Dataflow/FBP engine sketch in Objective-C

cocoaflow-engine-sketch.m

#include <Foundation/Foundation.h>
#include <stdio.h>
#include <objc/objc.h>

/*
TODO: Implement addNode,connect,addInitial for building network incrementally
TODO: Implement a component factory, to instantiate component from string name
TODO: Implement parsing of FBP .json format, build network from this
TODO: Implement queing of messages and asyncronous delicivery
*/


// Packet
typedef enum {
    kPacketData,
    kPacketBracketStart,
    kPacketBracketEnd
} PacketType;


@interface Packet : NSObject
{
  PacketType type;
  //id data;
  NSInteger integer;
}
@property (nonatomic) NSInteger integer;
@end

// Component
@protocol ComponentProtocol <NSObject>

- (void)process: (Packet *)packet onPort:(NSString *)portName;
- (void)send: (Packet *)packet onPort:(NSString *)portName;

@end

@class Network;

@interface Component : NSObject <ComponentProtocol>
{
  id data;
  Network *_network;
}
@end


@interface Network : NSObject
{
    NSDictionary *nodes;
    NSDictionary *connections;
}
- (void)_sendPacket: (Packet *)packet from: (Component *)srcNode outPort: (NSString *)srcPort;
@end



@implementation Packet
@synthesize integer;
@end


@implementation Component

- (id)init: (Network *)net {
    self = [super init];
    if (self != nil) {
        self->_network = net;
    }
    return self;
}

- (void)process: (Packet *)packet onPort:(NSString *)portName {
    NSLog(@"ERRROR: Component::process() not implememted");
}

- (void)send: (Packet *)packet onPort:(NSString *)portName {
   [_network _sendPacket: packet from: self outPort: portName];
}
@end


@interface AddOneComponent : Component
@end
@implementation AddOneComponent
- (void)process: (Packet *)packet onPort:(NSString *)portName {
    NSLog(@"AddOneComponent process");
    Packet *new = [[Packet alloc] init];
    new.integer = (packet.integer)+1;
    [self send: new onPort: @"out"];
}
@end


// Network
@implementation Network

- (id)init {
    self = [super init];
    if (self != nil) {
        NSLog(@"Network init");

        self->nodes = [NSDictionary dictionaryWithObjectsAndKeys:
                 [[AddOneComponent alloc] init: self], @"first",
                 [[AddOneComponent alloc] init: self], @"second",
                 [[AddOneComponent alloc] init: self], @"third",
                 nil
        ];

        // node:port
        self->connections = [NSDictionary dictionaryWithObjectsAndKeys:
                 @"second:in", @"first:out",
                 @"third:in", @"second:out",
                 nil
        ];

        Packet *iip = [[Packet alloc] init];
        iip.integer = 11;
        [(Component *)([self->nodes objectForKey: @"first"]) process : iip onPort: @"in"];
        NSLog(@"Network init complete");
    }
    return self;
}

- (void)_sendPacket: (Packet *)packet from: (Component *)srcNode outPort: (NSString *)srcPort
{
    NSLog(@"%d", packet.integer);
    NSArray *keys = [self->nodes allKeysForObject: srcNode];
    if ([keys count] == 1) {
        NSString *srcNodeId = (NSString *)[keys objectAtIndex: 0];
        NSString *srcConn = [srcNodeId stringByAppendingString: @":out"];
        NSString *tgtConn = [self->connections objectForKey: srcConn];

        NSArray *tokens = [tgtConn componentsSeparatedByString:@":"];
        if ([tokens count] == 2) {
            Component *tgtNode = (Component *)[self->nodes objectForKey: [tokens objectAtIndex: 0]];
            [tgtNode process: packet onPort: [tokens objectAtIndex: 1]];
        } else {
            NSLog(@"ERROR: expected node:port");
        }
    } else {
        NSLog(@"ERROR: expected unique identifier for component");    
    }
}

/*
- (void)addNode: (NSString *)name withComponent: (Component *) component
{

}

- (void)connect: (NSString *)srcNode outPort: (NSString *)srcPort
                 toNode: (NSString *)tgtNode inPort: (NSString *)tgtPort
{
}

- (void)setInitial: (Packet *)packet toNode: (NSString *)tgtNode inPort: (NSString *)tgtPort
{
}
*/

@end


int main(void)
{ 
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];

    Network *net = [[Network alloc] init];

    [pool release];
    return(0);
}