computercraft test script

-- computercraft

-- init
turtle.refuel()
rednet.open("left")

-- utility functions

function determineDirection()
    xc, yc, zc = gps.locate()
    turtle.dig()
    turtle.forward()
    xc2, yc2, zc2 = gps.locate()
    turtle.back()
    -- based on which coordinate changed we can calculate which direction the turtle is facing
    if xc - xc2 == -1 then
        return "east"
    end
    if xc - xc2 == 1 then
        return "west"
    end
    if zc - zc2 == -1 then
        return "south"
    end
    if zc - zc2 == 1 then
        return "north"
    end
    return "none"
end

function turtle.turnAround()
    turtle.turnLeft()
    turtle.turnLeft()
end

function sgn(num)
    if num > 0 then
        return 1
    end
    if num < 0 then
        return -1
    end
    return 0
end

function ensureFacingNorth()
    i = 0
    ::tryAgain::
    direction = determineDirection()
    -- make turtle always face north for movements
    if direction == "east" then
        turtle.turnLeft()
    elseif direction == "west" then
        turtle.turnRight()
    elseif direction == "south" then
        turtle.turnAround()
    elseif direction ~= "north" then
        if i ~= 4 then
            turtle.turnRight()
            i = i + 1
            goto tryAgain
        end
    end
end

function mineAllAroundEmergency()
    for i=1,4 do
        turtle.turnLeft()
        turtle.dig()
    end
    turtle.digUp()
    turtle.digDown()
end

function gotoPos(x, y, z, try)
    -- get turtle pos from gps
    xpos, ypos, zpos = gps.locate()
    ensureFacingNorth()
    turtle.turnRight()
    ::toPos::
    for i=1, math.abs(x-xpos) do
        if sgn(x-xpos) == 0 then
            break
        elseif sgn(x-xpos) == 1 then
            turtle.dig()
            turtle.forward()
        elseif sgn(x-xpos) == -1 then
            turtle.turnAround()
            turtle.dig()
            turtle.turnAround()
            turtle.back()
        end
    end
    turtle.turnLeft()
    if try >= 2 then
        mineAllAroundEmergency() --attempt to get unstuck
    end
    if try >= 2 and try <= 10 then
        turtle.up()
    end
    for i=1, math.abs(z-zpos) do
        if sgn(z-zpos) == 0 then
            break
        elseif sgn(z-zpos) == 1 then
            turtle.dig()
            turtle.forward()
        elseif sgn(z-zpos) == -1 then
            turtle.turnAround()
            turtle.dig()
            turtle.turnAround()
            turtle.back()
        end
    end
    for i=1, math.abs(y-ypos) do
        if sgn(y-ypos) == 0 then
            break
        elseif sgn(y-ypos) == 1 then
            turtle.digUp()
            turtle.up()
        elseif sgn(y-ypos) == -1 then
            turtle.digDown()
            turtle.down()
        end
    end
    -- get turtle pos from gps again
    xpos, ypos, zpos = gps.locate()
    xdiff = x - xpos
    ydiff = y - ypos
    zdiff = z - zpos
    -- if we aren't at target point then go back to trying to get there until we get there
    if not (xdiff == 0 and ydiff == 0 and zdiff == 0) then
        print("We are not at target point "..x.." "..y.." "..z..". Why?!?!")
        ensureFacingNorth()
        gotoPos(x, y, z, try + 1)
    end
    -- if we are at the target point then finish and end function
end

function splitBySpace(string)
    temp = {}
    i2 = 1
    for i in string.gmatch(string, "%S+") do
        temp[i2] = i
        i2 = i2 + 1
    end
    return temp
end

function faceDirectionAssumingNorth(directiona)
    if directiona == "east" then
        turtle.turnLeft()
    elseif directiona == "west" then
        turtle.turnRight()
    elseif directiona == "south" then
        turtle.turnAround()
    elseif directiona ~= "north" then
        error("Invalid direction")
    end
end

function depositAndRefuel(homex, homey, homez, minestartx, minestarty, minestartz, facing)
    curx, cury, curz = gps.locate()
    gotoPos(minestartx, homey, minestartz, 1)
    -- we are now on the surface (or should be)
    gotoPos(homex, homey, homez, 1)
    -- we are also guaranteed to be facing north after movement, so deposit in chest south of turtle
    turtle.turnAround()
    -- deposit everything in the chest
    for i=1, 16 do
        turtle.select(i)
        turtle.drop()
    end
    turtle.turnAround()
    -- we expect to have a fuel chest above the home point, so get a stack from the fuel chest
    turtle.suckUp()
    turtle.refuel()
    -- return to what we were doing
    gotoPos(minestartx, homey, minestartz, 1)
    -- travel down the mineshaft
    gotoPos(minestartx, minestarty, minestartz, 1)
    -- we are now back in the layer, go to where we were before this function was called
    gotoPos(curx, cury, curz, 1)
    -- face where we were before this function was called
    faceDirectionAssumingNorth(facing)
end
function goHome(homex, homey, homez, minestartx, minestarty, minestartz)
    gotoPos(minestartx, homey, minestartz, 1)
    gotoPos(homex, homey, homez, 1)
    turtle.turnAround()
end

function isInventoryFull()
    full = 0
    for i=1, 16 do
        turtle.select(i)
        if turtle.getItemCount() > 0 then
            full = full + 1
        end
    end
    turtle.select(1)
    return full == 16
end

-- main

homex, homey, homez = gps.locate()
while true do
    -- standby to recieve command
    sender, message = rednet.receive()
    if string.find(message, "GOTO") ~= nil then
        message = splitBySpace(message)
        rednet.send(sender, "ACK")
        gotoPos(tonumber(message[2]), tonumber(message[3]), tonumber(message[4]), 1)
    end
    if string.find(message, "MINE") ~= nil then
        message = splitBySpace(message)
        rednet.send(sender, "ACK") -- since i don't get the ACK from the turtle, the bug must be occuring before here
        -- message format: "MINE -4220 64 3433 -4110 50 3333"
        x1 = message[2]
        y1 = message[3]
        z1 = message[4]
        x2 = message[5]
        y2 = message[6]
        z2 = message[7]
        startx, starty, startz = gps.locate()
        -- depositAndRefuel(homex, homey, homez, startx, starty, startz, "north")
        -- everything in y layers
        for y=1, math.abs(y1-y2) do
            gotoPos(math.min(x1, x2), math.min(y1, y2) + y - 1, math.max(z1, z2), 1)
            switch = true
            facing = "north"
            -- everything in x layer
            for x=1, math.abs(x1-x2) + 1 do
                -- everything in z line
                for z=1, math.abs(z1-z2) do
                    turtle.dig()
                    turtle.forward()
                end
                if switch then
                    turtle.turnRight()
                    turtle.dig()
                    turtle.forward()
                    turtle.turnRight()
                    facing = "south"
                else
                    turtle.turnLeft()
                    turtle.dig()
                    turtle.forward()
                    turtle.turnLeft()
                    facing = "north"
                end
                if isInventoryFull() or turtle.getFuelLevel() <= 200 then
                    depositAndRefuel(homex, homey, homez, math.min(x1, x2), math.min(y1, y2) + math.abs(y1-y2) - 1, math.max(z1, z2), facing)
                end
                switch = not switch
            end
            turtle.dig()
        end
        goHome(homex, homey, homez, math.min(x1, x2), math.min(y1, y2) + math.abs(y1-y2) - 1, math.max(z1, z2))
        turtle.turnAround()
    end
end