Added CSSPropertyShapeUtils which holds shape parsing methods.

third_party/WebKit/Source/core/css/properties/CSSPropertyShapeUtils.cpp

+// Copyright 2017 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 "core/css/properties/CSSPropertyShapeUtils.h"
+
+#include "core/css/CSSBasicShapeValues.h"
+#include "core/css/parser/CSSParserContext.h"
+#include "core/css/parser/CSSParserMode.h"
+#include "core/css/parser/CSSParserTokenRange.h"
+#include "core/css/parser/CSSPropertyParserHelpers.h"
+
+namespace blink {
+
+using namespace CSSPropertyParserHelpers;
+
+namespace {
+
+static CSSValue* consumeShapeRadius(CSSParserTokenRange& args,
+                                    CSSParserMode cssParserMode) {
+  if (identMatches<CSSValueClosestSide, CSSValueFarthestSide>(args.peek().id()))
+    return consumeIdent(args);
+  return consumeLengthOrPercent(args, cssParserMode, ValueRangeNonNegative);
+}
+
+static CSSBasicShapeCircleValue* consumeBasicShapeCircle(
+    CSSParserTokenRange& args,
+    const CSSParserContext* context) {
+  // spec: https://drafts.csswg.org/css-shapes/#supported-basic-shapes
+  // circle( [<shape-radius>]? [at <position>]? )
+  CSSBasicShapeCircleValue* shape = CSSBasicShapeCircleValue::create();
+  if (CSSValue* radius = consumeShapeRadius(args, context->mode()))
+    shape->setRadius(radius);
+  if (consumeIdent<CSSValueAt>(args)) {
+    CSSValue* centerX = nullptr;
+    CSSValue* centerY = nullptr;
+    if (!consumePosition(args, context->mode(), UnitlessQuirk::Forbid, centerX,
+                         centerY))
+      return nullptr;
+    shape->setCenterX(centerX);
+    shape->setCenterY(centerY);
+  }
+  return shape;
+}
+
+static CSSBasicShapeEllipseValue* consumeBasicShapeEllipse(
+    CSSParserTokenRange& args,
+    const CSSParserContext* context) {
+  // spec: https://drafts.csswg.org/css-shapes/#supported-basic-shapes
+  // ellipse( [<shape-radius>{2}]? [at <position>]? )
+  CSSBasicShapeEllipseValue* shape = CSSBasicShapeEllipseValue::create();
+  if (CSSValue* radiusX = consumeShapeRadius(args, context->mode())) {
+    shape->setRadiusX(radiusX);
+    if (CSSValue* radiusY = consumeShapeRadius(args, context->mode()))
+      shape->setRadiusY(radiusY);
+  }
+  if (consumeIdent<CSSValueAt>(args)) {
+    CSSValue* centerX = nullptr;
+    CSSValue* centerY = nullptr;
+    if (!consumePosition(args, context->mode(), UnitlessQuirk::Forbid, centerX,
+                         centerY))
+      return nullptr;
+    shape->setCenterX(centerX);
+    shape->setCenterY(centerY);
+  }
+  return shape;
+}
+
+static CSSBasicShapePolygonValue* consumeBasicShapePolygon(
+    CSSParserTokenRange& args,
+    const CSSParserContext* context) {
+  CSSBasicShapePolygonValue* shape = CSSBasicShapePolygonValue::create();
+  if (identMatches<CSSValueEvenodd, CSSValueNonzero>(args.peek().id())) {
+    shape->setWindRule(args.consumeIncludingWhitespace().id() == CSSValueEvenodd
+                           ? RULE_EVENODD
+                           : RULE_NONZERO);
+    if (!consumeCommaIncludingWhitespace(args))
+      return nullptr;
+  }
+
+  do {
+    CSSPrimitiveValue* xLength =
+        consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+    if (!xLength)
+      return nullptr;
+    CSSPrimitiveValue* yLength =
+        consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+    if (!yLength)
+      return nullptr;
+    shape->appendPoint(xLength, yLength);
+  } while (consumeCommaIncludingWhitespace(args));
+  return shape;
+}
+
+static CSSBasicShapeInsetValue* consumeBasicShapeInset(
+    CSSParserTokenRange& args,
+    const CSSParserContext* context) {
+  CSSBasicShapeInsetValue* shape = CSSBasicShapeInsetValue::create();
+  CSSPrimitiveValue* top =
+      consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+  if (!top)
+    return nullptr;
+  CSSPrimitiveValue* right =
+      consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+  CSSPrimitiveValue* bottom = nullptr;
+  CSSPrimitiveValue* left = nullptr;
+  if (right) {
+    bottom = consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+    if (bottom)
+      left = consumeLengthOrPercent(args, context->mode(), ValueRangeAll);
+  }
+  if (left)
+    shape->updateShapeSize4Values(top, right, bottom, left);
+  else if (bottom)
+    shape->updateShapeSize3Values(top, right, bottom);
+  else if (right)
+    shape->updateShapeSize2Values(top, right);
+  else
+    shape->updateShapeSize1Value(top);
+
+  if (consumeIdent<CSSValueRound>(args)) {
+    CSSValue* horizontalRadii[4] = {0};
+    CSSValue* verticalRadii[4] = {0};
+    if (!CSSPropertyShapeUtils::consumeRadii(horizontalRadii, verticalRadii,
+                                             args, context->mode(), false))
+      return nullptr;
+    shape->setTopLeftRadius(
+        CSSValuePair::create(horizontalRadii[0], verticalRadii[0],
+                             CSSValuePair::DropIdenticalValues));
+    shape->setTopRightRadius(
+        CSSValuePair::create(horizontalRadii[1], verticalRadii[1],
+                             CSSValuePair::DropIdenticalValues));
+    shape->setBottomRightRadius(
+        CSSValuePair::create(horizontalRadii[2], verticalRadii[2],
+                             CSSValuePair::DropIdenticalValues));
+    shape->setBottomLeftRadius(
+        CSSValuePair::create(horizontalRadii[3], verticalRadii[3],
+                             CSSValuePair::DropIdenticalValues));
+  }
+  return shape;
+}
+
+}  // namespace
+
+bool CSSPropertyShapeUtils::consumeRadii(CSSValue* horizontalRadii[4],
+                                         CSSValue* verticalRadii[4],
+                                         CSSParserTokenRange& range,
+                                         CSSParserMode cssParserMode,
+                                         bool useLegacyParsing) {
+  unsigned i = 0;
+  for (; i < 4 && !range.atEnd() && range.peek().type() != DelimiterToken;
+       ++i) {
+    horizontalRadii[i] =
+        consumeLengthOrPercent(range, cssParserMode, ValueRangeNonNegative);
+    if (!horizontalRadii[i])
+      return false;
+  }
+  if (!horizontalRadii[0])
+    return false;
+  if (range.atEnd()) {
+    // Legacy syntax: -webkit-border-radius: l1 l2; is equivalent to
+    // border-radius: l1 / l2;
+    if (useLegacyParsing && i == 2) {
+      verticalRadii[0] = horizontalRadii[1];
+      horizontalRadii[1] = nullptr;
+    } else {
+      complete4Sides(horizontalRadii);
+      for (unsigned i = 0; i < 4; ++i)
+        verticalRadii[i] = horizontalRadii[i];
+      return true;
+    }
+  } else {
+    if (!consumeSlashIncludingWhitespace(range))
+      return false;
+    for (i = 0; i < 4 && !range.atEnd(); ++i) {
+      verticalRadii[i] =
+          consumeLengthOrPercent(range, cssParserMode, ValueRangeNonNegative);
+      if (!verticalRadii[i])
+        return false;
+    }
+    if (!verticalRadii[0] || !range.atEnd())
+      return false;
+  }
+  complete4Sides(horizontalRadii);
+  complete4Sides(verticalRadii);
+  return true;
+}
+
+CSSValue* CSSPropertyShapeUtils::consumeBasicShape(
+    CSSParserTokenRange& range,
+    const CSSParserContext* context) {
+  CSSValue* shape = nullptr;
+  if (range.peek().type() != FunctionToken)
+    return nullptr;
+  CSSValueID id = range.peek().functionId();
+  CSSParserTokenRange rangeCopy = range;
+  CSSParserTokenRange args = consumeFunction(rangeCopy);
+  if (id == CSSValueCircle)
+    shape = consumeBasicShapeCircle(args, context);
+  else if (id == CSSValueEllipse)
+    shape = consumeBasicShapeEllipse(args, context);
+  else if (id == CSSValuePolygon)
+    shape = consumeBasicShapePolygon(args, context);
+  else if (id == CSSValueInset)
+    shape = consumeBasicShapeInset(args, context);
+  if (!shape || !args.atEnd())
+    return nullptr;
+  range = rangeCopy;
+  return shape;
+}
+
+}  // namespace blink