CSSPrimitiveValueUnitTrie.cpp

// Copyright 2016 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/CSSPrimitiveValueUnitTrie.h"
#include "core/css/CSSPrimitiveValue.h"

namespace blink {

namespace {

template<typename CharacterType>
CSSPrimitiveValue::UnitType cssPrimitiveValueUnitFromTrie(const CharacterType* data, unsigned length)
{
    DCHECK(data);
    DCHECK(length);
    switch(length) {
    case 0:
        return CSSPrimitiveValue::UnitType::UserUnits;
    case 1:
        switch (toASCIILower(data[0])) {
        case 's':
            return CSSPrimitiveValue::UnitType::Seconds;
        }
        break;
    case 2:
        switch (toASCIILower(data[0])) {
        case 'c':
            switch (toASCIILower(data[1])) {
            case 'h':
                return CSSPrimitiveValue::UnitType::Chs;
            case 'm':
                return CSSPrimitiveValue::UnitType::Centimeters;
            }
            break;
        case 'e':
            switch (toASCIILower(data[1])) {
            case 'm':
                return CSSPrimitiveValue::UnitType::Ems;
            case 'x':
                return CSSPrimitiveValue::UnitType::Exs;
            }
            break;
        case 'f':
            if (toASCIILower(data[1]) == 'r')
                return CSSPrimitiveValue::UnitType::Fraction;
            break;
        case 'h':
            if (toASCIILower(data[1]) == 'z')
                return CSSPrimitiveValue::UnitType::Hertz;
            break;
        case 'i':
            if (toASCIILower(data[1]) == 'n')
                return CSSPrimitiveValue::UnitType::Inches;
            break;
        case 'm':
            switch (toASCIILower(data[1])) {
            case 'm':
                return CSSPrimitiveValue::UnitType::Millimeters;
            case 's':
                return CSSPrimitiveValue::UnitType::Milliseconds;
            }
            break;
        case 'p':
            switch (toASCIILower(data[1])) {
            case 'c':
                return CSSPrimitiveValue::UnitType::Picas;
            case 't':
                return CSSPrimitiveValue::UnitType::Points;
            case 'x':
                return CSSPrimitiveValue::UnitType::Pixels;
            }
            break;
        case 'v':
            switch (toASCIILower(data[1])) {
            case 'h':
                return CSSPrimitiveValue::UnitType::ViewportHeight;
            case 'w':
                return CSSPrimitiveValue::UnitType::ViewportWidth;
            }
            break;
        }
        break;
    case 3:
        switch (toASCIILower(data[0])) {
        case 'd':
            switch (toASCIILower(data[1])) {
            case 'e':
                if (toASCIILower(data[2]) == 'g')
                    return CSSPrimitiveValue::UnitType::Degrees;
                break;
            case 'p':
                if (toASCIILower(data[2]) == 'i')
                    return CSSPrimitiveValue::UnitType::DotsPerInch;
                break;
            }
            break;
        case 'k':
            if (toASCIILower(data[1]) == 'h' && toASCIILower(data[2]) == 'z')
                return CSSPrimitiveValue::UnitType::Kilohertz;
            break;
        case 'r':
            switch (toASCIILower(data[1])) {
            case 'a':
                if (toASCIILower(data[2]) == 'd')
                    return CSSPrimitiveValue::UnitType::Radians;
                break;
            case 'e':
                if (toASCIILower(data[2]) == 'm')
                    return CSSPrimitiveValue::UnitType::Rems;
                break;
            }
            break;
        }
        break;
    case 4:
        switch (toASCIILower(data[0])) {
        case 'd':
            switch (toASCIILower(data[1])) {
            case 'p':
                switch (toASCIILower(data[2])) {
                case 'c':
                    if (toASCIILower(data[3]) == 'm')
                        return CSSPrimitiveValue::UnitType::DotsPerCentimeter;
                    break;
                case 'p':
                    if (toASCIILower(data[3]) == 'x')
                        return CSSPrimitiveValue::UnitType::DotsPerPixel;
                    break;
                }
                break;
            }
            break;
        case 'g':
            if (toASCIILower(data[1]) == 'r' && toASCIILower(data[2]) == 'a' && toASCIILower(data[3]) == 'd')
                return CSSPrimitiveValue::UnitType::Gradians;
            break;
        case 't':
            if (toASCIILower(data[1]) == 'u' && toASCIILower(data[2]) == 'r' && toASCIILower(data[3]) == 'n')
                return CSSPrimitiveValue::UnitType::Turns;
            break;
        case 'v':
            switch (toASCIILower(data[1])) {
            case 'm':
                switch (toASCIILower(data[2])) {
                case 'a':
                    if (toASCIILower(data[3]) == 'x')
                        return CSSPrimitiveValue::UnitType::ViewportMax;
                    break;
                case 'i':
                    if (toASCIILower(data[3]) == 'n')
                        return CSSPrimitiveValue::UnitType::ViewportMin;
                    break;
                }
                break;
            }
            break;
        }
        break;
    case 5:
        switch (toASCIILower(data[0])) {
        case '_':
            if (toASCIILower(data[1]) == '_' && toASCIILower(data[2]) == 'q' && toASCIILower(data[3]) == 'e' && toASCIILower(data[4]) == 'm')
                return CSSPrimitiveValue::UnitType::QuirkyEms;
            break;
        }
        break;
    }
    return CSSPrimitiveValue::UnitType::Unknown;
}

} // namespace

CSSPrimitiveValue::UnitType lookupCSSPrimitiveValueUnit(const LChar* characters8, unsigned length)
{
    return cssPrimitiveValueUnitFromTrie(characters8, length);
}

CSSPrimitiveValue::UnitType lookupCSSPrimitiveValueUnit(const UChar* characters16, unsigned length)
{
    return cssPrimitiveValueUnitFromTrie(characters16, length);
}

} // namespace blink