CC: Treefarm - gps.lua

-- DIRECTIONS
north = "n"
south = "s"
east = "e"
west = "w"
up = "u"
down = "d"

-- TURTLE POSITION
absPos = {} --{x=0,y=0,z=0,dir=north}
homePos = {}

-- gets all global variables
function init( global )
    setfenv(1,global)
    -- gps functions included in CC
    gpsModule = _G["gps".._G.oldAPISyntax]
end

function isDir( dir )
    if dir == north
    or dir == south
    or dir == east
    or dir == west
    or dir == up
    or dir == down
    then
        return true
    else
        return false
    end
end

function getDirectionOffset( dir )
    local x,y,z = 0,0,0

    if dir == up then y = y + 1 end
    if dir == down then y = y - 1 end

    if dir == south then z = z + 1 end
    if dir == north then z = z - 1 end

    if dir == east then x = x + 1 end
    if dir == west then x = x - 1 end

    return x,y,z
end

function getPosition( offset,dir )
    local ox,oy,oz = 0,0,0
    local x,y,z = absPos.x,absPos.y,absPos.z

    if type(offset) ~= "number" then
        offset = 0
    end

    if type(dir) == "string" then
        ox,oy,oz = getDirectionOffset(dir)
    end

    x = x + ox*offset
    y = y + oy*offset
    z = z + oz*offset

    return x,y,z,absPos.dir
end

function setPosition( x,y,z,dir )
    absPos.x = x or absPos.x
    absPos.y = y or absPos.y
    absPos.z = z or absPos.z
    absPos.dir = dir or absPos.dir
end

function addPosition( x,y,z )
    absPos.x = absPos.x + (x or 0)
    absPos.y = absPos.y + (y or 0)
    absPos.z = absPos.z + (z or 0)
end

function getHome( offset,dir )
    local ox,oy,oz = 0,0,0
    local x,y,z = homePos.x,homePos.y,homePos.z

    if type(offset) ~= "number" then
        offset = 0
    end

    if type(dir) == "string" then
        ox,oy,oz = getDirectionOffset(dir)
    end

    x = x + ox*offset
    y = y + oy*offset
    z = z + oz*offset

    return x,y,z,homePos.dir
end

function setHome( x,y,z,dir )
    homePos.x = x or homePos.x
    homePos.y = y or homePos.y
    homePos.z = z or homePos.z
    homePos.dir = dir or homePos.dir
end

function dirToValue( dir )
    if dir == south then return 0 end
    if dir == west then return 1 end
    if dir == north then return 2 end
    if dir == east then return 3 end
    if dir == up then return math.huge end
    if dir == down then return -math.huge end
end

function valueToDir( value )
    if value == 0 then return south end
    if value == 1 then return west end
    if value == 2 then return north end
    if value == 3 then return east end
    if value == math.huge then return up end
    if value == -math.huge then return down end
end

function turnRight( times )
    if type(times)~="number" then times = 1 end
    if times<1 then times = 1 end
    if times%1~=0 then times = math.floor(times) end

    for count = 1,times do
        -- turn the dir var
        absPos.dir = valueToDir(((dirToValue(absPos.dir) or 0)+1)%4)

        turtle.turnRight()
    end
end

function turnLeft( times )
    if type(times)~="number" then times = 1 end
    if times<1 then times = 1 end
    if times%1~=0 then times = math.floor(times) end

    for count = 1,times do
        -- turn the dir var
        absPos.dir = valueToDir(((dirToValue(absPos.dir) or 0)+3)%4)

        turtle.turnLeft()
    end
end

-- locate where the turtle is in the real world by using the built in gps system
-- requires the turtle to have a wireless modem on the right side
function autoSetPosition()
    print("gps start")
    if peripheral.getType("right")~="modem" then return false end
    rednet.open("right")

    print("gps step 1")

    local x1,y1,z1 = gpsModule.locate()print("gps step 2")
    if type(x1)~="number" or type(y1)~="number" or type(z1)~="number" then return false end

    local dir = "unknown"

    local try = 0
    while not turtle.forward() do
        try = try + 1
        turtle.turnRight()
        if try == 4 then return false end
    end
    print("gps step 3")

    local x2,y2,z2 = gpsModule.locate()print("gps step 4")
    if type(x2)~="number" or type(y2)~="number" or type(z2)~="number" then return false end

    if x2 == x1 + 1 then dir = east end
    if x2 == x1 - 1 then dir = west end
    if z2 == z1 + 1 then dir = south end
    if z2 == z1 - 1 then dir = north end

    if dir == "unknown" then
        return false
    end
    print("gps step 5")
    setPosition(x2,y2,z2,dir)
    print("gps step final")
    return true
end

function getFacing()
    return absPos.dir
end

function face( dir )
    -- stop if dir is not a valid direction
    if not isDir(dir) then return end
    if dir == up then return end
    if dir == down then return end

    --
    if type(absPos.dir) ~= "string" then
        locate()
    end

    local wantedValue = dirToValue(dir)
    local currentValue = dirToValue(absPos.dir)

    -- continue looping until you face the desired direction
    while currentValue ~= wantedValue do
        if (currentValue+1)%4 == wantedValue then
            -- disered direction is to the right
            turnRight()
        elseif (currentValue+3)%4 == wantedValue then
            -- disered direction is to the left
            turnLeft()
        else
            -- desired direction is behind us, so turn either right or left
            if math.random(0,1) == 1 then
                turnRight()
            else
                turnLeft()
            end
        end

        -- update currentValue variable
        currentValue = dirToValue(absPos.dir)
    end
end

function moveUp( times,killMobs,destroyBlocks )
    if type(times)~="number" then times = 1 end
    --if times<1 then times = 1 end
    if times%1~=0 then times = math.floor(times) end

    if type(absPos.dir) ~= "string" then
        autoSetPosition()
    end

    for count = 1,times do
        while not turtle.up() do
            if not destroyBlocks then return false end
            dig.up(killMobs,destroyBlocks)
        end
        addPosition(_,1)
    end
    return true
end

function moveDown( times,killMobs,destroyBlocks )
    if type(times)~="number" then times = 1 end
    --if times<1 then times = 1 end
    if times%1~=0 then times = math.floor(times) end

    if type(absPos.dir) ~= "string" then
        autoSetPosition()
    end

    for count = 1,times do
        while not turtle.down() do
            if not destroyBlocks then return false end
            dig.down(killMobs,destroyBlocks)
        end
        addPosition(_,-1)
    end
    return true
end

function moveForward( times,killMobs,destroyBlocks )
    if type(times)~="number" then times = 1 end
    --if times<1 then times = 1 end
    if times%1~=0 then times = math.floor(times) end

    if type(absPos.dir) ~= "string" then
        autoSetPosition()
    end

    for count = 1,times do
        while not turtle.forward() do
            if destroyBlocks then
                dig.forward(killMobs,destroyBlocks)
            else
                return false
            end
        end
        addPosition(getDirectionOffset(absPos.dir))
    end
    return true
end

function goto( x,y,z,dir,killMobs,destroyBlocks )
    --print("goto function: x="..tostring(x).." y="..tostring(y).." z="..tostring(z).." killMobs="..tostring(killMobs).." destroyBlocks="..tostring(destroyBlocks))
    if type(x)~="number" then x=absPos.x end
    if type(y)~="number" then y=absPos.y end
    if type(z)~="number" then z=absPos.z end
    x=math.floor(x) y=math.floor(y) z=math.floor(z)
    if type(killMobs)~="boolean" then killMobs=false end
    if type(destroyBlocks)~="boolean" then destroyBlocks=false end

    if type(absPos.dir) ~= "string" then
        autoSetPosition()
    end

    while absPos.x~=x or absPos.y~=y or absPos.z~=z do
        -- current location
        local cx,cy,cz = getPosition()

        -- y
        if y~=cy then
            for count = math.min(cy,y),math.max(cy,y)-1 do
                if y>cy then
                    if not moveUp(_,killMobs,destroyBlocks) then break end
                elseif y<cy then
                    if not moveDown(_,killMobs,destroyBlocks) then break end
                end
            end
        end

        -- x
        if x~=cx then
            for count = math.min(cx,x),math.max(cx,x)-1 do
                if x>cx then -- x increasing
                    face(east)
                elseif x<cx then -- x decreasing
                    face(west)
                end
                if not moveForward(_,killMobs,destroyBlocks) then break end
            end
        end

        -- z
        if z~=cz then
            for count = math.min(cz,z),math.max(cz,z)-1 do
                if z>cz then -- z increasing
                    face(south)
                elseif z<cz then -- z decreasing
                    face(north)
                end
                if not moveForward(_,killMobs,destroyBlocks) then break end
            end
        end
    end

    if isDir(dir) then
        face(dir)
    end
end