/*

 *

 *    Copyright (c) 2024-2025 Project CHIP Authors

 *    All rights reserved.

 *

 *    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.

 */

#pragma once

#include <app/clusters/thermostat-server/ThermostatDelegate.h>

namespace chip {

namespace app {

namespace Clusters {

namespace Thermostat {

/**

 * The ThermostatDelegate class serves as the instance delegate for storing Presets related information and providing it to the

 * Thermostat server code. It also manages the presets attribute and provides methods to write to presets, edit presets, maintain a

 * pending presets list and either commit the presets when requested or discard the changes. It also provides APIs to get and set

 * the attribute values.

 *

 */

static constexpr uint8_t kMaxNumberOfPresetTypes = 6;

static constexpr uint8_t kMaxNumberOfThermostatSuggestions = 5;

static constexpr uint8_t kMaxNumberOfScheduleTypes = 2;

// TODO: #34556 Support multiple presets/schedules of each type.

// We will support only one preset of each preset/schedule type.

static constexpr uint8_t kMaxNumberOfPresetsOfEachType   = 1;

static constexpr uint8_t kMaxNumberOfSchedulesOfEachType = 1;

// For testing the use case where number of presets added exceeds the number of presets supported, we will have the value of

// kMaxNumberOfPresetsSupported < kMaxNumberOfPresetTypes * kMaxNumberOfPresetsOfEachType

static constexpr uint8_t kMaxNumberOfPresetsSupported = kMaxNumberOfPresetTypes * kMaxNumberOfPresetsOfEachType - 1;

static constexpr uint8_t kMaxNumberOfSchedulesSupported = kMaxNumberOfScheduleTypes * kMaxNumberOfSchedulesOfEachType - 1;

class ThermostatDelegate : public Delegate

{

public:

    static inline ThermostatDelegate & GetInstance() { return sInstance; }

    std::optional<System::Clock::Milliseconds16> GetMaxAtomicWriteTimeout(chip::AttributeId attributeId) override;

    CHIP_ERROR GetPresetTypeAtIndex(size_t index, Structs::PresetTypeStruct::Type & presetType) override;

    uint8_t GetNumberOfPresets() override;

    CHIP_ERROR GetPresetAtIndex(size_t index, PresetStructWithOwnedMembers & preset) override;

    CHIP_ERROR GetActivePresetHandle(DataModel::Nullable<MutableByteSpan> & activePresetHandle) override;

    CHIP_ERROR SetActivePresetHandle(const DataModel::Nullable<ByteSpan> & newActivePresetHandle) override;

    void InitializePendingPresets() override;

    CHIP_ERROR AppendToPendingPresetList(const PresetStructWithOwnedMembers & preset) override;

    CHIP_ERROR GetPendingPresetAtIndex(size_t index, PresetStructWithOwnedMembers & preset) override;

    CHIP_ERROR CommitPendingPresets() override;

    void ClearPendingPresetList() override;

    uint8_t GetMaxThermostatSuggestions() override;

    uint8_t GetNumberOfThermostatSuggestions() override;

    CHIP_ERROR GetThermostatSuggestionAtIndex(size_t index,

                                              ThermostatSuggestionStructWithOwnedMembers & thermostatSuggestion) override;

    void GetCurrentThermostatSuggestion(

        DataModel::Nullable<ThermostatSuggestionStructWithOwnedMembers> & currentThermostatSuggestion) override;

    DataModel::Nullable<ThermostatSuggestionNotFollowingReasonBitmap> GetThermostatSuggestionNotFollowingReason() override;

    CHIP_ERROR AppendToThermostatSuggestionsList(const Structs::ThermostatSuggestionStruct::Type & thermostatSuggestion) override;

    CHIP_ERROR RemoveFromThermostatSuggestionsList(size_t indexToRemove) override;

    CHIP_ERROR GetUniqueID(uint8_t & uniqueID) override;

    CHIP_ERROR ReEvaluateCurrentSuggestion() override;

    CHIP_ERROR GetScheduleTypeAtIndex(size_t index, Structs::ScheduleTypeStruct::Type & scheduleType) override;

private:

    static ThermostatDelegate sInstance;

    ThermostatDelegate();

    ~ThermostatDelegate();

    ThermostatDelegate(const ThermostatDelegate &)             = delete;

    ThermostatDelegate & operator=(const ThermostatDelegate &) = delete;

    /**

     * @brief Initializes the preset types array with all preset types corresponding to PresetScenarioEnum.

     */

    void InitializePresetTypes();

    /**

     * @brief Initializes the presets array with some sample presets for testing.

     */

    void InitializePresets();

    /**

     * @brief return the index of the thermostat suggestion in the ThermostatSuggestions attribute with the earliest EffectiveTime

     * field. If there are no entries or an error occurs, returns the value in the MaxThermostatSuggestions attribute as an

     * invalid index.

     *

     */

    size_t GetThermostatSuggestionIndexWithEarliestEffectiveTime(System::Clock::Seconds32 currentMatterEpochTimestamp);

    CHIP_ERROR StartExpirationTimer(System::Clock::Seconds32 timeout);

    static void TimerExpiredCallback(System::Layer * systemLayer, void * appState);

    void CancelExpirationTimer();

    CHIP_ERROR SetThermostatSuggestionNotFollowingReason(

        const DataModel::Nullable<ThermostatSuggestionNotFollowingReasonBitmap> & thermostatSuggestionNotFollowingReason);

    void SetCurrentThermostatSuggestion(size_t index);

    bool HaveSuggestionWithID(uint8_t uniqueIDToFind);

    uint8_t mNumberOfPresets;

    Structs::PresetTypeStruct::Type mPresetTypes[kMaxNumberOfPresetTypes];

    PresetStructWithOwnedMembers mPresets[kMaxNumberOfPresetTypes * kMaxNumberOfPresetsOfEachType];

    PresetStructWithOwnedMembers mPendingPresets[kMaxNumberOfPresetTypes * kMaxNumberOfPresetsOfEachType];

    uint8_t mNextFreeIndexInPendingPresetsList;

    uint8_t mNextFreeIndexInPresetsList;

    uint8_t mActivePresetHandleData[kPresetHandleSize];

    size_t mActivePresetHandleDataSize;

    bool mActivePresetHandleIsNull = true;

    uint8_t mMaxThermostatSuggestions;

    ThermostatSuggestionStructWithOwnedMembers mThermostatSuggestions[kMaxNumberOfThermostatSuggestions];

    uint8_t mNextFreeIndexInThermostatSuggestionsList;

    uint8_t mUniqueID;

    // TODO: #39949 - This information should be stored in the cluster instance.

    size_t mIndexOfCurrentSuggestion;

    DataModel::Nullable<ThermostatSuggestionNotFollowingReasonBitmap> mThermostatSuggestionNotFollowingReason;

    bool mIsExpirationTimerRunning = false;

    uint8_t mMaxNumberOfSchedulesAllowedPerScheduleType;

    Structs::ScheduleTypeStruct::Type mScheduleTypes[kMaxNumberOfScheduleTypes];

    /**

     * @brief Initializes the schedules types array with example schedule types.

     */

    void InitializeScheduleTypes();

};

} // namespace Thermostat

} // namespace Clusters

} // namespace app

} // namespace chip