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/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _BOOTANIMATION_BOOT_PARAMETERS_H_
#define _BOOTANIMATION_BOOT_PARAMETERS_H_

#include <list>
#include <vector>

#include <base/json/json_value_converter.h>
#include <boot_action/boot_action.h>  // libandroidthings native API.

namespace android {

// Provides access to the parameters set by DeviceManager.reboot().
class BootParameters {
public:
    // Constructor loads the parameters for this boot and swaps the param files
    // to clear the parameters for next boot.
    BootParameters();

    // Returns true if volume/brightness were explicitly set on reboot.
    bool hasVolume() const { return mVolume >= 0; }
    bool hasBrightness() const { return mBrightness >= 0; }

    // Returns volume/brightness in [0,1], or -1 if unset.
    float getVolume() const { return mVolume; }
    float getBrightness() const { return mBrightness; }

    // Returns the additional boot parameters that were set on reboot.
    const std::vector<ABootActionParameter>& getParameters() const { return mParameters; }

private:
    // Raw boot saved_parameters loaded from .json.
    struct SavedBootParameters {
        int brightness;
        int volume;
        std::vector<std::unique_ptr<std::string>> param_names;
        std::vector<std::unique_ptr<std::string>> param_values;

        SavedBootParameters();
        static void RegisterJSONConverter(
                ::base::JSONValueConverter<SavedBootParameters>* converter);
    };

    void loadParameters();

    float mVolume = -1.f;
    float mBrightness = -1.f;
    std::vector<ABootActionParameter> mParameters;

    // ABootActionParameter is just a raw pointer so we need to keep the
    // original strings around to avoid losing them.
    SavedBootParameters mRawParameters;
};

}  // namespace android


#endif  // _BOOTANIMATION_BOOT_PARAMETERS_H_