ComputerCraftLib.lua

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-- Generic LUA library for ComputerCraft
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-- Written by Shikifuyin
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-- Includes

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-- Global definitions

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-- File I/O
File = {
        -- Constants

        -- Members

        -- Internal members/methods

        -- Methods
    Exists = function( strName )
        return fs.exists( strName )
    end,

    LoadVar = function( strName )
        hFile = fs.open( strName, "r" )
        hValue = hFile.read()
        hFile.close()
        return hValue
    end,
    SaveVar = function( strName, hValue )
        hFile = fs.open( strName, "w" )
        hFile.write( hValue )
        hFile.close()
    end
}

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-- Turtles
TurtleInterfaces = {
        -- Methods
    -- GetModem : Retrieve face with modem interface
    GetModem = function()
        for X, strFacet in pairs(rs.getSides()) do
            if ( peripheral.getType(strFacet) == "modem" ) then
                return strFacet
            end
        end
        return nil
    end
}

TurtleController = {
        -- Constants
    MOVE_XYZ = 0,
    MOVE_XZY = 1,
    MOVE_YXZ = 2,
    MOVE_YZX = 3,
    MOVE_ZXY = 4,
    MOVE_ZYX = 5,

    ORIENTATION_NORTH = 0,
    ORIENTATION_EAST  = 1,
    ORIENTATION_SOUTH = 2,
    ORIENTATION_WEST  = 3,

        -- Members
    Position = { X = 0, Y = 0, Z = 0 }, -- Position relative to last set origin
    Orientation = ORIENTATION_NORTH,    -- Orientation relative to last set origin

        -- Internal members/methods
    _Internal = {
        _Move_X = function( iDX, iOrientation )
            local iAmountX = abs( iDX )
            if ( iDX < 0 ) then -- Move backward
                turtle.turnRight()
                turtle.turnRight()
                iOrientation = iOrientation + 2
                while ( iOrientation > 3 ) do iOrientation = iOrientation - 4 end
                for i = 1, iAmountX do turtle.forward() end
            elseif ( iDX > 0 ) then -- Move forward
                for i = 1, iAmountX do turtle.forward() end
            end
            return iOrientation
        end,
        _Move_Y = function( iDY, iOrientation )
            local iAmountY = abs( iDY )
            if ( iDY < 0 ) then -- Move left
                turtle.turnLeft()
                iOrientation = iOrientation - 1
                while ( iOrientation < 0 ) do iOrientation = iOrientation + 4 end
                for i = 1, iAmountY do turtle.forward() end
            elseif ( iDY > 0 ) then -- Move right
                turtle.turnRight()
                iOrientation = iOrientation + 1
                while ( iOrientation > 3 ) do iOrientation = iOrientation - 4 end
                for i = 1, iAmountY do turtle.forward() end
            end
            return iOrientation
        end,
        _Move_Z = function( iDZ )
            local iAmountZ = abs( iDZ )
            if ( iDZ < 0 ) then -- Move down
                for i = 1, iAmountZ do turtle.down() end
            elseif ( iDZ > 0 ) then -- Move up
                for i = 1, iAmountZ do turtle.up() end
            end
        end
    },

        -- Methods
    -- Constructor
    New = function( this, hObject )
        hObject = hObject or {}
        setmetatable( hObject, this )
        this.__index = this
        return hObject
    end,

    -- Refuel : Search inventory for fuel and use it if needed
    Refuel = function( this )
        for i = 1, 16 do
            if ( turtle.getFuelLevel() >= 1 ) then
                return
            end
            turtle.select( i )
            turtle.refuel()
            turtle.select( 1 )
        end
    end,

    -- SetOrigin : Sets current turtle's position & orientation as absolute origin
    SetOrigin = function( this )
        this.Position.X = 0
        this.Position.Y = 0
        this.Position.Z = 0
        this.Orientation = ORIENTATION_NORTH
    end,

    -- Turn : Rotates the turtle along Z axis
    -- iOrientation = Target orientation relative to current orientation (relative, default) or tracked orientation (absolute)
    -- bAbsolute    = Use origin-tracking system to specify absolute orientation else use relative orientation (default)
    Turn = function( this, iOrientation, bAbsolute )
        -- Default parameters
        bAbsolute = bAbsolute or false

        if ( bAbsolute ) then
            -- Clamp orientation value
            while ( iOrientation < 0 ) do iOrientation = iOrientation + 4 end
            while ( iOrientation > 3 ) do iOrientation = iOrientation - 4 end

            -- Absolute rotation case
            while ( this.Orientation > iOrientation ) do
                turtle.turnLeft()
                this.Orientation = this.Orientation - 1
            end
            while ( this.Orientation < iOrientation ) do
                turtle.turnRight()
                this.Orientation = this.Orientation + 1
            end
        else
            -- Clamp orientation value
            while ( iOrientation < -3 ) do iOrientation = iOrientation + 4 end
            while ( iOrientation > 3 ) do iOrientation = iOrientation - 4 end

            -- Relative rotation case
            while ( iOrientation < 0 ) do
                turtle.turnLeft()
                this.Orientation = this.Orientation - 1
                iOrientation = iOrientation + 1
            end
            while ( iOrientation > 0 ) do
                turtle.turnRight()
                this.Orientation = this.Orientation + 1
                iOrientation = iOrientation - 1
            end

            -- Clamp final value
            while ( this.Orientation < 0 ) do this.Orientation = this.Orientation + 4 end
            while ( this.Orientation > 3 ) do this.Orientation = this.Orientation - 4 end
        end
    end,

    -- Move : Moves the turtle.
    -- iX, iY, iZ       = Target position relative to current position (relative, default) or tracked origin (absolute)
    -- iAxisOrdering    = Use one of the above values to specify movement ordering (default = XYZ)
    -- bKeepOrientation = Restore pre-move orientation (no momentum) else use post-move orientation (keep momentum, default)
    -- bAbsolute        = Use origin-tracking system to specify absolute coordinates else use relative coordinates (default)
    Move = function( this, iX, iY, iZ, iAxisOrdering, bKeepOrientation, bAbsolute )
        -- Default parameters
        iAxisOrdering = iAxisOrdering or this.MOVE_XYZ
        bKeepOrientation = bKeepOrientation or false
        bAbsolute = bAbsolute or false

        -- Save initial orientation
        local iInitialOrientation = this.Orientation

        -- Absolute movement case
        if ( bAbsolute ) then
            iX = ( iX - this.Position.X )
            iY = ( iY - this.Position.Y )
            iZ = ( iZ - this.Position.Z )
        end

        -- Switch with axis ordering
        if ( iAxisOrdering == this.MOVE_XYZ ) then
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
            this._Internal._Move_Z( iZ )
        elseif ( iAxisOrdering == this.MOVE_XZY ) then
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
            this._Internal._Move_Z( iZ )
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
        elseif ( iAxisOrdering == this.MOVE_YXZ ) then
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
            this._Internal._Move_Z( iZ )
        elseif ( iAxisOrdering == this.MOVE_YZX ) then
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
            this._Internal._Move_Z( iZ )
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
        elseif ( iAxisOrdering == this.MOVE_ZXY ) then
            this._Internal._Move_Z( iZ )
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
        elseif ( iAxisOrdering == this.MOVE_ZYX ) then
            this._Internal._Move_Z( iZ )
            this.Orientation = this._Internal._Move_Y( iY, this.Orientation )
            this.Orientation = this._Internal._Move_X( iX, this.Orientation )
        end

        -- Correct orientation if asked to
        if ( bKeepOrientation ) then
            while ( this.Orientation > iInitialOrientation ) do
                turtle.turnLeft()
                this.Orientation = this.Orientation - 1
            end
            while ( this.Orientation < iInitialOrientation ) do
                turtle.turnRight()
                this.Orientation = this.Orientation + 1
            end
        end

        -- Update position
        this.Position.X = this.Position.X + iX
        this.Position.Y = this.Position.Y + iY
        this.Position.Z = this.Position.Z + iZ
    end
}