TPS (Turtle Positioning System) for ComputerCraft

--[[
 Turtle Positioning System
 Use two turtles as an expensive and crappy GPS server! Use ALL the fuel!

 pastebin get PsTiQ5eu startup
 std PB PsTiQ5eu startup
--]]

local chestX = 0 --fill this in!
local chestY = 0 --fill this in!
local chestZ = 0 --fill this in!

local startx,starty,startz --if there isn't a file storing them
startx = 0
starty = 64
startz = 0

local chest = true

if not gps then --I love having comical error handling
    return printError("GPS API wasn't found. Are you using an older version of ComputerCraft?")
else
    if type(gps) == "table" then
        if not (gps.locate) then
            return printError("gps.locate seems to be missing.")
        else
            if type(gps.locate) == "string" then
                return printError("Is this a joke? gps.locate is a string. This does knot make sense.")
            elseif type(gps.locate) == "table" then
                return printError("What the... gps.locate is a table! Knock it off.")
            elseif type(gps.locate) == "number" then
                return printError("Eh? gps.locate is a number! This doesn't ADD UP!")
            end
        end
    end
end

local cfilename = ".coords"

local tArg = {...}
local modem = peripheral.find("modem")
if not turtle then
    if pocket then
        return printError("Hey, what do you think you're doing!? Turtles only! No pocket computer servers!!")
    else
        return printError("Um? This is a turtle program, you know?")
    end
end
if not modem then
    local l = peripheral.wrap("right")
    local r = peripheral.wrap("left")
    if r and l then
        return printError("Dangit, you messed up! Craft a WIRELESS turtle!")
    else
        return printError("You need a wireless modem.")
    end
end
modem.open(gps.CHANNEL_GPS)

local tew,tps
local requests = 0
local scr_x, scr_y = term.getSize()

local fuels = {
    ["minecraft:coal"] = 80,
    ["minecraft:coal_block"] = 80*9,
}

local dro = function(input)
    return input % 4
end

local fixNumber = function(num)
    return math.floor(num+0.5)
end

local getDist = function(x1,y1,z1,x2,y2,z2)
    return math.abs(x2-x1)+math.abs(y2-y1)+math.abs(z2-z1)
end

local directionNames = {
    [0] = "South",
    [1] = "West",
    [2] = "North",
    [3] = "East",
}

local dudes = {}

local total
--[[local sendRequests = function()
    while true do
        total = 0
        getEvents("tew_move","tew_receive")
        for k,v in pairs(dudes) do
            if v > 0 then
                modem.transmit( k, gps.CHANNEL_GPS, { tew.x, tew.y, tew.z } )
                dudes[k] = dudes[k] - 1
                requests = requests + 1
                total = total + 1
            end
        end
        tew.lock = (total == 0)
    end
end--]]

local sendRequest = function()
    total = 0
    for k,v in pairs(dudes) do
        if v > 0 then
            modem.transmit( k, gps.CHANNEL_GPS, { tew.x, tew.y, tew.z } )
            dudes[k] = dudes[k] - 1
            requests = requests + 1
            total = total + 1
        end
    end
    tew.lock = (total == 0)
end
local adjustCoords = function(dir, dist)
    if dir == -1 then
        tew.y = tew.y + 1
    elseif dir == -2 then
        tew.y = tew.y - 1
    else
        tew.x = fixNumber(tew.x - math.sin(math.rad(dir*90)))
        tew.z = fixNumber(tew.z + math.cos(math.rad(dir*90)))
    end
    tps(true)
end

local gotoCoords = function( gx, gy, gz )
    if (gx == tew.x) and (gy == tew.y) and (gz == tew.z) then return end

    local cx,cy,cz = tew.x,tew.y,tew.z

    while (gx ~= tew.x) or (gy ~= tew.y) or (gz ~= tew.z) do

        for a = 1, math.abs(gy-cy) do
            if tew.y == gy then break end
            tew.lock = false
            if gy > cy then
                tew.up()
            else
                tew.down()
            end
        end
        if tew.x ~= gx then
            tew.lock = false
            tew.turn(3)
            for a = 1, math.abs(gx-cx) do
                if tew.x == gx then break end
                tew.lock = false
                if gx > cx then
                    tew.forward()
                else
                    tew.back()
                end
            end
        end
        if tew.z ~= gz then
            tew.lock = false
            tew.turn(0)
            for a = 1, math.abs(gz-cz) do
                if tew.z == gz then break end
                tew.lock = false
                if gz > cz then
                    tew.forward()
                else
                    tew.back()
                end
            end
        end

    end
end

local saveTheWhales = function() --HOPEFULLY the path is unobstructed by blocks
    local bC = {
        x = tew.x,
        y = tew.y,
        z = tew.z,
        direction = tew.direction,
    }
    gotoCoords(chestX,((chestY>bC.y) and (chestY-1) or (chestY+1)),chestZ)
    for a = 1, 16 do
        if turtle.inspectUp() then
            turtle.suckUp()
        elseif turtle.inspectDown() then
            turtle.suckDown()
        elseif turtle.inspect() then
            turtle.suck()
        end
    end
    gotoCoords(bC.x,bC.y,bC.z)
    tew.lock = false
    tew.turn(bC.direction)
end

local checkIfCanFuel = function()
    local currentSlot = turtle.getSelectedSlot()
    for a = 1, 16 do
        local item = turtle.getItemDetail(a)
        if item then
            if fuels[item.name] then
                return true
            end
        end
    end
    return false
end

local doRefuel = function()
    while true do
        local currentSlot = turtle.getSelectedSlot()
        for a = 1, 16 do
            local item = turtle.getItemDetail(a)
            if item then
                if fuels[item.name] then
                    turtle.select(a)
                    turtle.refuel(1)
                    turtle.select(currentSlot)
                    term.setCursorPos(1,scr_y)
                    term.clearLine()
                    return true
                end
            end
        end
        sleep(0) --INSERT MORE FUEL!
        term.setCursorPos(1,scr_y)
        term.write("Insert more fuel!!")
    end
    return false
end

local handleFuel = function(chest)
    if type(turtle.getFuelLevel()) == "number" then
        if chest and (not checkIfCanFuel()) then
            local dist = getDist(tew.x,tew.y,tew.z,chestX,chestY,chestZ)
            if dist+10 > turtle.getFuelLevel() then --gives me some leeway
                saveTheWhales() --PANIC
                doRefuel()
            end
        end
        if turtle.getFuelLevel() == 0 then
            doRefuel()
        end
    else
        return true
    end
end

-- 'tew' is a reproduction of the turtle API, but tracked and written to a file located at cfilename (default: "/.coords")

tew = { --already localized
    lock = false,
    direction = 0,
    x = startx,
    y = starty,
    z = startz,
    forward = function(dist,doFuelThing)
        local success, msg
        for a = 1, dist or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            handleFuel(doFuelThing)
            success, msg = turtle.forward()
            if success then
                adjustCoords(dro(tew.direction),1)
                --os.queueEvent("tew_move")
                sendRequest()
            else
                return success, msg
            end
        end
        return true
    end,
    back = function(dist,doFuelThing)
        local success, msg
        for a = 1, dist or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            handleFuel(doFuelThing)
            success, msg = turtle.back()
            if success then
                adjustCoords(dro(tew.direction+2),1)
                --os.queueEvent("tew_move")
                sendRequest()
            else
                return success, msg
            end
        end
        return true
    end,
    up = function(dist,doFuelThing)
        local success, msg
        for a = 1, dist or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            handleFuel(doFuelThing)
            success, msg = turtle.up()
            if success then
                adjustCoords(-1,1)
                --os.queueEvent("tew_move")
                sendRequest()
            else
                return success, msg
            end
        end
        return true
    end,
    down = function(dist,doFuelThing)
        local success, msg
        for a = 1, dist or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            handleFuel(doFuelThing)
            success, msg = turtle.down()
            if success then
                adjustCoords(-2,1)
                --os.queueEvent("tew_move")
                sendRequest()
            else
                return success, msg
            end
        end
        return true
    end,
    turnRight = function(times,doFuelThing)
        handleFuel(doFuelThing)
        for a = 1, times or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            turtle.turnRight()
            tew.direction = dro(tew.direction+1)
            tps(true)
        end
        return true
    end,
    turnLeft = function(times,doFuelThing)
        handleFuel(doFuelThing)
        for a = 1, times or 1 do
            if tew.lock then repeat sleep(0) until not tew.lock end
            turtle.turnRight()
            tew.direction = dro(tew.direction+1)
            tps(true)
        end
        return true
    end,
    turn = function(dir)
        if dir == tew.direction then return true end
        repeat
            tew.turnRight()
        until tew.direction == dir
        return true
    end
}

tps = function( doWrite )
    if doWrite then
        local file = fs.open(cfilename,"w")
        file.write(tew.x.."\n"..tew.y.."\n"..tew.z.."\n"..tew.direction.."\n"..chestX.."\n"..chestY.."\n"..chestZ)
        file.close()
    else
        if not fs.exists(cfilename) then tps(true) end
        local file = fs.open(cfilename,"r")
        tew.x = tonumber(file.readLine())
        tew.y = tonumber(file.readLine())
        tew.z = tonumber(file.readLine())
        tew.direction = tonumber(file.readLine())
        chestX = tonumber(file.readLine())
        chestY = tonumber(file.readLine())
        chestZ = tonumber(file.readLine())
        file.close()
    end
end

tps(false)
tew.lock = true

local doTurtleMove = function()
    while true do
        tew.forward(   1,true)
        tew.turnRight( 1,true)
        tew.forward(   1,true)
        tew.up(        1,true)
        tew.turnRight( 1,true)
        tew.forward(   1,true)
        tew.turnRight( 1,true)
        tew.forward(   1,true)
        tew.down(      1,true)
        tew.turnRight( 1,true)
    end
end

local handleRequests = function() --also handles manual exit
    local evt, side, chan, repchan, message, distance
    while true do
        evt, side, chan, repchan, message, distance = os.pullEvent()
        if evt == "modem_message" then
            if (chan == gps.CHANNEL_GPS) and (message == "PING") then
                dudes[repchan] = 4
                --os.queueEvent("tew_receive")
                sendRequest()
            end
        elseif evt == "key" then
            if side == keys.x then
                return
            end
        end
    end
end

local getEvents = function(...)
    local evt
    while true do
        evt = {os.pullEvent()}
        for a = 1, #arg do
            if arg[a] == evt[1] then
                return unpack(evt)
            end
        end
    end
end

local colClearLine = function(col,y,char)
    local cbg,ctxt,cx,cy = term.getBackgroundColor(), term.getTextColor(), term.getCursorPos()
    local scr_x,scr_y = term.getSize()
    term.setCursorPos(1,y or cy)
    term.setBackgroundColor(col or cbg)
    term.write((char or " "):rep(scr_x))
    term.setBackgroundColor(cbg)
    term.setTextColor(ctxt)
    term.setCursorPos(cx,cy)
end

local prettyPrint = function(left,right)
    local ctxt = term.getTextColor()
    term.setTextColor(term.isColor() and colors.yellow or colors.lightGray)
    write(left)
    term.setTextColor(ctxt)
    print(right)
end

local displayData = function()
    while true do
        term.clear()
        term.setCursorPos(1,1)
        colClearLine(colors.gray)
        prettyPrint("\nFuel: ",turtle.getFuelLevel())
        prettyPrint("X/Y/Z: ",tew.x.."/"..tew.y.."/"..tew.z)
        prettyPrint("Direction: ",tew.direction.." ("..directionNames[tew.direction]..")")
        prettyPrint("Requests: ",requests)
        colClearLine(colors.gray)
        print("\nPress 'X' to exit.")
        sleep(0)
    end
end

local displayHelp = function()
    local data = [[
Turtle GPS System (TPS)
by LDDestroier/EldidiStroyrr
 Place a chest down, and fill it with fuel.
 Place the turtle down (you did), and specify its own coordinates ('1') and the chest coordinates ('2').
 Start!]]
    print(data)
    sleep(0.1)
    os.pullEvent("key")
end

--[[local t = peripheral.find("turtle")  --this was for an easier setup with a specific pattern
if t then
    t.turnOn()
    tew.turnRight()
    tew.forward(2)
    tew.turnRight()
end--]]

local okaythen = false
while not okaythen do
    term.clear()
    term.setCursorPos(1,1)
    print()
    print("Push '1' to change coordinates...")
    print("Push '2' to change chest coordinates...")
    print("Push 'X' to cancel...")
    print("Push 'Spacebar' to start immediately...")
    local _x,_y = term.getCursorPos()
    local buttmode = 0
    local res = parallel.waitForAny(function()
        while true do
            local _,char = os.pullEvent("char")
            if char:lower() == "1" then
                buttmode = 1
                return
            elseif char:lower() == "2" then
                buttmode = 2
                return
            elseif char:lower() == " " then
                okaythen = true
                return
            elseif char:lower() == "x" then
                buttmode = -1
                return
            end
        end
    end,function()
        for a = 1, 3*10 do
            term.setCursorPos(_x,_y)
            term.write("Starting in "..(3-(a/10)).." seconds...")
            sleep(0.1)
        end
    end)

    if res == 1 then
        term.clear()
        term.setCursorPos(1,1)
        if buttmode == 1 then
            print("Turtle position input.")
            colClearLine(colors.white)
            write("\nX: ")
            tew.x = tonumber(read()) or tew.x
            write("Y: ")
            tew.y = tonumber(read()) or tew.y
            write("Z: ")
            tew.z = tonumber(read()) or tew.z
            print("Direction (F3 -> 'f'): ")
            for k,v in pairs(directionNames) do
                print(" "..k.." = '"..v.."'")
            end
            write(">")
            tew.direction = tonumber(read()) or tew.direction
            tps(true)
        elseif buttmode == 2 then
            print("Refuel Chest input.")
            colClearLine(colors.white)
            write("\nChest X: ")
            chestX = tonumber(read()) or chestX
            write("Chest Y: ")
            chestY = tonumber(read()) or chestY
            write("Chest Z: ")
            chestZ = tonumber(read()) or chestZ
            tps(true)
        elseif buttmode == -1 then
            print("Cancelled.")
            error()
        end
    else
        okaythen = true
    end
end

parallel.waitForAny(handleRequests,doTurtleMove,displayData) --,sendRequests) --everything's okay, then

term.setCursorPos(1,scr_y-2)
print("Thank you for using TPS!")
sleep(0)