import Foundation
#if os(macOS)
    import PostboxMac
    import SwiftSignalKitMac
    import MtProtoKitMac
#else
    import Postbox
    import SwiftSignalKit
    import MtProtoKitDynamic
#endif

public enum UpdatePeerPhotoStatus {
    case progress(Float)
    case complete([TelegramMediaImageRepresentation])
}

public enum UploadPeerPhotoError {
    case generic
}

public func updateAccountPhoto(account:Account, resource: MediaResource?) -> Signal<UpdatePeerPhotoStatus, UploadPeerPhotoError> {
    return updatePeerPhoto(account: account, peerId: account.peerId, photo: resource.flatMap({ uploadedPeerPhoto(account: account, resource: $0) }))
}

public struct UploadedPeerPhotoData {
    fileprivate let resource: MediaResource
    fileprivate let content: UploadedPeerPhotoDataContent
}

private enum UploadedPeerPhotoDataContent {
    case result(MultipartUploadResult)
    case error
}

public func uploadedPeerPhoto(account: Account, resource: MediaResource) -> Signal<UploadedPeerPhotoData, NoError> {
    return multipartUpload(network: account.network, postbox: account.postbox, source: .resource(.standalone(resource: resource)), encrypt: false, tag: TelegramMediaResourceFetchTag(statsCategory: .image), hintFileSize: nil, hintFileIsLarge: false)
    |> map { result -> UploadedPeerPhotoData in
        return UploadedPeerPhotoData(resource: resource, content: .result(result))
    }
    |> `catch` { _ -> Signal<UploadedPeerPhotoData, NoError> in
        return .single(UploadedPeerPhotoData(resource: resource, content: .error))
    }
}

public func updatePeerPhoto(account: Account, peerId: PeerId, photo: Signal<UploadedPeerPhotoData, NoError>?) -> Signal<UpdatePeerPhotoStatus, UploadPeerPhotoError> {
     return account.postbox.loadedPeerWithId(peerId)
        |> mapError {_ in return .generic}
        |> mapToSignal { peer -> Signal<UpdatePeerPhotoStatus, UploadPeerPhotoError> in
        if let photo = photo {
            return photo
                |> mapError { _ -> UploadPeerPhotoError in return .generic }
                |> mapToSignal { result -> Signal<(UpdatePeerPhotoStatus, MediaResource?), UploadPeerPhotoError> in
                    switch result.content {
                        case .error:
                            return .fail(.generic)
                        case let .result(resultData):
                            switch resultData {
                                case let .progress(progress):
                                    return .single((.progress(progress), result.resource))
                                case let .inputFile(file):
                                    if peer is TelegramUser {
                                        return account.network.request(Api.functions.photos.uploadProfilePhoto(file: file))
                                        |> mapError {_ in return UploadPeerPhotoError.generic}
                                        |> mapToSignal { photo -> Signal<(UpdatePeerPhotoStatus, MediaResource?), UploadPeerPhotoError> in
                                            
                                            let representations:[TelegramMediaImageRepresentation]
                                            switch photo {
                                            case let .photo(photo: apiPhoto, users: _):
                                                switch apiPhoto {
                                                case .photoEmpty:
                                                    representations = []
                                                case let .photo(photo):
                                                    var sizes = photo.sizes
                                                    if sizes.count == 3 {
                                                        sizes.remove(at: 1)
                                                    }
                                                    representations = telegramMediaImageRepresentationsFromApiSizes(sizes)
                                                    if let resource = result.resource as? LocalFileReferenceMediaResource {
                                                        if let data = try? Data(contentsOf: URL(fileURLWithPath: resource.localFilePath)) {
                                                            for representation in representations {
                                                                account.postbox.mediaBox.storeResourceData(representation.resource.id, data: data)
                                                            }
                                                        }
                                                    }
                                                   
                                                }
                                            }
                                            return account.postbox.transaction { transaction -> (UpdatePeerPhotoStatus, MediaResource?) in
                                                if let peer = transaction.getPeer(peer.id) {
                                                    updatePeers(transaction: transaction, peers: [peer], update: { (_, peer) -> Peer? in
                                                        if let peer = peer as? TelegramUser {
                                                            return peer.withUpdatedPhoto(representations)
                                                        } else {
                                                            return peer
                                                        }
                                                    })
                                                }
                                                return (.complete(representations), result.resource)
                                                
                                            } |> mapError {_ in return UploadPeerPhotoError.generic}
                                        }
                                    } else {
                                        let request: Signal<Api.Updates, MTRpcError>
                                        if let peer = peer as? TelegramGroup {
                                            request = account.network.request(Api.functions.messages.editChatPhoto(chatId: peer.id.id, photo: .inputChatUploadedPhoto(file: file)))
                                        } else if let peer = peer as? TelegramChannel, let inputChannel = apiInputChannel(peer) {
                                            request = account.network.request(Api.functions.channels.editPhoto(channel: inputChannel, photo: .inputChatUploadedPhoto(file: file)))
                                        } else {
                                            assertionFailure()
                                            request = .complete()
                                        }
                                        
                                        return request |> mapError {_ in return UploadPeerPhotoError.generic} |> mapToSignal { updates -> Signal<(UpdatePeerPhotoStatus, MediaResource?), UploadPeerPhotoError> in
                                            account.stateManager.addUpdates(updates)
                                            for chat in updates.chats {
                                                if chat.peerId == peerId {
                                                    if let groupOrChannel = parseTelegramGroupOrChannel(chat: chat) {
                                                        return account.postbox.transaction { transaction -> (UpdatePeerPhotoStatus, MediaResource?) in
                                                            updatePeers(transaction: transaction, peers: [groupOrChannel], update: { _, updated in
                                                                return updated
                                                            })
                                                            return (.complete(groupOrChannel.profileImageRepresentations), result.resource)
                                                        } |> mapError { _ in return .generic }
                                                    }
                                                }
                                            }
                                            
                                            return .fail(.generic)
                                        }
                                    }
                                default:
                                    return .fail(.generic)
                            }
                    }
                }
                |> map { result, resource -> UpdatePeerPhotoStatus in
                    switch result {
                        case let .complete(representations):
                            if let resource = resource as? LocalFileReferenceMediaResource {
                                if let data = try? Data(contentsOf: URL(fileURLWithPath: resource.localFilePath)) {
                                    for representation in representations {
                                        account.postbox.mediaBox.storeResourceData(representation.resource.id, data: data)
                                    }
                                }
                            }
                        default:
                            break
                    }
                    return result
                }
        } else {
            if let _ = peer as? TelegramUser {
                return account.network.request(Api.functions.photos.updateProfilePhoto(id: Api.InputPhoto.inputPhotoEmpty))
                    |> `catch` { _ -> Signal<Api.UserProfilePhoto, UploadPeerPhotoError> in
                        return .fail(.generic)
                    }
                    |> mapToSignal { _ -> Signal<UpdatePeerPhotoStatus, UploadPeerPhotoError> in
                        return .single(.complete([]))
                    }
            } else {
                let request: Signal<Api.Updates, MTRpcError>
                if let peer = peer as? TelegramGroup {
                    request = account.network.request(Api.functions.messages.editChatPhoto(chatId: peer.id.id, photo: .inputChatPhotoEmpty))
                } else if let peer = peer as? TelegramChannel, let inputChannel = apiInputChannel(peer) {
                    request = account.network.request(Api.functions.channels.editPhoto(channel: inputChannel, photo: .inputChatPhotoEmpty))
                } else {
                    assertionFailure()
                    request = .complete()
                }
                
                return request |> mapError {_ in return UploadPeerPhotoError.generic} |> mapToSignal { updates -> Signal<UpdatePeerPhotoStatus, UploadPeerPhotoError> in
                    account.stateManager.addUpdates(updates)
                    for chat in updates.chats {
                        if chat.peerId == peerId {
                            if let groupOrChannel = parseTelegramGroupOrChannel(chat: chat) {
                                return account.postbox.transaction { transaction -> UpdatePeerPhotoStatus in
                                    updatePeers(transaction: transaction, peers: [groupOrChannel], update: { _, updated in
                                        return updated
                                    })
                                    return .complete(groupOrChannel.profileImageRepresentations)
                                } |> mapError { _ in return .generic }
                            }
                        }
                    }
                    
                    return .fail(.generic)
                }
            }
        }
    }
}

public func removeAccountPhoto(network: Network, reference: TelegramMediaImageReference?) -> Signal<Void, NoError> {
    if let reference = reference {
        switch reference {
        case let .cloud(imageId, accessHash, fileReference):
            if let fileReference = fileReference {
                return network.request(Api.functions.photos.deletePhotos(id: [.inputPhoto(id: imageId, accessHash: accessHash, fileReference: Buffer(data: fileReference))]))
                |> `catch` { _ -> Signal<[Int64], NoError> in
                    return .single([])
                }
                |> mapToSignal { _ -> Signal<Void, NoError> in
                    return .complete()
                }
            } else {
                return .complete()
            }
        }
    } else {
        let api = Api.functions.photos.updateProfilePhoto(id: Api.InputPhoto.inputPhotoEmpty)
        return network.request(api) |> map { _ in } |> retryRequest
    }
}