Swiftgram/TelegramCore/PendingMessageUploadedContent.swift

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

enum PendingMessageUploadedContent {
    case text(String)
    case media(Api.InputMedia)
    case forward(ForwardSourceInfoAttribute)
    case chatContextResult(OutgoingChatContextResultMessageAttribute)
}

enum PendingMessageUploadedContentResult {
    case progress(Float)
    case content(Message, PendingMessageUploadedContent)
}

func uploadedMessageContent(network: Network, postbox: Postbox, message: Message) -> Signal<PendingMessageUploadedContentResult, NoError> {
    var outgoingChatContextResultAttribute: OutgoingChatContextResultMessageAttribute?
    for attribute in message.attributes {
        if let attribute = attribute as? OutgoingChatContextResultMessageAttribute {
            outgoingChatContextResultAttribute = attribute
        }
    }
    
    if let forwardInfo = message.forwardInfo {
        var forwardSourceInfo: ForwardSourceInfoAttribute?
        for attribute in message.attributes {
            if let attribute = attribute as? ForwardSourceInfoAttribute {
                forwardSourceInfo = attribute
            }
        }
        if let forwardSourceInfo = forwardSourceInfo {
            return .single(.content(message, .forward(forwardSourceInfo)))
        } else {
            return .never()
        }
    } else if let outgoingChatContextResultAttribute = outgoingChatContextResultAttribute {
        return .single(.content(message, .chatContextResult(outgoingChatContextResultAttribute)))
    } else if let media = message.media.first {
        if let image = media as? TelegramMediaImage, let largestRepresentation = largestImageRepresentation(image.representations) {
            return uploadedMediaImageContent(network: network, postbox: postbox, image: image, message: message)
        } else if let file = media as? TelegramMediaFile {
            if let resource = file.resource as? CloudDocumentMediaResource {
                return .single(.content(message, .media(Api.InputMedia.inputMediaDocument(id: Api.InputDocument.inputDocument(id: resource.fileId, accessHash: resource.accessHash), caption: message.text))))
            } else {
                return uploadedMediaFileContent(network: network, postbox: postbox, file: file, message: message)
            }
        } else {
            return .single(.content(message, .text(message.text)))
        }
    } else {
        return .single(.content(message, .text(message.text)))
    }
}

private func uploadedMediaImageContent(network: Network, postbox: Postbox, image: TelegramMediaImage, message: Message) -> Signal<PendingMessageUploadedContentResult, NoError> {
    if let largestRepresentation = largestImageRepresentation(image.representations) {
        return multipartUpload(network: network, postbox: postbox, resource: largestRepresentation.resource)
            |> map { next -> PendingMessageUploadedContentResult in
                switch next {
                    case let .progress(progress):
                        return .progress(progress)
                    case let .inputFile(file):
                        return .content(message, .media(Api.InputMedia.inputMediaUploadedPhoto(flags: 0, file: file, caption: message.text, stickers: nil)))
                }
            }
    } else {
        return .single(.content(message, .text(message.text)))
    }
}

private func inputDocumentAttributesFromFile(_ file: TelegramMediaFile) -> [Api.DocumentAttribute] {
    var attributes: [Api.DocumentAttribute] = []
    for attribute in file.attributes {
        switch attribute {
            case .Animated:
                attributes.append(.documentAttributeAnimated)
            case let .FileName(fileName):
                attributes.append(.documentAttributeFilename(fileName: fileName))
            case let .ImageSize(size):
                attributes.append(.documentAttributeImageSize(w: Int32(size.width), h: Int32(size.height)))
            case let .Sticker(displayText):
                attributes.append(.documentAttributeSticker(flags: 0, alt: displayText, stickerset: .inputStickerSetEmpty, maskCoords: nil))
            case .HasLinkedStickers:
                attributes.append(.documentAttributeHasStickers)
            case let .Video(duration, size):
                attributes.append(.documentAttributeVideo(duration: Int32(duration), w: Int32(size.width), h: Int32(size.height)))
            case let .Audio(isVoice, duration, title, performer, waveform):
                var flags: Int32 = 0
                if isVoice {
                    flags |= Int32(1 << 10)
                }
                if let _ = title {
                    flags |= Int32(1 << 0)
                }
                if let _ = performer {
                    flags |= Int32(1 << 1)
                }
                var waveformBuffer: Buffer?
                if let waveform = waveform {
                    flags |= Int32(1 << 2)
                    waveformBuffer = Buffer(data: waveform.makeData())
                }
                attributes.append(.documentAttributeAudio(flags: flags, duration: Int32(duration), title: title, performer: performer, waveform: waveformBuffer))
        }
    }
    return attributes
}

private func uploadedMediaFileContent(network: Network, postbox: Postbox, file: TelegramMediaFile, message: Message) -> Signal<PendingMessageUploadedContentResult, NoError> {
    return multipartUpload(network: network, postbox: postbox, resource: file.resource)
        |> map { next -> PendingMessageUploadedContentResult in
            switch next {
                case let .progress(progress):
                    return .progress(progress)
                case let .inputFile(inputFile):
                    return .content(message, .media(Api.InputMedia.inputMediaUploadedDocument(flags: 0, file: inputFile, mimeType: file.mimeType, attributes: inputDocumentAttributesFromFile(file), caption: message.text, stickers: nil)))
            }
        }
}