swift CGPDFDocument parsing - swift

Question

I'm trying to use Swift to parse the contents of PDF documents, following Apple's programming guide (in which all the examples are ObjC...)
let filepath = "/Users/ben/Desktop/Test.pdf"
let localUrl = filepath as CFString
if let pdfURL = CFURLCreateWithFileSystemPath(nil, localUrl, CFURLPathStyle.cfurlposixPathStyle, false) {
if let pdf = CGPDFDocument(pdfURL) {
if let inf = pdf.info {
CGPDFDictionaryApplyFunction(inf, { (key, object, info) -> Void in
print("\(key), \(object), \(info)")
}, nil)
}
if let cat = pdf.catalog {
CGPDFDictionaryApplyFunction(cat, { (key, object, info) -> Void in
print("\(key), \(object), \(info)")
}, nil)
}
}
}
While this seems to produce some results, it's just strings of hex digits.
0x00007ff29f43ce00, 0x00007ff29f492bd0, nil
0x00007ff29f443b60, 0x00007ff29f492cd0, nil
0x00007ff29f482590, 0x00007ff29f492dd0, nil
0x00007ff29f482a40, 0x00007ff29f492ed0, nil
0x00007ff29f482e30, 0x00007ff29f492fe0, nil
0x00007ff29f47da20, 0x00007ff29f4930e0, nil
0x00007ff29f474ac0, 0x00007ff29f842b50, nil
0x00007ff29f43f5d0, 0x00007ff29f842bf0, nil
0x00007ff29f485eb0, 0x00007ff29f842a60, nil
0x00007ff29f482f70, 0x00007ff29f842ab0, nil
0x00007ff29f48b1c0, 0x00007ff29f48f6d0, nil
So how do I get the actual data? Ideally, I'm trying to get at the document metadata and things like fonts contained.

Answer 1

Swift 4 - Here is an updated version of Daniel's excellent example which compiles in Swift 4.
import Foundation
import Quartz
print("Hello, World!")
func printPDFKeys( key: UnsafePointer<Int8>, object: CGPDFObjectRef) { //, info: UnsafeMutableRawPointer) {
// let _: CGPDFDictionaryRef = CGPDFDictionaryRef(info)
let keyString = String(cString: UnsafePointer<CChar>(key), encoding: .isoLatin1)
let objectType = CGPDFObjectGetType(object)
if keyString == nil {
return
}
print("key \(keyString!) is present in dictionary, type \(objectType.rawValue)")
var ptrObjectValue:UnsafePointer<Int8>? = nil
switch objectType {
// ObjectType is enum of:
// Null
// Boolean
// Integer
// Real
// Name
// String
// Array
// Dictionary
// Stream
case .boolean:
// Boolean
var objectBoolean:CGPDFBoolean = 0
if CGPDFObjectGetValue(object, objectType, &objectBoolean) {
let testbool = NSNumber(value: objectBoolean)
print("Boolean value \(testbool)")
}
case .integer:
// Integer
var objectInteger:CGPDFInteger? = nil
if CGPDFObjectGetValue(object, objectType, &objectInteger) {
print("Integer value \(objectInteger)")
}
case .real:
// Real
var objectReal:CGPDFReal? = nil
if CGPDFObjectGetValue(object, objectType, &objectReal) {
print("Real value \(objectReal)")
}
case .name:
// Name
if (CGPDFObjectGetValue(object, objectType, &ptrObjectValue)) {
let stringName = String(cString: UnsafePointer<CChar>(ptrObjectValue!), encoding: String.Encoding.isoLatin1)
print("Name value: \(stringName!)")
}
case .string:
// String
_ = CGPDFObjectGetValue(object, objectType, &ptrObjectValue)
let stringValue = CGPDFStringCopyTextString(OpaquePointer(ptrObjectValue!))
print("String value: \(stringValue!)")
case .array:
// Array
print("Array")
var objectArray:CGPDFArrayRef? = nil
if (CGPDFObjectGetValue(object, objectType, &objectArray))
{
print("array: \(arrayFromPDFArray(pdfArray: objectArray!))")
}
case .dictionary:
// Dictionary
var objectDictionary:CGPDFDictionaryRef? = nil
if (CGPDFObjectGetValue(object, objectType, &objectDictionary)) {
let count = CGPDFDictionaryGetCount(objectDictionary!)
print("Found dictionary with \(count) entries")
if !(keyString == "Parent") && !(keyString == "P") {
//catalogLevel = catalogLevel + 1
CGPDFDictionaryApplyFunction(objectDictionary!, { (key, object, info) -> Void in
printPDFKeys(key: key, object: object) // , info: info)
}, nil)
// CGPDFDictionaryApplyFunction(objectDictionary!, printPDFKeys as! CGPDFDictionaryApplierFunction, nil)
//catalogLevel = catalogLevel - 1
}
}
case .stream:
// Stream
print("Stream")
var objectStream:CGPDFStreamRef? = nil
if (CGPDFObjectGetValue(object, objectType, &objectStream)) {
let _: CGPDFDictionaryRef = CGPDFStreamGetDictionary( objectStream! )!
var fmt: CGPDFDataFormat = .raw
let streamData: CFData = CGPDFStreamCopyData(objectStream!, &fmt)!;
let data = NSData(data: streamData as Data)
let dataString = NSString(data: data as Data, encoding: String.Encoding.utf8.rawValue)
let dataLength: Int = CFDataGetLength(streamData)
print("data stream (length=\(dataLength)):")
if dataLength < 400 {
print(dataString)
}
}
default:
print("Null")
}
}
// convert a PDF array into an objC one
func arrayFromPDFArray(pdfArray: CGPDFArrayRef ) -> NSMutableArray {
var _:Int = 0
let tmpArray: NSMutableArray = NSMutableArray()
let count = CGPDFArrayGetCount(pdfArray)
for i in 0..<count {
var value:CGPDFObjectRef? = nil
if (CGPDFArrayGetObject(pdfArray, i, &value)) {
if let object = objectForPDFObject(object: value!) {
tmpArray.add(object)
}
}
}
return tmpArray
}
func objectForPDFObject( object: CGPDFObjectRef) -> AnyObject? {
let objectType: CGPDFObjectType = CGPDFObjectGetType(object)
var ptrObjectValue:UnsafePointer<Int8>? = nil
switch (objectType) {
case .boolean:
// Boolean
var objectBoolean = CGPDFBoolean()
if CGPDFObjectGetValue(object, objectType, &objectBoolean) {
let testbool = NSNumber(value: objectBoolean)
return testbool
}
case .integer:
// Integer
var objectInteger = CGPDFInteger()
if CGPDFObjectGetValue(object, objectType, &objectInteger) {
return objectInteger as AnyObject
}
case .real:
// Real
var objectReal = CGPDFReal()
if CGPDFObjectGetValue(object, objectType, &objectReal) {
return objectReal as AnyObject
}
case .string:
_ = CGPDFObjectGetValue(object, objectType, &ptrObjectValue)
let stringValue = CGPDFStringCopyTextString(OpaquePointer(ptrObjectValue!))
return stringValue
case .dictionary:
// Dictionary
var objectDictionary:CGPDFDictionaryRef? = nil
if (CGPDFObjectGetValue(object, objectType, &objectDictionary)) {
let count = CGPDFDictionaryGetCount(objectDictionary!)
print("In array, found dictionary with \(count) entries")
CGPDFDictionaryApplyFunction(objectDictionary!, { (key, object, info) -> Void in
printPDFKeys(key: key, object: object) // , info: info)
}, nil)
// CGPDFDictionaryApplyFunction(objectDictionary!, printPDFKeys as! CGPDFDictionaryApplierFunction, nil)
}
case .stream:
// Stream
var objectStream:CGPDFStreamRef? = nil
if (CGPDFObjectGetValue(object, objectType, &objectStream)) {
let _: CGPDFDictionaryRef = CGPDFStreamGetDictionary( objectStream! )!
var fmt: CGPDFDataFormat = .raw
let streamData: CFData = CGPDFStreamCopyData(objectStream!, &fmt)!;
let data = NSData(data: streamData as Data)
let dataString = NSString(data: data as Data, encoding: String.Encoding.utf8.rawValue)
print("data stream (length=\(CFDataGetLength(streamData))):")
return dataString
}
default:
return nil
}
return nil
}
func parse () {
let filepath = ("~/Desktop/doc.pdf" as NSString).expandingTildeInPath
let urlDocument = NSURL(fileURLWithPath: filepath)
let myDocument = CGPDFDocument(urlDocument)
if myDocument != nil {
let numPages = myDocument?.numberOfPages
print("Number of pages: \(numPages)")
// Get complete catalog
let myCatalog = myDocument?.catalog
CGPDFDictionaryApplyFunction(myCatalog!, { (key, object, info) -> Void in
printPDFKeys(key: key, object: object) // , info: info)
}, nil)
// CGPDFDictionaryApplyFunction(myCatalog!, printPDFKeys, nil)
let myInfo = myDocument?.info
CGPDFDictionaryApplyFunction(myInfo!, { (key, object, info) -> Void in
printPDFKeys(key: key, object: object) // , info: info)
}, nil)
// CGPDFDictionaryApplyFunction(myInfo!, printPDFKeys, nil)
} else {
print("Cannot open PDF document")
}
}
parse()

Answer 2

Your parsing retrieving high level dictionary and info data is correct, but you need to expand the decoding in CGPDFDictionaryApplyFunction to display the values of PDF data according their types (integer, string, array, dictionary, and so on). The syntax of the CGPDFDictionaryApplierFunction you are calling is:
typealias CGPDFDictionaryApplierFunction = (UnsafePointer<Int8>, COpaquePointer, UnsafeMutablePointer<()>) -> Void
Your program is displaying the pointers to the data, you could access the data values according their types as below (Swift 2):
let filepath = "/Users/ben/Desktop/Test.pdf"
let urlDocument = NSURL(fileURLWithPath: filepath)
let myDocument = CGPDFDocumentCreateWithURL(urlDocument)
if myDocument != nil {
let numPages = CGPDFDocumentGetNumberOfPages(myDocument)
print("Number of pages: \(numPages)")
// Get complete catalog
let myCatalog = CGPDFDocumentGetCatalog(myDocument)
CGPDFDictionaryApplyFunction(myCatalog, printPDFKeys, nil)
let myInfo = CGPDFDocumentGetInfo(myDocument)
CGPDFDictionaryApplyFunction(myInfo, printPDFKeys, nil)
} else {
print("Cannot open PDF document")
}
In order to be called from the CGPDFDictionaryApplyFunction, the printPDFKeys is to be called as a global function (outside your main class), alternately you could insert the code in a closure of CGPDFDictionaryApplyFunction as in your example above. The below code is shortened and is not including complete protection against errors and null values.
func printPDFKeys( key: UnsafePointer<Int8>, object: COpaquePointer, info: UnsafeMutablePointer<()>) {
let contentDict: CGPDFDictionaryRef = CGPDFDictionaryRef(info)
let keyString = String(CString: UnsafePointer<CChar>(key), encoding: NSISOLatin1StringEncoding)
let objectType = CGPDFObjectGetType(object)
if keyString == nil {
return
}
print("key \(keyString!) is present in dictionary, type \(objectType.rawValue)")
var ptrObjectValue = UnsafePointer<Int8>()
switch objectType {
// ObjectType is enum of:
// Null
// Boolean
// Integer
// Real
// Name
// String
// Array
// Dictionary
// Stream
case .Boolean:
// Boolean
var objectBoolean = CGPDFBoolean()
if CGPDFObjectGetValue(object, objectType, &objectBoolean) {
let testbool = NSNumber(unsignedChar: objectBoolean)
print("Boolean value \(testbool)")
}
case .Integer:
// Integer
var objectInteger = CGPDFInteger()
if CGPDFObjectGetValue(object, objectType, &objectInteger) {
print("Integer value \(objectInteger)")
}
case .Real:
// Real
var objectReal = CGPDFReal()
if CGPDFObjectGetValue(object, objectType, &objectReal) {
print("Real value \(objectReal)")
}
case .Name:
// Name
if (CGPDFObjectGetValue(object, objectType, &ptrObjectValue)) {
let stringName = String(CString: UnsafePointer<CChar>(ptrObjectValue), encoding: NSISOLatin1StringEncoding)
print("Name value: \(stringName!)")
}
case .String:
// String
let valueFound = CGPDFObjectGetValue(object, objectType, &ptrObjectValue)
let stringValue = CGPDFStringCopyTextString(COpaquePointer(ptrObjectValue))
print("String value: \(stringValue!)")
case .Array:
// Array
print("Array")
var objectArray = CGPDFArrayRef()
if (CGPDFObjectGetValue(object, objectType, &objectArray))
{
print("array: \(arrayFromPDFArray(objectArray))")
}
case .Dictionary:
// Dictionary
var objectDictionary = CGPDFDictionaryRef()
if (CGPDFObjectGetValue(object, objectType, &objectDictionary)) {
let count = CGPDFDictionaryGetCount(objectDictionary)
print("Found dictionary with \(count) entries")
if !(keyString == "Parent") && !(keyString == "P") {
//catalogLevel = catalogLevel + 1
CGPDFDictionaryApplyFunction(objectDictionary, printPDFKeys, nil)
//catalogLevel = catalogLevel - 1
}
}
case .Stream:
// Stream
print("Stream")
var objectStream = CGPDFStreamRef()
if (CGPDFObjectGetValue(object, objectType, &objectStream)) {
let dict: CGPDFDictionaryRef = CGPDFStreamGetDictionary( objectStream )
var fmt: CGPDFDataFormat = .Raw
let streamData: CFDataRef = CGPDFStreamCopyData(objectStream, &fmt)!;
let data = NSData(data: streamData)
let dataString = NSString(data: data, encoding: NSUTF8StringEncoding)
let dataLength: Int = CFDataGetLength(streamData)
print("data stream (length=\(dataLength)):")
if dataLength < 400 {
print(dataString)
}
}
default:
print("Null")
}
}
// convert a PDF array into an objC one
func arrayFromPDFArray(pdfArray: CGPDFArrayRef ) -> NSMutableArray {
var i:Int = 0
var tmpArray: NSMutableArray = NSMutableArray()
let count = CGPDFArrayGetCount(pdfArray)
for i in 0..<count {
var value = CGPDFObjectRef()
if (CGPDFArrayGetObject(pdfArray, i, &value)) {
if let object = objectForPDFObject(value) {
tmpArray.addObject(object)
}
}
}
return tmpArray
}
func objectForPDFObject( object: CGPDFObjectRef) -> AnyObject? {
let objectType: CGPDFObjectType = CGPDFObjectGetType(object)
var ptrObjectValue = UnsafePointer<Int8>()
switch (objectType) {
case .Boolean:
// Boolean
var objectBoolean = CGPDFBoolean()
if CGPDFObjectGetValue(object, objectType, &objectBoolean) {
let testbool = NSNumber(unsignedChar: objectBoolean)
return testbool
}
case .Integer:
// Integer
var objectInteger = CGPDFInteger()
if CGPDFObjectGetValue(object, objectType, &objectInteger) {
return objectInteger
}
case .Real:
// Real
var objectReal = CGPDFReal()
if CGPDFObjectGetValue(object, objectType, &objectReal) {
return objectReal
}
case .String:
let valueFound = CGPDFObjectGetValue(object, objectType, &ptrObjectValue)
let stringValue = CGPDFStringCopyTextString(COpaquePointer(ptrObjectValue))
return stringValue
case .Dictionary:
// Dictionary
var objectDictionary = CGPDFDictionaryRef()
if (CGPDFObjectGetValue(object, objectType, &objectDictionary)) {
let count = CGPDFDictionaryGetCount(objectDictionary)
print("In array, found dictionary with \(count) entries")
CGPDFDictionaryApplyFunction(objectDictionary, printPDFKeys, nil)
}
case .Stream:
// Stream
var objectStream = CGPDFStreamRef()
if (CGPDFObjectGetValue(object, objectType, &objectStream)) {
let dict: CGPDFDictionaryRef = CGPDFStreamGetDictionary( objectStream )
var fmt: CGPDFDataFormat = .Raw
let streamData: CFDataRef = CGPDFStreamCopyData(objectStream, &fmt)!;
let data = NSData(data: streamData)
let dataString = NSString(data: data, encoding: NSUTF8StringEncoding)
print("data stream (length=\(CFDataGetLength(streamData))):")
return dataString
}
default:
return nil
}
return nil
}

Answer 3

Made a parser (based on previous answers) that crawls the PDF hierarchy and gives you a JSON.
// Parse PDF into JSON.
PDFParser.parse(pdfUrl: pdfFileURL, into: jsonFileURL)
// Parse PDF into Dictionary.
let pdf: [String:Any?] = PDFParser.parse(pdfUrl: pdfFileURL)
Gives you:
{
"Catalog" : {
"Pages<Dictionary>" : {
"MediaBox<Array>" : [
0,
0,
612,
792
],
"Type<Name>" : "Pages",
"Kids<Array>" : [
{
"Rotate<Integer>" : 0,
"MediaBox<Array>" : [
0,
0,
595.27499999999998,
841.88999999999999
],
"Parent<Dictionary>" : "<PARENT_NOT_SERIALIZED>",
"Resources<Dictionary>" : {
"ColorSpace<Dictionary>" : {
"Cs1<Array>" : [
"ICCBased",
{
"N<Integer>" : 3,
"Filter<Name>" : "FlateDecode",
"Alternate<Name>" : "DeviceRGB",
"Length<Integer>" : 2612
}
]
}
...
To get from CGPDFDocument (like original question):
// Get document catalog.
guard
let document = CGPDFDocument(pdfFileURL as CFURL),
let catalog = document.catalog
else { return }
// Parse into dictionary.
let catalogDictionary = PDFParser.value(from: catalog)
Gives you a pretty usual Swift dictionary. Console output:
Optional(["Pages<Dictionary>": Optional({
"Count<Integer>" = 1;
"Kids<Array>" = (
{
"ArtBox<Array>" = (
"28.3465",
"325.193",
"393.389",
"813.543"
);
"Contents<Stream>" = {
Data = "q Q q 0 0 595.276 841.89 re W n 1 0 1 0 k /Gs1 gs 201.8862 420.9449 m 201.8862\n473.8269 244.7562 516.6959 297.6372 516.6959 c 350.5192 516.6959 393.3892\n473.8269 393.3892 420.9449 c 393.3892 368.0629 350.5192 325.1939 297.6372\n325.1939 c 244.7562 325.1939 201.8862 368.0629 201.8862 420.9449 c f Q q 28.346 530.078 283.464 283.465\nre W n 0 0 0 1 k /Gs1 gs BT 12 0 0 12 28.3467 803.499 Tm /Tc1 1 Tf [ (h) 4\n(ttp://epp) 7 (z.eu) ] TJ ET Q";
"Filter<Name>" = FlateDecode;
"Length<Integer>" = 237;
};
"MediaBox<Array>" = (
0,
0,
"595.2760000000001",
"841.89"
);
"Parent<Dictionary>" = "<PARENT_NOT_SERIALIZED>";
"Resources<Dictionary>" = {
"ExtGState<Dictionary>" = {
"Gs1<Dictionary>" = {
"OPM<Integer>" = 1;
"Type<Name>" = ExtGState;
};
};
...
ParsePDF.swift:
//
// PDFParser.swift
// PDFParser
//
// Copyright (c) 2020 Geri Borbás http://www.twitter.com/_eppz
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
import Foundation
import PDFKit
class PDFParser
{
/// Shorthand for type strings.
static let namesForTypes: [CGPDFObjectType:String] =
[
.null : "Null",
.boolean : "Boolean",
.integer : "Integer",
.real : "Real",
.name : "Name",
.string : "String",
.array : "Array",
.dictionary : "Dictionary",
.stream : "Stream",
CGPDFObjectTypeObject : "Object",
]
struct Message
{
static let parentNotSerialized = "<PARENT_NOT_SERIALIZED>"
static let couldNotParseValue = "<COULD_NOT_PARSE_VALUE>"
static let couldNotGetStreamData = "<COULD_NOT_GET_STREAM_DATA>"
static let unknownStreamDataFormat = "<UNKNOWN_STREAM_DATA_FORMAT>"
}
/// Parse a PDF file into a JSON file.
static func parse(pdfUrl: URL, into jsonURL: URL)
{
do
{
let pdf = PDFParser.parse(pdfUrl: pdfUrl)
let data = try JSONSerialization.data(withJSONObject: pdf, options: .prettyPrinted)
try data.write(to: jsonURL, options: [])
}
catch
{ print(error) }
}
/// Parse a PDF file into a JSON file.
static func parse(pdfUrl: URL) -> [String:Any?]
{
// Document.
guard
let document = CGPDFDocument(pdfUrl as CFURL),
let catalog = document.catalog,
let info = document.info
else
{
print("Cannot open PDF.")
return [:]
}
// Parse.
return [
"Catalog" : PDFParser.value(from: catalog),
"Info" : PDFParser.value(from: info)
]
}
static func value(from object: CGPDFObjectRef) -> Any?
{
switch (CGPDFObjectGetType(object))
{
case .null:
return nil
case .boolean:
var valueRef: CGPDFBoolean = 0
if CGPDFObjectGetValue(object, .boolean, &valueRef)
{ return Bool(valueRef == 0x01) }
case .integer:
var valueRef: CGPDFInteger = 0
if CGPDFObjectGetValue(object, .integer, &valueRef)
{ return valueRef as Int }
case .real:
var valueRef: CGPDFReal = 0.0
if CGPDFObjectGetValue(object, .real, &valueRef)
{ return Double(valueRef) }
case .name:
var objectRefOrNil: UnsafePointer<Int8>? = nil
if
CGPDFObjectGetValue(object, .name, &objectRefOrNil),
let objectRef = objectRefOrNil,
let string = String(cString: objectRef, encoding: String.Encoding.isoLatin1)
{ return string }
case .string:
var objectRefOrNil: UnsafePointer<Int8>? = nil
if
CGPDFObjectGetValue(object, .string, &objectRefOrNil),
let objectRef = objectRefOrNil,
let stringRef = CGPDFStringCopyTextString(OpaquePointer(objectRef))
{ return stringRef as String }
case .array:
var arrayRefOrNil: CGPDFArrayRef? = nil
if
CGPDFObjectGetValue(object, .array, &arrayRefOrNil),
let arrayRef = arrayRefOrNil
{
var array: [Any] = []
for index in 0 ..< CGPDFArrayGetCount(arrayRef)
{
var eachObjectRef: CGPDFObjectRef? = nil
if
CGPDFArrayGetObject(arrayRef, index, &eachObjectRef),
let eachObject = eachObjectRef,
let eachValue = PDFParser.value(from: eachObject)
{ array.append(eachValue) }
}
return array
}
case .stream:
var streamRefOrNil: CGPDFStreamRef? = nil
if
CGPDFObjectGetValue(object, .stream, &streamRefOrNil),
let streamRef = streamRefOrNil,
let streamDictionaryRef = CGPDFStreamGetDictionary(streamRef)
{
// Get stream dictionary.
var streamNSMutableDictionary = NSMutableDictionary()
Self.collectObjects(from: streamDictionaryRef, into: &streamNSMutableDictionary)
var streamDictionary = streamNSMutableDictionary as! [String: Any?]
// Get data.
var dataString: String? = Message.couldNotGetStreamData
var streamDataFormat: CGPDFDataFormat = .raw
if let streamData: CFData = CGPDFStreamCopyData(streamRef, &streamDataFormat)
{
switch streamDataFormat
{
case .raw: dataString = String(data: NSData(data: streamData as Data) as Data, encoding: String.Encoding.utf8)
case .jpegEncoded, .JPEG2000: dataString = NSData(data: streamData as Data).base64EncodedString()
#unknown default: dataString = Message.unknownStreamDataFormat
}
}
// Add to dictionary.
streamDictionary["Data"] = dataString
return streamDictionary
}
case .dictionary:
var dictionaryRefOrNil: CGPDFDictionaryRef? = nil
if
CGPDFObjectGetValue(object, .dictionary, &dictionaryRefOrNil),
let dictionaryRef = dictionaryRefOrNil
{
var dictionary = NSMutableDictionary()
Self.collectObjects(from: dictionaryRef, into: &dictionary)
return dictionary as! [String: Any?]
}
#unknown default:
var dictionary = NSMutableDictionary()
Self.collectObjects(from: object, into: &dictionary)
return dictionary as! [String: Any?]
}
// No known case.
return nil
}
static func collectObjects(from dictionaryRef: CGPDFDictionaryRef, into dictionaryPointer: UnsafeMutableRawPointer?)
{
CGPDFDictionaryApplyFunction(
dictionaryRef,
{
(eachKeyPointer, eachObject, eachContextOrNil: UnsafeMutableRawPointer?) -> Void in
// Unwrap dictionary.
guard let dictionary = eachContextOrNil?.assumingMemoryBound(to: NSMutableDictionary.self).pointee
else { return print("Could not unwrap dictionary.") }
// Unwrap key.
guard let eachKey = String(cString: UnsafePointer<CChar>(eachKeyPointer), encoding: .isoLatin1)
else { return print("Could not unwrap key.") }
// Type.
guard let eachTypeName = PDFParser.namesForTypes[CGPDFObjectGetType(eachObject)]
else { return print("Could not unwrap type.") }
// Assemble.
let eachDictionaryKey = "\(eachKey)<\(eachTypeName)>" as NSString
// Skip parent.
guard eachKey != "Parent"
else
{
dictionary.setObject(Message.parentNotSerialized, forKey: eachDictionaryKey)
return
}
// Parse value.
guard let eachValue = PDFParser.value(from: eachObject)
else
{
dictionary.setObject(Message.couldNotParseValue, forKey: eachDictionaryKey)
fatalError("😭")
// return
}
// Set.
dictionary.setObject(eachValue, forKey: eachDictionaryKey)
},
dictionaryPointer
)
}
}