session-ios/Signal/src/ViewControllers/MessageMetadataViewController.swift

//
//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
//

import Foundation

class MessageMetadataViewController: OWSViewController {

    static let TAG = "[MessageMetadataViewController]"
    let TAG = "[MessageMetadataViewController]"

    // MARK: Properties

    let contactsManager: OWSContactsManager
    
    let databaseConnection: YapDatabaseConnection

    var message: TSMessage

    var mediaMessageView: MediaMessageView?

    var scrollView: UIScrollView?
    var contentView: UIView?

    var dataSource: DataSource?
    var attachmentStream: TSAttachmentStream?
    var messageBody: String?

    // MARK: Initializers

    @available(*, unavailable, message:"use message: constructor instead.")
    required init?(coder aDecoder: NSCoder) {
        self.contactsManager = Environment.getCurrent().contactsManager
        self.message = TSMessage()
        self.databaseConnection = TSStorageManager.shared().newDatabaseConnection()!
        super.init(coder: aDecoder)
        owsFail("\(self.TAG) invalid constructor")
    }

    required init(message: TSMessage) {
        self.contactsManager = Environment.getCurrent().contactsManager
        self.message = message
        self.databaseConnection = TSStorageManager.shared().newDatabaseConnection()!
        super.init(nibName: nil, bundle: nil)
    }

    // MARK: View Lifecycle

    override func viewDidLoad() {
        super.viewDidLoad()

        self.databaseConnection.beginLongLivedReadTransaction()
        updateDBConnectionAndMessageToLatest()

        self.navigationItem.title = NSLocalizedString("MESSAGE_METADATA_VIEW_TITLE",
                                                      comment: "Title for the 'message metadata' view.")

        createViews()

        NotificationCenter.default.addObserver(self,
            selector:#selector(yapDatabaseModified),
            name:NSNotification.Name.YapDatabaseModified,
            object:nil)
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        mediaMessageView?.viewWillAppear(animated)
    }

    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)

        mediaMessageView?.viewWillDisappear(animated)
    }

    // MARK: - Create Views

    private func createViews() {
        view.backgroundColor = UIColor.white

        let scrollView = UIScrollView()
        self.scrollView = scrollView
        view.addSubview(scrollView)
        scrollView.autoPinWidthToSuperview(withMargin:0)
        scrollView.autoPin(toTopLayoutGuideOf: self, withInset:0)

        // See notes on how to use UIScrollView with iOS Auto Layout:
        //
        // https://developer.apple.com/library/content/releasenotes/General/RN-iOSSDK-6_0/
        let contentView = UIView.container()
        self.contentView = contentView
        scrollView.addSubview(contentView)
        contentView.autoPinLeadingToSuperView()
        contentView.autoPinTrailingToSuperView()
        contentView.autoPinEdge(toSuperviewEdge:.top)
        contentView.autoPinEdge(toSuperviewEdge:.bottom)
        scrollView.layoutMargins = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)

        let hasAttachment = message.attachmentIds.count > 0

        if hasAttachment {
            let footer = UIToolbar()
            footer.barTintColor = UIColor.ows_materialBlue()
            view.addSubview(footer)
            footer.autoPinWidthToSuperview(withMargin:0)
            footer.autoPinEdge(.top, to:.bottom, of:scrollView)
            footer.autoPin(toBottomLayoutGuideOf: self, withInset:0)

            footer.items = [
                UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil),
                UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(shareButtonPressed)),
                UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
            ]
        } else {
            scrollView.autoPin(toBottomLayoutGuideOf: self, withInset:0)
        }

        updateContent()
    }

    private func updateContent() {
        guard let contentView = contentView else {
            owsFail("\(TAG) Missing contentView")
            return
        }

        // Remove any existing content views.
        for subview in contentView.subviews {
            subview.removeFromSuperview()
        }

        var rows = [UIView]()
        let contactsManager = Environment.getCurrent().contactsManager!
        let thread = message.thread

        // Sender?
        if let incomingMessage = message as? TSIncomingMessage {
            let senderId = incomingMessage.authorId
            let senderName = contactsManager.contactOrProfileName(forPhoneIdentifier:senderId)
            rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_SENDER",
                                                         comment: "Label for the 'sender' field of the 'message metadata' view."),
                                 value:senderName))
        }

        // Recipient(s)
        if let outgoingMessage = message as? TSOutgoingMessage {

            // TODO: It'd be nice to inset these dividers from the edge of the screen.
            let addDivider = {
                let divider = UIView()
                divider.backgroundColor = UIColor(white:0.9, alpha:1.0)
                divider.autoSetDimension(.height, toSize:0.5)
                rows.append(divider)
            }

            addDivider()

            for recipientId in thread.recipientIdentifiers {
                let recipientStatus = self.recipientStatus(forOutgoingMessage: outgoingMessage, recipientId: recipientId)

                let cell = ContactTableViewCell()
                cell.configure(withRecipientId: recipientId, contactsManager: self.contactsManager)
                let statusLabel = UILabel()
                statusLabel.text = recipientStatus
                statusLabel.textColor = UIColor.ows_darkGray()
                statusLabel.font = UIFont.ows_footnote()
                statusLabel.sizeToFit()
                cell.accessoryView = statusLabel
                cell.autoSetDimension(.height, toSize:ContactTableViewCell.rowHeight())
                cell.setContentHuggingLow()
                rows.append(cell)

                addDivider()
            }
        }

        rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_SENT_DATE_TIME",
                                                     comment: "Label for the 'sent date & time' field of the 'message metadata' view."),
                             value:DateUtil.formatPastTimestampRelativeToNow(message.timestamp)))

        if let _ = message as? TSIncomingMessage {
            rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_RECEIVED_DATE_TIME",
                                                         comment: "Label for the 'received date & time' field of the 'message metadata' view."),
                                 value:DateUtil.formatPastTimestampRelativeToNow(message.timestampForSorting())))
        }

        // TODO: We could include the "disappearing messages" state here.

        if message.attachmentIds.count > 0 {
            rows += addAttachmentRows()
        } else if let messageBody = message.body {
            // TODO: We should also display "oversize text messages" in a
            //       similar way.
            if messageBody.characters.count > 0 {
                self.messageBody = messageBody

                rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_BODY_LABEL",
                                                             comment: "Label for the message body in the 'message metadata' view."),
                                     value:""))

                let bodyLabel = UILabel()
                bodyLabel.textColor = UIColor.black
                bodyLabel.font = UIFont.ows_regularFont(withSize:14)
                bodyLabel.text = messageBody
                bodyLabel.numberOfLines = 0
                bodyLabel.lineBreakMode = .byWordWrapping
                rows.append(bodyLabel)
            } else {
                // Neither attachment nor body.
                owsFail("\(self.TAG) Message has neither attachment nor body.")
                rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_NO_ATTACHMENT_OR_BODY",
                                                             comment: "Label for messages without a body or attachment in the 'message metadata' view."),
                                     value:""))
            }
        }

        var lastRow: UIView?
        for row in rows {
            contentView.addSubview(row)
            row.autoPinLeadingToSuperView()
            row.autoPinTrailingToSuperView()

            if let lastRow = lastRow {
                row.autoPinEdge(.top, to:.bottom, of:lastRow, withOffset:5)
            } else {
                row.autoPinEdge(toSuperviewEdge:.top, withInset:20)
            }

            lastRow = row
        }
        if let lastRow = lastRow {
            lastRow.autoPinEdge(toSuperviewEdge:.bottom, withInset:20)
        }

        if let mediaMessageView = mediaMessageView {
            mediaMessageView.autoPinToSquareAspectRatio()
        }
    }

    private func addAttachmentRows() -> [UIView] {
        var rows = [UIView]()

        guard let attachmentId = message.attachmentIds[0] as? String else {
            owsFail("Invalid attachment")
            return rows
        }

        guard let attachment = TSAttachment.fetch(uniqueId:attachmentId) else {
            owsFail("Missing attachment")
            return rows
        }

        let contentType = attachment.contentType
        rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_ATTACHMENT_MIME_TYPE",
                                                     comment: "Label for the MIME type of attachments in the 'message metadata' view."),
                             value:contentType))

        if let sourceFilename = attachment.sourceFilename {
            rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_SOURCE_FILENAME",
                                                         comment: "Label for the original filename of any attachment in the 'message metadata' view."),
                                 value:sourceFilename))
        }

        guard let attachmentStream = attachment as? TSAttachmentStream else {
            rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_ATTACHMENT_NOT_YET_DOWNLOADED",
                                                         comment: "Label for 'not yet downloaded' attachments in the 'message metadata' view."),
                                 value:""))
            return rows
        }
        self.attachmentStream = attachmentStream

        if let filePath = attachmentStream.filePath() {
            dataSource = DataSourcePath.dataSource(withFilePath:filePath)
        }

        guard let dataSource = dataSource else {
            rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_ATTACHMENT_MISSING_FILE",
                                                         comment: "Label for 'missing' attachments in the 'message metadata' view."),
                                 value:""))
            return rows
        }

        let fileSize = dataSource.dataLength()
        rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_ATTACHMENT_FILE_SIZE",
                                                     comment: "Label for file size of attachments in the 'message metadata' view."),
                             value:ViewControllerUtils.formatFileSize(UInt(fileSize))))

        if let dataUTI = MIMETypeUtil.utiType(forMIMEType:contentType) {
            if attachment.isVoiceMessage() {
                rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_VOICE_MESSAGE",
                                                             comment: "Label for voice messages of the 'message metadata' view."),
                                     value:""))
            } else {
                rows.append(valueRow(name: NSLocalizedString("MESSAGE_METADATA_VIEW_MEDIA",
                                                             comment: "Label for media messages of the 'message metadata' view."),
                                     value:""))
            }
            let attachment = SignalAttachment(dataSource : dataSource, dataUTI: dataUTI)
            let mediaMessageView = MediaMessageView(attachment:attachment)
            self.mediaMessageView = mediaMessageView
            rows.append(mediaMessageView)
        }
        return rows
    }

    private func recipientStatus(forOutgoingMessage message: TSOutgoingMessage, recipientId: String) -> String {
        // Legacy messages don't have "recipient read" state or "per-recipient delivery" state,
        // so we fall back to `TSOutgoingMessageState` which is not per-recipient and therefore
        // might be misleading.

        let recipientReadMap = message.recipientReadMap
        if let readTimestamp = recipientReadMap[recipientId] {
            assert(message.messageState == .sentToService)
            return NSLocalizedString("MESSAGE_STATUS_READ", comment:"message footer for read messages").rtlSafeAppend(" ", referenceView:self.view)
            .rtlSafeAppend(
                DateUtil.formatPastTimestampRelativeToNow(readTimestamp.uint64Value), referenceView:self.view)
        }

        let recipientDeliveryMap = message.recipientDeliveryMap
        if let deliveryTimestamp = recipientDeliveryMap[recipientId] {
            assert(message.messageState == .sentToService)
            return NSLocalizedString("MESSAGE_STATUS_DELIVERED",
                                     comment:"message status for message delivered to their recipient.").rtlSafeAppend(" ", referenceView:self.view)
                .rtlSafeAppend(
                    DateUtil.formatPastTimestampRelativeToNow(deliveryTimestamp.uint64Value), referenceView:self.view)
        }

        if message.wasDelivered {
            return NSLocalizedString("MESSAGE_STATUS_DELIVERED",
                                     comment:"message status for message delivered to their recipient.")
        }

        if message.messageState == .unsent {
            return NSLocalizedString("MESSAGE_STATUS_FAILED", comment:"message footer for failed messages")
        } else if (message.messageState == .sentToService ||
            message.wasSent(toRecipient:recipientId)) {
            return
                NSLocalizedString("MESSAGE_STATUS_SENT",
                                  comment:"message footer for sent messages")
        } else if message.hasAttachments() {
            assert(message.messageState == .attemptingOut)

            return NSLocalizedString("MESSAGE_STATUS_UPLOADING",
                                     comment:"message footer while attachment is uploading")
        } else {
            assert(message.messageState == .attemptingOut)

            return NSLocalizedString("MESSAGE_STATUS_SENDING",
                                     comment:"message status while message is sending.")
        }
    }

    private func nameLabel(text: String) -> UILabel {
        let label = UILabel()
        label.textColor = UIColor.black
        label.font = UIFont.ows_mediumFont(withSize:14)
        label.text = text
        label.setContentHuggingHorizontalHigh()
        return label
    }

    private func valueLabel(text: String) -> UILabel {
        let label = UILabel()
        label.textColor = UIColor.black
        label.font = UIFont.ows_regularFont(withSize:14)
        label.text = text
        label.setContentHuggingHorizontalLow()
        return label
    }

    private func valueRow(name: String, value: String, subtitle: String = "") -> UIView {
        let row = UIView.container()
        let nameLabel = self.nameLabel(text:name)
        let valueLabel = self.valueLabel(text:value)
        row.addSubview(nameLabel)
        row.addSubview(valueLabel)
        nameLabel.autoPinLeadingToSuperView(withMargin:20)
        valueLabel.autoPinTrailingToSuperView(withMargin:20)
        valueLabel.autoPinLeading(toTrailingOf:nameLabel, margin: 10)
        nameLabel.autoPinEdge(toSuperviewEdge:.top)
        valueLabel.autoPinEdge(toSuperviewEdge:.top)

        if subtitle.characters.count > 0 {
            let subtitleLabel = self.valueLabel(text:subtitle)
            subtitleLabel.textColor = UIColor.ows_darkGray()
            row.addSubview(subtitleLabel)
            subtitleLabel.autoPinTrailingToSuperView()
            subtitleLabel.autoPinLeading(toTrailingOf:nameLabel, margin: 10)
            subtitleLabel.autoPinEdge(.top, to:.bottom, of:valueLabel, withOffset:1)
            subtitleLabel.autoPinEdge(toSuperviewEdge:.bottom)
        } else if value.characters.count > 0 {
            valueLabel.autoPinEdge(toSuperviewEdge:.bottom)
        } else {
            nameLabel.autoPinEdge(toSuperviewEdge:.bottom)
        }

        return row
    }

    // MARK: - Actions

    func shareButtonPressed() {
        if let messageBody = messageBody {
            UIPasteboard.general.string = messageBody
            return
        }

        guard let attachmentStream = attachmentStream else {
            Logger.error("\(TAG) Message has neither attachment nor message body.")
            return
        }
        AttachmentSharing.showShareUI(forAttachment:attachmentStream)
    }

    func copyToPasteboard() {
        if let messageBody = messageBody {
            UIPasteboard.general.string = messageBody
            return
        }

        guard let attachmentStream = attachmentStream else {
            Logger.error("\(TAG) Message has neither attachment nor message body.")
            return
        }
        guard let utiType = MIMETypeUtil.utiType(forMIMEType:attachmentStream.contentType) else {
            Logger.error("\(TAG) Attachment has invalid MIME type: \(attachmentStream.contentType).")
            return
        }
        guard let dataSource = dataSource else {
            Logger.error("\(TAG) Attachment missing data source.")
            return
        }
        let data = dataSource.data()
        UIPasteboard.general.setData(data, forPasteboardType:utiType)
    }

    // MARK: - Actions

    // This method should be called after self.databaseConnection.beginLongLivedReadTransaction().
    private func updateDBConnectionAndMessageToLatest() {

        AssertIsOnMainThread()

        self.databaseConnection.read { transaction in
            guard let newMessage = TSInteraction.fetch(uniqueId:self.message.uniqueId, transaction:transaction) as? TSMessage else {
                Logger.error("\(self.TAG) Couldn't reload message.")
                return
            }
            self.message = newMessage
        }
    }

    internal func yapDatabaseModified(notification: NSNotification) {
//        Logger.info("\(TAG) in \(#function)")
        AssertIsOnMainThread()

        let notifications = self.databaseConnection.beginLongLivedReadTransaction()

        guard self.databaseConnection.hasChange(forKey:message.uniqueId,
                                                 inCollection:TSInteraction.collection(),
                                                 in:notifications) else {
                                                    Logger.debug("\(TAG) No relevant changes.")
                                                    return
        }

        updateDBConnectionAndMessageToLatest()

        updateContent()
    }
}