SkDocument base for pdf, xps, etc.

R=scroggo@google.com

Review URL: https://codereview.chromium.org/16660002

git-svn-id: http://skia.googlecode.com/svn/trunk@9476 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/doc/SkDocument_PDF.cpp b/src/doc/SkDocument_PDF.cpp
new file mode 100644
index 0000000..3d9c463
--- /dev/null
+++ b/src/doc/SkDocument_PDF.cpp
@@ -0,0 +1,92 @@
+/*
+ * Copyright 2013 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkDocument.h"
+#include "SkPDFDocument.h"
+#include "SkPDFDevice.h"
+
+class SkDocument_PDF : public SkDocument {
+public:
+    SkDocument_PDF(SkWStream* stream, void (*doneProc)(SkWStream*))
+            : SkDocument(stream, doneProc) {
+        fDoc = SkNEW(SkPDFDocument);
+        fCanvas = NULL;
+        fDevice = NULL;
+    }
+    
+    virtual ~SkDocument_PDF() {
+        // subclasses must call close() in their destructors
+        this->close();
+    }
+
+protected:
+    virtual SkCanvas* onBeginPage(SkScalar width, SkScalar height,
+                                  const SkRect& content) SK_OVERRIDE {
+        SkASSERT(NULL == fCanvas);
+        SkASSERT(NULL == fDevice);
+
+        SkISize pageS, contentS;
+        SkMatrix matrix;
+
+        pageS.set(SkScalarRoundToInt(width), SkScalarRoundToInt(height));
+        contentS.set(SkScalarRoundToInt(content.width()),
+                     SkScalarRoundToInt(content.height()));
+        matrix.setTranslate(content.fLeft, content.fTop);
+
+        fDevice = SkNEW_ARGS(SkPDFDevice, (pageS, contentS, matrix));
+        fCanvas = SkNEW_ARGS(SkCanvas, (fDevice));
+        return fCanvas;
+    }
+
+    virtual void onEndPage() SK_OVERRIDE {
+        SkASSERT(fCanvas);
+        SkASSERT(fDevice);
+
+        fCanvas->flush();
+        fDoc->appendPage(fDevice);
+
+        fCanvas->unref();
+        fDevice->unref();
+
+        fCanvas = NULL;
+        fDevice = NULL;
+    }
+
+    virtual void onClose(SkWStream* stream) SK_OVERRIDE {
+        SkASSERT(NULL == fCanvas);
+        SkASSERT(NULL == fDevice);
+
+        fDoc->emitPDF(stream);
+        SkDELETE(fDoc);
+        fDoc = NULL;
+    }
+
+private:
+    SkPDFDocument*  fDoc;
+    SkPDFDevice*    fDevice;
+    SkCanvas*       fCanvas;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkDocument* SkDocument::CreatePDF(SkWStream* stream, void (*done)(SkWStream*)) {
+    return stream ? SkNEW_ARGS(SkDocument_PDF, (stream, done)) : NULL;
+}
+
+static void delete_wstream(SkWStream* stream) {
+    SkDELETE(stream);
+}
+
+SkDocument* SkDocument::CreatePDF(const char path[]) {
+    SkFILEWStream* stream = SkNEW_ARGS(SkFILEWStream, (path));
+    if (!stream->isValid()) {
+        SkDELETE(stream);
+        return NULL;
+    }
+    return SkNEW_ARGS(SkDocument_PDF, (stream, delete_wstream));
+}
+