Quarry for CC:Restitched

local TRASH = {
    ["minecraft:cobblestone"] = true,
    ["minecraft:dirt"] = true,
    ["minecraft:gravel"] = true,
    ["minecraft:stone"] = true,
    ["minecraft:netherrack"] = true,
}

local width = tonumber(arg[1])
local length = tonumber(arg[2])
local depth = tonumber(arg[3])

if not (width and length and depth) then
    print("Usage: quarry <width> <length> <depth>")
    return
end

local posX, posY, posZ = 0, 0, 0
local dir = 0 -- 0=north,1=east,2=south,3=west
local startX, startY = 0, 0
local surfaceZ = 0 -- constant chest height

local function compactInventory()
    for i = 1, 15 do
        local detail_i = turtle.getItemDetail(i)
        if detail_i then
            for j = i + 1, 16 do
                local detail_j = turtle.getItemDetail(j)
                if detail_j and detail_j.name == detail_i.name then
                    turtle.select(j)
                    turtle.transferTo(i)
                end
            end
        end
    end
    turtle.select(1)
end

local function dropTrash()
    compactInventory()
    for slot = 1, 16 do
        local detail = turtle.getItemDetail(slot)
        if detail and TRASH[detail.name] then
            turtle.select(slot)
            turtle.drop()
        end
    end
    turtle.select(1)
end

local function depositItems()
    compactInventory()
    for slot = 1, 16 do
        local detail = turtle.getItemDetail(slot)
        if detail and not TRASH[detail.name] then
            turtle.select(slot)
            turtle.drop()
        end
    end
    turtle.select(1)
end

local function tryDigForward()
    while turtle.detect() do
        if not turtle.dig() then return false end
        sleep(0.2)
    end
    return true
end

local function tryDigUp()
    while turtle.detectUp() do
        if not turtle.digUp() then return false end
        sleep(0.2)
    end
    return true
end

local function tryDigDown()
    while turtle.detectDown() do
        if not turtle.digDown() then return false end
        sleep(0.2)
    end
    return true
end

local function forward()
    while not turtle.forward() do
        if not tryDigForward() then return false end
        sleep(0.2)
    end
    if dir == 0 then posY = posY + 1
    elseif dir == 1 then posX = posX + 1
    elseif dir == 2 then posY = posY - 1
    elseif dir == 3 then posX = posX - 1
    end
    return true
end

local function back()
    while not turtle.back() do sleep(0.2) end
    if dir == 0 then posY = posY - 1
    elseif dir == 1 then posX = posX - 1
    elseif dir == 2 then posY = posY + 1
    elseif dir == 3 then posX = posX + 1
    end
    return true
end

local function up()
    while not turtle.up() do
        if not tryDigUp() then return false end
        sleep(0.2)
    end
    posZ = posZ - 1
    return true
end

local function down()
    while not turtle.down() do
        if not tryDigDown() then return false end
        sleep(0.2)
    end
    posZ = posZ + 1
    return true
end

local function right()
    turtle.turnRight()
    dir = (dir + 1) % 4
    return true
end

local function left()
    turtle.turnLeft()
    dir = (dir - 1) % 4
    if dir < 0 then dir = dir + 4 end
    return true
end

local function turnTo(targetDir)
    local diff = (targetDir - dir) % 4
    if diff == 3 then
        left()
    else
        for i = 1, diff do
            right()
        end
    end
end

local function moveForwardN(n)
    for _ = 1, n do
        if not forward() then
            error("Failed moving forward")
        end
    end
end

local function returnToStartHorizontal()
    if posX > startX then
        turnTo(3)
        moveForwardN(posX - startX)
    elseif posX < startX then
        turnTo(1)
        moveForwardN(startX - posX)
    end

    if posY > startY then
        turnTo(2)
        moveForwardN(posY - startY)
    elseif posY < startY then
        turnTo(0)
        moveForwardN(startY - posY)
    end

    turnTo(0)
end

local function returnToChestSurface()
    -- Move horizontally to startX, startY
    returnToStartHorizontal()
    -- Move vertically to surfaceZ
    while posZ > surfaceZ do
        if not up() then return false end
    end
    while posZ < surfaceZ do
        if not down() then return false end
    end
    -- Face south (direction 2) so front faces chest
    turnTo(2)
    return true
end

-- When depositing items after return:
depositItems()

-- Then turn 180° to face quarry again
right()
right()

local function mine3LayerColumn(digForward)
    if not tryDigUp() then return false end
    if digForward and not tryDigForward() then return false end
    if not tryDigDown() then return false end
    return true
end

local function getLayerZ(layer)
    return surfaceZ + (layer - 1) * 3
end

local function moveToZ(targetZ)
    while posZ < targetZ do
        if not down() then
            print("Cannot move down to next layer.")
            return false
        end
    end
    while posZ > targetZ do
        if not up() then
            print("Cannot move up to next layer.")
            return false
        end
    end
    return true
end

-- Initialize start position & surface chest height
startX, startY, surfaceZ = posX, posY, posZ
posZ = surfaceZ

for layer = 1, depth do
    print("Starting layer "..layer..", posZ="..posZ)
    local goingForward = true

    for row = 1, length do
        if goingForward then
            turnTo(0)
        else
            turnTo(2)
        end

        for col = 1, width do
            local digForward = (col < width)

            if not mine3LayerColumn(digForward) then
                print("Unmineable block or bedrock reached. Stopping.")
                if not returnToChestSurface() then
                    print("Failed returning to surface chest.")
                else
                    depositItems()
                end
                return
            end

            if col == width then
                dropTrash()
            end

            if col < width then
                if not forward() then
                    print("Failed to move forward. Stopping.")
                    if not returnToChestSurface() then
                        print("Failed returning to surface chest.")
                    else
                        depositItems()
                    end
                    return
                end
            end
        end

        if row < length then
            if goingForward then
                right()
                if not forward() then
                    print("Failed to move right. Stopping.")
                    if not returnToChestSurface() then
                        print("Failed returning to surface chest.")
                    else
                        depositItems()
                    end
                    return
                end
                right()
            else
                left()
                if not forward() then
                    print("Failed to move left. Stopping.")
                    if not returnToChestSurface() then
                        print("Failed returning to surface chest.")
                    else
                        depositItems()
                    end
                    return
                end
                left()
            end
            goingForward = not goingForward
        end
    end

    print("Completed layer "..layer)

    print("Returning to surface chest to deposit items...")
    if not returnToChestSurface() then
        print("Failed returning to surface chest.")
        return
    end
    depositItems()

    if layer < depth then
        local nextLayerZ = getLayerZ(layer + 1)
        if not moveToZ(nextLayerZ) then
            print("Failed to move down to next layer.")
            if not returnToChestSurface() then
                print("Failed returning to surface chest.")
            else
                depositItems()
            end
            return
        end
        print("Moved vertically to next layer "..(layer + 1).." at posZ "..posZ)
    end
end

print("Quarry complete, returning to surface chest.")
if returnToChestSurface() then
    depositItems()
end
print("Done!")