bundesmessenger-ios/Riot/Modules/Room/DataSources/RoomDataSource.swift

// 
// Copyright 2022 New Vector Ltd
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

import Foundation

extension RoomDataSource {
    func sendAttributedTextMessage(_ attributedText: NSAttributedString,
                                   completion: @escaping (MXResponse<String?>) -> Void) {
        var localEcho: MXEvent?

        // TODO: emote
        let sanitized = sanitizedAttributedMessageText(attributedText)
        let rawText: String
        let html: String? = htmlMessageFromSanitizedAttributedText(sanitized)
        if #available(iOS 15.0, *) {
            rawText = StringPillsUtils.stringByReplacingPills(in: sanitized)
        } else {
            rawText = sanitized.string
        }

        room.sendTextMessage(rawText,
                             formattedText: html,
                             threadId: self.threadId,
                             localEcho: &localEcho,
                             completion: completion)

        if localEcho != nil {
            self.queueEvent(forProcessing: localEcho, with: self.roomState, direction: .forwards)
            self.processQueuedEvents(nil)
        }
    }

    func sendReply(to eventToReply: MXEvent,
                   withAttributedTextMessage attributedText: NSAttributedString,
                   completion: @escaping (MXResponse<String?>) -> Void) {
        var localEcho: MXEvent?

        let sanitized = sanitizedAttributedMessageText(attributedText)
        let rawText: String
        let html: String? = htmlMessageFromSanitizedAttributedText(sanitized)
        if #available(iOS 15.0, *) {
            rawText = StringPillsUtils.stringByReplacingPills(in: sanitized)
        } else {
            rawText = sanitized.string
        }

        let stringLocalizer: MXSendReplyEventStringLocalizerProtocol = MXKSendReplyEventStringLocalizer()

        room.sendReply(to: eventToReply,
                       textMessage: rawText,
                       formattedTextMessage: html,
                       stringLocalizer: stringLocalizer,
                       threadId: self.threadId,
                       localEcho: &localEcho,
                       completion: completion)

        if localEcho != nil {
            self.queueEvent(forProcessing: localEcho, with: self.roomState, direction: .forwards)
            self.processQueuedEvents(nil)
        }
    }

    func replaceAttributedTextMessage(for event: MXEvent,
                                      withAttributedTextMessage attributedText: NSAttributedString,
                                      success: @escaping ((String?) -> Void),
                                      failure: @escaping ((Error?) -> Void)) {
        let sanitized = sanitizedAttributedMessageText(attributedText)
        let rawText: String
        let html: String? = htmlMessageFromSanitizedAttributedText(sanitized)
        if #available(iOS 15.0, *) {
            rawText = StringPillsUtils.stringByReplacingPills(in: sanitized)
        } else {
            rawText = sanitized.string
        }

        let eventBody = event.content[kMXMessageBodyKey] as? String
        let eventFormattedBody = event.content["formatted_body"] as? String

        if rawText != eventBody && (eventFormattedBody == nil || html != eventFormattedBody) {
            self.mxSession.aggregations.replaceTextMessageEvent(
                event,
                withTextMessage: rawText,
                formattedText: html,
                localEcho: { localEcho in
                    // Apply the local echo to the timeline
                    self.updateEvent(withReplace: localEcho)

                    // Integrate the replace local event into the timeline like when sending a message
                    // This also allows to manage read receipt on this replace event
                    self.queueEvent(forProcessing: localEcho, with: self.roomState, direction: .forwards)
                    self.processQueuedEvents(nil)
                },
                success: success,
                failure: failure)
        } else {
            failure(nil)
        }
    }

    func sanitizedAttributedMessageText(_ attributedString: NSAttributedString) -> NSAttributedString {
        let newAttr = NSMutableAttributedString(attributedString: attributedString)
        newAttr.mutableString.replaceOccurrences(of: String(format: "%C", 0x00000000), with: "", range: .init(location: 0, length: newAttr.length))
        return newAttr
    }

    func htmlMessageFromSanitizedAttributedText(_ sanitizedText: NSAttributedString) -> String? {
        let rawText: String
        if #available(iOS 15.0, *) {
            rawText = StringPillsUtils.stringByReplacingPills(in: sanitizedText, asMarkdown: true)
        } else {
            rawText = sanitizedText.string
        }

        let html = eventFormatter.htmlString(fromMarkdownString: rawText)

        return html == sanitizedText.string ? nil : html
    }
}