/**********************************************************************
 * LeechCraft - modular cross-platform feature rich internet client.
 * Copyright (C) 2006-2014  Georg Rudoy
 *
 * Boost Software License - Version 1.0 - August 17th, 2003
 *
 * Permission is hereby granted, free of charge, to any person or organization
 * obtaining a copy of the software and accompanying documentation covered by
 * this license (the "Software") to use, reproduce, display, distribute,
 * execute, and transmit the Software, and to prepare derivative works of the
 * Software, and to permit third-parties to whom the Software is furnished to
 * do so, all subject to the following:
 *
 * The copyright notices in the Software and this entire statement, including
 * the above license grant, this restriction and the following disclaimer,
 * must be included in all copies of the Software, in whole or in part, and
 * all derivative works of the Software, unless such copies or derivative
 * works are solely in the form of machine-executable object code generated by
 * a source language processor.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
 * SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
 * FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 **********************************************************************/

#pragma once

#include <QFlags>
#include <QMetaType>
#include "imessage.h"
#include "azothcommon.h"

class QAction;
class QImage;

namespace LeechCraft
{
namespace Azoth
{
	class IAccount;
	class IMessage;

	struct EntryStatus
	{
		State State_;
		QString StatusString_;

		EntryStatus ()
		: State_ (SOffline)
		{
		}

		EntryStatus (State state, const QString& str)
		: State_ (state)
		, StatusString_ (str)
		{
		}
	};

	inline bool operator== (const EntryStatus& es1, const EntryStatus& es2)
	{
		return es1.State_ == es2.State_ &&
				es1.StatusString_ == es2.StatusString_;
	}

	inline bool operator!= (const EntryStatus& es1, const EntryStatus& es2)
	{
		return !(es1 == es2);
	}

	/** @brief Represents a single entry in contact list.
	 *
	 * Everything that should go to the contact list should implement
	 * this interface: plain contacts, metacontacts, transports to other
	 * accounts in protocols like XMPP, and such.
	 *
	 * In some protocol an entry can have several destinations, like
	 * resources in XMPP protocol. In this case, GetVariants() should
	 * return the up-to-date list of variants that this entry may have
	 * as destinations.
	 *
	 * By default, entries are considered to be normal chat entries, and
	 * Azoth core would manage the chat widget (and, consequently, chat
	 * tabs) for such entries itself. Nevertheless, some entries may
	 * want to have custom behavior for their widgets or even have no
	 * widgets at all. In this case, they set FHasCustomChatWidget flag
	 * in GetEntryFeatures(). In this case Azoth core wouldn't care
	 * about their chat widgets at all. Instead, such entry would need
	 * to implement IMultiTabsWidget, for example, and the corresponding
	 * plugin would need to be a IMultiTabs.
	 *
	 * This interface provides only more or less basic functionality.
	 * Advanced features, like drawing attention and such, are in
	 * IAdvancedCLEntry.
	 *
	 * @sa IAdvancedCLEntry
	 */
	class ICLEntry
	{
	public:
		virtual ~ICLEntry () {}

		/** Represents the features that may be supported by a contant
		 * list entry.
		 */
		enum Feature
		{
			/** This entry is permanent and would appear in the next
			 * session too. It makes sense to save it to disk, for
			 * example, when shutting down.
			 *
			 * This also means that the entry has been accepted into
			 * some kind of contact list by the user.
			 */
			FPermanentEntry = 0x0000,

			/** This entry is not permanent and would cease existing
			 * after this login session.
			 */
			FSessionEntry = 0x0001,

			/** Mask (0000011) for FPermanentEntry and FSessionEntry.
			 */
			FMaskLongetivity = 0x0003,

			/** This entry supports renaming, so calls to SetEntryName()
			 * are not in vain.
			 */
			FSupportsRenames = 0x0020,

			/** This entry has a custom chat widget.
			 */
			FHasCustomChatWidget = 0x0040,

			/** This entry supports auth manipulations. It makes sense
			 * to request, remove, give, etc auth. In this case the
			 * entry should also implement IAuthable.
			 */
			FSupportsAuth = 0x0080,

			/** This entry supports moving between different groups.
			 */
			FSupportsGrouping = 0x0100,

			/** This entry represents a self-contact, for example, in XMPP.
			 */
			FSelfContact = 0x0200
		};

		Q_DECLARE_FLAGS (Features, Feature)

		enum class EntryType
		{
			/** This entry represents a standard chat.
			 */
			Chat,

			/** This entry represents a multi-user chatroom.
			 */
			MUC,

			/** This entry represents a private conversation in a
			 * multi-user chatroom.
			 */
			PrivateChat,

			/** This entry represents an unauthorized user that has
			 * requested authorization.
			 */
			UnauthEntry
		};

		/** Returns the entry as a QObject.
		 *
		 * @return Contact list entry as QObject.
		 */
		virtual QObject* GetQObject () = 0;

		/** Returns the pointer to the parent account that this entry
		 * belongs to.
		 *
		 * @return The parent account of this entry.
		 */
		virtual IAccount* GetParentAccount () const = 0;

		/** Returns the pointer to the parent CL entry, if any.
		 *
		 * This currently only makes sense for private chat entries,
		 * thus private chat entries (those that are of type
		 * ETPrivateChat) should return their parent room CL entry (of
		 * type ETMUC).
		 *
		 * If parent CL entry is not applicable, NULL should be
		 * returned.
		 *
		 * The default implementation returns NULL.
		 *
		 * @return Parent CL entry if applicable, NULL otherwise.
		 */
		virtual ICLEntry* GetParentCLEntry () const
		{
			return nullptr;
		}

		QObject* GetParentCLEntryObject () const
		{
			if (const auto entry = GetParentCLEntry ())
				return entry->GetQObject ();
			return nullptr;
		}

		/** Returns the OR-ed combination of Feature flags that
		 * describes the features supported by this contact list entry.
		 *
		 * @return The features supported by this entry.
		 */
		virtual Features GetEntryFeatures () const = 0;

		/** Returns the type of this entry.
		 *
		 * @return The type of this entry.
		 */
		virtual EntryType GetEntryType () const = 0;

		/** Returns the human-readable name of this entry.
		 *
		 * @return Human-readable name of this entry.
		 *
		 * @sa SetEntryName()
		 */
		virtual QString GetEntryName () const = 0;

		/** @brief Sets the human-readable name of this entry.
		 *
		 * The name is expected to be updated on the server immediately.
		 *
		 * @param[in] name The new human-readable name of this entry.
		 *
		 * @sa GetEntryName()
		 */
		virtual void SetEntryName (const QString& name) = 0;

		/** @brief Returns the ID of this entry.
		 *
		 * The ID must be unique among all entries and should not depend
		 * on the value returned by GetEntryName() (the human-readable
		 * name).
		 *
		 * The main difference between this and GetHumanReadableID() is
		 * that GetEntryID() is used for distinguishing different items
		 * in the contact list (and there may be several items for one
		 * remote), while GetHumanReadableID() is used to distinguish
		 * different remotes between each other. Also, GetEntryID()
		 * should be unique globally (for example, it may contain ID of
		 * the account in it).
		 *
		 * @return The unique and persistent ID of this entry.
		 *
		 * @sa GetHumanReadableID()
		 */
		virtual QString GetEntryID () const = 0;

		/** @brief Returns the human-readable ID of this entry.
		 *
		 * This function is used to obtain the human-readable identifier
		 * of this entry (for example, Jabber ID in case of XMPP), which
		 * may be not so unique as GetEntryID(). For example, if an
		 * entry exists in the roster, but it has also requested auth,
		 * there would be two entries with the same human-readable ID,
		 * but they would still be distinguished by the result of the
		 * GetEntryID() function.
		 *
		 * Various operations like buddy searches (in protocols that
		 * support this feature like Skype or ICQ) are expected to
		 * operate on strings that are among possible return values of
		 * this function. Also, when initiating entry addition, the
		 * entry is expected to be identified by a similar string.
		 *
		 * The default implementation returns GetEntryID() as an unicode
		 * string.
		 *
		 * @return Human-readable persistent ID of this entry.
		 *
		 * @sa GetEntryID()
		 */
		virtual QString GetHumanReadableID () const
		{
			return GetEntryID ();
		}

		/** @brief Returns the list of human-readable names of the
		 * groups that this entry belongs to.
		 *
		 * @return The list of groups of this item.
		 */
		virtual QStringList Groups () const = 0;

		/** @brief Sets the list of groups this item belongs to.
		 *
		 * If updating the list of groups is not applicable, this
		 * function should do nothing.
		 *
		 * @param[in] groups The new list of groups.
		 */
		virtual void SetGroups (const QStringList& groups) = 0;

		/** @brief Returns the list of destination variants.
		 *
		 * For example, for an entry representing a contact in XMPP
		 * protocol variants would be the list of resources for the
		 * contact.
		 *
		 * Strings in the list should not be null, though they may be
		 * empty. There should be no duplicates in returned list.
		 *
		 * The strings in the returned list should be sorted in
		 * descending order according to importance. For example, for
		 * XMPP protocol, the first variant should be the resource with
		 * the highest priority.
		 *
		 * @return The list of variants of this entry.
		 */
		virtual QStringList Variants () const = 0;

		/** @brief Creates the message of the given type to the given
		 * variant.
		 *
		 * Variant is a string from the list returned by Variants(). If
		 * a different string is passed, particularly, a null one, the
		 * implementation must choose the best variant itself: for
		 * example, the resource with the highest priority in XMPP.
		 *
		 * No message should be sent as result of CreateMessage().
		 * Instead, one would later call IMessage::Send() on the
		 * returned message.
		 *
		 * @param[in] type The type of the message.
		 * @param[in] variant The variant to send to.
		 * @param[in] body Message boxy.
		 * @return The prepared message.
		 *
		 * @sa Variants()
		 */
		virtual IMessage* CreateMessage (IMessage::Type type,
				const QString& variant,
				const QString& body) = 0;

		/** @brief Returns all already sent or received messages.
		 *
		 * Returns the list of all messages sent or received during the
		 * session.
		 *
		 * If the entry represents a MUC, all the messages in the
		 * returned list should have "IN" direction.
		 *
		 * @return The list of messages.
		 */
		virtual QList<IMessage*> GetAllMessages () const = 0;

		/** @brief Purges messages before the given date.
		 *
		 * This function should purge all the messages before the given
		 * date. After the call, the corresponding messages should not
		 * appear in the result of GetAllMessages() function. It's also
		 * suggested to remove them from any internal memory storage to
		 * conserve memory.
		 *
		 * If before is an invalid date, this function should purge all
		 * messages.
		 *
		 * @param[in] before The date before which messages should be
		 * purged.
		 */
		virtual void PurgeMessages (const QDateTime& before) = 0;

		/** @brief Notifies about our chat participation state change.
		 *
		 * If variant is a null string, a variant with the highest
		 * priority should be used.
		 *
		 * @param[in] state Our new chat participation state.
		 * @param[in] variant Target variant.
		 */
		virtual void SetChatPartState (ChatPartState state,
				const QString& variant) = 0;

		/** @brief Returns the current status of a variant of the item.
		 *
		 * Since different variants may have different status, this
		 * function should return the proper status for the given
		 * variant. If no such variant exists, an empty status structure
		 * should be returned.
		 *
		 * @param[in] variant The variant to return status for or null
		 * string for most important variant.
		 * @return The current status.
		 */
		virtual EntryStatus GetStatus (const QString& variant = QString ()) const = 0;

		/** @brief Returns the avatar of this item.
		 *
		 * @return The image with the avatar.
		 */
		virtual QImage GetAvatar () const = 0;

		/** @brief Requests the entry to show dialog with info about it.
		 */
		virtual void ShowInfo () = 0;

		/** @brief Returns the list of actions for the item.
		 *
		 * The list is showed, for example, when user calls the context
		 * menu on the item, or such. You may want to place actions like
		 * "Info", etc, in this list.
		 *
		 * @return The list of actions.
		 */
		virtual QList<QAction*> GetActions () const = 0;

		/** @brief Returns the client information for the given variant.
		 *
		 * The returned map should have the following keys:
		 * - client_type
		 *   The corresponding value is a QString with a client ID.
		 * - client_name
		 *   The corresponding value is a QString with human-readable
		 *   name of the client.
		 * - client_version
		 *   The corresponding value is a QString with human-readable
		 *   version of the client.
		 * - priority
		 *   The corresponding value is a int with the priority of the
		 *   variant. The priority spans from -1024 to 1024, with
		 *   negative values indicating that the message won't be
		 *   delivered to this resource unless it was explicitly created
		 *   to be targeted at this resource.
		 *
		 * @param[in] variant Variant for which to return the client
		 * info.
		 *
		 * @return Human-readable client name of the variant.
		 */
		virtual QMap<QString, QVariant> GetClientInfo (const QString& variant) const = 0;

		/** @brief Called whenever new messages are read.
		 *
		 * This function is called by Azoth Core whenever any unread
		 * messages that could be present in this entry are read. For
		 * example, this may happen when user opens the chat tab with
		 * this entry.
		 *
		 * Please note that this function is always called, even when
		 * there are no messages at all, for example.
		 */
		virtual void MarkMsgsRead () = 0;

		/** @brief Called by Azoth when the chat with the entry is closed.
		 */
		virtual void ChatTabClosed () = 0;

		/** @brief This signal should be emitted whenever a new message
		 * is received.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 *
		 * @param[out] msg The message that was just received.
		 */
		virtual void gotMessage (QObject *msg) = 0;

		/** @brief This signal should be emitted whenever the status of
		 * a variant in this entry changes.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 *
		 * @param[out] st The new status of this entry.
		 * @param[out] variant What variant is subject to change.
		 */
		virtual void statusChanged (const EntryStatus& st,
				const QString& variant) = 0;

		/** @brief This signal should be emitted whenever the list of
		 * available variants changes.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 *
		 * @param[out] newVars The list of new variants, as
		 * returned by GetVariants().
		 */
		virtual void availableVariantsChanged (const QStringList& newVars) = 0;

		/** @brief This signal should be emitted whenever the avatar of
		 * this item is changed.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 */
		virtual void avatarChanged (const QImage&) = 0;

		/** @brief This signal should be emitted whenever the entry
		 * changes name.
		 *
		 * This signal should be emitted both if the name of the entry
		 * changes as the result of our actions (particularly, the
		 * SetEntryName() method) and as a result of some other event,
		 * for example, a roster push in XMPP.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 *
		 * @param[out] name The new name of this entry.
		 */
		virtual void nameChanged (const QString& name) = 0;

		/** @brief This signal should be emitted whenever the entry's
		 * groups are changed.
		 *
		 * This signal should be emitted both if the list of groups
		 * changes as the result of our actions (particularly, the
		 * SetGroups() method) and as a result of some other event, for
		 * example, a roster push in XMPP.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 *
		 * @param[out] groups The new list of groups of this entry.
		 */
		virtual void groupsChanged (const QStringList& groups) = 0;

		/** @brief This signal should be emitted whenever the chat
		 * participation state of this entry changes.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 * @param[out] state The new chat state.
		 * @param[out] variant The variant that this change applies to,
		 * may be a null string if not applicable.
		 */
		virtual void chatPartStateChanged (const ChatPartState& state,
				const QString& variant) = 0;

		/** @brief This signal should be emitted if it's a MUC
		 * participant and his role/affiliation changes.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 */
		virtual void permsChanged () = 0;

		/** @brief This signal should be emitted when the entry changes.
		 *
		 * This signal should be emitted only if no other signals apply
		 * (even those from IAdvancedCLEntry or such): it is some kind
		 * of a fall-back notification.
		 *
		 * @note This function is expected to be a signal in subclasses.
		 */
		virtual void entryGenerallyChanged () = 0;
	};
}
}

Q_DECLARE_METATYPE (LeechCraft::Azoth::EntryStatus);
Q_DECLARE_OPERATORS_FOR_FLAGS (LeechCraft::Azoth::ICLEntry::Features);
Q_DECLARE_INTERFACE (LeechCraft::Azoth::ICLEntry,
		"org.Deviant.LeechCraft.Azoth.ICLEntry/1.0");
