Source/modules/mediastream/MediaConstraintsImpl.cpp

/*
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#include "config.h"

#include "modules/mediastream/MediaConstraintsImpl.h"

#include "bindings/core/v8/ArrayValue.h"
#include "bindings/core/v8/Dictionary.h"
#include "bindings/core/v8/ExceptionState.h"
#include "core/dom/ExceptionCode.h"
#include "wtf/HashMap.h"
#include "wtf/Vector.h"
#include "wtf/text/StringHash.h"

namespace blink {

namespace MediaConstraintsImpl {

static bool parse(const Dictionary& constraintsDictionary, WebVector<WebMediaConstraint>& optional, WebVector<WebMediaConstraint>& mandatory)
{
    if (constraintsDictionary.isUndefinedOrNull())
        return true;

    Vector<String> names;
    constraintsDictionary.getOwnPropertyNames(names);

    String mandatoryName("mandatory");
    String optionalName("optional");

    for (Vector<String>::iterator it = names.begin(); it != names.end(); ++it) {
        if (*it != mandatoryName && *it != optionalName)
            return false;
    }

    Vector<WebMediaConstraint> mandatoryConstraintsVector;
    if (names.contains(mandatoryName)) {
        Dictionary mandatoryConstraintsDictionary;
        bool ok = constraintsDictionary.get(mandatoryName, mandatoryConstraintsDictionary);
        if (!ok || mandatoryConstraintsDictionary.isUndefinedOrNull())
            return false;

        HashMap<String, String> mandatoryConstraintsHashMap;
        ok = mandatoryConstraintsDictionary.getOwnPropertiesAsStringHashMap(mandatoryConstraintsHashMap);
        if (!ok)
            return false;

        HashMap<String, String>::const_iterator iter = mandatoryConstraintsHashMap.begin();
        for (; iter != mandatoryConstraintsHashMap.end(); ++iter)
            mandatoryConstraintsVector.append(WebMediaConstraint(iter->key, iter->value));
    }

    Vector<WebMediaConstraint> optionalConstraintsVector;
    if (names.contains(optionalName)) {
        ArrayValue optionalConstraints;
        bool ok = DictionaryHelper::get(constraintsDictionary, optionalName, optionalConstraints);
        if (!ok || optionalConstraints.isUndefinedOrNull())
            return false;

        size_t numberOfConstraints;
        ok = optionalConstraints.length(numberOfConstraints);
        if (!ok)
            return false;

        for (size_t i = 0; i < numberOfConstraints; ++i) {
            Dictionary constraint;
            ok = optionalConstraints.get(i, constraint);
            if (!ok || constraint.isUndefinedOrNull())
                return false;
            Vector<String> localNames;
            constraint.getOwnPropertyNames(localNames);
            if (localNames.size() != 1)
                return false;
            String key = localNames[0];
            String value;
            ok = DictionaryHelper::get(constraint, key, value);
            if (!ok)
                return false;
            optionalConstraintsVector.append(WebMediaConstraint(key, value));
        }
    }

    optional.assign(optionalConstraintsVector);
    mandatory.assign(mandatoryConstraintsVector);
    return true;
}


WebMediaConstraints create(const Dictionary& constraintsDictionary, ExceptionState& exceptionState)
{
    WebVector<WebMediaConstraint> optional;
    WebVector<WebMediaConstraint> mandatory;
    if (!parse(constraintsDictionary, optional, mandatory)) {
        exceptionState.throwTypeError("Malformed constraints object.");
        return WebMediaConstraints();
    }

    WebMediaConstraints constraints;
    constraints.initialize(optional, mandatory);
    return constraints;
}

WebMediaConstraints create()
{
    WebMediaConstraints constraints;
    constraints.initialize();
    return constraints;
}

} // namespace MediaConstraintsImpl
} // namespace blink