GLLModel.m

//
//  GLLModel.m
//  GLLara
//
//  Created by Torsten Kammer on 31.08.12.
//  Copyright (c) 2012 Torsten Kammer. All rights reserved.
//

#import "GLLModel.h"

#import "NSArray+Map.h"
#import "GLLASCIIScanner.h"
#import "GLLModelBone.h"
#import "GLLModelMesh.h"
#import "GLLModelMeshV3.h"
#import "GLLModelObj.h"
#import "TRInDataStream.h"
#import "TROutDataStream.h"

#import "GLLara-Swift.h"

NSString *GLLModelLoadingErrorDomain = @"GLL Model loading error domain";

@interface GLLModel ()

// Adds a single mesh to the object, splitting it up into multiple parts if necessary (as specified by the model parameters). Also takes care to add it to the mesh groups and so on.
- (void)_addMesh:(GLLModelMesh *)mesh toArray:(NSMutableArray *)array;

@end

static NSCache *cachedModels;

@implementation GLLModel

+ (void)initialize
{
    cachedModels = [[NSCache alloc] init];
}

+ (id)cachedModelFromFile:(NSURL *)file parent:(GLLModel *)parent error:(NSError *__autoreleasing*)error;
{
    id key = file.absoluteString;
    if (parent != nil)
        key = [file.absoluteString stringByAppendingFormat:@"\n%@", parent.baseURL.absoluteString];
    
    id result = [cachedModels objectForKey:key];
    if (!result)
    {
        if ([file.path hasSuffix:@".mesh"])
        {
            result = [[self alloc] initBinaryFromFile:file parent:parent error:error];
            if (!result) return nil;
        }
        else if ([file.path hasSuffix:@".xps"])
        {
            result = [[self alloc] initBinaryFromFile:file parent:parent error:error];
            if (!result) return nil;
        }
        else if ([file.path hasSuffix:@".mesh.ascii"])
        {
            result = [[self alloc] initASCIIFromFile:file parent:parent error:error];
            if (!result) return nil;
        }
        else if ([file.path hasSuffix:@".obj"])
        {
            result = [[GLLModelObj alloc] initWithContentsOfURL:file error:error];
            if (!result) return nil;
        }
        else if ([file.path hasSuffix:@".gltf"])
        {
            result = [[GLLModelGltf alloc] initWithUrl:file isBinary:NO error:error];
            if (!result) return nil;
        }
        else if ([file.path hasSuffix:@".glb"])
        {
            result = [[GLLModelGltf alloc] initWithUrl:file isBinary:YES error:error];
            if (!result) return nil;
        }
        else
        {
            if (error)
            {
                // Find display name for this extension
                CFStringRef fileType = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (__bridge CFStringRef) file.pathExtension, NULL);
                CFStringRef fileTypeDescription = UTTypeCopyDescription(fileType);
                CFRelease(fileType);
                
                *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_FileTypeNotSupported userInfo:@{
                                                                                                                                       NSLocalizedDescriptionKey : [NSString stringWithFormat:NSLocalizedString(@"Files of type %@ are not supported.", @"Tried to load unsupported format"), (__bridge NSString *)fileTypeDescription],
                                                                                                                                       NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"Only .mesh, .mesh.ascii and .obj files can be loaded.", @"Tried to load unsupported format")}];
                CFRelease(fileTypeDescription);
            }
            return nil;
        }
        
        [cachedModels setObject:result forKey:key];
    }
    return result;
}

- (id)initBinaryFromFile:(NSURL *)file parent:(GLLModel *)parent error:(NSError *__autoreleasing*)error;
{
    NSData *data = [NSData dataWithContentsOfURL:file options:NSDataReadingMappedIfSafe error:error];
    if (!data) return nil;
    
    return [self initBinaryFromData:data baseURL:file parent:parent error:error];
}

- (id)initBinaryFromData:(NSData *)data baseURL:(NSURL *)baseURL parent:(GLLModel *)parent error:(NSError *__autoreleasing*)error;
{
    if (!(self = [super init])) return nil;
    
    if (data.length < sizeof(uint32_t [2])) // Minimum length
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file is shorter than the minimum file size.", @"Premature end of file error"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"A model has to be at least eight bytes long. This file may be corrupted.", @"Premature end of file error.")}];
        return nil;
    }
    
    _baseURL = baseURL;
    _parameters = [GLLModelParams parametersForModel:self error:error];
    if (!_parameters)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_ParametersNotFound userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"Parameters for file could not be found.", @"Loading error: No parameters for this model."),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"This file is neither a generic item nor a known named file.", @"Loading error: No parameters for this model.")}];
        return nil;
    }
    
    TRInDataStream *stream = [[TRInDataStream alloc] initWithData:data];
    
    NSUInteger genericItemVersion = 0;
    
    NSUInteger header = [stream readUint32];
    if (header == 323232)
    {
        /*
         * This is my idea of how to support the Generic Item 2 format. Note
         * that this is all reverse engineered from looking at files. I do not
         * know whether my variable names are correct, and I do not interpret
         * it in any way.
         */
        NSLog(@"Warning: Using experimental, hackish, ugly Generic Item 2 support");
        genericItemVersion = 2;
        
        // First: Two uint16s. My guess: Major, then minor version.
        // Always 1 and 12.
        uint16_t possiblyMajorVersion = [stream readUint16];
        uint16_t possiblyMinorVersion = [stream readUint16];
        if (possiblyMajorVersion == 0x0001)
        {
            if (possiblyMinorVersion != 0x000C)
            {
                if (error)
                    *error = [NSError errorWithDomain:@"GLLModel" code:10 userInfo:@{
                                                                                     NSLocalizedDescriptionKey : NSLocalizedString(@"New-style Generic Item has unknown minor version for major version 1.", @"Generic Item 2: Second uint32 unexpected"),
                                                                                     NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"If there is a .mesh.ascii version, try opening that.", @"New-style binary generic item won't work.")}];
                return nil;
            }
        }
        else if (possiblyMajorVersion == 0x0002)
        {
            genericItemVersion = 3;
            if (possiblyMinorVersion != 0x0000F && possiblyMinorVersion != 0x000E)
            {
                if (error)
                    *error = [NSError errorWithDomain:@"GLLModel" code:10 userInfo:@{
                                                                                     NSLocalizedDescriptionKey : NSLocalizedString(@"New-style Generic Item has unknown minor version for major version 2.", @"Generic Item 2: Second uint32 unexpected"),
                                                                                     NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"If there is a .mesh.ascii version, try opening that.", @"New-style binary generic item won't work.")}];
                return nil;
            }
        }
        else if (possiblyMajorVersion == 0x0003)
        {
            genericItemVersion = 4;
        }
        else
        {
            if (error)
                *error = [NSError errorWithDomain:@"GLLModel" code:10 userInfo:@{
                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"New-style Generic Item has unknown major version.", @"Generic Item 2: Second uint32 unexpected"),
                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"If there is a .mesh.ascii version, try opening that.", @"New-style binary generic item won't work.")}];
            return nil;
        }
        
        // A string. In all files that I've seen it is XNAaraL.
        NSString *toolAuthor = [stream readPascalString];
        if (![toolAuthor isEqual:@"XNAaraL"])
            NSLog(@"Unusual string at offset %lu: Expected XNAaraL, got %@", stream.position, toolAuthor);
        
        // A count of… thingies that appear after the next three strings. Skip that count times four bytes and you are ready to read bones.
        NSUInteger countOfUnknownint32s = [stream readUint32];
        
        // Three strings. The third is often just a letter (e.g. X).
        NSString *firstAuxilaryString = [stream readPascalString];
        NSString *secondAuxilaryString = [stream readPascalString];
        NSString *thirdAuxilaryString = [stream readPascalString];
        NSLog(@"Auxilary strings: %@, %@, %@", firstAuxilaryString, secondAuxilaryString, thirdAuxilaryString);
        
        // The thingies from above. All the same value in the models I've seen so far, typically small integers (0 or 3). Not sure what count relates to; is not bone count, mesh count, bone count + mesh count or anything like that.
        [stream skipBytes:4 * countOfUnknownint32s];
        
        // Read number of bones.
        header = [stream readUint32];
    }
    
    NSUInteger numBones = header;
    if (numBones*15 > (stream.levelData.length - stream.position)) // Sanity check: The shortest bone is 15 bytes
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file cannot contain as many bones as it claims.", @"numBones too large error (short description)"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : [NSString stringWithFormat:NSLocalizedString(@"The file declares that it contains %lu bones, but it is shorter than the minimum size required to store all of them. This can happen if a file in the ASCII format is read as Binary.", @"numBones too large error (long description)"), numBones]}];
        return nil;
    }
    
    NSMutableArray *bones = [[NSMutableArray alloc] initWithCapacity:numBones];
    for (NSUInteger i = 0; i < numBones; i++)
    {
        GLLModelBone *bone = [[GLLModelBone alloc] initFromSequentialData:stream partOfModel:self atIndex:i error:error];
        if (!bone) return nil;
        [bones addObject:bone];
    }
    _bones = [bones copy];
    for (GLLModelBone *bone in _bones)
        if (![bone findParentsAndChildrenError:error])
            return nil;
    
    if (!stream.isValid)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file is missing some data.", @"Premature end of file error"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"The file contains only bones and no meshes. Maybe it was damaged?", @"Premature end of file error")}];
        return nil;
    }
    
    NSUInteger numMeshes = [stream readUint32];
    NSMutableArray *meshes = [[NSMutableArray alloc] initWithCapacity:numMeshes];
    Class meshClass = [GLLModelMesh class];
    if (genericItemVersion >= 4) {
        meshClass = [GLLModelMeshV4 class];
    } else if (genericItemVersion >= 3) {
        meshClass = [GLLModelMeshV3 class];
    }
    for (NSUInteger i = 0; i < numMeshes; i++)
    {
        GLLModelMesh *mesh = [[meshClass alloc] initFromStream:stream partOfModel:self error:error];
        if (!mesh) return nil;
        [self _addMesh:mesh toArray:meshes];
    }
    _meshes = meshes;
    
    if (!stream.isValid)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file is missing some data.", @"Premature end of file error"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"The mesh data is incomplete. The file may be damaged.", @"Premature end of file error")
                                                                                                                                 }];
        return nil;
    }
    
    if ((genericItemVersion >= 2) && !stream.isAtEnd)
    {
        // A string; always $$XNAaraL$$
        NSString *footerAuthor = [stream readPascalString];
        if (![footerAuthor isEqual:@"$$XNAaraL$$"])
            NSLog(@"Unusual string at offset %lu: Expected $$XNAaraL$$, got %@", stream.position, footerAuthor);
        
        NSString *copyrightNotice = [stream readPascalString];
        NSLog(@"Copyright notice: %@", copyrightNotice);
        
        NSString *creationToolText = [stream readPascalString];
        NSLog(@"Creation tool text: %@", creationToolText);
        
        if (!stream.isValid)
        {
            if (error)
                *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                     NSLocalizedDescriptionKey : NSLocalizedString(@"The file is missing some data.", @"Premature end of file error"),
                                                                                                                                     NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"The Generic Item 2 footer section is incomplete. The file may be damaged.", @"Premature end of file error") }];
        }
    }
    
    return self;
}

- (id)initASCIIFromFile:(NSURL *)file parent:(GLLModel *)parent error:(NSError *__autoreleasing*)error;
{
    NSString *source = [NSString stringWithContentsOfURL:file usedEncoding:NULL error:error];
    if (!source) return nil;
    
    return [self initASCIIFromString:source baseURL:file parent:parent error:error];
}

- (id)initASCIIFromString:(NSString *)source baseURL:(NSURL *)baseURL parent:(GLLModel *)parent error:(NSError *__autoreleasing*)error;
{
    if (!(self = [super init])) return nil;
    
    _baseURL = baseURL;
    _parameters = [GLLModelParams parametersForModel:self error:error];
    if (!_parameters)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_ParametersNotFound userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"Parameters for file could not be found.", @"Loading error: No parameters for this model."),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"This file is neither a generic item nor a known named file.", @"Loading error: No parameters for this model.")}];
        return nil;
    }
    
    GLLASCIIScanner *scanner = [[GLLASCIIScanner alloc] initWithString:source];
    
    NSUInteger numBones = [scanner readUint32];
    NSMutableArray *bones = [[NSMutableArray alloc] initWithCapacity:numBones];
    for (NSUInteger i = 0; i < numBones; i++)
    {
        GLLModelBone *bone = [[GLLModelBone alloc] initFromSequentialData:scanner partOfModel:self atIndex:i  error:error];
        if (!bone) return nil;
        
        // Check whether parent has this bone and defer to it instead
        GLLModelBone *boneFromParent = [parent boneForName:bone.name];
        if (boneFromParent)
            [bones addObject:boneFromParent];
        else
            [bones addObject:bone];
    }
    _bones = [bones copy];
    for (GLLModelBone *bone in _bones)
        if (![bone findParentsAndChildrenError:error])
            return nil;
    
    if (!scanner.isValid)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file is missing some data.", @"Premature end of file error"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"The file contains only bones and no meshes. Maybe it was damaged?", @"Premature end of file error") }];
        return nil;
    }
    
    NSUInteger numMeshes = [scanner readUint32];
    NSMutableArray *meshes = [[NSMutableArray alloc] initWithCapacity:numMeshes];
    for (NSUInteger i = 0; i < numMeshes; i++)
    {
        GLLModelMesh *mesh = [[GLLModelMesh alloc] initFromScanner:scanner partOfModel:self error:error];
        if (!mesh) return nil;
        [self _addMesh:mesh toArray:meshes];
    }
    _meshes = meshes;
    
    if (!scanner.isValid)
    {
        if (error)
            *error = [NSError errorWithDomain:GLLModelLoadingErrorDomain code:GLLModelLoadingError_PrematureEndOfFile userInfo:@{
                                                                                                                                 NSLocalizedDescriptionKey : NSLocalizedString(@"The file is missing some data.", @"Premature end of file error"),
                                                                                                                                 NSLocalizedRecoverySuggestionErrorKey : NSLocalizedString(@"The mesh data is incomplete. The file may be damaged.", @"Premature end of file error")
                                                                                                                                 }];
        return nil;
    }
    
    return self;
}

#pragma mark - Accessors

- (BOOL)hasBones
{
    return self.bones.count > 0;
}

- (NSArray<GLLModelBone *> *)rootBones
{
    return [self.bones filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"hasParent == NO"]];
}

- (NSArray<NSString *> *)cameraTargetNames
{
    return self.parameters.cameraTargets;
}
- (NSArray<NSString *> *)boneNamesForCameraTarget:(NSString *)target;
{
    return [self.parameters boneNamesForCameraTarget:target];
}

- (GLLModelBone *)boneForName:(NSString *)name;
{
    return [self.bones firstObjectMatching:^BOOL(GLLModelBone *bone){
        return [bone.name isEqual:name];
    }];
}

#pragma mark - Private methods

- (void)_addMesh:(GLLModelMesh *)mesh toArray:(NSMutableArray *)array;
{
    GLLMeshParams *params = [self.parameters paramsForMesh:mesh.name];
    if (params.splitters.count > 0)
    {
        [array addObjectsFromArray:[params.splitters map:^(GLLMeshSplitter *splitter) {
            return [mesh partialMeshFromSplitter:splitter];
        }]];
    }
    else
    {
        [array addObject:mesh];
    }
}

@end