-- 高さ2
-- a0 = 9
-- an+1 = an + 8
-- 最初の周回は1週目

local TORCH_INTERVAL = 12

---@param ForwardCount integer
local function MoveForwardImpl(ForwardCount)
    for i = 1, ForwardCount do
        if not turtle.forward() then return i - 1 end
    end
    return ForwardCount
end

local function TurnBack()
    turtle.turnLeft()
    turtle.turnLeft()
end

local function InventoryIsFull()
    for i = 1, 16 do
        if turtle.getItemCount(i) == 0 then return false end
    end
    return true
end

---@class WindmillManager
---@field LoopCount number
---@field DistanceFromLineStart number
---@field ReachedCrossDigPoint fun(self:WindmillManager)
---@field private __MoveOnEdge fun(self:WindmillManager, FirstTurnFunc:fun(), SecondTurnFunc:fun())
---@field private __MoveOnCrossLine fun(TurnFunc:fun(), FirstMoveCount:integer, SecondMoveCount:integer)
---@field private __MoveToChest fun(self:WindmillManager)
---@field private __MoveFromChest fun(self:WindmillManager)
---@field SaveItems fun(self:WindmillManager, DropList:"fun(Slot: integer):boolean")
---@field MoveForward fun(self:WindmillManager)
---@field ShouldPutTorch fun(self:WindmillManager):boolean
---@field GetLineDigCount fun(self:WindmillManager):integer
local WindmillManager = {}
WindmillManager.New = function ()
    return{
        LoopCount = 2,
        CurrentProcessLine = 1,
        DistanceFromLineStart = 0,
        ReachedCrossDigPoint = function(self)
            return 4 * self.LoopCount == self.DistanceFromLineStart
        end,
        __MoveOnEdge = function(self, FirstTurnFunc, SecondTurnFunc)
            for i = 1, self.LoopCount do
                MoveForwardImpl(4)
                FirstTurnFunc()
                MoveForwardImpl(4)
                if i == self.LoopCount then break end
                SecondTurnFunc()
            end
        end,
        __MoveOnCrossLine = function(TurnFunc, FirstMoveCount, SecondMoveCount)
            MoveForwardImpl(FirstMoveCount)
            TurnFunc()
            MoveForwardImpl(SecondMoveCount)
        end,
        __MoveToChest = function(self)
            self.TurnBack()
            local CrossDigPoint = self.LoopCount * 4
            if  CrossDigPoint < self.DistanceFromLineStart then
                self.__MoveOnCrossLine(turtle.turnLeft, self.DistanceFromLineStart - CrossDigPoint, CrossDigPoint)
            else
                MoveForwardImpl(self.DistanceFromLineStart)
                turtle.turnLeft()
                self:__MoveOnEdge(turtle.turnLeft, turtle.turnRight)
            end
        end,
        __MoveFromChest = function(self)
            self.TurnBack()
            local CrossDigPoint = self.LoopCount * 4
            if  CrossDigPoint < self.DistanceFromLineStart then
                self.__MoveOnCrossLine(turtle.turnLeft, CrossDigPoint, self.DistanceFromLineStart - CrossDigPoint)
            else
                self:__MoveOnEdge(turtle.turnRight, turtle.turnLeft)
                turtle.turnRight()
                MoveForwardImpl(self.DistanceFromLineStart)
            end
        end,
        SaveItems = function (self, AllowDropFunc)
            self:__MoveToChest()
            local CurrentSelectedSlot = turtle.getSelectedSlot()
            for i = 1, 16 do
                if AllowDropFunc(i) then
                    turtle.select(i)
                    turtle.dropUp()
                end
            end
            turtle.select(CurrentSelectedSlot)
            self:__MoveFromChest()
        end,
        MoveForward = function (self, ForwardCount)
            self.DistanceFromLineStart = self.DistanceFromLineStart + MoveForwardImpl(ForwardCount)
        end,
        ShouldPutTorch = function(self)
            return 1 == self.DistanceFromLineStart % TORCH_INTERVAL
        end,
        GetLineDigCount = function(self)
            return self.LoopCount * 8 - 5
        end,
        ToNext = function(self, ToNextLineFunc, ToNextLoopFunc)
            if self.CurrentProcessLine == 4 then
                ToNextLoopFunc()
                self.CurrentProcessLine = 1
                self.LoopCount = self.LoopCount + 1
            else
                ToNextLineFunc()
                self.CurrentProcessLine = self.CurrentProcessLine + 1
            end
        end
    }
end

---@param arr any[]
local function PrintArray(arr)
    local re = "["
    for i, v in ipairs(arr) do
        if i ~= 1 then re = re.."," end
        re = re..v
    end
    print(re.."]")
end

---@class ItemManager
---@field __ReservedSlot number
---@field __AllowDropWhenExceed boolean
---@field private __AllowSave boolean
---@field private __Slots integer[]
---@field private __Scanimpl fun(self: ItemManager, WhenFoundFunc: "fun(Slot: integer):void")
---@field Scan fun(self: ItemManager)
---@field private __GetItemSlot fun(self:ItemManager):integer|nil
---@field Place fun(self: ItemManager, place_fn: "fun():boolean,string"):boolean,string
---@field DropWhenExceed fun(self: ItemManager):void `AllowDropWhenExceed`が`true`のとき、手持ちに1slot分だけ残して後ろにアイテムをすべて吐き出す。`Scan`を呼んだのと同じ事後効果を持つ
---@field IsSavableSlot fun(self: ItemManager, Slot: integer):boolean
local ItemManager = {}
---@param ReservedSlot number 管理対象アイテムが必ず存在するスロット番号
---@param AllowDropWhenExceed boolean 一定数ストックした後はドロップを許可するか
---@param AllowSave boolean 一定数ストックを残してチェストへの格納を許可するか
ItemManager.New = function (ReservedSlot, AllowDropWhenExceed, AllowSave)
    local re = {
        __ReservedSlot = ReservedSlot,
        __AllowDropWhenExceed = AllowDropWhenExceed,
        __AllowSave = AllowSave,
        __Slots = {},
        ---@param self ItemManager
        ---@param WhenFoundFunc fun(Slot: integer)
        __Scanimpl = function (self, WhenFoundFunc)
            local init_slot = turtle.getSelectedSlot() -- 退避
            ---@type integer[]
            for i = 1, 16 do
                if i ~= self.__ReservedSlot then
                    turtle.select(i)
                    if turtle.compareTo(self.__ReservedSlot) then
                        WhenFoundFunc(i)
                    end
                end
            end
            turtle.select(init_slot)
        end,
        ---@param self ItemManager
        Scan = function (self)
            ---@type integer[]
            local re = { self.__ReservedSlot }
            self:__Scanimpl(function (Slot) table.insert(re, re) end)
            self.__Slots = re
            PrintArray(self.__Slots)
        end,
        ---使用するスロット番号を求める
        ---
        ---末尾のスロットから使うようにする
        ---@param self ItemManager
        __GetItemSlot = function (self)
            if #self.__Slots == 0 then
                return nil
            elseif 1 < #self.__Slots then
                return #self.__Slots
            elseif turtle.getItemCount(self.__Slots[#self.__Slots]) == 1 then
                return nil
            end
            return #self.__Slots
        end,
        ---@param self ItemManager
        ---@param place_fn fun():boolean,string
        Place = function (self, place_fn)
            local slot = self:__GetItemSlot()
            if not slot then return false end
            local init_slot = turtle.getSelectedSlot() -- 退避
            turtle.select(slot)
            local re, message = place_fn()
            PrintArray(self.__Slots)
            if re and turtle.getItemCount(self.__Slots[#self.__Slots]) == 0 then
                table.remove(self.__Slots, #self.__Slots)
            end
            turtle.select(init_slot)
            return re, message
        end,
        ---`AllowDropWhenExceed`が`true`のとき、手持ちに1slot分だけ残して後ろにアイテムをすべて吐き出す。`Scan`を呼んだのと同じ事後効果を持つ
        ---@param self ItemManager
        DropWhenExceed = function (self)
            if not self.__AllowDropWhenExceed then
                return
            end
            self:__Scanimpl(function (Slot)
                TurnBack()
                turtle.drop()
                TurnBack()
            end)
            self.__Slots = { self.__ReservedSlot }
        end,
        ---@param self ItemManager
        ---@param Slot integer
        IsSavableSlot = function(self, Slot)
            if self.__AllowSave then
                return Slot ~= self.__ReservedSlot
            end
            for _, value in ipairs(self.__Slots) do
                if Slot == value then
                    return false
                end
            end
            return true
        end
    }
    re:Scan()
    return re
end

local StoneManager = ItemManager.New(2, true, true)
local TorchManager = ItemManager.New(1, false, false)
---@param Slot integer
local function IsSavableSlot(Slot)
    --TorchManagerのほうの探索はforが回るので重い
    return StoneManager:IsSavableSlot(Slot) and TorchManager:IsSavableSlot(Slot)
end

local Windmill = WindmillManager.New()

local function SaveItems()
    WindmillManager:SaveItems(IsSavableSlot)
end

local function DigForward()
    if turtle.detect() and InventoryIsFull() then SaveItems() end
    while turtle.detect() do
        local Flag, Message = turtle.dig()
        if not Flag then return Flag, Message end
    end
    return true
end

local function DigUp()
    if InventoryIsFull() then SaveItems() end
    return turtle.digUp()
end

---@param TryCount integer
local function DigAndMoveForward(TryCount)
    for i = 1, TryCount do
        DigForward()
        Windmill:MoveForward(1)
        DigUp()
        if not turtle.detectDown() then StoneManager:Place(turtle.placeDown) end
    end
end

local function NormalFlow()
    local DigMaxCount = Windmill:GetLineDigCount()
    for i = 1, DigMaxCount do
        DigAndMoveForward(1)
        if i == 1 then
            TurnBack()
            TorchManager:Place(turtle.place)
            TurnBack()
        end
        if Windmill:ReachedCrossDigPoint() then
            turtle.turnRight()
            for j = 1, 3 do
                -- 進行マス数カウントやインベントリチェックが行われると戻るコードが働かないのでラッパー不使用
                turtle.dig()
                turtle.forward()
                turtle.digUp()
            end
            for j = 1, 3 do turtle.back() end
            turtle.turnLeft()
        end
        if Windmill:ShouldPutTorch() then
            StoneManager:DropWhenExceed()
            TurnBack()
            TorchManager:Place(turtle.place)
            TurnBack()
        end
    end
    StoneManager:DropWhenExceed()
end

local function PlaceTorchToBack()
    TurnBack()
    TorchManager:Place(turtle.place)
    TurnBack()
end

local function ToNextLineLatterHalfProcess()
    turtle.turnLeft()
    for i = 1, 4 do DigAndMoveForward(1) end
    TurnBack()
    for i = 1, 4 do
        turtle.forward()
        if i == 1 then PlaceTorchToBack() end
    end
end

local function ToNextLine()
    for i = 1, 5 do
        DigAndMoveForward(1)
        if i == 2 then PlaceTorchToBack() end
    end
    ToNextLineLatterHalfProcess()
end

local function ToNextLoopLatterHalfProcess()
    turtle.turnRight()
    turtle.dig()
    turtle.forward()
    turtle.digDown()
    turtle.down()
    DigAndMoveForward(3)
    ToNextLineLatterHalfProcess()
end

local function Initialize()
    local TurningPointProcessByInitialize = function()
        turtle.turnLeft()
        DigAndMoveForward(4)
        turtle.back()
        TorchManager:Place(turtle.place)
        TurnBack()
        DigAndMoveForward(3)
        turtle.turnRight()
        if turtle.detect() then
            -- print("Initialize:: detected")
            DigAndMoveForward(3)
            for i = 1, 3 do turtle.back() end
        end
        turtle.turnLeft()
        -- print("Initialize:: after when detected")
        DigAndMoveForward(1)
        TurnBack()
        TorchManager:Place(turtle.place)
        TurnBack()
    end
    -- print("Initialize:: phase 1")
    DigAndMoveForward(4)
    TurningPointProcessByInitialize()
    -- print("Initialize:: phase 2")
    DigAndMoveForward(3)
    TurningPointProcessByInitialize()
    for i = 1, 3 do
        DigAndMoveForward(i == 3 and 6 or 7)
        if i == 3 then break end
        TurningPointProcessByInitialize()
    end
    ToNextLoopLatterHalfProcess()
end

local function ToNextLoop()
    turtle.up()
    MoveForwardImpl(5)
    turtle.turnLeft()
    MoveForwardImpl(4)
    ToNextLoopLatterHalfProcess()
end

Initialize()
while true do
    NormalFlow()
    Windmill:ToNext(ToNextLine, ToNextLoop)
end