move BrowserFontResource_Trusted to content/child

Needed to break dependency of ppapi_proxy on webkit code.

resource_creation_proxy now creates BrowserFontResource_Trusted
by going through PluginGlobals -> PluginProxyDelegate implemented
in content by PpapiThread.

R=jam@chromium.org, yzshen@chromium.org
BUG=237249

Review URL: https://codereview.chromium.org/20214004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@213684 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 428 insertions, 0 deletions

diff --git a/content/child/browser_font_resource_trusted.cc b/content/child/browser_font_resource_trusted.cc
new file mode 100644
index 0000000..d31ede0
--- /dev/null
+++ b/content/child/browser_font_resource_trusted.cc
@@ -0,0 +1,428 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/child/browser_font_resource_trusted.h"
+
+#include "base/strings/string_util.h"
+#include "base/strings/utf_string_conversions.h"
+#include "ppapi/c/dev/ppb_font_dev.h"
+#include "ppapi/proxy/connection.h"
+#include "ppapi/shared_impl/ppapi_preferences.h"
+#include "ppapi/shared_impl/var.h"
+#include "ppapi/thunk/enter.h"
+#include "ppapi/thunk/ppb_image_data_api.h"
+#include "ppapi/thunk/thunk.h"
+#include "skia/ext/platform_canvas.h"
+#include "third_party/WebKit/public/platform/WebCanvas.h"
+#include "third_party/WebKit/public/platform/WebFloatPoint.h"
+#include "third_party/WebKit/public/platform/WebFloatRect.h"
+#include "third_party/WebKit/public/platform/WebRect.h"
+#include "third_party/WebKit/public/web/WebFont.h"
+#include "third_party/WebKit/public/web/WebFontDescription.h"
+#include "third_party/WebKit/public/web/WebTextRun.h"
+#include "third_party/icu/source/common/unicode/ubidi.h"
+#include "third_party/skia/include/core/SkRect.h"
+
+using ppapi::StringVar;
+using ppapi::thunk::EnterResourceNoLock;
+using ppapi::thunk::PPB_ImageData_API;
+using WebKit::WebFloatPoint;
+using WebKit::WebFloatRect;
+using WebKit::WebFont;
+using WebKit::WebFontDescription;
+using WebKit::WebRect;
+using WebKit::WebTextRun;
+using WebKit::WebCanvas;
+
+namespace content {
+
+namespace {
+
+// Same as WebPreferences::kCommonScript. I'd use that directly here, but get an
+// undefined reference linker error.
+const char kCommonScript[] = "Zyyy";
+
+string16 GetFontFromMap(
+    const webkit_glue::ScriptFontFamilyMap& map,
+    const std::string& script) {
+  webkit_glue::ScriptFontFamilyMap::const_iterator it =
+      map.find(script);
+  if (it != map.end())
+    return it->second;
+  return string16();
+}
+
+// Splits a PP_BrowserFont_Trusted_TextRun into a sequence or LTR and RTL
+// WebTextRuns that can be used for WebKit. Normally WebKit does this for us,
+// but the font drawing and measurement routines we call happen after this
+// step. So for correct rendering of RTL content, we need to do it ourselves.
+class TextRunCollection {
+ public:
+  explicit TextRunCollection(const PP_BrowserFont_Trusted_TextRun& run)
+      : bidi_(NULL),
+        num_runs_(0) {
+    StringVar* text_string = StringVar::FromPPVar(run.text);
+    if (!text_string)
+      return;  // Leave num_runs_ = 0 so we'll do nothing.
+    text_ = UTF8ToUTF16(text_string->value());
+
+    if (run.override_direction) {
+      // Skip autodetection.
+      num_runs_ = 1;
+      override_run_ = WebTextRun(text_, PP_ToBool(run.rtl), true);
+    } else {
+      bidi_ = ubidi_open();
+      UErrorCode uerror = U_ZERO_ERROR;
+      ubidi_setPara(bidi_, text_.data(), text_.size(), run.rtl, NULL, &uerror);
+      if (U_SUCCESS(uerror))
+        num_runs_ = ubidi_countRuns(bidi_, &uerror);
+    }
+  }
+
+  ~TextRunCollection() {
+    if (bidi_)
+      ubidi_close(bidi_);
+  }
+
+  const string16& text() const { return text_; }
+  int num_runs() const { return num_runs_; }
+
+  // Returns a WebTextRun with the info for the run at the given index.
+  // The range covered by the run is in the two output params.
+  WebTextRun GetRunAt(int index, int32_t* run_start, int32_t* run_len) const {
+    DCHECK(index < num_runs_);
+    if (bidi_) {
+      bool run_rtl = !!ubidi_getVisualRun(bidi_, index, run_start, run_len);
+      return WebTextRun(string16(&text_[*run_start], *run_len),
+                        run_rtl, true);
+    }
+
+    // Override run, return the single one.
+    DCHECK(index == 0);
+    *run_start = 0;
+    *run_len = static_cast<int32_t>(text_.size());
+    return override_run_;
+  }
+
+ private:
+  // Will be null if we skipped autodetection.
+  UBiDi* bidi_;
+
+  // Text of all the runs.
+  string16 text_;
+
+  int num_runs_;
+
+  // When the content specifies override_direction (bidi_ is null) then this
+  // will contain the single text run for WebKit.
+  WebTextRun override_run_;
+
+  DISALLOW_COPY_AND_ASSIGN(TextRunCollection);
+};
+
+bool PPTextRunToWebTextRun(const PP_BrowserFont_Trusted_TextRun& text,
+                           WebTextRun* run) {
+  StringVar* text_string = StringVar::FromPPVar(text.text);
+  if (!text_string)
+    return false;
+
+  *run = WebTextRun(UTF8ToUTF16(text_string->value()),
+                    PP_ToBool(text.rtl),
+                    PP_ToBool(text.override_direction));
+  return true;
+}
+
+// The PP_* version lacks "None", so is just one value shifted from the
+// WebFontDescription version. These values are checked in
+// PPFontDescToWebFontDesc to make sure the conversion is correct. This is a
+// macro so it can also be used in the COMPILE_ASSERTS.
+#define PP_FAMILY_TO_WEB_FAMILY(f) \
+  static_cast<WebFontDescription::GenericFamily>(f + 1)
+
+// Assumes the given PP_FontDescription has been validated.
+WebFontDescription PPFontDescToWebFontDesc(
+    const PP_BrowserFont_Trusted_Description& font,
+    const ppapi::Preferences& prefs) {
+  // Verify that the enums match so we can just static cast.
+  COMPILE_ASSERT(static_cast<int>(WebFontDescription::Weight100) ==
+                 static_cast<int>(PP_BROWSERFONT_TRUSTED_WEIGHT_100),
+                 FontWeight100);
+  COMPILE_ASSERT(static_cast<int>(WebFontDescription::Weight900) ==
+                 static_cast<int>(PP_BROWSERFONT_TRUSTED_WEIGHT_900),
+                 FontWeight900);
+  COMPILE_ASSERT(WebFontDescription::GenericFamilyStandard ==
+                 PP_FAMILY_TO_WEB_FAMILY(PP_FONTFAMILY_DEFAULT),
+                 StandardFamily);
+  COMPILE_ASSERT(WebFontDescription::GenericFamilySerif ==
+                 PP_FAMILY_TO_WEB_FAMILY(PP_FONTFAMILY_SERIF),
+                 SerifFamily);
+  COMPILE_ASSERT(WebFontDescription::GenericFamilySansSerif ==
+                 PP_FAMILY_TO_WEB_FAMILY(PP_FONTFAMILY_SANSSERIF),
+                 SansSerifFamily);
+  COMPILE_ASSERT(WebFontDescription::GenericFamilyMonospace ==
+                 PP_FAMILY_TO_WEB_FAMILY(PP_FONTFAMILY_MONOSPACE),
+                 MonospaceFamily);
+
+  StringVar* face_name = StringVar::FromPPVar(font.face);  // Possibly null.
+
+  WebFontDescription result;
+  string16 resolved_family;
+  if (!face_name || face_name->value().empty()) {
+    // Resolve the generic family.
+    switch (font.family) {
+      case PP_BROWSERFONT_TRUSTED_FAMILY_SERIF:
+        resolved_family = GetFontFromMap(prefs.serif_font_family_map,
+                                         kCommonScript);
+        break;
+      case PP_BROWSERFONT_TRUSTED_FAMILY_SANSSERIF:
+        resolved_family = GetFontFromMap(prefs.sans_serif_font_family_map,
+                                         kCommonScript);
+        break;
+      case PP_BROWSERFONT_TRUSTED_FAMILY_MONOSPACE:
+        resolved_family = GetFontFromMap(prefs.fixed_font_family_map,
+                                         kCommonScript);
+        break;
+      case PP_BROWSERFONT_TRUSTED_FAMILY_DEFAULT:
+      default:
+        resolved_family = GetFontFromMap(prefs.standard_font_family_map,
+                                         kCommonScript);
+        break;
+    }
+  } else {
+    // Use the exact font.
+    resolved_family = UTF8ToUTF16(face_name->value());
+  }
+  result.family = resolved_family;
+
+  result.genericFamily = PP_FAMILY_TO_WEB_FAMILY(font.family);
+
+  if (font.size == 0) {
+    // Resolve the default font size, using the resolved family to see if
+    // we should use the fixed or regular font size. It's difficult at this
+    // level to detect if the requested font is fixed width, so we only apply
+    // the alternate font size to the default fixed font family.
+    if (StringToLowerASCII(resolved_family) ==
+        StringToLowerASCII(GetFontFromMap(prefs.fixed_font_family_map,
+                                          kCommonScript)))
+      result.size = static_cast<float>(prefs.default_fixed_font_size);
+    else
+      result.size = static_cast<float>(prefs.default_font_size);
+  } else {
+    // Use the exact size.
+    result.size = static_cast<float>(font.size);
+  }
+
+  result.italic = font.italic != PP_FALSE;
+  result.smallCaps = font.small_caps != PP_FALSE;
+  result.weight = static_cast<WebFontDescription::Weight>(font.weight);
+  result.letterSpacing = static_cast<short>(font.letter_spacing);
+  result.wordSpacing = static_cast<short>(font.word_spacing);
+  return result;
+}
+
+}  // namespace
+
+// static
+bool BrowserFontResource_Trusted::IsPPFontDescriptionValid(
+    const PP_BrowserFont_Trusted_Description& desc) {
+  // Check validity of string. We can't check the actual text since we could
+  // be on the wrong thread and don't know if we're in the plugin or the host.
+  if (desc.face.type != PP_VARTYPE_STRING &&
+      desc.face.type != PP_VARTYPE_UNDEFINED)
+    return false;
+
+  // Check enum ranges.
+  if (static_cast<int>(desc.family) < PP_BROWSERFONT_TRUSTED_FAMILY_DEFAULT ||
+      static_cast<int>(desc.family) > PP_BROWSERFONT_TRUSTED_FAMILY_MONOSPACE)
+    return false;
+  if (static_cast<int>(desc.weight) < PP_BROWSERFONT_TRUSTED_WEIGHT_100 ||
+      static_cast<int>(desc.weight) > PP_BROWSERFONT_TRUSTED_WEIGHT_900)
+    return false;
+
+  // Check for excessive sizes which may cause layout to get confused.
+  if (desc.size > 200)
+    return false;
+
+  return true;
+}
+
+BrowserFontResource_Trusted::BrowserFontResource_Trusted(
+    ppapi::proxy::Connection connection,
+    PP_Instance instance,
+    const PP_BrowserFont_Trusted_Description& desc,
+    const ppapi::Preferences& prefs)
+    : PluginResource(connection, instance),
+      font_(WebFont::create(PPFontDescToWebFontDesc(desc, prefs))) {
+}
+
+BrowserFontResource_Trusted::~BrowserFontResource_Trusted() {
+}
+
+ppapi::thunk::PPB_BrowserFont_Trusted_API*
+BrowserFontResource_Trusted::AsPPB_BrowserFont_Trusted_API() {
+  return this;
+}
+
+PP_Bool BrowserFontResource_Trusted::Describe(
+    PP_BrowserFont_Trusted_Description* description,
+    PP_BrowserFont_Trusted_Metrics* metrics) {
+  if (description->face.type != PP_VARTYPE_UNDEFINED)
+    return PP_FALSE;
+
+  // While converting the other way in PPFontDescToWebFontDesc we validated
+  // that the enums can be casted.
+  WebFontDescription web_desc = font_->fontDescription();
+  description->face = StringVar::StringToPPVar(UTF16ToUTF8(web_desc.family));
+  description->family =
+      static_cast<PP_BrowserFont_Trusted_Family>(web_desc.genericFamily);
+  description->size = static_cast<uint32_t>(web_desc.size);
+  description->weight = static_cast<PP_BrowserFont_Trusted_Weight>(
+      web_desc.weight);
+  description->italic = web_desc.italic ? PP_TRUE : PP_FALSE;
+  description->small_caps = web_desc.smallCaps ? PP_TRUE : PP_FALSE;
+  description->letter_spacing = static_cast<int32_t>(web_desc.letterSpacing);
+  description->word_spacing = static_cast<int32_t>(web_desc.wordSpacing);
+
+  metrics->height = font_->height();
+  metrics->ascent = font_->ascent();
+  metrics->descent = font_->descent();
+  metrics->line_spacing = font_->lineSpacing();
+  metrics->x_height = static_cast<int32_t>(font_->xHeight());
+
+  // Convert the string.
+  return PP_TRUE;
+}
+
+PP_Bool BrowserFontResource_Trusted::DrawTextAt(
+    PP_Resource image_data,
+    const PP_BrowserFont_Trusted_TextRun* text,
+    const PP_Point* position,
+    uint32_t color,
+    const PP_Rect* clip,
+    PP_Bool image_data_is_opaque) {
+  PP_Bool result = PP_FALSE;
+  // Get and map the image data we're painting to.
+  EnterResourceNoLock<PPB_ImageData_API> enter(image_data, true);
+  if (enter.failed())
+    return result;
+
+  PPB_ImageData_API* image = static_cast<PPB_ImageData_API*>(
+      enter.object());
+  SkCanvas* canvas = image->GetPlatformCanvas();
+  bool needs_unmapping = false;
+  if (!canvas) {
+    needs_unmapping = true;
+    image->Map();
+    canvas = image->GetPlatformCanvas();
+    if (!canvas)
+      return result;  // Failure mapping.
+  }
+
+  DrawTextToCanvas(canvas, *text, position, color, clip, image_data_is_opaque);
+
+  if (needs_unmapping)
+    image->Unmap();
+  return PP_TRUE;
+}
+
+int32_t BrowserFontResource_Trusted::MeasureText(
+    const PP_BrowserFont_Trusted_TextRun* text) {
+  WebTextRun run;
+  if (!PPTextRunToWebTextRun(*text, &run))
+    return -1;
+  return font_->calculateWidth(run);
+}
+
+uint32_t BrowserFontResource_Trusted::CharacterOffsetForPixel(
+    const PP_BrowserFont_Trusted_TextRun* text,
+    int32_t pixel_position) {
+  TextRunCollection runs(*text);
+  int32_t cur_pixel_offset = 0;
+  for (int i = 0; i < runs.num_runs(); i++) {
+    int32_t run_begin = 0;
+    int32_t run_len = 0;
+    WebTextRun run = runs.GetRunAt(i, &run_begin, &run_len);
+    int run_width = font_->calculateWidth(run);
+    if (pixel_position < cur_pixel_offset + run_width) {
+      // Offset is in this run.
+      return static_cast<uint32_t>(font_->offsetForPosition(
+              run, static_cast<float>(pixel_position - cur_pixel_offset))) +
+          run_begin;
+    }
+    cur_pixel_offset += run_width;
+  }
+  return runs.text().size();
+}
+
+int32_t BrowserFontResource_Trusted::PixelOffsetForCharacter(
+    const PP_BrowserFont_Trusted_TextRun* text,
+    uint32_t char_offset) {
+  TextRunCollection runs(*text);
+  int32_t cur_pixel_offset = 0;
+  for (int i = 0; i < runs.num_runs(); i++) {
+    int32_t run_begin = 0;
+    int32_t run_len = 0;
+    WebTextRun run = runs.GetRunAt(i, &run_begin, &run_len);
+    if (char_offset >= static_cast<uint32_t>(run_begin) &&
+        char_offset < static_cast<uint32_t>(run_begin + run_len)) {
+      // Character we're looking for is in this run.
+      //
+      // Here we ask WebKit to give us the rectangle around the character in
+      // question, and then return the left edge. If we asked for a range of
+      // 0 characters starting at the character in question, it would give us
+      // a 0-width rect around the insertion point. But that will be on the
+      // right side of the character for an RTL run, which would be wrong.
+      WebFloatRect rect = font_->selectionRectForText(
+          run, WebFloatPoint(0.0f, 0.0f), font_->height(),
+          char_offset - run_begin, char_offset - run_begin + 1);
+      return cur_pixel_offset + static_cast<int>(rect.x);
+    } else {
+      // Character is past this run, account for the pixels and continue
+      // looking.
+      cur_pixel_offset += font_->calculateWidth(run);
+    }
+  }
+  return -1;  // Requested a char beyond the end.
+}
+
+void BrowserFontResource_Trusted::DrawTextToCanvas(
+    SkCanvas* destination,
+    const PP_BrowserFont_Trusted_TextRun& text,
+    const PP_Point* position,
+    uint32_t color,
+    const PP_Rect* clip,
+    PP_Bool image_data_is_opaque) {
+  // Convert position and clip.
+  WebFloatPoint web_position(static_cast<float>(position->x),
+                             static_cast<float>(position->y));
+  WebRect web_clip;
+  if (!clip) {
+    // Use entire canvas. SkCanvas doesn't have a size on it, so we just use
+    // the current clip bounds.
+    SkRect skclip;
+    destination->getClipBounds(&skclip);
+    web_clip = WebRect(skclip.fLeft, skclip.fTop, skclip.fRight - skclip.fLeft,
+                       skclip.fBottom - skclip.fTop);
+  } else {
+    web_clip = WebRect(clip->point.x, clip->point.y,
+                       clip->size.width, clip->size.height);
+  }
+
+  TextRunCollection runs(text);
+  for (int i = 0; i < runs.num_runs(); i++) {
+    int32_t run_begin = 0;
+    int32_t run_len = 0;
+    WebTextRun run = runs.GetRunAt(i, &run_begin, &run_len);
+    font_->drawText(destination, run, web_position, color, web_clip,
+                    PP_ToBool(image_data_is_opaque));
+
+    // Advance to the next run. Note that we avoid doing this for the last run
+    // since it's unnecessary, measuring text is slow, and most of the time
+    // there will be only one run anyway.
+    if (i != runs.num_runs() - 1)
+      web_position.x += font_->calculateWidth(run);
+  }
+}
+
+}  // namespace content