local testing = require('testing_util')
local core = require('openmw.core')
local async = require('openmw.async')
local util = require('openmw.util')
local types = require('openmw.types')
local world = require('openmw.world')

local function testTimers()
    testing.expectAlmostEqual(core.getGameTimeScale(), 30, 'incorrect getGameTimeScale() result')
    testing.expectAlmostEqual(core.getSimulationTimeScale(), 1, 'incorrect getSimulationTimeScale result')

    local startGameTime = core.getGameTime()
    local startSimulationTime = core.getSimulationTime()

    local ts1, ts2, th1, th2
    local cb = async:registerTimerCallback("tfunc", function(arg)
        if arg == 'g' then
            th1 = core.getGameTime() - startGameTime
        else
            ts1 = core.getSimulationTime() - startSimulationTime
        end
    end)
    async:newGameTimer(36, cb, 'g')
    async:newSimulationTimer(0.5, cb, 's')
    async:newUnsavableGameTimer(72, function()
        th2 = core.getGameTime() - startGameTime
    end)
    async:newUnsavableSimulationTimer(1, function()
        ts2 = core.getSimulationTime() - startSimulationTime
    end)

    while not (ts1 and ts2 and th1 and th2) do
        coroutine.yield()
    end

    testing.expectGreaterOrEqual(th1, 36, 'async:newGameTimer failed')
    testing.expectGreaterOrEqual(ts1, 0.5, 'async:newSimulationTimer failed')
    testing.expectGreaterOrEqual(th2, 72, 'async:newUnsavableGameTimer failed')
    testing.expectGreaterOrEqual(ts2, 1, 'async:newUnsavableSimulationTimer failed')
end

local function testTeleport()
    player:teleport('', util.vector3(100, 50, 500), util.transform.rotateZ(math.rad(90)))
    coroutine.yield()
    testing.expect(player.cell.isExterior, 'teleport to exterior failed')
    testing.expectEqualWithDelta(player.position.x, 100, 1, 'incorrect position after teleporting')
    testing.expectEqualWithDelta(player.position.y, 50, 1, 'incorrect position after teleporting')
    testing.expectEqualWithDelta(player.position.z, 500, 1, 'incorrect position after teleporting')
    testing.expectEqualWithDelta(player.rotation:getYaw(), math.rad(90), 0.05, 'incorrect yaw rotation after teleporting')
    testing.expectEqualWithDelta(player.rotation:getPitch(), math.rad(0), 0.05, 'incorrect pitch rotation after teleporting')

    local rotationX1, rotationZ1 = player.rotation:getAnglesXZ()
    testing.expectEqualWithDelta(rotationX1, math.rad(0), 0.05, 'incorrect x rotation from getAnglesXZ after teleporting')
    testing.expectEqualWithDelta(rotationZ1, math.rad(90), 0.05, 'incorrect z rotation from getAnglesXZ after teleporting')

    local rotationZ2, rotationY2, rotationX2 = player.rotation:getAnglesZYX()
    testing.expectEqualWithDelta(rotationZ2, math.rad(90), 0.05, 'incorrect z rotation from getAnglesZYX after teleporting')
    testing.expectEqualWithDelta(rotationY2, math.rad(0), 0.05, 'incorrect y rotation from getAnglesZYX after teleporting')
    testing.expectEqualWithDelta(rotationX2, math.rad(0), 0.05, 'incorrect x rotation from getAnglesZYX after teleporting')

    player:teleport('', player.position, {rotation=util.transform.rotateZ(math.rad(-90)), onGround=true})
    coroutine.yield()
    testing.expectEqualWithDelta(player.rotation:getYaw(), math.rad(-90), 0.05, 'options.rotation is not working')
    testing.expectLessOrEqual(player.position.z, 400, 'options.onGround is not working')

    player:teleport('', util.vector3(50, -100, 0))
    coroutine.yield()
    testing.expect(player.cell.isExterior, 'teleport to exterior failed')
    testing.expectEqualWithDelta(player.position.x, 50, 1, 'incorrect position after teleporting')
    testing.expectEqualWithDelta(player.position.y, -100, 1, 'incorrect position after teleporting')
    testing.expectEqualWithDelta(player.rotation:getYaw(), math.rad(-90), 0.05, 'teleporting changes rotation')
end

local function testGetGMST()
    testing.expectEqual(core.getGMST('non-existed gmst'), nil)
    testing.expectEqual(core.getGMST('Water_RippleFrameCount'), 4)
    testing.expectEqual(core.getGMST('Inventory_DirectionalDiffuseR'), 0.5)
    testing.expectEqual(core.getGMST('Level_Up_Level2'), 'something')
end

local function testMWScript()
    local variableStoreCount = 18
    local variableStore = world.mwscript.getGlobalVariables(player)
    testing.expectEqual(variableStoreCount, #variableStore)
    
    variableStore.year = 5
    testing.expectEqual(5, variableStore.year)
    variableStore.year = 1
    local indexCheck = 0
    for index, value in ipairs(variableStore) do
        testing.expectEqual(variableStore[index], value)
        indexCheck = indexCheck + 1
    end
    testing.expectEqual(variableStoreCount, indexCheck)
    indexCheck = 0
    for index, value in pairs(variableStore) do
        testing.expectEqual(variableStore[index], value)
        indexCheck = indexCheck + 1
    end
    testing.expectEqual(variableStoreCount, indexCheck)
end

local function testRecordStore(store, storeName, skipPairs)
    testing.expect(store.records)
    local firstRecord = store.records[1]
    if not firstRecord then
        return
    end
    testing.expectEqual(firstRecord.id, store.records[firstRecord.id].id)
    local status, _ = pcall(function()
        for index, value in ipairs(store.records) do
            if value.id == firstRecord.id then
                testing.expectEqual(index, 1, storeName)
                break
            end
        end
    end)

    testing.expectEqual(status, true, storeName)
    
end

local function testRecordStores()
    for key, type in pairs(types) do
        if type.records then
            testRecordStore(type, key)
        end
    end
    testRecordStore(core.magic.enchantments, "enchantments")
    testRecordStore(core.magic.effects, "effects", true)
    testRecordStore(core.magic.spells, "spells")

    testRecordStore(core.stats.Attribute, "Attribute")
    testRecordStore(core.stats.Skill, "Skill")

    testRecordStore(core.sound, "sound")
    testRecordStore(core.factions, "factions")

    testRecordStore(types.NPC.classes, "classes")
    testRecordStore(types.NPC.races, "races")
    testRecordStore(types.Player.birthSigns, "birthSigns")
end

local function testRecordCreation()
    local newLight = {
        isCarriable = true,
        isDynamic = true,
        isFire =false,
        isFlicker = false,
        isFlickerSlow = false,
        isNegative = false,
        isOffByDefault = false,
        isPulse = false,
        weight = 1,
        value = 10,
        duration = 12,
        radius = 30,
        color = 5,
        name = "TestLight",
        model = "meshes\\marker_door.dae"
    }
    local draft = types.Light.createRecordDraft(newLight)
    local record = world.createRecord(draft)
    for key, value in pairs(newLight) do
        testing.expectEqual(record[key], value)
    end
end

local function testUTF8Chars()
    testing.expectEqual(utf8.codepoint("😀"), 0x1F600)

    local chars = {}

    for codepoint = 0, 0x10FFFF do
        local char = utf8.char(codepoint)
        local charSize = string.len(char)

        testing.expect(not chars[char], nil, "Duplicate UTF-8 character: " .. char)
        chars[char] = true

        if codepoint <= 0x7F then
            testing.expectEqual(charSize, 1)
        elseif codepoint <= 0x7FF then
            testing.expectEqual(charSize, 2)
        elseif codepoint <= 0xFFFF then
            testing.expectEqual(charSize, 3)
        elseif codepoint <= 0x10FFFF then
            testing.expectEqual(charSize, 4)
        end

        testing.expectEqual(utf8.codepoint(char), codepoint)
        testing.expectEqual(utf8.len(char), 1)
    end
end

local function testUTF8Strings()
    local utf8str = "Hello, 你好, 🌎!"

    local str = ""
    for utf_char in utf8str:gmatch(utf8.charpattern) do
        str = str .. utf_char
    end
    testing.expectEqual(str, utf8str)

    testing.expectEqual(utf8.len(utf8str), 13)
    testing.expectEqual(utf8.offset(utf8str, 9), 11)
end

local function testMemoryLimit()
    local ok, err = pcall(function()
        local t = {}
        local n = 1
        while true do
            t[n] = n
            n = n + 1
        end
    end)
    testing.expectEqual(ok, false, 'Script reaching memory limit should fail')
    testing.expectEqual(err, 'not enough memory')
end

local function initPlayer()
    player:teleport('', util.vector3(4096, 4096, 1745), util.transform.identity)
    coroutine.yield()
end

tests = {
    {'timers', testTimers},
    {'rotating player with controls.yawChange should change rotation', function()
        initPlayer()
        testing.runLocalTest(player, 'playerYawRotation')
    end},
    {'rotating player with controls.pitchChange should change rotation', function()
        initPlayer()
        testing.runLocalTest(player, 'playerPitchRotation')
    end},
    {'rotating player with controls.pitchChange and controls.yawChange should change rotation', function()
        initPlayer()
        testing.runLocalTest(player, 'playerPitchAndYawRotation')
    end},
    {'rotating player should not lead to nan rotation', function()
        initPlayer()
        testing.runLocalTest(player, 'playerRotation')
    end},
    {'playerForwardRunning', function()
        initPlayer()
        testing.runLocalTest(player, 'playerForwardRunning')
    end},
    {'playerDiagonalWalking', function()
        initPlayer()
        testing.runLocalTest(player, 'playerDiagonalWalking')
    end},
    {'findPath', function()
        initPlayer()
        testing.runLocalTest(player, 'findPath')
    end},
    {'findRandomPointAroundCircle', function()
        initPlayer()
        testing.runLocalTest(player, 'findRandomPointAroundCircle')
    end},
    {'castNavigationRay', function()
        initPlayer()
        testing.runLocalTest(player, 'castNavigationRay')
    end},
    {'findNearestNavMeshPosition', function()
        initPlayer()
        testing.runLocalTest(player, 'findNearestNavMeshPosition')
    end},
    {'teleport', testTeleport},
    {'getGMST', testGetGMST},
    {'recordStores', testRecordStores},
    {'recordCreation', testRecordCreation},
    {'utf8Chars', testUTF8Chars},
    {'utf8Strings', testUTF8Strings},
    {'mwscript', testMWScript},
    {'testMemoryLimit', testMemoryLimit},
    {'playerMemoryLimit', function()
        initPlayer()
        testing.runLocalTest(player, 'playerMemoryLimit')
    end}
}

return {
    engineHandlers = {
        onUpdate = testing.testRunner(tests),
        onPlayerAdded = function(p) player = p end,
    },
    eventHandlers = testing.eventHandlers,
}