MarioSwim

-- Written By Eumeus14

-- Simple swimming script for smw TASing (speed values in this script apply to Mario Game by Draconif)

-- Things to fix:
-- gui.drawtext does nothing
-- Could set it up so that the console only outputs the swimming direction one time when it is changed.

-- The address of Mario's speed
local speed = 0x00007B
-- Mario's maximum left/right swimming speeds
local maxSwimSpeedL = -20
local maxSwimSpeedR = 20
-- Mario's maximum left/right swimming speeds with an item
local maxItemSwimSpeedL = -34
local maxItemSwimSpeedR = 34
-- The direction the script will make mario swim
local swimDirection = 'Stopped'
-- EmulatorHeight is just used for ui stuff
local EmulatorHeight = client.bufferheight()
-- Boolean to track if Mario is holding an item or not. defaults to false.
local holdingItem = false


-- Functions

-- Checks for a water current and adjusts max swimming values accordingly
function CheckForWaterCurrent()
    -- Set speed to 0 and wait for a current to push Mario
    mainmemory.write_s8(speed, 0)
    -- Set carried item to 0. Otherwise, the current cannot overpower Mario.
    mainmemory.writebyte(0x00148F, 0)

    AdvanceFrames(2)
    if(mainmemory.read_s8(speed) < 0) then
        -- Current pushes all speed values 8 units left
        maxSwimSpeedL = maxSwimSpeedL - 8
        maxSwimSpeedR = maxSwimSpeedR - 8
        maxItemSwimSpeedL = maxItemSwimSpeedL - 8
        maxItemSwimSpeedR = maxItemSwimSpeedR - 8
        console.writeline('Leftward current detected. Adjusting speed values...')
    elseif(mainmemory.read_s8(speed) > 0) then
        -- Current pushes all speed values 8 units right
        maxSwimSpeedL = maxSwimSpeedL + 8
        maxSwimSpeedR = maxSwimSpeedR + 8
        maxItemSwimSpeedL = maxItemSwimSpeedL + 8
        maxItemSwimSpeedR = maxItemSwimSpeedR + 8
        console.writeline('Rightward current detected. Adjusting speed values...')
    else
        -- no adjustment needed
        console.writeline('No current detected.')
    end
end


-- Advance some number of frames
function AdvanceFrames(numFrames)
    client.unpause()
    for i = 1, numFrames do
        emu.frameadvance()
    end
    client.pause()
end


-- Determines which direction to swim
function DetermineSwimmingDirection()
    -- Get keyboard input for swimming direction
    local Keypresses = input.get()

    -- Check the keyboard inputs and adjust swimming direction accordingly
    if(Keypresses.A == true) then
        swimDirection = 'Left'
        console.writeline('Setting swim direction to left.')
    elseif(Keypresses.D == true) then
        swimDirection = 'Right'
        console.writeline('Setting swim direction to right.')
    elseif(Keypresses.S == true) then
        swimDirection = 'Stopped'
        console.writeline('Stopping swim.')
    end
end


-- Checks if Mario is currently holding an item
function CheckForHeldItem()
    if(mainmemory.readbyte(0x00148F) == 1) then
        holdingItem = true
    else
        holdingItem = false
    end
end


-- Swims
function DoSwimming()
    CheckForHeldItem()
    -- Not holding an item
    if(holdingItem == false) then
        -- Left
        if(swimDirection == 'Left') then
            if(mainmemory.read_s8(speed) ~= maxSwimSpeedL) then
                joypad.set({['Right']=false}, 1)
                joypad.set({['Left']=true}, 1)
            else
                joypad.set({['Right']=true}, 1)
                joypad.set({['Left']=false}, 1)
            end
        -- Right
        elseif(swimDirection == 'Right') then
            if(mainmemory.read_s8(speed) ~= maxSwimSpeedR) then
                joypad.set({['Right']=true}, 1)
                joypad.set({['Left']=false}, 1)
            else
                joypad.set({['Right']=false}, 1)
                joypad.set({['Left']=true}, 1)
            end
        end
    -- Holding an item
    else
        -- Left
        if(swimDirection == 'Left') then
            if(mainmemory.read_s8(speed) ~= maxItemSwimSpeedL) then
                joypad.set({['Right']=false}, 1)
                joypad.set({['Left']=true}, 1)
            else
                joypad.set({['Right']=true}, 1)
                joypad.set({['Left']=false}, 1)
            end
        -- Right
        elseif(swimDirection == 'Right') then
            if(mainmemory.read_s8(speed) ~= maxItemSwimSpeedR) then
                joypad.set({['Right']=true}, 1)
                joypad.set({['Left']=false}, 1)
            else
                joypad.set({['Right']=false}, 1)
                joypad.set({['Left']=true}, 1)
            end
        end
    end
end

-- main
savestate.save('MarioSwim')

CheckForWaterCurrent()

savestate.load('MarioSwim')

while( true ) do
    -- instructions for user
    gui.drawText(1, (EmulatorHeight - 65), 'Press A on the keyboard to swim left.')
    gui.drawText(1, (EmulatorHeight - 50), 'Press D on the keyboard to swim right.')
    gui.drawText(1, (EmulatorHeight - 35), 'Press S on the keyboard to stop swimming.')

    DetermineSwimmingDirection()

    DoSwimming()

    emu.yield()
end