turtle_start

dirTable = {{0, 1}, {-1, 0}, {0, -1}, {1, 0}}

posX = 0
posY = 0
posZ = 0

dir = 1

fuel = 0

protectedBlocks = {'computercraft:turtle_normal', 'computercraft:turtle_advanced'}
protectedChunks = {}
nodes = {}

function GetPosition()
    x, y, z = gps.locate()
    if x ~= nil then --Recieved our position
        posX, posY, posZ = x, y, z
        return true
    end

    return false
end

function UpdatePChunkLoop()
    rednet.open('left')
    while true do
        sender,message,distance = rednet.receive("V_PC")
        protectedChunks = textutils.unserialise(message)
    end
end

local function has_value (tab, val)
    for index, value in ipairs(tab) do
        if value == val then
            return true
        end
    end

    return false
end

function IsTurtle(name)
    if name == protectedBlocks[1] or name == protectedBlocks[2] then
        return true
    end

    return false
end

function IsInProtectedChunk()
    chunkX = math.floor(posX/16)
    chunkZ = math.floor(posZ/16)

    if has_value(protectedChunks, chunkX..','..chunkZ) then
        return true
    end

    return false
end

function ifProtected(data, ignorePChunk)
    -- Check if block is turtle
    if IsTurtle(data.name) then
        return true
    end

    if ignorePChunk then
        return false
    end

    return IsInProtectedChunk()
end

function DirToCoords(direction)
    x = dirTable[direction][1]
    z = dirTable[direction][2]

    return x, z
end

function IncrementDir(amount)
    if dir + amount > 4 then
        dir = 1
    elseif dir + amount < 1 then
        dir = 4
    end
end

function Forward(ignorePChunk)
    success, data = turtle.inspect()
    if ifProtected(data, ignorePChunk) ~= true then
        if success then
            turtle.dig('right')
        end
        if turtle.forward() then
            x, z = DirToCoords(dir)
            posX = posX + x
            posZ = posZ + z
            return true
        end
    end
    return false
end

function Up(ignorePChunk)
    success, data = turtle.inspect()
    if ifProtected(data, ignorePChunk) ~= true then
        if success then
            turtle.digUp('right')
        end
        if turtle.up() then
            posY = posY + 1
            return true
        end
    end
    return false
end

function Down(ignorePChunk)
    success, data = turtle.inspect()
    if ifProtected(data, ignorePChunk) ~= true then
        if success then
            turtle.digDown('right')
        end
        if turtle.down() then
            posY = posY - 1
            return true
        end
    end
    return false
end

function ToWorldHeight()
    while true do
        success, data = turtle.inspectUp()
        if success then -- If a block above
            while true do
                success, data = turtle.inspectUp()
                if IsTurtle(data.name) == false then
                    break
                end
                Forward(true) -- Otherwise go forward and try again
            end

            turtle.digUp()
        end

        if turtle.up() == false then --Reached height limit
            break
        end
    end
end

function OutOfFuelCall()
    while true do
        if fuel <= 1 then
            rednet.broadcast("OUT OF FUEL X"..posX..', Y'..posY..', Z'..posZ, "V_M")
            fuel = turtle.getFuelLevel()
        end
        sleep(60)
    end
end

function DownUntil()
    while true do
        success, data = turtle.inspectDown()

        if success then
            if IsTurtle(data.name) then
                sleep(1)
            else
                break -- We reached a block that is not a tutel
            end
        else
            if turtle.down() then
                posY = posY - 1
            end
        end
    end
end

function Refuel()
    for i=1, 16 do
        turtle.select(i)
        turtle.refuel()
        if turtle.getFuelLevel() == turtle.getFuelLimit() then
            break
        end
    end
    fuel = turtle.getFuelLevel()

    turtle.select(1)
end

function LeaveProtectedChunk()
    ToWorldHeight()
    while true do
        Forward(true)
        if IsInProtectedChunk() == false then
            break
        end
    end
    DownUntil()
end

function Dump()
    for i=1, 16 do
        turtle.select(i)
        turtle.dropDown()
    end
    turtle.select(1)
end

function ToNode()
    print('Moving to node...')
    -- Face south
    print('Facing south...')
    while true do
        if dir == 1 then
            break
        end
        turtle.turnRight()
        IncrementDir(1)
    end

    -- Go to height limit
    print('Moving to world height...')
    ToWorldHeight()

    -- Get nodes
    rednet.broadcast("Node request", "V_RN")

    nodes = {}
    while true do
        sender,message,distance = rednet.receive("V_N", 2)
        if message == nil then
            break
        end
        print('Recieved a node')
        table.insert(nodes, {textutils.unserialise(message), distance})
    end

    -- Choose nearest node
    closestNode = {0,0}
    closestDist = 99999999
    for i=1,#nodes do
        nX = nodes[i][1][1]
        nZ = nodes[i][1][2]
        nDist = math.sqrt(math.pow(nX - posX, 2) + math.pow(nZ - posZ, 2))
        if nDist < closestDist then
            closestNode = nodes[i][1]
            closestDist = nDist
        end
    end

    print('Moving to node at '..closestNode[1]..', '..closestNode[2])

    -- Go to node
    if closestNode[1] > posX then
        turtle.turnLeft()
        IncrementDir(-1)
        while posX ~= closestNode[1] do
            Forward(true)
        end
        turtle.turnRight()
        IncrementDir(1)
    else
        turtle.turnRight()
        IncrementDir(1)
        while posX ~= closestNode[1] do
            Forward(true)
        end
        turtle.turnLeft()
        IncrementDir(-1)
    end
    print('Arrived at node X')

    if closestNode[2] > posZ then
        while posZ ~= closestNode[2] do
            Forward(true)
        end
    else
        turtle.turnLeft()
        turtle.turnLeft()
        IncrementDir(-2)
        while posZ ~= closestNode[2] do
            Forward(true)
        end
        turtle.turnRight()
        turtle.turnRight()
        IncrementDir(2)
    end
    print('Arrived at node Z')

    -- Go down until block is reached
    DownUntil()

    -- Recheck that we have arrived at a node
    while GetPosition() == false do
        rednet.broadcast("COULD NOT RESOLVE POSITION X"..posX..', Y'..posY..', Z'..posZ, "V_M")
        sleep(60)
    end

    if posX == closestNode[1] and posZ == closestNode[2] then
        -- Dump inventory into node
        Dump()

        -- Refuel
        turtle.select(1)
        while turtle.getFuelLevel() ~= turtle.getFuelLimit() do
            if turtle.suck(64) == false then
                sleep(5)
            end
            turtle.refuel(64)
        end

        -- Dump exess fuel
        Dump()

        -- Leave node area
        turtle.turnRight()
        turtle.forward()
        turtle.turnLeft()
        LeaveProtectedChunk()
    else
        rednet.broadcast("FAILED TO REACH NODE X"..closestNode[1]..', Z'..closestNode[2], "V_M")
        ToNode()
    end
end

function RunCommands()
    while true do
        sender,message,distance = rednet.receive("V_CT")
        if message == 'pos' then
            rednet.send(sender, 'pos '..posX..' '..posY..' '..posZ, "V_M")
        elseif message == 'upd' then
            shell.run('update.lua')
        end
    end
end

function Main()
    if IsInProtectedChunk() then
        print('Inside protected chunk!')
        LeaveProtectedChunk()
    end

    lastRot = 0
    lastV = 0
    while true do
        fuel = turtle.getFuelLevel()

        if fuel < 5000 or turtle.getItemCount(16) > 0 then
            ToNode()
        end

        while fuel <= 1 do
            rednet.broadcast("OUT OF FUEL X"..posX..', Y'..posY..', Z'..posZ, "V_M")
            fuel = turtle.getFuelLevel()
            sleep(60)
        end

        rand = math.random(5)

        if rand == 1 and lastRot ~= -1 then
            turtle.turnRight()
            IncrementDir(1)
            Forward(false)

            lastRot = 1
            lastV = 0
        elseif rand == 2 and lastRot ~= 1 then
            turtle.turnLeft()
            IncrementDir(-1)
            Forward(false)

            lastRot = -1
            lastV = 0
        elseif rand == 3 then
            Forward(false)
            lastV = 0
        elseif rand == 4 and lastV ~= -1 then
            Up(false)
            lastV = 1
        elseif lastV ~= 1 then
            Down(false)
            lastV = -1
        end
    end
end

print('Add fuel and equip tools')
print('Ensure Turtle is near gps node')
print('Ensure Turtle is facing south')

print('Initializing Turtle...')
Refuel()
turtle.select(1)
print('Fuel: '..turtle.getFuelLevel())

while GetPosition() == false do
    print('Could not resolve position. Ensure turtle is near functional GPS node')
    sleep(30)
end
print('Received position X'..posX..' Y'..posY..' Z'..posZ)

rednet.open('left')
rednet.broadcast('V_RPC', 'V_RPC')
sender,message,distance = rednet.receive("V_PC")
rednet.close()
protectedChunks = textutils.unserialise(message)
print('Received '..#protectedChunks..' protected chunks')

print('Initialization complete! m a y  t h e  v o i d  e m b r a c e  y o u')

parallel.waitForAll(UpdatePChunkLoop, Main, OutOfFuelCall, RunCommands)