-- This script is for a Japanese version of 'A Link to the Past', or 'Zelda no Densetsu - Kamigami no Triforce'.

-- for fastforwarding to the frame
function toFrame(frame)
    if movie.framecount() -1 > frame then
        emu.pause()
    end
end

-- for rough indication of the next input frame
lastLagFr = 0
function lastLag()
    if emu.lagged() then
        lastLagFr = movie.framecount() - 2
    end
    gui.text(0, 0, string.format("%d",lastLagFr))
end

local eHP={}            -- enemy HP
local eHPDisp={}        -- enemy HP Display
local itemDrop={}       -- item Drop (prize pack manipulation)
local eX = {}           -- enemy's X position
local eY = {}           -- enemy's Y position
local relEneX = {}      -- relative enemy's X position, (enemy's X postion) - (camara's X position), actually means top-left X position of enemy's hitbox
local relEneY = {}      -- relative enemy's Y position, (enemy's Y postion) - (camara's Y position), actually means top-left Y position of enemy's hitbox

-- reads RAM
function ramRead()
    rupee = memory.readword(0x7EF360)       -- rupee
    numBomb = memory.readbyte(0x7EF343)     -- number of bombs for after YBA with spin attack
    numArrows = memory.readbyte(0x7EF377)   -- number of arrows for after YBA with spin attack
    x = memory.readbyte(0x7E0022)           -- Link's X position
    y = memory.readbyte(0x7E0020)           -- Link's Y position
    pos = string.format("(%2x,%2x)",x,y)    -- means Link's position, (X, Y). I think HEXed value is more useful.
    cameraX = memory.readbyte(0x7E011E)     -- camera's X
    cameraY = memory.readbyte(0x7E0122)     -- camera's Y
    hitX = (x-cameraX) % 256                -- top-left X position of Link's hitbox
    hitY = (y-cameraY) % 256                -- top-left Y position of Link's hitbox
    gui.box(hitX, hitY, hitX+16, hitY+24)   -- displaying Link's hitbox

    -- assigns enemy's HP, X and Y position, and top-left X and Y position of enemy's hitbox
    for i=0,8 do
        eHP[i] = memory.readbyte(0x7E0E50+i)
        eHPDisp[i]=string.format("%3d",eHP[i])
        eX[i] = memory.readbyte(0x7E0D10+i)
        eY[i] = memory.readbyte(0x7E0D00+i)
        relEneX[i] = (eX[i] - cameraX) % 256
        relEneY[i] = (eY[i] - cameraY) % 256
    end
    HP=memory.readbyte(0x7EF36D)                        -- Link's HP
    string.format("%3d",HP)
    MP=memory.readbyte(0x7EF36E)                        -- Link's MP
    string.format("%3d",MP)
    xSpeed=memory.readbytesigned(0x7E0031)              -- Link's X speed
    ySpeed=memory.readbytesigned(0x7E0030)              -- Link's Y speed
    posSpeed = string.format(" %2d,%2d ",xSpeed,ySpeed) -- means Link's (X speed, Y speed)

    peg=memory.readbyte(0x7E0374)                       -- 0=pegasus boots dash; 29=spin dash
    bomb=memory.readbyte(0x7E03A0)                      -- timer for exploding a bomb
    spinAttack=memory.readbyte(0x7E0079)                -- charging time for spin attack
    rng=memory.readword(0x7E0FA0)                       -- RNG
    grab=memory.readbyte(0x7E0DFF)                      -- timer for grabbing

    --[[    -- assigns prize pack manipulation, but this code does not display for the lack of gui.text. should use 'RAM Watch.'
    for i=0,6 do
        itemDrop[i]=memory.readbyte(0x7E0FC7+i)
    end
    -- Quards, Rupees, Magic, Bombs, Arrows, Skeleton, Big
    --]]

    --[[
    layer=memory.readbyte(0x7E0476)         -- Link's current Layer
    0x7E00A0                                -- Link's current room for EG. HEXed value should be used on 'RAM Watch.'
    -]]

    p=string.format("peg %2d",peg)
    s=string.format("spn %2x",spinAttack)
    b=string.format("bom %2d",bomb)
    r=string.format("rng %4x",rng)
    g=string.format("grb %2d",grab)

    status = memory.readbyte(0x7E004D)      -- Link's current status. 0=able to be inputted.
    recoil = memory.readbyte(0x7E0046)      -- Link's current recoiling status. 0=able to be inputted.
    push = memory.readbyte(0x7E0371) - 13   -- state of pushing a block. 0=begin to move the block.
    ledge = memory.readbyte(0x7E0375)       -- Link's current ledge off status. 0=begin to ledge off. used when you don't have pegasus boots.
    motion = memory.readbyte(0x7E0354)      -- Link's current motion (slashing, using staff, arrow, etc). 0=able to be inputted.

    gui.text(116,0,string.format("mtn %d ldg %d sta %d rcl %d psh %d",motion,ledge,status,recoil,push)) -- displaying above 5 things.
end

-- auto scroll text messages. when msgWait is not 0, you have to scroll them manually.
function autoMsg()
    windowBox = memory.readword(0x7E0010)
    msg = memory.readbyte(0x7E1CE9) - 1
    msgWait = memory.readbyte(0x7E1CE0)
    gui.text(40, 0, string.format("%d %d %X", msg, msgWait, windowBox))
    if windowBox == 0x20E then
        if msg == 0 then
            joypad.set(1, {A=1})
        end
    --[[
        if (msgWait > 0) then
        joypad.set(1, {A=1})
        -- emu.pause()
        end
    --]]
    end
end

-- the next function is auto-displaying the last frame of no input available
lastGameMode = 0
lastStatus = 0
lastRecoil = 0
lastMotion = 0
function chkNoInput()
    gameMode = bit.band(windowBox,0xFF00)

    if gameMode > 0 then
        lastGameMode = movie.framecount()+1
    end
    if status > 0 then
        lastStatus = movie.framecount()+1
    end
    if recoil > 0 then
        lastRecoil = movie.framecount()+1
    end
    if motion > 0 then
        lastMotion = movie.framecount()
    end

    gui.text(80,0,string.format("%d",lastGameMode))
    gui.text(204,7,string.format("%d",lastStatus))
    gui.text(128,7,string.format("%d",lastMotion))
    -- gui.text(210,7,string.format("%d",lastRecoil))
end

-- displays Link's position and |velocity|
function position()
    gui.text(228,208,pos)
    gui.text(228,200,posSpeed)
end

-- displays enemie's HP and a hitbox
function eHPF()
    for j=0,8 do
        if (eHP[j] ~= 0) and (eHP[j] < 250) then
            gui.text(240,0+(j)*8,eHPDisp[j])
            gui.box(relEneX[j], relEneY[j], relEneX[j]+16, relEneY[j]+24)

            -- this meant to target enemies with arrows or stuffs.
            --[[
            gui.line(relEneX[j]+8, 0, relEneX[j]+8, 225)
            gui.line(0, relEneY[j]+12, 255, relEneY[j]+12)
            --]]
            --[[
            gui.line(relEneX[j], 0, relEneX[j], 225)
            gui.line(0, relEneY[j], 255, relEneY[j])
            gui.line(relEneX[j]+16, 0, relEneX[j]+16, 225)
            gui.line(0, relEneY[j]+24, 255, relEneY[j]+24)
            --]]

        end
    end
end

-- displays Link's HP and MP
function HPDisp()
    gui.text(166,14,HP)
    gui.text(22,60,MP)
end

-- displays Link's various states
function state()
    gui.text(220,152,p)     -- 0=pegasus boots dash; 29=spin dash
    gui.text(220,160,s)     -- charging time for spin attack
    gui.text(220,168,b)     -- timer for exploding a bomb
    gui.text(220,176,g)     -- timer for grabbing
    gui.text(220,188,r)     -- RNG
end

-- displays the number of rupees, bombs and arrows for after YBA with spin attack
function RupeeBombArrow()
    gui.text(80,16,rupee)
    gui.text(108,16,numBomb)
    gui.text(128,16,numArrows)
end

-- for chest game and digging game or something. repeats input with one frame delay
function try()
    emu.speedmode("turbo")
    local state = savestate.create()
    savestate.save(state)
    local try1=0
    for i=1,1000 do
        savestate.load(state)
        emu.frameadvance()
        savestate.save(state)
        for j=1,500 do
            -- joypad.set(1,{A=1})
            joypad.set(1,{Y=1})

            gui.text(16,52,try1)
            emu.frameadvance()
        end
        try1=try1+1
    end
end

while true do
    lastLag()               -- for rough indication of the next input frame
    ramRead()               -- reads RAM
    autoMsg()               -- auto scroll text messages. when msgWait is not 0, you have to scroll them manually.
    RupeeBombArrow()        -- displays the number of rupees, bombs and arrows for after YBA with spin attack
    position()              -- displays Link's position and |velocity|
    eHPF()                  -- displays enemie's HP and a hitbox
    HPDisp()                -- displays Link's HP and MP
    -- toFrame(205000)      -- for fastforwarding to the frame
    state()                 -- displays Link's various states
    chkNoInput()            -- the next function is auto-displaying the last frame of no input available.
    -- try()                -- for chest game and digging game or something. repeats input with one frame delay

    emu.frameadvance()
end