ReactiveHell

ReactiveHell.json

Vehicle:
{  
  "vehicle":{
    "id":1,
    "name":"AlfaRomeo",
    "chassi":[12, 13, 27, 24],
    "wings":[3, 250, 1],
    "engine":[29],
    "headlights":[201],
    "profile":901
  }
}

Profiles:

{  
  "profile":{
    "id":901,
    "chassi": {
        // bonus - no id :)
        "price":1,
        "param1":"value1"
    },
    "wings": {
        // bonus - no id :)
        "price":100,
        "param2":"value2"
    },
    "engine": {
        // bonus - no id :)
        "price":3,
        "param3":"value3"
    },
    "headlights": {
        // bonus - no id :)
        "price":5,
        "param4":"value4"
    }
  }
}

ReactiveHell.m

- (RACSignal *)fetchModules:(NSDictionary<NSString *, NSString *> *)moduleIDsToProfileIDsDictionary
                 forVehicle:(NSString *)vehicle
                 moduleType:(VehicleModule)moduleType {
    @weakify(self);
    return [[[RACSignal merge:[moduleIDsToProfileIDsDictionary map:^RACSignal *(NSString *moduleID, NSString *profileID) {
        @strongify(self);
        return [[self fetchProfileForID:profileID] combineLatestWith:[RACSignal return:moduleID]];
    }]] collect] map:^NSArray<ModuleBase *> *(NSArray<RACTuple *> *profiles) {
        return [[[profiles map:^NSArray<ModuleBase*> *(RACTuple *profileTuple) {
            RACTupleUnpack(NSDictionary *profileDict, NSString *moduleID) = profileTuple;
            return [profileDict map:^ModuleBase *(NSString *key, VehicleProfile *profile) {
                ModuleBase *module = nil;
                switch (moduleType) {
                    case VehicleModuleHeadlights:
                        module = profile.headlights;
                        break;
                    case VehicleModuleEngine:
                        module = profile.engine;
                        break;
                    case VehicleModuleWings:
                        module = profile.wings;
                        break;
                    case VehicleModuleChassi:
                        module = profile.chassi;
                        break;
                    case VehicleModuleUndefinded:
                        NSAssert(NO, @"undefined module type");
                }
                module.moduleID = moduleID;
                return module;
            }];
        }] flatten] sortedArrayUsingDescriptors:@[[NSSortDescriptor sortDescriptorWithKey:@"price" ascending:YES]]];
    }];
}