blob: 15e16ab6432169e1e7f79eab0be09fd82de199f4 [file] [log] [blame] [raw]
package li.cil.oc.api
import li.cil.oc.api.detail.NetworkAPI
import li.cil.oc.api.network.Node
import net.minecraft.world.World
/**
* Interface for interacting with component networks.
* <p/>
* Computers and components form ad-hoc "networks" when placed next to each
* other. They allow computers to communicate with the components attached to
* them, as well as components to send signals to computers they are attached to
* (and even among each other).
* <p/>
* Whenever a networkable component is placed, it should first scan its
* neighbors to see if a network already exists. If so, it should join that
* network. If multiple different networks are adjacent it should join one and
* then merge it with the other(s). If no networks exist, it should create a new
* one. All this logic is provided by `Network.joinOrCreateNetwork`.
* <p/>
* Note that for network nodes implemented in `TileEntities` adding and
* removal is automatically provided on chunk load and unload. When a block is
* placed or broken you will have to implement this logic yourself (i.e. call
* `Network.joinOrCreateNetwork` in `onBlockAdded` and `Network.remove` in
* `breakBlock`.
* <p/>
* All other kinds of nodes have to be managed manually. See `Node`.
* <p/>
* There are a couple of system messages to be aware of. These are all sent by
* the network manager itself:
* <ul>
* <li>`system.connect` is generated when a node is added to the network,
* with the added node as the sender. This will also be sent to the nodes of
* the other network, when a network merges with another one (both ways).</li>
* <li>`system.disconnect` is generated when a node is removed from the
* network, with the removed node as the sender. This will also be sent to the
* nodes of the other network(s), when a network is split (all pairs).</li>
* </ul>
* <p/>
* IMPORTANT: do *not* implement this interface yourself and create
* instances of your own network implementation; this will lead to
* incompatibilities with the built-in network implementation (which can only
* merge with other networks of its own type). Always use the methods provided
* in `Network` to create and join networks.
*/
trait Network {
/**
* Adds a new node connection in the network.
* <p/>
* This is used by nodes to join an existing network. At least one of the two
* nodes must already be in the network. If one of the nodes is not yet in the
* network, it will be added to the network. If both nodes are already in the
* network only the connection between the two nodes is added. If one of the
* nodes is not in this network but in another network, the networks will be
* merged.
* <p/>
* This way of adding nodes is used to build an internal graph to allow
* properly splitting networks when nodes are removed.
*
* @param nodeA the first node.
* @param nodeB the second node.
* @return true if a new connection between the two nodes was added; false if
* the connection already existed.
* @throws IllegalArgumentException if neither node is in this network.
*/
def connect(nodeA: Node, nodeB: Node): Boolean
/**
* Removes a node connection in the network.
* <p/>
* Both nodes must be part of this network.
* <p/>
* This can be useful for cutting connections that depend on some condition
* that does not involve the nodes' actual existence in the network, such as
* the distance between two nodes, for example (think access points of a
* wireless network).
*
* @param nodeA the first node.
* @param nodeB the second node.
* @return true if the connection was cut; false if there was none.
* @throws IllegalArgumentException if the nodes are not in this network.
*/
def disconnect(nodeA: Node, nodeB: Node): Boolean
/**
* Removes a node from the network.
* <p/>
* This should be called by nodes when they are destroyed (e.g. `breakBlock`)
* or unloaded. Removing the node can lead to one or more new networks if it
* was the a bridge node, i.e. the only node connecting the resulting
* networks.
*
* @param node the node to remove from the network.
* @return true if the node was removed; false if it wasn't in the network.
*/
def remove(node: Node): Boolean
// ----------------------------------------------------------------------- //
/**
* Get the network node with the specified address.
*
* @param address the address of the node to get.
* @return the node with that address.
*/
def node(address: String): Option[Node]
/**
* The list of all addressed nodes in this network.
*
* @return the list of nodes in this network.
*/
def nodes: Iterable[Node]
/**
* The list of addressed nodes in the network visible to the specified node.
* <p/>
* This does *not* include nodes with a visibility of `Visibility.None` or
* a visibility of `Visibility.Neighbors` when there is no direct connection
* between that node and the reference node.
* <p/>
* This does *not* include the node itself.
* <p/>
* This can be useful when performing a delayed initialization of a node.
* For example, computers will use this when starting up to generate
* `component_added` signals for all visible nodes in the network.
*
* @param reference the node to get the visible other nodes for.
* @return the nodes visible to the specified node.
*/
def nodes(reference: Node): Iterable[Node]
/**
* The list of nodes the specified node is directly connected to.
* <p/>
* This *does* include nodes with a visibility of `Visibility.None`.
* <p/>
* This does *not* include the node itself.
* <p/>
* This can be used to verify arguments for components that should only work
* for other components that are directly connected to them, for example.
*
* @param node the node to get the neighbors for.
* @return a list of nodes the node is directly connect to.
* @throws IllegalArgumentException if the specified node is not in this network.
*/
def neighbors(node: Node): Iterable[Node]
// ----------------------------------------------------------------------- //
/**
* Sends a message to the node with the specified address.
* <p/>
* If the target node with that address has a visibility of `Visibility.None`
* the message will *not* be delivered to that node. If the target node with
* that address has a visibility of `Visibility.Neighbors` and the source
* node is not directly connected to the target the message will *not* be
* delivered to that node.
* <p/>
* Messages should have a unique name to allow differentiating them when
* handling them in a network node. For example, computers will try to parse
* messages named `computer.signal` by converting the message data to a
* signal and inject that signal into the Lua VM, so no message not used for
* this purpose should be named `computer.signal`.
* <p/>
* Note that message handlers may also return results. In this case that
* result will be returned from this function. In the case that there are
* more than one target node (shared addresses, should not happen, but may if
* a node implementation decides to ignore this rule) the last result that
* was not `None` will be returned, or `None` if all results were `None`.
*
* @param source the node that sends the message.
* @param target the id of the node to send the message to.
* @param name the name of the message.
* @param data the message to send.
* @return the result of the message being handled, if any.
* @throws IllegalArgumentException if the source node is not in this network.
*/
def sendToAddress(source: Node, target: String, name: String, data: Any*): Option[Array[Any]]
/**
* Sends a message to all addressed, visible neighbors of the source node.
* <p/>
* Targets are determined using `neighbors(source)` and additionally filtered
* for visibility (so that nodes with `Visibility.None` are ignored).
* <p/>
* Messages should have a unique name to allow differentiating them when
* handling them in a network node. For example, computers will try to parse
* messages named `computer.signal` by converting the message data to a
* signal and inject that signal into the Lua VM, so no message not used for
* this purpose should be named `computer.signal`.
*
* @param source the node that sends the message.
* @param name the name of the message.
* @param data the message to send.
* @return the result of the message being handled, if any.
* @throws IllegalArgumentException if the source node is not in this network.
* @see `neighbors`
*/
def sendToNeighbors(source: Node, name: String, data: Any*): Option[Array[Any]]
/**
* Sends a message to all addressed nodes visible to the source node.
* <p/>
* Targets are determined using `nodes(source)`.
* <p/>
* Messages should have a unique name to allow differentiating them when
* handling them in a network node. For example, computers will try to parse
* messages named `computer.signal` by converting the message data to a
* signal and inject that signal into the Lua VM, so no message not used for
* this purpose should be named `computer.signal`.
*
* @param source the node that sends the message.
* @param data the message to send.
* @return the result of the message being handled, if any.
* @throws IllegalArgumentException if the source node is not in this network.
* @see `nodes`
*/
def sendToVisible(source: Node, name: String, data: Any*): Option[Array[Any]]
}
object Network extends NetworkAPI {
/**
* Tries to add a tile entity network node at the specified coordinates to
* adjacent networks.
*
* @param world the world the tile entity lives in.
* @param x the X coordinate of the tile entity.
* @param y the Y coordinate of the tile entity.
* @param z the Z coordinate of the tile entity.
*/
def joinOrCreateNetwork(world: World, x: Int, y: Int, z: Int) =
instance.foreach(_.joinOrCreateNetwork(world, x, y, z))
// ----------------------------------------------------------------------- //
/** Initialized in pre-init. */
private[oc] var instance: Option[NetworkAPI] = None
}