/*
 *  Copyright (C) 2012-2018 Team Kodi
 *  This file is part of Kodi - https://kodi.tv
 *
 *  SPDX-License-Identifier: GPL-2.0-or-later
 *  See LICENSES/README.md for more information.
 */

#pragma once

#include "pvr/channels/PVRChannelGroup.h"
#include "threads/CriticalSection.h"

#include <memory>
#include <mutex>
#include <string>
#include <vector>

namespace PVR
{
  class CPVRChannel;
  class CPVRClient;

  /** A container class for channel groups */

  class CPVRChannelGroups
  {
  public:
    /*!
     * @brief Create a new group container.
     * @param bRadio True if this is a container for radio channels, false if it is for tv channels.
     */
    explicit CPVRChannelGroups(bool bRadio);
    virtual ~CPVRChannelGroups();

    /*!
     * @brief Remove all groups from this container.
     */
    void Unload();

    /*!
     * @brief Load all channel groups and all channels from PVR database.
     * @param clients The PVR clients data should be loaded for. Leave empty for all clients.
     * @return True on success, false otherwise.
     */
    bool LoadFromDatabase(const std::vector<std::shared_ptr<CPVRClient>>& clients);

    /*!
     * @brief Create a channel group matching the given type.
     * @param iType The type for the group.
     * @param path The path of the group.
     * @return The new group.
     */
    std::shared_ptr<CPVRChannelGroup> CreateChannelGroup(int iType, const CPVRChannelsPath& path);

    /*!
     * @return Amount of groups in this container
     */
    size_t Size() const
    {
      std::unique_lock<CCriticalSection> lock(m_critSection);
      return m_groups.size();
    }

    /*!
     * @brief Update a group or add it if it's not in here yet.
     * @param group The group to update.
     * @param bUpdateFromClient True to save the changes in the db.
     * @return True if the group was added or update successfully, false otherwise.
     */
    bool Update(const std::shared_ptr<CPVRChannelGroup>& group, bool bUpdateFromClient = false);

    /*!
     * @brief Called by the add-on callback to add a new group
     * @param group The group to add
     * @return True when updated, false otherwise
     */
    bool UpdateFromClient(const std::shared_ptr<CPVRChannelGroup>& group)
    {
      return Update(group, true);
    }

    /*!
     * @brief Get a channel group member given its path
     * @param strPath The path to the channel group member
     * @return The channel group member, or nullptr if not found
     */
    std::shared_ptr<CPVRChannelGroupMember> GetChannelGroupMemberByPath(
        const CPVRChannelsPath& path) const;

    /*!
     * @brief Get a pointer to a channel group given its ID.
     * @param iGroupId The ID of the group.
     * @return The group or NULL if it wasn't found.
     */
    std::shared_ptr<CPVRChannelGroup> GetById(int iGroupId) const;

    /*!
     * @brief Get all groups the given channel is a member.
     * @param channel The channel.
     * @param bExcludeHidden Whenever to exclude hidden channel groups.
     * @return A list of groups the channel is a member.
     */
    std::vector<std::shared_ptr<CPVRChannelGroup>> GetGroupsByChannel(const std::shared_ptr<CPVRChannel>& channel, bool bExcludeHidden = false) const;

    /*!
     * @brief Get a channel group given its path
     * @param strPath The path to the channel group
     * @return The channel group, or nullptr if not found
     */
    std::shared_ptr<CPVRChannelGroup> GetGroupByPath(const std::string& strPath) const;

    /*!
     * @brief Get a group given its name.
     * @param strName The name.
     * @return The group or NULL if it wasn't found.
     */
    std::shared_ptr<CPVRChannelGroup> GetByName(const std::string& strName) const;

    /*!
     * @brief Get the group that contains all channels.
     * @return The group that contains all channels.
     */
    std::shared_ptr<CPVRChannelGroup> GetGroupAll() const;

    /*!
     * @return The first group in this container, which always is the group with all channels.
     */
    std::shared_ptr<CPVRChannelGroup> GetFirstGroup() const { return GetGroupAll(); }

    /*!
     * @return The last group in this container.
     */
    std::shared_ptr<CPVRChannelGroup> GetLastGroup() const;

    /*!
     * @return The last and previous to last played channel group members. pair.first contains the last, pair.second the previous to last member.
     */
    GroupMemberPair GetLastAndPreviousToLastPlayedChannelGroupMember() const;

    /*!
     * @return The last opened group.
     */
    std::shared_ptr<CPVRChannelGroup> GetLastOpenedGroup() const;

    /*!
     * @brief Get the list of groups.
     * @param groups The list to store the results in.
     * @param bExcludeHidden Whenever to exclude hidden channel groups.
     * @return The amount of items that were added.
     */
    std::vector<std::shared_ptr<CPVRChannelGroup>> GetMembers(bool bExcludeHidden = false) const;

    /*!
     * @brief Get the previous group in this container.
     * @param group The current group.
     * @return The previous group or the group containing all channels if it wasn't found.
     */
    std::shared_ptr<CPVRChannelGroup> GetPreviousGroup(const CPVRChannelGroup& group) const;

    /*!
     * @brief Get the next group in this container.
     * @param group The current group.
     * @return The next group or the group containing all channels if it wasn't found.
     */
    std::shared_ptr<CPVRChannelGroup> GetNextGroup(const CPVRChannelGroup& group) const;

    /*!
     * @brief Add a group to this container.
     * @param strName The name of the group.
     * @return True if the group was added, false otherwise.
     */
    bool AddGroup(const std::string& strName);

    /*!
     * @brief Remove a group from this container and delete it from the database.
     * @param group The group to delete.
     * @return True if it was deleted successfully, false if not.
     */
    bool DeleteGroup(const std::shared_ptr<CPVRChannelGroup>& group);

    /*!
     * @brief Hide/unhide a group in this container.
     * @param group The group to hide/unhide.
     * @param bHide True to hide the group, false to unhide it.
     * @return True on success, false otherwise.
     */
    bool HideGroup(const std::shared_ptr<CPVRChannelGroup>& group, bool bHide);

    /*!
     * @brief Create EPG tags for all channels of the internal group.
     * @return True if EPG tags where created successfully, false if not.
     */
    bool CreateChannelEpgs();

    /*!
     * @brief Persist all changes in channel groups.
     * @return True if everything was persisted, false otherwise.
     */
    bool PersistAll();

    /*!
     * @return True when this container contains radio groups, false otherwise
     */
    bool IsRadio() const { return m_bRadio; }

    /*!
     * @brief Update data with groups and channels from the given clients, sync with local data.
     * @param clients The clients to fetch data from. Leave empty to fetch data from all created clients.
     * @param bChannelsOnly Set to true to only update channels, not the groups themselves.
     * @return True on success, false otherwise.
     */
    bool UpdateFromClients(const std::vector<std::shared_ptr<CPVRClient>>& clients,
                           bool bChannelsOnly = false);

    /*!
     * @brief Update the channel numbers across the channel groups from the all channels group
     * @return True if any channel number was changed, false otherwise.
     */
    bool UpdateChannelNumbersFromAllChannelsGroup();

    /*!
     * @brief Erase stale texture db entries and image files.
     * @return number of cleaned up images.
     */
    int CleanupCachedImages();

  private:
    void SortGroups();

    /*!
     * @brief Check, whether data for given pvr clients are currently valid. For instance, data
     * can be invalid because the client's backend was offline when data was last queried.
     * @param clients The clients to check. Check all active clients if vector is empty.
     * @return True, if data is currently valid, false otherwise.
     */
    bool HasValidDataForClients(const std::vector<std::shared_ptr<CPVRClient>>& clients) const;

    bool m_bRadio; /*!< true if this is a container for radio channels, false if it is for tv channels */
    std::vector<std::shared_ptr<CPVRChannelGroup>> m_groups; /*!< the groups in this container */
    mutable CCriticalSection m_critSection;
    std::vector<int> m_failedClientsForChannelGroups;
  };
}