--------------------------------------------------------------------------------
-- Strange metatable

SUITE:addTest('Metatable: Error on operator', function (op)
    pretty( setmetatable( { a = 2, b = 4, 1, 2, 3 } , {[op] = function() error 'This should be unreachable!' end}) )
    assert(true)
end, { data = { '__add', '__sub', '__mul', '__div', '__mod', '__pow', '__unm', '__concat','__len', '__eq', '__lt', '__le', '__index', '__newindex', '__call', '__tostring' } })

SUITE:addTest('Metatable: # returns bogus length', function ()
    assert_equal('{ 1, 2, 3, 4 }', pretty( setmetatable({ 1, 2, 3, 4 }, {__len = function() return 2 end})))
end)

SUITE:addTest('Metatable: object is never equal to anything, not even itself', function ()
    assert_equal('{ 1, 2, 3, 4 }', pretty( setmetatable({ 1, 2, 3, 4 }, {__eq = function() return false end})))
end)

SUITE:addTest('Metatable: object contains nothing, but has prototype', function ()
    pretty( setmetatable({}, {__index = { a = 2, b = 5, c = 2 }}) )
    assert(true)
    -- TODO: Determine what to output do when this happens.
end)

SUITE:addTest('Metatable: object contains every odd number', function ()
    pretty( setmetatable({}, {__index = function(t, i) return i*2-1 end}) )
    assert(true)
    -- TODO: Determine what to output do when this happens.
end)

SUITE:addTest('Metatable: object is also callable', function ()
    pretty( setmetatable({}, {__call = function(t, i) return i*2-1 end}) )
    assert(true)
    -- TODO: Determine what to output do when this happens.
end)

--------------------------------------------------------------------------------
-- Metatable __tostring


do
    local data = {}
    for str, name in SUITE:getExamples 'TABLE_METAMETHODS' do
        data[#data+1] = { name, str }
    end

    SUITE:addTest('Metatable shenanigans', function (_, str)
        pretty(str)
        assert(true)
    end, { data = data })
end


-- TODO: Tests for alternative modes (__mode = 'k', __mode = 'v', __mode = 'kv')
-- TODO: Tests for __metatable

--------------------------------------------------------------------------------

return SUITE