/*
 MIT License

 Copyright (c) 2017 MessageKit

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.

 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 AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 */

import Foundation

public protocol MessagesLayoutDelegate: class {

    func avatarAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> AvatarAlignment

    func cellTopLabelAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> LabelAlignment

    func cellBottomLabelAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> LabelAlignment

    func avatarSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize

    func headerViewSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize

    func footerViewSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize

}

public extension MessagesLayoutDelegate {

    func avatarAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> AvatarAlignment {
        return .cellBottom
    }

    func cellTopLabelAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> LabelAlignment {
        guard let dataSource = messagesCollectionView.messagesDataSource else { return .cellCenter }
        return dataSource.isFromCurrentSender(message: message) ? .messageTrailing : .messageLeading
    }

    func cellBottomLabelAlignment(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> LabelAlignment {
        guard let dataSource = messagesCollectionView.messagesDataSource else { return .cellCenter }
        return dataSource.isFromCurrentSender(message: message) ? .messageLeading : .messageTrailing
    }

    func avatarSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize {
        return CGSize(width: 30, height: 30)
    }

    func headerViewSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize {
        guard let displayDelegate = messagesCollectionView.messagesDisplayDelegate else { return .zero }
        let shouldDisplay = displayDelegate.shouldDisplayHeader(for: message, at: indexPath, in: messagesCollectionView)
        return shouldDisplay ? CGSize(width: messagesCollectionView.bounds.width, height: 12) : .zero
    }

    func footerViewSize(for message: MessageType, at indexPath: IndexPath, in messagesCollectionView: MessagesCollectionView) -> CGSize {
        return .zero
    }

}