michael@0: 
michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkPDFCatalog.h"
michael@0: #include "SkPDFDevice.h"
michael@0: #include "SkPDFDocument.h"
michael@0: #include "SkPDFFont.h"
michael@0: #include "SkPDFPage.h"
michael@0: #include "SkPDFTypes.h"
michael@0: #include "SkStream.h"
michael@0: #include "SkTSet.h"
michael@0: 
michael@0: static void addResourcesToCatalog(bool firstPage,
michael@0:                                   SkTSet<SkPDFObject*>* resourceSet,
michael@0:                                   SkPDFCatalog* catalog) {
michael@0:     for (int i = 0; i < resourceSet->count(); i++) {
michael@0:         catalog->addObject((*resourceSet)[i], firstPage);
michael@0:     }
michael@0: }
michael@0: 
michael@0: static void perform_font_subsetting(SkPDFCatalog* catalog,
michael@0:                                     const SkTDArray<SkPDFPage*>& pages,
michael@0:                                     SkTDArray<SkPDFObject*>* substitutes) {
michael@0:     SkASSERT(catalog);
michael@0:     SkASSERT(substitutes);
michael@0: 
michael@0:     SkPDFGlyphSetMap usage;
michael@0:     for (int i = 0; i < pages.count(); ++i) {
michael@0:         usage.merge(pages[i]->getFontGlyphUsage());
michael@0:     }
michael@0:     SkPDFGlyphSetMap::F2BIter iterator(usage);
michael@0:     const SkPDFGlyphSetMap::FontGlyphSetPair* entry = iterator.next();
michael@0:     while (entry) {
michael@0:         SkPDFFont* subsetFont =
michael@0:             entry->fFont->getFontSubset(entry->fGlyphSet);
michael@0:         if (subsetFont) {
michael@0:             catalog->setSubstitute(entry->fFont, subsetFont);
michael@0:             substitutes->push(subsetFont);  // Transfer ownership to substitutes
michael@0:         }
michael@0:         entry = iterator.next();
michael@0:     }
michael@0: }
michael@0: 
michael@0: SkPDFDocument::SkPDFDocument(Flags flags)
michael@0:         : fXRefFileOffset(0),
michael@0:           fTrailerDict(NULL) {
michael@0:     fCatalog.reset(new SkPDFCatalog(flags));
michael@0:     fDocCatalog = SkNEW_ARGS(SkPDFDict, ("Catalog"));
michael@0:     fCatalog->addObject(fDocCatalog, true);
michael@0:     fFirstPageResources = NULL;
michael@0:     fOtherPageResources = NULL;
michael@0: }
michael@0: 
michael@0: SkPDFDocument::~SkPDFDocument() {
michael@0:     fPages.safeUnrefAll();
michael@0: 
michael@0:     // The page tree has both child and parent pointers, so it creates a
michael@0:     // reference cycle.  We must clear that cycle to properly reclaim memory.
michael@0:     for (int i = 0; i < fPageTree.count(); i++) {
michael@0:         fPageTree[i]->clear();
michael@0:     }
michael@0:     fPageTree.safeUnrefAll();
michael@0: 
michael@0:     if (fFirstPageResources) {
michael@0:         fFirstPageResources->safeUnrefAll();
michael@0:     }
michael@0:     if (fOtherPageResources) {
michael@0:         fOtherPageResources->safeUnrefAll();
michael@0:     }
michael@0: 
michael@0:     fSubstitutes.safeUnrefAll();
michael@0: 
michael@0:     fDocCatalog->unref();
michael@0:     SkSafeUnref(fTrailerDict);
michael@0:     SkDELETE(fFirstPageResources);
michael@0:     SkDELETE(fOtherPageResources);
michael@0: }
michael@0: 
michael@0: bool SkPDFDocument::emitPDF(SkWStream* stream) {
michael@0:     if (fPages.isEmpty()) {
michael@0:         return false;
michael@0:     }
michael@0:     for (int i = 0; i < fPages.count(); i++) {
michael@0:         if (fPages[i] == NULL) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     fFirstPageResources = SkNEW(SkTSet<SkPDFObject*>);
michael@0:     fOtherPageResources = SkNEW(SkTSet<SkPDFObject*>);
michael@0: 
michael@0:     // We haven't emitted the document before if fPageTree is empty.
michael@0:     if (fPageTree.isEmpty()) {
michael@0:         SkPDFDict* pageTreeRoot;
michael@0:         SkPDFPage::GeneratePageTree(fPages, fCatalog.get(), &fPageTree,
michael@0:                                     &pageTreeRoot);
michael@0:         fDocCatalog->insert("Pages", new SkPDFObjRef(pageTreeRoot))->unref();
michael@0: 
michael@0:         /* TODO(vandebo): output intent
michael@0:         SkAutoTUnref<SkPDFDict> outputIntent = new SkPDFDict("OutputIntent");
michael@0:         outputIntent->insert("S", new SkPDFName("GTS_PDFA1"))->unref();
michael@0:         outputIntent->insert("OutputConditionIdentifier",
michael@0:                              new SkPDFString("sRGB"))->unref();
michael@0:         SkAutoTUnref<SkPDFArray> intentArray = new SkPDFArray;
michael@0:         intentArray->append(outputIntent.get());
michael@0:         fDocCatalog->insert("OutputIntent", intentArray.get());
michael@0:         */
michael@0: 
michael@0:         SkAutoTUnref<SkPDFDict> dests(SkNEW(SkPDFDict));
michael@0: 
michael@0:         bool firstPage = true;
michael@0:         /* The references returned in newResources are transfered to
michael@0:          * fFirstPageResources or fOtherPageResources depending on firstPage and
michael@0:          * knownResources doesn't have a reference but just relies on the other
michael@0:          * two sets to maintain a reference.
michael@0:          */
michael@0:         SkTSet<SkPDFObject*> knownResources;
michael@0: 
michael@0:         // mergeInto returns the number of duplicates.
michael@0:         // If there are duplicates, there is a bug and we mess ref counting.
michael@0:         SkDEBUGCODE(int duplicates =) knownResources.mergeInto(*fFirstPageResources);
michael@0:         SkASSERT(duplicates == 0);
michael@0: 
michael@0:         for (int i = 0; i < fPages.count(); i++) {
michael@0:             if (i == 1) {
michael@0:                 firstPage = false;
michael@0:                 SkDEBUGCODE(duplicates =) knownResources.mergeInto(*fOtherPageResources);
michael@0:             }
michael@0:             SkTSet<SkPDFObject*> newResources;
michael@0:             fPages[i]->finalizePage(
michael@0:                 fCatalog.get(), firstPage, knownResources, &newResources);
michael@0:             addResourcesToCatalog(firstPage, &newResources, fCatalog.get());
michael@0:             if (firstPage) {
michael@0:                 SkDEBUGCODE(duplicates =) fFirstPageResources->mergeInto(newResources);
michael@0:             } else {
michael@0:                 SkDEBUGCODE(duplicates =) fOtherPageResources->mergeInto(newResources);
michael@0:             }
michael@0:             SkASSERT(duplicates == 0);
michael@0: 
michael@0:             SkDEBUGCODE(duplicates =) knownResources.mergeInto(newResources);
michael@0:             SkASSERT(duplicates == 0);
michael@0: 
michael@0:             fPages[i]->appendDestinations(dests);
michael@0:         }
michael@0: 
michael@0:         if (dests->size() > 0) {
michael@0:             SkPDFDict* raw_dests = dests.get();
michael@0:             fFirstPageResources->add(dests.detach());  // Transfer ownership.
michael@0:             fCatalog->addObject(raw_dests, true /* onFirstPage */);
michael@0:             fDocCatalog->insert("Dests", SkNEW_ARGS(SkPDFObjRef, (raw_dests)))->unref();
michael@0:         }
michael@0: 
michael@0:         // Build font subsetting info before proceeding.
michael@0:         perform_font_subsetting(fCatalog.get(), fPages, &fSubstitutes);
michael@0: 
michael@0:         // Figure out the size of things and inform the catalog of file offsets.
michael@0:         off_t fileOffset = headerSize();
michael@0:         fileOffset += fCatalog->setFileOffset(fDocCatalog, fileOffset);
michael@0:         fileOffset += fCatalog->setFileOffset(fPages[0], fileOffset);
michael@0:         fileOffset += fPages[0]->getPageSize(fCatalog.get(),
michael@0:                 (size_t) fileOffset);
michael@0:         for (int i = 0; i < fFirstPageResources->count(); i++) {
michael@0:             fileOffset += fCatalog->setFileOffset((*fFirstPageResources)[i],
michael@0:                                                   fileOffset);
michael@0:         }
michael@0:         // Add the size of resources of substitute objects used on page 1.
michael@0:         fileOffset += fCatalog->setSubstituteResourcesOffsets(fileOffset, true);
michael@0:         if (fPages.count() > 1) {
michael@0:             // TODO(vandebo): For linearized format, save the start of the
michael@0:             // first page xref table and calculate the size.
michael@0:         }
michael@0: 
michael@0:         for (int i = 0; i < fPageTree.count(); i++) {
michael@0:             fileOffset += fCatalog->setFileOffset(fPageTree[i], fileOffset);
michael@0:         }
michael@0: 
michael@0:         for (int i = 1; i < fPages.count(); i++) {
michael@0:             fileOffset += fPages[i]->getPageSize(fCatalog.get(), fileOffset);
michael@0:         }
michael@0: 
michael@0:         for (int i = 0; i < fOtherPageResources->count(); i++) {
michael@0:             fileOffset += fCatalog->setFileOffset(
michael@0:                 (*fOtherPageResources)[i], fileOffset);
michael@0:         }
michael@0: 
michael@0:         fileOffset += fCatalog->setSubstituteResourcesOffsets(fileOffset,
michael@0:                                                               false);
michael@0:         fXRefFileOffset = fileOffset;
michael@0:     }
michael@0: 
michael@0:     emitHeader(stream);
michael@0:     fDocCatalog->emitObject(stream, fCatalog.get(), true);
michael@0:     fPages[0]->emitObject(stream, fCatalog.get(), true);
michael@0:     fPages[0]->emitPage(stream, fCatalog.get());
michael@0:     for (int i = 0; i < fFirstPageResources->count(); i++) {
michael@0:         (*fFirstPageResources)[i]->emit(stream, fCatalog.get(), true);
michael@0:     }
michael@0:     fCatalog->emitSubstituteResources(stream, true);
michael@0:     // TODO(vandebo): Support linearized format
michael@0:     // if (fPages.size() > 1) {
michael@0:     //     // TODO(vandebo): Save the file offset for the first page xref table.
michael@0:     //     fCatalog->emitXrefTable(stream, true);
michael@0:     // }
michael@0: 
michael@0:     for (int i = 0; i < fPageTree.count(); i++) {
michael@0:         fPageTree[i]->emitObject(stream, fCatalog.get(), true);
michael@0:     }
michael@0: 
michael@0:     for (int i = 1; i < fPages.count(); i++) {
michael@0:         fPages[i]->emitPage(stream, fCatalog.get());
michael@0:     }
michael@0: 
michael@0:     for (int i = 0; i < fOtherPageResources->count(); i++) {
michael@0:         (*fOtherPageResources)[i]->emit(stream, fCatalog.get(), true);
michael@0:     }
michael@0: 
michael@0:     fCatalog->emitSubstituteResources(stream, false);
michael@0:     int64_t objCount = fCatalog->emitXrefTable(stream, fPages.count() > 1);
michael@0:     emitFooter(stream, objCount);
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool SkPDFDocument::setPage(int pageNumber, SkPDFDevice* pdfDevice) {
michael@0:     if (!fPageTree.isEmpty()) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     pageNumber--;
michael@0:     SkASSERT(pageNumber >= 0);
michael@0: 
michael@0:     if (pageNumber >= fPages.count()) {
michael@0:         int oldSize = fPages.count();
michael@0:         fPages.setCount(pageNumber + 1);
michael@0:         for (int i = oldSize; i <= pageNumber; i++) {
michael@0:             fPages[i] = NULL;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     SkPDFPage* page = new SkPDFPage(pdfDevice);
michael@0:     SkSafeUnref(fPages[pageNumber]);
michael@0:     fPages[pageNumber] = page;  // Reference from new passed to fPages.
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: bool SkPDFDocument::appendPage(SkPDFDevice* pdfDevice) {
michael@0:     if (!fPageTree.isEmpty()) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     SkPDFPage* page = new SkPDFPage(pdfDevice);
michael@0:     fPages.push(page);  // Reference from new passed to fPages.
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: void SkPDFDocument::getCountOfFontTypes(
michael@0:         int counts[SkAdvancedTypefaceMetrics::kNotEmbeddable_Font + 1]) const {
michael@0:     sk_bzero(counts, sizeof(int) *
michael@0:                      (SkAdvancedTypefaceMetrics::kNotEmbeddable_Font + 1));
michael@0:     SkTDArray<SkFontID> seenFonts;
michael@0: 
michael@0:     for (int pageNumber = 0; pageNumber < fPages.count(); pageNumber++) {
michael@0:         const SkTDArray<SkPDFFont*>& fontResources =
michael@0:                 fPages[pageNumber]->getFontResources();
michael@0:         for (int font = 0; font < fontResources.count(); font++) {
michael@0:             SkFontID fontID = fontResources[font]->typeface()->uniqueID();
michael@0:             if (seenFonts.find(fontID) == -1) {
michael@0:                 counts[fontResources[font]->getType()]++;
michael@0:                 seenFonts.push(fontID);
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: void SkPDFDocument::emitHeader(SkWStream* stream) {
michael@0:     stream->writeText("%PDF-1.4\n%");
michael@0:     // The PDF spec recommends including a comment with four bytes, all
michael@0:     // with their high bits set.  This is "Skia" with the high bits set.
michael@0:     stream->write32(0xD3EBE9E1);
michael@0:     stream->writeText("\n");
michael@0: }
michael@0: 
michael@0: size_t SkPDFDocument::headerSize() {
michael@0:     SkDynamicMemoryWStream buffer;
michael@0:     emitHeader(&buffer);
michael@0:     return buffer.getOffset();
michael@0: }
michael@0: 
michael@0: void SkPDFDocument::emitFooter(SkWStream* stream, int64_t objCount) {
michael@0:     if (NULL == fTrailerDict) {
michael@0:         fTrailerDict = SkNEW(SkPDFDict);
michael@0: 
michael@0:         // TODO(vandebo): Linearized format will take a Prev entry too.
michael@0:         // TODO(vandebo): PDF/A requires an ID entry.
michael@0:         fTrailerDict->insertInt("Size", int(objCount));
michael@0:         fTrailerDict->insert("Root", new SkPDFObjRef(fDocCatalog))->unref();
michael@0:     }
michael@0: 
michael@0:     stream->writeText("trailer\n");
michael@0:     fTrailerDict->emitObject(stream, fCatalog.get(), false);
michael@0:     stream->writeText("\nstartxref\n");
michael@0:     stream->writeBigDecAsText(fXRefFileOffset);
michael@0:     stream->writeText("\n%%EOF");
michael@0: }