OOJSSystemInfo.m

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/*
 
OOJSSystemInfo.m
 
Oolite
Copyright (C) 2004-2013 Giles C Williams and contributors
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301, USA.
 
*/
 
#import "OOJSSystemInfo.h"
#import "OOJavaScriptEngine.h"
#import "PlayerEntityScriptMethods.h"
#import "Universe.h"
#import "OOJSVector.h"
#import "OOIsNumberLiteral.h"
#import "OOConstToString.h"
#import "OOSystemDescriptionManager.h"
#import "OOJSScript.h"
 
 
static JSObject *sSystemInfoPrototype;
static JSObject *sCachedSystemInfo;
static OOGalaxyID sCachedGalaxy;
static OOSystemID sCachedSystem;
 
 
static JSBool SystemInfoDeleteProperty(JSContext *context, JSObject *this, jsid propID, jsval *value);
static JSBool SystemInfoGetProperty(JSContext *context, JSObject *this, jsid propID, jsval *value);
static JSBool SystemInfoSetProperty(JSContext *context, JSObject *this, jsid propID, JSBool strict, jsval *value);
static void SystemInfoFinalize(JSContext *context, JSObject *this);
static JSBool SystemInfoEnumerate(JSContext *context, JSObject *this, JSIterateOp enumOp, jsval *state, jsid *idp);
 
static JSBool SystemInfoDistanceToSystem(JSContext *context, uintN argc, jsval *vp);
static JSBool SystemInfoRouteToSystem(JSContext *context, uintN argc, jsval *vp);
static JSBool SystemInfoSamplePrice(JSContext *context, uintN argc, jsval *vp);
static JSBool SystemInfoSetPropertyMethod(JSContext *context, uintN argc, jsval *vp);
 
static JSBool SystemInfoStaticSetInterstellarProperty(JSContext *context, uintN argc, jsval *vp);
static JSBool SystemInfoStaticFilteredSystems(JSContext *context, uintN argc, jsval *vp);
 
 
static JSClass sSystemInfoClass =
{
    "SystemInfo",
    JSCLASS_HAS_PRIVATE | JSCLASS_NEW_ENUMERATE,
    
    JS_PropertyStub,
    SystemInfoDeleteProperty,
    SystemInfoGetProperty,
    SystemInfoSetProperty,
    (JSEnumerateOp)SystemInfoEnumerate,
    JS_ResolveStub,
    JS_ConvertStub,
    SystemInfoFinalize,
    JSCLASS_NO_OPTIONAL_MEMBERS
};
 
 
enum
{
    // Property IDs
    kSystemInfo_coordinates,    // system coordinates (in LY), Vector3D (with z = 0), read-only
    kSystemInfo_internalCoordinates,    // system coordinates (unscaled), Vector3D (with z = 0), read-only
    kSystemInfo_galaxyID,       // galaxy number, integer, read-only
    kSystemInfo_systemID        // system number, integer, read-only
};
 
 
static JSPropertySpec sSystemInfoProperties[] =
{
    // JS name                  ID                                  flags
    { "coordinates",            kSystemInfo_coordinates,            OOJS_PROP_READONLY_CB },
    { "internalCoordinates",    kSystemInfo_internalCoordinates,    OOJS_PROP_READONLY_CB },
    { "galaxyID",               kSystemInfo_galaxyID,               OOJS_PROP_READONLY_CB },
    { "systemID",               kSystemInfo_systemID,               OOJS_PROP_READONLY_CB },
    { 0 }
};
 
 
static JSFunctionSpec sSystemInfoMethods[] =
{
    // JS name                  Function                    min args
    { "toString",               OOJSObjectWrapperToString,      0 },
    { "distanceToSystem",       SystemInfoDistanceToSystem,     1 },
    { "routeToSystem",          SystemInfoRouteToSystem,        1 },
    { "samplePrice",            SystemInfoSamplePrice,          1 },
    { "setProperty",            SystemInfoSetPropertyMethod,    3 },
    { 0 }
};
 
 
static JSFunctionSpec sSystemInfoStaticMethods[] =
{
    // JS name                  Function                    min args
    { "filteredSystems",        SystemInfoStaticFilteredSystems, 2 },
    { "setInterstellarProperty",SystemInfoStaticSetInterstellarProperty,    4 },
    { 0 }
};
 
 
// Helper class wrapped by JS SystemInfo objects
@interface OOSystemInfo: NSObject
{
@private
    OOGalaxyID              _galaxy;
    OOSystemID              _system;
    NSString                *_planetKey;
}
 
- (id) initWithGalaxy:(OOGalaxyID)galaxy system:(OOSystemID)system;
 
- (id) valueForKey:(NSString *)key;
- (void) setValue:(id)value forKey:(NSString *)key;
 
- (NSArray *) allKeys;
 
- (OOGalaxyID) galaxy;
- (OOSystemID) system;
//- (Random_Seed) systemSeed;
 
@end
 
 
DEFINE_JS_OBJECT_GETTER(JSSystemInfoGetSystemInfo, &sSystemInfoClass, sSystemInfoPrototype, OOSystemInfo);
 
 
@implementation OOSystemInfo
 
- (id) init
{
    [self release];
    return nil;
}
 
 
- (id) initWithGalaxy:(OOGalaxyID)galaxy system:(OOSystemID)system
{
    if (galaxy > kOOMaximumGalaxyID || system > kOOMaximumSystemID || system < kOOMinimumSystemID)
    {
        [self release];
        return nil;
    }
    
    if ((self = [super init]))
    {
        _galaxy = galaxy;
        _system = system;
        _planetKey = [[NSString stringWithFormat:@"%u %i", galaxy, system] retain];
    }
    return self;
}
 
 
- (void) dealloc
{
    [_planetKey release];
    
    [super dealloc];
}
 
 
- (NSString *) descriptionComponents
{
    return [NSString stringWithFormat:@"galaxy %u, system %i", _galaxy, _system];
}
 
 
- (NSString *) shortDescriptionComponents
{
    return _planetKey;
}
 
 
- (NSString *) oo_jsClassName
{
    return @"SystemInfo";
}
 
 
- (BOOL) isEqual:(id)other
{
    return other == self ||
           ([other isKindOfClass:[OOSystemInfo class]] &&
            [other galaxy] == _galaxy &&
            [other system] == _system);
                     
}
 
 
- (NSUInteger) hash
{
    NSUInteger hash = _galaxy;
    hash <<= 16;
    hash |= (uint16_t)_system;
    return hash;
}
 
 
- (id) valueForKey:(NSString *)key
{
    if ([UNIVERSE inInterstellarSpace] && _system == -1) 
    {
        return [[UNIVERSE currentSystemData] objectForKey:key];
    }
    return [UNIVERSE systemDataForGalaxy:_galaxy planet:_system key:key];
}
 
 
- (void) setValue:(id)value forKey:(NSString *)key
{
    NSString *manifest = [[OOJSScript currentlyRunningScript] propertyNamed:kLocalManifestProperty];
 
    [UNIVERSE setSystemDataForGalaxy:_galaxy planet:_system key:key value:value  fromManifest:manifest forLayer:OO_LAYER_OXP_DYNAMIC];
}
 
 
- (NSArray *) allKeys
{
    if ([UNIVERSE inInterstellarSpace] && _system == -1) 
    {
        return [[UNIVERSE currentSystemData] allKeys];
    }
    return [UNIVERSE systemDataKeysForGalaxy:_galaxy planet:_system];
}
 
 
- (OOGalaxyID) galaxy
{
    return _galaxy;
}
 
 
- (OOSystemID) system
{
    return _system;
}
 
 
/*- (Random_Seed) systemSeed
{
    NSAssert([PLAYER currentGalaxyID] == _galaxy, @"Attempt to use -[OOSystemInfo systemSeed] from a different galaxy.");
    return [UNIVERSE systemSeedForSystemNumber:_system];
    }*/
 
 
- (NSPoint) coordinates
{
    if ([UNIVERSE inInterstellarSpace] && _system == -1) 
    {
        return [PLAYER galaxy_coordinates];
    }
    return [UNIVERSE coordinatesForSystem:_system];
}
 
 
- (jsval) oo_jsValueInContext:(JSContext *)context
{
    JSObject                    *jsSelf = NULL;
    jsval                       result = JSVAL_NULL;
    
    jsSelf = JS_NewObject(context, &sSystemInfoClass, sSystemInfoPrototype, NULL);
    if (jsSelf != NULL)
    {
        if (!JS_SetPrivate(context, jsSelf, [self retain]))  jsSelf = NULL;
    }
    if (jsSelf != NULL)  result = OBJECT_TO_JSVAL(jsSelf);
    
    return result;
}
 
@end
 
 
 
void InitOOJSSystemInfo(JSContext *context, JSObject *global)
{
    sSystemInfoPrototype = JS_InitClass(context, global, NULL, &sSystemInfoClass, OOJSUnconstructableConstruct, 0, sSystemInfoProperties, sSystemInfoMethods, NULL, sSystemInfoStaticMethods);
    OOJSRegisterObjectConverter(&sSystemInfoClass, OOJSBasicPrivateObjectConverter);
}
 
 
jsval GetJSSystemInfoForSystem(JSContext *context, OOGalaxyID galaxy, OOSystemID system)
{
    OOJS_PROFILE_ENTER
    
    // Use cached object if possible.
    if (sCachedSystemInfo != NULL &&
        sCachedGalaxy == galaxy &&
        sCachedSystem == system)
    {
        return OBJECT_TO_JSVAL(sCachedSystemInfo);
    }
    
    // If not, create a new one.
    OOSystemInfo *info = nil;
    jsval result;
    OOJS_BEGIN_FULL_NATIVE(context)
    info = [[[OOSystemInfo alloc] initWithGalaxy:galaxy system:system] autorelease];
    OOJS_END_FULL_NATIVE
    
    if (EXPECT_NOT(info == nil))
    {
        OOJSReportWarning(context, @"Could not create system info object for galaxy %u, system %i.", galaxy, system);
    }
    
    result = OOJSValueFromNativeObject(context, info);
    
    // Cache is not a root; we clear it in finalize if necessary.
    sCachedSystemInfo = JSVAL_TO_OBJECT(result);
    sCachedGalaxy = galaxy;
    sCachedSystem = system;
    
    return result;
    
    OOJS_PROFILE_EXIT_JSVAL
}
 
 
static void SystemInfoFinalize(JSContext *context, JSObject *this)
{
    OOJS_PROFILE_ENTER
    
    [(id)JS_GetPrivate(context, this) release];
    JS_SetPrivate(context, this, nil);
    
    // Clear now-stale cache entry if appropriate.
    if (sCachedSystemInfo == this)  sCachedSystemInfo = NULL;
    
    OOJS_PROFILE_EXIT_VOID
}
 
 
static JSBool SystemInfoEnumerate(JSContext *context, JSObject *this, JSIterateOp enumOp, jsval *state, jsid *idp)
{
    OOJS_NATIVE_ENTER(context)
    
    NSEnumerator *enumerator = nil;
    
    switch (enumOp)
    {
        case JSENUMERATE_INIT:
        case JSENUMERATE_INIT_ALL:  // For ES5 Object.getOwnPropertyNames(). Since we have no non-enumerable properties, this is the same as _INIT.
        {
            OOSystemInfo *info = JS_GetPrivate(context, this);
            NSArray *keys = [info allKeys];
            enumerator = [[keys objectEnumerator] retain];
            *state = PRIVATE_TO_JSVAL(enumerator);
            
            NSUInteger count = [keys count];
            assert(count <= INT32_MAX);
            if (idp != NULL)  *idp = INT_TO_JSID((int32_t)count);
            return YES;
        }
        
        case JSENUMERATE_NEXT:
        {
            enumerator = JSVAL_TO_PRIVATE(*state);
            NSString *next = [enumerator nextObject];
            if (next != nil)
            {
                jsval val = [next oo_jsValueInContext:context];
                return JS_ValueToId(context, val, idp);
            }
            // else:
            *state = JSVAL_NULL;
            // Fall through.
        }
        
        case JSENUMERATE_DESTROY:
        {
            if (enumerator == nil && JSVAL_IS_DOUBLE(*state))
            {
                enumerator = JSVAL_TO_PRIVATE(*state);
            }
            [enumerator release];
            
            if (idp != NULL)  *idp = JSID_VOID;
            return YES;
        }
    }
    
    
    
    OOJS_NATIVE_EXIT
}
 
 
static JSBool SystemInfoDeleteProperty(JSContext *context, JSObject *this, jsid propID, jsval *value)
{
    OOJS_PROFILE_ENTER  // Any exception will be converted in SystemInfoSetProperty()
    
    jsval v = JSVAL_VOID;
    return SystemInfoSetProperty(context, this, propID, NO, &v);
    
    OOJS_PROFILE_EXIT
}
 
 
static JSBool SystemInfoGetProperty(JSContext *context, JSObject *this, jsid propID, jsval *value)
{
    OOJS_NATIVE_ENTER(context)
    
    if (this == sSystemInfoPrototype)
    {
        // Let SpiderMonkey handle access to the prototype object (where info will be nil).
        return YES;
    }
    
    OOSystemInfo    *info = OOJSNativeObjectOfClassFromJSObject(context, this, [OOSystemInfo class]);
    // What if we're trying to access a saved witchspace systemInfo object?
    BOOL savedInterstellarInfo = ![UNIVERSE inInterstellarSpace] && [info system] == -1;
    BOOL sameGalaxy = [PLAYER currentGalaxyID] == [info galaxy];
    
    
    if (JSID_IS_INT(propID))
    {
        switch (JSID_TO_INT(propID))
        {
            case kSystemInfo_coordinates:
                if (sameGalaxy && !savedInterstellarInfo)
                {
                    return VectorToJSValue(context, OOGalacticCoordinatesFromInternal([info coordinates]), value);
                }
                else
                {
                    OOJSReportError(context, @"Cannot read systemInfo values for %@.", savedInterstellarInfo ? @"invalid interstellar space reference" : @"other galaxies");
                    return NO;
                }
                break;
                
            case kSystemInfo_internalCoordinates:
                if (sameGalaxy && !savedInterstellarInfo)
                {
                    return NSPointToVectorJSValue(context, [info coordinates], value);
                }
                else
                {
                    OOJSReportError(context, @"Cannot read systemInfo values for %@.", savedInterstellarInfo ? @"invalid interstellar space reference" : @"other galaxies");
                    return NO;
                }
                break;
                
            case kSystemInfo_galaxyID:
                *value = INT_TO_JSVAL([info galaxy]);
                return YES;
                
            case kSystemInfo_systemID:
                *value = INT_TO_JSVAL([info system]);
                return YES;
                
            default:
                OOJSReportBadPropertySelector(context, this, propID, sSystemInfoProperties);
                return NO;
        }
    }
    else if (JSID_IS_STRING(propID))
    {
        NSString *key = OOStringFromJSString(context, JSID_TO_STRING(propID));
        
        OOSystemDescriptionManager *systemManager = [UNIVERSE systemManager];
        id propValue = nil;
        // interstellar space needs more work at this stage
        if ([info system] != -1)
        {
            propValue = [systemManager getProperty:key forSystem:[info system] inGalaxy:[info galaxy]];
        } else {
            propValue = [info valueForKey:key];
        }
        
        if (propValue != nil)
        {
            if ([propValue isKindOfClass:[NSNumber class]] || OOIsNumberLiteral([propValue description], YES))
            {
                BOOL OK = JS_NewNumberValue(context, [propValue doubleValue], value);
                if (!OK)
                {
                    *value = JSVAL_VOID;
                    return NO;
                }
            }
            else
            {
                *value = [propValue oo_jsValueInContext:context];
            }
        }
    }
    return YES;
    
    OOJS_NATIVE_EXIT
}
 
 
static JSBool SystemInfoSetProperty(JSContext *context, JSObject *this, jsid propID, JSBool strict, jsval *value)
{
    if (EXPECT_NOT(this == sSystemInfoPrototype))
    {
        // Let SpiderMonkey handle access to the prototype object (where info will be nil).
        return YES;
    }
    
    OOJS_NATIVE_ENTER(context);
    
    if (JSID_IS_STRING(propID))
    {
        NSString        *key = OOStringFromJSString(context, JSID_TO_STRING(propID));
        OOSystemInfo    *info = OOJSNativeObjectOfClassFromJSObject(context, this, [OOSystemInfo class]);
        
        [info setValue:OOStringFromJSValue(context, *value) forKey:key];
    }
    return YES;
    
    OOJS_NATIVE_EXIT
}
 
 
// distanceToSystem(sys : SystemInfo) : Number
static JSBool SystemInfoDistanceToSystem(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    OOSystemInfo            *thisInfo = nil;
    JSObject                *otherObj = NULL;
    OOSystemInfo            *otherInfo = nil;
    
    if (!JSSystemInfoGetSystemInfo(context, OOJS_THIS, &thisInfo))  return NO;
    if (argc < 1 || !JS_ValueToObject(context, OOJS_ARGV[0], &otherObj) || !JSSystemInfoGetSystemInfo(context, otherObj, &otherInfo))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"distanceToSystem", MIN(argc, 1U), OOJS_ARGV, nil, @"system info");
        return NO;
    }
    
    BOOL sameGalaxy = ([thisInfo galaxy] == [otherInfo galaxy]);
    if (!sameGalaxy)
    {
        OOJSReportErrorForCaller(context, @"SystemInfo", @"distanceToSystem", @"Cannot calculate distance for systems in other galaxies.");
        return NO;
    }
    
    NSPoint thisCoord = [thisInfo coordinates];
    NSPoint otherCoord = [otherInfo coordinates];
    
    OOJS_RETURN_DOUBLE(distanceBetweenPlanetPositions(thisCoord.x, thisCoord.y, otherCoord.x, otherCoord.y));
    
    OOJS_NATIVE_EXIT
}
 
 
// routeToSystem(sys : SystemInfo [, optimizedBy : String]) : Object
static JSBool SystemInfoRouteToSystem(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    OOSystemInfo            *thisInfo = nil;
    JSObject                *otherObj = NULL;
    OOSystemInfo            *otherInfo = nil;
    NSDictionary            *result = nil;
    OORouteType             routeType = OPTIMIZED_BY_JUMPS;
    
    if (!JSSystemInfoGetSystemInfo(context, OOJS_THIS, &thisInfo))  return NO;
    if (argc < 1 || !JS_ValueToObject(context, OOJS_ARGV[0], &otherObj) || !JSSystemInfoGetSystemInfo(context, otherObj, &otherInfo))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"routeToSystem", MIN(argc, 1U), OOJS_ARGV, nil, @"system info");
        return NO;
    }
    
    BOOL sameGalaxy = ([thisInfo galaxy] == [otherInfo galaxy]);
    if (!sameGalaxy)
    {
        OOJSReportErrorForCaller(context, @"SystemInfo", @"routeToSystem", @"Cannot calculate route for destinations in other galaxies.");
        return NO;
    }
    
    if (argc >= 2)
    {
        routeType = StringToRouteType(OOStringFromJSValue(context, OOJS_ARGV[1]));
    }
    
    OOJS_BEGIN_FULL_NATIVE(context)
    result = [UNIVERSE routeFromSystem:[thisInfo system] toSystem:[otherInfo system] optimizedBy:routeType];
    OOJS_END_FULL_NATIVE
    
    OOJS_RETURN_OBJECT(result);
    
    OOJS_NATIVE_EXIT
}
 
 
// samplePrice(commodity)
static JSBool SystemInfoSamplePrice(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    OOSystemInfo            *thisInfo = nil;
    
    if (!JSSystemInfoGetSystemInfo(context, OOJS_THIS, &thisInfo))  return NO;
    OOCommodityType commodity = OOStringFromJSValue(context, OOJS_ARGV[0]);
    if (EXPECT_NOT(![[UNIVERSE commodities] goodDefined:commodity]))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"samplePrice", MIN(argc, 1U), OOJS_ARGV, NULL, @"Unrecognised commodity type");
        return NO;
    }
 
    BOOL sameGalaxy = ([thisInfo galaxy] == [PLAYER galaxyNumber]);
    if (!sameGalaxy)
    {
        OOJSReportErrorForCaller(context, @"SystemInfo", @"samplePrice", @"Cannot calculate sample price for destinations in other galaxies.");
        return NO;
    }
 
    OOCreditsQuantity price = [[UNIVERSE commodities] samplePriceForCommodity:commodity inEconomy:[[thisInfo valueForKey:@"economy"] intValue] withScript:[thisInfo valueForKey:@"commodity_script"] inSystem:[thisInfo system]];
 
    return JS_NewNumberValue(context, price, &OOJS_RVAL);
    
    OOJS_NATIVE_EXIT
}
 
 
static JSBool SystemInfoSetPropertyMethod(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    OOSystemInfo            *thisInfo = nil;
    
    if (!JSSystemInfoGetSystemInfo(context, OOJS_THIS, &thisInfo))  return NO;
 
    NSString *property = nil;
    id value = nil;
    NSString *manifest = nil;
 
    int32 iValue;
 
    if (argc < 3)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(layer, property, value [,manifest])");
        return NO;
    }
    if (!JS_ValueToInt32(context, OOJS_ARGV[0], &iValue))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(layer, property, value [,manifest])");
        return NO;
    }
    if (iValue < 0 || iValue >= OO_SYSTEM_LAYERS)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"layer must be 0, 1, 2 or 3");
        return NO;
    }
    OOSystemLayer layer = (OOSystemLayer)iValue;
 
    property = OOStringFromJSValue(context, OOJS_ARGV[1]);
    if (!JSVAL_IS_NULL(OOJS_ARGV[2]))
    {
        value = OOJSNativeObjectFromJSValue(context, OOJS_ARGV[2]);
    }
    if (argc >= 4)
    {
        manifest = OOStringFromJSValue(context, OOJS_ARGV[3]);
    }
    else
    {
        manifest = [[OOJSScript currentlyRunningScript] propertyNamed:kLocalManifestProperty];
    }
 
    [UNIVERSE setSystemDataForGalaxy:[thisInfo galaxy] planet:[thisInfo system] key:property value:value fromManifest:manifest forLayer:layer];
 
    OOJS_RETURN_VOID;
    
    OOJS_NATIVE_EXIT
}
 
 
// filteredSystems(this : Object, predicate : Function) : Array
static JSBool SystemInfoStaticFilteredSystems(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    JSObject            *jsThis = NULL;
    
    // Get this and predicate arguments
    if (argc < 2 || !OOJSValueIsFunction(context, OOJS_ARGV[1]) || !JS_ValueToObject(context, OOJS_ARGV[0], &jsThis))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"filteredSystems", argc, OOJS_ARGV, nil, @"this and predicate function");
        return NO;
    }
    jsval predicate = OOJS_ARGV[1];
    
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
    NSMutableArray *result = [NSMutableArray arrayWithCapacity:256];
    
    // Not OOJS_BEGIN_FULL_NATIVE() - we use JSAPI while paused.
    OOJSPauseTimeLimiter();
    
    // Iterate over systems.
    BOOL OK = result != nil;
    OOGalaxyID galaxy = [PLAYER currentGalaxyID];
    OOSystemID system;
    for (system = 0; system <= kOOMaximumSystemID; system++)
    {
        // NOTE: this deliberately bypasses the cache, since iteration is inherently unfriendly to a single-item cache.
        OOSystemInfo *info = [[[OOSystemInfo alloc] initWithGalaxy:galaxy system:system] autorelease];
        jsval args[1] = { OOJSValueFromNativeObject(context, info) };
        
        jsval rval = JSVAL_VOID;
        OOJSResumeTimeLimiter();
        OK = JS_CallFunctionValue(context, jsThis, predicate, 1, args, &rval);
        OOJSPauseTimeLimiter();
        
        if (OK)
        {
            if (JS_IsExceptionPending(context))
            {
                JS_ReportPendingException(context);
                OK = NO;
            }
        }
        
        if (OK)
        {
            JSBool boolVal;
            if (JS_ValueToBoolean(context, rval, &boolVal) && boolVal)
            {
                [result addObject:info];
            }
        }
        
        if (!OK)  break;
    }
    
    if (OK)
    {
        OOJS_SET_RVAL([result oo_jsValueInContext:context]);
    }
    else
    {
        OOJS_SET_RVAL(JSVAL_VOID);
    }
 
    [pool release];
    
    OOJSResumeTimeLimiter();
    return OK;
    
    OOJS_NATIVE_EXIT
}
 
 
static JSBool SystemInfoStaticSetInterstellarProperty(JSContext *context, uintN argc, jsval *vp)
{
    OOJS_NATIVE_ENTER(context)
    
    NSString *property = nil;
    id value = nil;
    NSString *manifest = nil;
 
    int32 iValue;
    OOGalaxyID g;
    OOSystemID s1,s2;
 
    if (argc < 6)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(galaxy, fromsystem, tosystem, layer, property, value [,manifest])");
        return NO;
    }
    if (!JS_ValueToInt32(context, OOJS_ARGV[0], &iValue))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(galaxy, fromsystem, tosystem, layer, property, value [,manifest])");
        return NO;
    }
    if (iValue < 0 || iValue > kOOMaximumGalaxyID)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"galaxy out of range");
        return NO;
    }
    else
    {
        g = (OOGalaxyID)iValue;
    }
 
    if (!JS_ValueToInt32(context, OOJS_ARGV[1], &iValue))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(galaxy, fromsystem, tosystem, layer, property, value [,manifest])");
        return NO;
    }
    if (iValue < 0 || iValue > kOOMaximumSystemID)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"fromsystem out of range");
        return NO;
    }
    else
    {
        s1 = (OOSystemID)iValue;
    }
 
    if (!JS_ValueToInt32(context, OOJS_ARGV[2], &iValue))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(galaxy, fromsystem, tosystem, layer, property, value [,manifest])");
        return NO;
    }
    if (iValue < 0 || iValue > kOOMaximumSystemID)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"tosystem out of range");
        return NO;
    }
    else
    {
        s2 = (OOSystemID)iValue;
    }
 
    if (!JS_ValueToInt32(context, OOJS_ARGV[3], &iValue))
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"setProperty(galaxy, fromsystem, tosystem, layer, property, value [,manifest])");
        return NO;
    }
    if (iValue < 0 || iValue >= OO_SYSTEM_LAYERS)
    {
        OOJSReportBadArguments(context, @"SystemInfo", @"setInterstellarProperty", MIN(argc, 3U), OOJS_ARGV, NULL, @"layer must be 0, 1, 2 or 3");
        return NO;
    }
    OOSystemLayer layer = (OOSystemLayer)iValue;
 
    property = OOStringFromJSValue(context, OOJS_ARGV[4]);
    if (!JSVAL_IS_NULL(OOJS_ARGV[5]))
    {
        value = OOJSNativeObjectFromJSValue(context, OOJS_ARGV[5]);
    }
    if (argc >= 7)
    {
        manifest = OOStringFromJSValue(context, OOJS_ARGV[6]);
    }
    else
    {
        manifest = [[OOJSScript currentlyRunningScript] propertyNamed:kLocalManifestProperty];
    }
 
    NSString *key = [NSString stringWithFormat:@"interstellar: %u %u %u",g,s1,s2];
    
    [[UNIVERSE systemManager] setProperty:property forSystemKey:key andLayer:layer toValue:value fromManifest:manifest];
 
    OOJS_RETURN_VOID;
    
    OOJS_NATIVE_EXIT
}