NSMB Objects

-- Author: Suuper
-- If you make any significant improvements, please share.

local addrPtrToFirstObjectByType = 0x208FB38
local offsetNodeByType = 0x38

-- General stuff
local typeOffset = 0x44
local XOffset = 0x60
local YOffset = 0x64
local XVelOffset = 0xD0
local YVelOffset = 0xD4
local XVelTargetOffset = 0xE0
local YVelTargetOffset = 0xE4
local scaleXOffset = 0xF0
local widthOffset = 0x13C
local heightOffset = 0x140
local someFlagsOffset = 0x146

-- Specific object types
local MarioXVelOffset = 0xB4
local MarioMaxSpeedOffset = 0xB8

function read_u32(addr)
    return memory.read_u32_le(addr)
end
function write_u32(addr, value)
    return memory.write_u32_le(addr, value, "ARM9 System Bus")
end
function read_s32(addr)
    return memory.read_s32_le(addr)
end
function write_s32(addr, value)
    return memory.write_s32_le(addr, value, "ARM9 System Bus")
end
function read_u16(addr)
    return memory.read_u16_le(addr)
end
function write_u16(addr, value)
    return memory.write_u16_le(addr, value, "ARM9 System Bus")
end
function read_u8(addr)
    return memory.read_u8(addr)
end
function write_u8(addr, value)
    memory.write_u8(addr, value, "ARM9 System Bus")
end
function read_s8(addr)
    return memory.read_s8(addr)
end
function write_s8(addr, value)
    return memory.write_s8(addr, value, "ARM9 System Bus")
end

function drawText(x, y, str)
    gui.drawText(x, y + 192, str)
end

function isTangible(objAddr)
    local flags = read_s8(objAddr + someFlagsOffset)
    return bit.check(flags, 0)
end

local objectTypes = {}
objectTypes[0x1C] = "Mario"
objectTypes[0x1F] = "Piranha Plant"
objectTypes[0x28] = "Cheep Cheep"
objectTypes[0x2B] = "Bumped Block"
objectTypes[0x2C] = "Powerup" -- Fireflower and mini are same
objectTypes[0x31] = "Flag Pole"
objectTypes[0x32] = "Spring"
objectTypes[0x35] = "Lakitu"
objectTypes[0x36] = "Spiney Beetle"
objectTypes[0x37] = "Boo"
objectTypes[0x44] = "Buzzy Beetle"
objectTypes[0x45] = "Dry Bones"
objectTypes[0x47] = "Fireball Enemy"
objectTypes[0x4C] = "Mega GP Drop"
objectTypes[0x51] = "Hammer Bro"
objectTypes[0x56] = "Shark"
objectTypes[0x5A] = "Bowser's Fireball"
objectTypes[0x5B] = "Spinny Spring"
objectTypes[0x5F] = "Red Coin"
objectTypes[0x60] = "P Switch"
objectTypes[0x62] = "Blue P Switch"
objectTypes[0x64] = "Red ! Switch"
objectTypes[0x68] = "Expandable Block"
objectTypes[0x7E] = "Swooper"
objectTypes[0x84] = "Bowser Junior"
objectTypes[0x85] = "Princess Peach"
objectTypes[0x89] = "Roulette Block"
objectTypes[0x8B] = "Basher"
objectTypes[0x8F] = "Bounce Bubble"
objectTypes[0x95] = "Bowser"
objectTypes[0x9B] = "Boss Switch"
objectTypes[0x9D] = "Respawnable Hidden Block"
objectTypes[0x9E] = "Coin"
objectTypes[0x9F] = "Star Coin"
objectTypes[0xA0] = "Goomba"
objectTypes[0xA3] = "Koopa" -- green or red
objectTypes[0xA4] = "Paratroopa"
objectTypes[0xAE] = "Giant Spike Fish"
objectTypes[0xAF] = "Red Coin Ring"
objectTypes[0xBB] = "Checkpoint"
objectTypes[0xB4] = "Snowball Thrower"
objectTypes[0xB5] = "Snowball"
objectTypes[0xC3] = "Tightrope"
objectTypes[0xC8] = "Moving Platform"
objectTypes[0xCF] = "Moving Slate?"
objectTypes[0xD2] = "See-saw"
objectTypes[0xE3] = "Chomping Piranha Plant"
objectTypes[0xE8] = "Pokey"
objectTypes[0xE9] = "Manhole"
objectTypes[0xEA] = "Bumpable Platform"
objectTypes[0xEB] = "Tilting Mushroom"
objectTypes[0xF7] = "Quicksnow"
objectTypes[0x102] = "Falling Snow"
objectTypes[0x103] = "One-Way Gate"
objectTypes[0x105] = "Red ? Block"
objectTypes[0x107] = "Boo Elevator Platform"
objectTypes[0x115] = "Broken Brick"
objectTypes[0x133] = "Temp Projectile Slot"
objectTypes[0x135] = "Water"
function getObjectTypeName(obj)
    local objType = read_u16(obj + typeOffset)
    if objectTypes[objType] ~= nil then
        return objectTypes[objType]
    else
        return "Unknown"
    end
end

local allObjects = {}
local objectsByDropDown = {}
local objectCount = 0

local spawnActivity = false

local shouldExit = false
local detailForms = {}

function GetFirstObject()
    local nodePtr = read_u32(addrPtrToFirstObjectByType)
    if nodePtr == 0 then
        return 0
    else
        --return read_u32(nodePtr + 8) -- Works, but why bother reading it?
        return nodePtr - offsetNodeByType
    end
end
function GetNextObject(obj)
    local nextNodePtr = read_u32(obj + offsetNodeByType + 4)
    if nextNodePtr == 0 then
        return 0
    else
        --return read_u32(nextNodePtr + 8)
        return nextNodePtr - offsetNodeByType
    end
end
function GetPreviousObject(obj)
    local nextNodePtr = read_u32(obj + offsetNodeByType)
    if nextNodePtr == 0 then
        return 0
    else
        return read_u32(nextNodePtr + 8)
    end
end

function hex(v, padLength)
    padLength = padLength or "1"
    return string.format("%0" .. padLength .. "x", v)
end

function formatPosition(v)
    local sign = " "
    if v < 0 then
        sign = "-"
        v = -v
    end

    local subpixel = v % 0x1000
    v = math.floor(v / 0x1000)
    local pixel = v % 0x10
    local block = math.floor(v / 0x10)

    return sign .. string.format("%04d", block) .. "|" .. string.format("%02d", pixel) .. "|" .. string.format("%04d", subpixel)
end
function formatSpeed(v)
    local sign = " "
    if v < 0 then
        sign = "-"
        v = -v
    end

    local subpixel = v % 0x1000
    local pixel = math.floor(v / 0x1000)

    return sign .. string.format("%02d", pixel) .. "|" .. string.format("%04d", subpixel)
end
function parseBarFormat(str)
    local i, _ = string.find(str, "|")
    if i == nil then
        -- floor because we might have decimal, e.g. 1.51947
        return math.floor(tonumber(str) * 0x1000)
    else
        local first = string.sub(str, 0, i - 1)
        local second = string.sub(str, i + 1, nil)
        i, _ = string.find(second, "|")
        if i == nil then
            -- pixel|subpixel
            i, _ = string.find(first, "-")
            if i == nil then
                return tonumber(first) * 0x1000 + tonumber(second)
            else
                return tonumber(first) * 0x1000 - tonumber(second)
            end
        else
            -- block|pixel|subpixel
            local third = string.sub(second, i + 1, nil)
            second = string.sub(second, 0, i - 1)
            i, _ = string.find(first, "-")
            if i == nil then
                return  tonumber(first) * 0x10000 + tonumber(second * 0x1000) + tonumber(third)
            else
                return  tonumber(first) * 0x10000 - tonumber(second * 0x1000) - tonumber(third)
            end
        end
    end
end
function formatNone(v)
    return v
end

-- Lua class for RAM Watch controls
function GetAddress(pointerList)
    local address = pointerList[1]
    for i = 2, #pointerList do
        address = read_u32(address) + pointerList[i]
    end
    return address
end

WatchControls = {}
WatchControls.x = 0
WatchControls.y = 0
WatchControls.value = 0
WatchControls.editable = true
function WatchControls:new(parentForm, x, y, width, ptr, name, readFunc, formatFunc, writeFunc, parseFunc)
    -- Validate and set variables
    if type(ptr) == "number" then
        ptr = { ptr }
    end
    if (name ~= nil) then name = name .. ":" else name = "?:" end
    if (readFunc == nil) then readFunc = read_u32 end
    if (formatFunc == nil) then readFunc = formatNone end
    if (parseFunc == nil) then parseFunc = tonumber end

    local newWatchControls = {}
    newWatchControls.form = form
    newWatchControls.ptr = ptr
    newWatchControls.name = name
    newWatchControls.readFunc = readFunc
    newWatchControls.formatFunc = formatFunc
    newWatchControls.writeFunc = writeFunc
    newWatchControls.parseFunc = parseFunc

    -- Create controls
    newWatchControls.label = forms.label(parentForm.handle, name, x, y, 0, 0, true)
    forms.setproperty(newWatchControls.label, "AutoSize", true)
    if writeFunc ~= nil then -- should be editable
        x = x + forms.getproperty(newWatchControls.label, "Width")
        newWatchControls.box = forms.textbox(parentForm.handle, "0", width, 18, nil, x, y, false, true)
    end

    setmetatable(newWatchControls, self);
    self.__index = self;
    return newWatchControls
end
function WatchControls:updateDisplay()
    local displayStr = self.formatFunc(self.readFunc(GetAddress(self.ptr)))
    if self.writeFunc == nil then
        forms.settext(self.label, self.name .. displayStr)
    else
        forms.settext(self.box, displayStr)
    end
end
function WatchControls:applyEdits()
    if self.writeFunc == nil then
        return
    end

    self.writeFunc(GetAddress(self.ptr), self.parseFunc(forms.gettext(self.box)))
end

-- Set up form
function createMainForm()
    local form = {}
    form.handle = forms.newform(210, 90, "NSMB Objects", function()
        shouldExit = true
        for k in pairs(detailForms) do
            forms.destroy(detailForms[k].handle)
        end
    end)
    forms.setDefaultTextBackground(form.handle, "Transparent")

    -- BizHawk is stupid and requires at least one element present.
    -- It also requires that all elements already be strings.
    form.objectDropDown = forms.dropdown(form.handle, {"placeholder"}, 10, 10, 180, 10)

    form.countLabel = forms.label(form.handle, "label", 10, 64)
    forms.setproperty(form.countLabel, "AutoSize", true)

    form.getDetailsButton = forms.button(form.handle, "Get Details", function()
        local index = tonumber(forms.getproperty(form.objectDropDown, "SelectedIndex"))
        if index == -1 then
            return
        end

        local df = createObjectDetailsForm(objectsByDropDown[index + 1])
        if objectsByDropDown[index + 1] == nil then
            error("obj was nil, index: " .. index)
        end
        updateDetails(df)
    end, 10, 35, 80, 24)

    return form
end
local mainForm = createMainForm()

function createObjectDetailsForm(objAddress)
    local form = {}
    form.obj = objAddress
    local listIndex = #detailForms + 1
    detailForms[#detailForms + 1] = form

    form.handle = forms.newform(300, 240, "Details for " .. getObjectTypeName(objAddress), function()
        detailForms[listIndex] = nil
    end)
    forms.setDefaultTextBackground(form.handle, "Transparent")
    form.objType = read_u16(objAddress + typeOffset)

    form.addressLabel = forms.label(form.handle, "Address: 0", 10, 10)
    forms.setproperty(form.addressLabel, "AutoSize", true)

    -- Not all objects have the same properties
    local _xVelOffset = XVelOffset
    local _xVelTargetOffset = XVelTargetOffset
    if form.objType == 0x1C then -- Mario
        _xVelOffset = MarioXVelOffset
        _xVelTargetOffset = MarioMaxSpeedOffset
    end

    local verticalSeparation = 23
    local y = 30
    form.watches = {}
    -- location
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 10, y + verticalSeparation * 0, 100,
        { form.obj + XOffset }, "X ",
        read_s32, formatPosition, write_s32, parseBarFormat
    )
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 10, y + verticalSeparation * 1, 100,
        { form.obj + YOffset }, "Y ",
        read_s32, formatPosition, write_s32, parseBarFormat
    )
    -- velocity
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 10, y + verticalSeparation * 2, 65,
        { form.obj + _xVelOffset }, "X Speed",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 10, y + verticalSeparation * 3, 65,
        { form.obj + YVelOffset }, "Y Speed",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )
    -- size
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 160, y + verticalSeparation * 0, 65,
        { form.obj + widthOffset }, "Width ",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 160, y + verticalSeparation * 1, 65,
        { form.obj + heightOffset }, "Height",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )
    -- target velocity
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 140, y + verticalSeparation * 2, 65,
        { form.obj + _xVelTargetOffset }, "-> target",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )
    form.watches[#form.watches + 1] = WatchControls:new(
        form, 140, y + verticalSeparation * 3, 65,
        { form.obj + YVelTargetOffset }, "-> target",
        read_s32, formatSpeed, write_s32, parseBarFormat
    )

    form.tangibleCheckbox = forms.checkbox(form.handle, "Tangible", 10, y + verticalSeparation * 4)

    local applyButton = forms.button(form.handle, "Apply", function()
        apply(form)
    end, 200, y + verticalSeparation * 4)

    -- collision checking
    local y = y + verticalSeparation * 5 + 10
    form.collisionSelectLabel = forms.label(form.handle, "Check collision:", 10, y + 2)
    forms.setproperty(form.collisionSelectLabel, "AutoSize", true)
    form.objectDropDown = forms.dropdown(form.handle, { "placeholder" }, 96, y, 178, 10)
    refreshObjectDropDown(form.objectDropDown, 0)

    forms.setproperty(form.objectDropDown, "SelectedIndex", -1)

    form.collisionDistanceLabel = forms.label(form.handle, "Distance to collide:", 10, y + 25)
    form.collisionDistanceHLabel = forms.label(form.handle, "0", 30, y + 40, 0, 0, true)
    form.collisionDistanceVLabel = forms.label(form.handle, "0", 30, y + 55, 0, 0, true)
    forms.setproperty(form.collisionDistanceLabel, "AutoSize", true)
    forms.setproperty(form.collisionDistanceHLabel, "AutoSize", true)
    forms.setproperty(form.collisionDistanceVLabel, "AutoSize", true)

    return form
end

function updateDetails(detailsForm)
    local obj = detailsForm.obj
    if read_u32(obj) == 0 or read_u16(obj + typeOffset) ~= detailsForm.objType then
        forms.settext(detailsForm.addressLabel, "Address: Despawned")

        for i = 1, #detailsForm.watches do
            if detailsForm.watches[i].box ~= nil then
                forms.settext(detailsForm.watches[i].box, "Despawned")
            else
                forms.settext(detailsForm.watches[i].label, "Despawned")
            end
        end
    else
        forms.settext(detailsForm.addressLabel, "Address: 0x" .. hex(obj, 8))
        forms.setproperty(detailsForm.tangibleCheckbox, "Checked", isTangible(obj))

        for i = 1, #detailsForm.watches do
            detailsForm.watches[i]:updateDisplay()
        end

        local index = tonumber(forms.getproperty(detailsForm.objectDropDown, "SelectedIndex"))
        if spawnActivity then
            refreshObjectDropDown(detailsForm.objectDropDown, detailsForm.selectedCollisionObj)
            index = tonumber(forms.getproperty(detailsForm.objectDropDown, "SelectedIndex"))
        end
        if index ~= -1 then
            detailsForm.selectedCollisionObj = objectsByDropDown[index + 1]
            local this = {
                X = read_s32(obj + XOffset),
                Y = read_s32(obj + YOffset),
                Width = read_s32(obj + widthOffset),
                Height = read_s32(obj + heightOffset),
            }
            local otherObj = detailsForm.selectedCollisionObj
            local other = {
                X = read_s32(otherObj + XOffset),
                Y = read_s32(otherObj + YOffset),
                Width = read_s32(otherObj + widthOffset),
                Height = read_s32(otherObj + heightOffset),
            }
            local distanceRight = math.max(0, (other.X - other.Width) - (this.X + this.Width))
            local distanceLeft = math.max(0, (this.X - this.Width) - (other.X + other.Width))
            local distanceH = math.max(distanceRight, distanceLeft)
            forms.settext(detailsForm.collisionDistanceHLabel, formatPosition(distanceH))
            local distanceUp = math.max(0, (other.Y) - (this.Y + this.Height))
            local distanceDown = math.max(0, (this.Y) - (other.Y + other.Height))
            local distanceV = math.max(distanceUp, distanceDown)
            forms.settext(detailsForm.collisionDistanceVLabel, formatPosition(distanceV))
        end
    end
end

function apply(detailsForm)
    function inner()
        local obj = detailsForm.obj
        if read_u32(obj) == 0 then
            return
        end

        local flags = read_u8(obj + someFlagsOffset)
        if forms.ischecked(detailsForm.tangibleCheckbox) then
            flags = bit.set(flags, 0)
        else
            flags = bit.clear(flags, 0)
        end
        write_u8(obj + someFlagsOffset, flags)

        for i = 1, #detailsForm.watches do
            detailsForm.watches[i]:applyEdits()
        end
    end

    local result = pcall(inner)
    if not result then
        console.log("Failed to apply changes. Ensure your inputs are in the correct format.")
    end
end

function getNewObjects(first, second)
    local list = {}
    for key in pairs(first) do
        if second[key] == nil then
            list[#list + 1] = key
        end
    end
    return list
end

function refreshObjectsList()
    -- Update objects list
    local currentObjects = {}
    local addrCurrentNode = GetFirstObject()
    objectCount = 0
    while true do
        addrCurrentNode = GetNextObject(addrCurrentNode)
        if addrCurrentNode == 0 then
            break
        end

        if currentObjects[addrCurrentNode] ~= nil then
            error("Encountered repeat object. This indicates memory is corrupt or the script thinks you're in a level when you're not.")
        end

        currentObjects[addrCurrentNode] = true
        objectCount = objectCount + 1
        if objectCount > 200 then
            error("Error: Found over 200 objects. This probably means there is a problem, because there shouldn't be that many objects.")
        end
    end

    -- Which objects are new, which despawned?
    local despawned = getNewObjects(allObjects, currentObjects)
    local newObjs = getNewObjects(currentObjects, allObjects)
    spawnActivity = #newObjs > 0 or #despawned > 0
    for i = 1, #newObjs do
        local objType = read_u16(newObjs[i] + typeOffset)
        local text = objectTypes[objType]
        if text == nil then
            text = "Unknown (Type 0x" .. hex(objType) .. ")"
        end
        console.log("Spawned " .. text)
    end
    for i = 1, #despawned do
        local objType = read_u16(despawned[i] + typeOffset)
        local text = objectTypes[objType]
        if text == nil then
            text = "Unknown (Type 0x" .. hex(objType) .. ")"
        end
        console.log("Despawned " .. text)
    end

    allObjects = currentObjects
end

local dropDownItems = nil
function refreshObjectDropDownList()
    dropDownItems = {}
    objectsByDropDown = {}
    for key in pairs(allObjects) do
        local objType = read_u16(key + typeOffset)
        local text = objectTypes[objType]
        if text == nil then
            text = "Unknown (Type 0x" .. hex(objType) .. ")"
        end
        text = text
        dropDownItems[#dropDownItems + 1] = text
        objectsByDropDown[#objectsByDropDown + 1] = key
    end
end
function refreshObjectDropDown(dropDown, previousSelectedObj)
    -- BizHawk is stupid and attempts to set SelectedIndex to 0 after updating the list
    if #dropDownItems == 0 then
        forms.setdropdownitems(dropDown, { "No objects" }, false)
    else
        forms.setdropdownitems(dropDown, dropDownItems, false)
    end
    forms.setproperty(dropDown, "SelectedIndex", -1)
    for i = 1, #objectsByDropDown do
        if objectsByDropDown[i] == previousSelectedObj then
            forms.setproperty(dropDown, "SelectedIndex", i - 1)
        end
    end
end

while not shouldExit do
    refreshObjectsList()
    if spawnActivity then
        forms.settext(mainForm.countLabel, "Number of objects: " .. objectCount)
        local selectedIndex = forms.getproperty(mainForm.objectDropDown, "SelectedIndex")
        local selectedObject = objectsByDropDown[selectedIndex + 1]
        refreshObjectDropDownList()
        refreshObjectDropDown(mainForm.objectDropDown, selectedObject)
    end

    for key in pairs(detailForms) do
        updateDetails(detailForms[key])
    end

    emu.frameadvance()
end