path: root/src/plugins/Matrix.cpp

#include "../../plugins/Matrix.hpp"
#include "../../include/Storage.hpp"
#include "../../include/StringUtils.hpp"
#include "../../include/NetUtils.hpp"
#include <rapidjson/document.h>
#include <rapidjson/writer.h>
#include <rapidjson/stringbuffer.h>
#include <fcntl.h>
#include <unistd.h>

// TODO: Update avatar/display name when its changed in the room/globally.
// Send read receipt to server and receive notifications in /sync and show the notifications.
// Delete messages.
// Edit messages.
// Show images/videos inline.
// TODO: Verify if buffer of size 512 is enough for endpoints
// TODO: POST /_matrix/client/r0/rooms/{roomId}/read_markers after 5 seconds of receiving a message when the client is focused
// to mark messages as read
// When reaching top/bottom message, show older/newer messages.
// Remove older messages (outside screen) to save memory. Reload them when the selected body item is the top/bottom one.

// TODO: Verify if this class really is thread-safe (for example room data fields, user fields, message fields; etc that are updated in /sync)

static const char* SERVICE_NAME = "matrix";

static rapidjson::Value nullValue(rapidjson::kNullType);
static const rapidjson::Value& GetMember(const rapidjson::Value &obj, const char *key) {
    auto it = obj.FindMember(key);
    if(it != obj.MemberEnd())
        return it->value;
    return nullValue;
}

namespace QuickMedia {
    std::shared_ptr<UserInfo> RoomData::get_user_by_id(const std::string &user_id) {
        std::lock_guard<std::mutex> lock(room_mutex);
        auto user_it = user_info_by_user_id.find(user_id);
        if(user_it == user_info_by_user_id.end())
            return nullptr;
        return user_it->second;
    }

    void RoomData::add_user(std::shared_ptr<UserInfo> user) {
        std::lock_guard<std::mutex> lock(room_mutex);
        user_info_by_user_id.insert(std::make_pair(user->user_id, user));
    }

    void RoomData::set_user_read_marker(std::shared_ptr<UserInfo> &user, const std::string &event_id) {
        std::lock_guard<std::mutex> lock(user_mutex);
        user->read_marker_event_id = event_id;
    }

    std::string RoomData::get_user_read_marker(std::shared_ptr<UserInfo> &user) {
        std::lock_guard<std::mutex> lock(user_mutex);
        return user->read_marker_event_id;
    }

    void RoomData::prepend_messages_reverse(std::vector<std::shared_ptr<Message>> new_messages) {
        std::lock_guard<std::mutex> lock(room_mutex);
        for(auto it = new_messages.begin(); it != new_messages.end(); ++it) {
            if(message_by_event_id.find((*it)->event_id) == message_by_event_id.end()) {
                message_by_event_id.insert(std::make_pair((*it)->event_id, *it));
                messages.insert(messages.begin(), std::move(*it));
            }
        }
    }

    void RoomData::append_messages(std::vector<std::shared_ptr<Message>> new_messages) {
        std::lock_guard<std::mutex> lock(room_mutex);
        for(auto it = new_messages.begin(); it != new_messages.end(); ++it) {
            if(message_by_event_id.find((*it)->event_id) == message_by_event_id.end()) {
                message_by_event_id.insert(std::make_pair((*it)->event_id, *it));
                messages.push_back(std::move(*it));
            }
        }
    }

    std::shared_ptr<Message> RoomData::get_message_by_id(const std::string &id) {
        std::lock_guard<std::mutex> lock(room_mutex);
        auto message_it = message_by_event_id.find(id);
        if(message_it == message_by_event_id.end())
            return nullptr;
        return message_it->second;
    }

    std::vector<std::shared_ptr<UserInfo>> RoomData::get_users_excluding_me(const std::string &my_user_id) {
        std::lock_guard<std::mutex> lock(user_mutex);
        std::vector<std::shared_ptr<UserInfo>> users_excluding_me;
        for(auto &[user_id, user] : user_info_by_user_id) {
            if(user->user_id != my_user_id) {
                users_excluding_me.push_back(user);
            }
        }
        return users_excluding_me;
    }

    void RoomData::acquire_room_lock() {
        room_mutex.lock();
    }

    void RoomData::release_room_lock() {
        room_mutex.unlock();
    }

    const std::vector<std::shared_ptr<Message>>& RoomData::get_messages_thread_unsafe() const {
        return messages;
    }

    PluginResult Matrix::sync(RoomSyncMessages &room_messages) {
        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token },
            { "-m", "35" }
        };

        char url[512];
        if(next_batch.empty())
            snprintf(url, sizeof(url), "%s/_matrix/client/r0/sync?timeout=0", homeserver.c_str());
        else
            snprintf(url, sizeof(url), "%s/_matrix/client/r0/sync?timeout=30000&since=%s", homeserver.c_str(), next_batch.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        PluginResult result = sync_response_to_body_items(json_root, room_messages);
        if(result != PluginResult::OK)
            return result;

        const rapidjson::Value &next_batch_json = GetMember(json_root, "next_batch");
        if(next_batch_json.IsString()) {
            next_batch = next_batch_json.GetString();
            fprintf(stderr, "Matrix: next batch: %s\n", next_batch.c_str());
        } else {
            fprintf(stderr, "Matrix: missing next batch\n");
        }

        return PluginResult::OK;
    }

    void Matrix::get_room_join_updates(Rooms &new_rooms) {
        std::lock_guard<std::mutex> lock(room_data_mutex);
        new_rooms.insert(new_rooms.end(), rooms.begin() + room_list_read_index, rooms.end());
        size_t num_new_rooms = rooms.size() - room_list_read_index;
        room_list_read_index += num_new_rooms;
    }

    PluginResult Matrix::get_all_synced_room_messages(std::shared_ptr<RoomData> room, Messages &messages) {
        room->acquire_room_lock();
        messages = room->get_messages_thread_unsafe();
        room->release_room_lock();
        return PluginResult::OK;
    }

    PluginResult Matrix::get_previous_room_messages(std::shared_ptr<RoomData> room, Messages &messages) {
        room->acquire_room_lock();
        size_t num_messages_before = room->get_messages_thread_unsafe().size();
        room->release_room_lock();
        PluginResult result = get_previous_room_messages(room);
        if(result != PluginResult::OK)
            return result;

        room->acquire_room_lock();
        size_t num_messages_after = room->get_messages_thread_unsafe().size();
        size_t num_new_messages = num_messages_after - num_messages_before;
        messages.insert(messages.end(), room->get_messages_thread_unsafe().begin(), room->get_messages_thread_unsafe().begin() + num_new_messages);
        room->release_room_lock();
        return PluginResult::OK;
    }

    PluginResult Matrix::sync_response_to_body_items(const rapidjson::Document &root, RoomSyncMessages &room_messages) {
        if(!root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &rooms_json = GetMember(root, "rooms");
        if(!rooms_json.IsObject())
            return PluginResult::OK;

        const rapidjson::Value &join_json = GetMember(rooms_json, "join");
        if(!join_json.IsObject())
            return PluginResult::OK;

        for(auto const &it : join_json.GetObject()) {
            if(!it.value.IsObject())
                continue;

            const rapidjson::Value &room_id = it.name;
            if(!room_id.IsString())
                continue;

            std::string room_id_str = room_id.GetString();

            auto room = get_room_by_id(room_id_str);
            if(!room) {
                room = std::make_shared<RoomData>();
                room->id = room_id_str;
                add_room(room);
            }

            const rapidjson::Value &state_json = GetMember(it.value, "state");
            if(state_json.IsObject()) {
                const rapidjson::Value &events_json = GetMember(state_json, "events");
                events_add_user_info(events_json, room.get());
                events_set_room_name(events_json, room.get());
            }

            const rapidjson::Value &timeline_json = GetMember(it.value, "timeline");
            if(timeline_json.IsObject()) {
                if(room->prev_batch.empty()) {
                    // This may be non-existent if this is the first event in the room
                    const rapidjson::Value &prev_batch_json = GetMember(timeline_json, "prev_batch");
                    if(prev_batch_json.IsString())
                        room->prev_batch = prev_batch_json.GetString();
                }

                // TODO: Is there no better way to check for notifications? this is not robust...
                bool has_unread_notifications = false;
                const rapidjson::Value &unread_notification_json = GetMember(it.value, "unread_notifications");
                if(unread_notification_json.IsObject()) {
                    const rapidjson::Value &highlight_count_json = GetMember(unread_notification_json, "highlight_count");
                    if(highlight_count_json.IsNumber() && highlight_count_json.GetInt64() > 0)
                        has_unread_notifications = true;
                }

                const rapidjson::Value &events_json = GetMember(timeline_json, "events");
                events_add_user_info(events_json, room.get());
                events_add_messages(events_json, room, MessageDirection::AFTER, &room_messages, has_unread_notifications);
                events_set_room_name(events_json, room.get());
            }

            const rapidjson::Value &ephemeral_json = GetMember(it.value, "ephemeral");
            if(ephemeral_json.IsObject()) {
                const rapidjson::Value &events_json = GetMember(ephemeral_json, "events");
                events_add_user_read_markers(events_json, room.get());
            }
        }

        return PluginResult::OK;
    }

    static sf::Color user_id_to_color(const std::string &user_id) {
        uint32_t color = 2166136261;
        for(unsigned char c : user_id) {
            color = (color * 16777619) ^ c;
        }
        sf::Uint8 *col = (sf::Uint8*)&color;
        sf::Color result(col[0], col[1], col[2]);
        result.r = std::min(255, 80 + (int)result.r);
        result.g = std::min(255, 80 + (int)result.g);
        result.b = std::min(255, 80 + (int)result.b);
        result.a = 255;
        return result;
    }

    void Matrix::events_add_user_info(const rapidjson::Value &events_json, RoomData *room_data) {
        if(!events_json.IsArray())
            return;

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            if(!event_item_json.IsObject())
                continue;

            const rapidjson::Value &type_json = GetMember(event_item_json, "type");
            if(!type_json.IsString() || strcmp(type_json.GetString(), "m.room.member") != 0)
                continue;

            const rapidjson::Value &sender_json = GetMember(event_item_json, "sender");
            if(!sender_json.IsString())
                continue;
            
            const rapidjson::Value &content_json = GetMember(event_item_json, "content");
            if(!content_json.IsObject())
                continue;

            const rapidjson::Value &membership_json = GetMember(content_json, "membership");
            if(!membership_json.IsString() || strcmp(membership_json.GetString(), "join") != 0)
                continue;

            std::string avatar_url_str;
            const rapidjson::Value &avatar_url_json = GetMember(content_json, "avatar_url");
            if(avatar_url_json.IsString())
                avatar_url_str = avatar_url_json.GetString();

            const rapidjson::Value &display_name_json = GetMember(content_json, "displayname");

            std::string sender_json_str = sender_json.GetString();

            auto user_info = std::make_shared<UserInfo>();
            user_info->user_id = sender_json_str;
            user_info->avatar_url = std::move(avatar_url_str);
            if(strncmp(user_info->avatar_url.c_str(), "mxc://", 6) == 0)
                user_info->avatar_url.erase(user_info->avatar_url.begin(), user_info->avatar_url.begin() + 6);
            if(!user_info->avatar_url.empty())
                user_info->avatar_url = homeserver + "/_matrix/media/r0/thumbnail/" + user_info->avatar_url + "?width=32&height=32&method=crop";
            user_info->display_name = display_name_json.IsString() ? display_name_json.GetString() : sender_json_str;
            user_info->display_name_color = user_id_to_color(sender_json_str);
            
            // Overwrites user data
            room_data->add_user(std::move(user_info));
        }
    }

    void Matrix::events_add_user_read_markers(const rapidjson::Value &events_json, RoomData *room_data) {
        if(!events_json.IsArray())
            return;

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            if(!event_item_json.IsObject())
                continue;

            const rapidjson::Value &type_json = GetMember(event_item_json, "type");
            if(!type_json.IsString() || strcmp(type_json.GetString(), "m.receipt") != 0)
                continue;
            
            const rapidjson::Value &content_json = GetMember(event_item_json, "content");
            if(!content_json.IsObject())
                continue;

            for(auto const &it2 : content_json.GetObject()) {
                if(!it2.value.IsObject())
                    continue;

                const rapidjson::Value &event_id_json = it2.name;
                if(!event_id_json.IsString())
                    continue;

                const rapidjson::Value &read_json = GetMember(it2.value, "m.read");
                if(!read_json.IsObject())
                    continue;

                std::string event_id_str = event_id_json.GetString();

                for(auto const &it3 : read_json.GetObject()) {
                    if(!it3.value.IsObject())
                        continue;

                    const rapidjson::Value &user_id_json = it3.name;
                    if(!user_id_json.IsString())
                        continue;

                    auto user = room_data->get_user_by_id(user_id_json.GetString());
                    if(!user) {
                        fprintf(stderr, "Receipt read receipt for unknown user: %s, ignoring...\n", user_id_json.GetString());
                        continue;
                    }

                    room_data->set_user_read_marker(user, event_id_str);
                }
            }
        }
    }

    static std::string message_content_extract_thumbnail_url(const rapidjson::Value &content_json, const std::string &homeserver) {
        const rapidjson::Value &info_json = GetMember(content_json, "info");
        if(info_json.IsObject()) {
            const rapidjson::Value &thumbnail_url_json = GetMember(info_json, "thumbnail_url");
            if(thumbnail_url_json.IsString()) {
                std::string thumbnail_str = thumbnail_url_json.GetString();
                if(strncmp(thumbnail_str.c_str(), "mxc://", 6) == 0) {
                    thumbnail_str.erase(thumbnail_str.begin(), thumbnail_str.begin() + 6);
                    return homeserver + "/_matrix/media/r0/download/" + std::move(thumbnail_str);
                }
            }
        }
        return "";
    }

    static bool message_content_extract_thumbnail_size(const rapidjson::Value &content_json, sf::Vector2i &thumbnail_size) {
        const rapidjson::Value &info_json = GetMember(content_json, "info");
        if(!info_json.IsObject())
            return false;

        bool found_resolution = false;
        const rapidjson::Value &w_json = GetMember(info_json, "w");
        const rapidjson::Value &h_json = GetMember(info_json, "h");
        if(w_json.IsNumber() && h_json.IsNumber()) {
            thumbnail_size.x = w_json.GetInt();
            thumbnail_size.y = h_json.GetInt();
            found_resolution = true;
        }

        const rapidjson::Value &thumbnail_info_json = GetMember(info_json, "thumbnail_info");
        if(thumbnail_info_json.IsObject()) {
            const rapidjson::Value &w_json = GetMember(thumbnail_info_json, "w");
            const rapidjson::Value &h_json = GetMember(thumbnail_info_json, "h");
            if(w_json.IsNumber() && h_json.IsNumber()) {
                thumbnail_size.x = w_json.GetInt();
                thumbnail_size.y = h_json.GetInt();
                found_resolution = true;
            }
        }

        return found_resolution;
    }

    // TODO: Is this really the proper way to check for username mentions?
    static bool is_username_seperating_character(char c) {
        switch(c) {
            case ' ':
            case '\n':
            case '\t':
            case '\v':
            case '.':
            case ',':
            case '@':
            case ':':
            case '?':
            case '!':
            case '<':
            case '>':
            case '\0':
                return true;
            default:
                return false;
        }
        return false;
    }

    // TODO: Do not show notification if mention is a reply to somebody else that replies to me? also dont show notification everytime a mention is edited
    bool message_contains_user_mention(const std::string &msg, const std::string &username) {
        if(msg.empty())
            return false;

        size_t index = 0;
        while(index < msg.size()) {
            size_t found_index = msg.find(username, index);
            if(found_index == std::string::npos)
                return false;

            char prev_char = ' ';
            if(found_index > 0)
                prev_char = msg[found_index - 1];

            char next_char = '\0';
            if(found_index + username.size() < msg.size() - 1)
                next_char = msg[found_index + username.size()];

            if(is_username_seperating_character(prev_char) && is_username_seperating_character(next_char))
                return true;

            index += username.size();
        }

        return false;
    }

    void Matrix::events_add_messages(const rapidjson::Value &events_json, std::shared_ptr<RoomData> &room_data, MessageDirection message_dir, RoomSyncMessages *room_messages, bool has_unread_notifications) {
        if(!events_json.IsArray())
            return;

        std::vector<std::shared_ptr<Message>> new_messages;
        auto me = get_me(room_data);

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            std::shared_ptr<Message> new_message = parse_message_event(event_item_json, room_data.get());
            if(!new_message)
                continue;

            // TODO: Is @room ok? shouldn't we also check if the user has permission to do @room? (only when notifications are limited to @mentions)
            if(has_unread_notifications && me)
                new_message->mentions_me = message_contains_user_mention(new_message->body, me->display_name) || message_contains_user_mention(new_message->body, "@room");

            new_messages.push_back(std::move(new_message));
        }

        // TODO: Add directly to this instead when set? otherwise add to new_messages
        if(room_messages)
            (*room_messages)[room_data] = new_messages;

        // TODO: Loop and std::move instead? doesn't insert create copies?
        if(message_dir == MessageDirection::BEFORE) {
            room_data->prepend_messages_reverse(std::move(new_messages));
        } else if(message_dir == MessageDirection::AFTER) {
            room_data->append_messages(std::move(new_messages));
        }
    }

    std::shared_ptr<Message> Matrix::parse_message_event(const rapidjson::Value &event_item_json, RoomData *room_data) {
        if(!event_item_json.IsObject())
            return nullptr;

        const rapidjson::Value &sender_json = GetMember(event_item_json, "sender");
        if(!sender_json.IsString())
            return nullptr;

        std::string sender_json_str = sender_json.GetString();

        const rapidjson::Value &event_id_json = GetMember(event_item_json, "event_id");
        if(!event_id_json.IsString())
            return nullptr;

        std::string event_id_str = event_id_json.GetString();
        
        const rapidjson::Value *content_json = &GetMember(event_item_json, "content");
        if(!content_json->IsObject())
            return nullptr;

        auto user = room_data->get_user_by_id(sender_json_str);
        if(!user) {
            // Note: this is important because otherwise replying and such is broken
            fprintf(stderr, "Warning: skipping unknown user: %s\n", sender_json_str.c_str());
            return nullptr;
        }

        time_t timestamp = 0;
        const rapidjson::Value &origin_server_ts = GetMember(event_item_json, "origin_server_ts");
        if(origin_server_ts.IsNumber())
            timestamp = origin_server_ts.GetInt64();

        const rapidjson::Value &type_json = GetMember(event_item_json, "type");
        if(!type_json.IsString())
            return nullptr;

        RelatedEventType related_event_type = RelatedEventType::NONE;
        std::string related_event_id;
        const rapidjson::Value &relates_to_json = GetMember(*content_json, "m.relates_to");
        if(relates_to_json.IsObject()) {
            const rapidjson::Value &replaces_event_id_json = GetMember(relates_to_json, "event_id");
            const rapidjson::Value &rel_type_json = GetMember(relates_to_json, "rel_type");
            if(replaces_event_id_json.IsString() && rel_type_json.IsString() && strcmp(rel_type_json.GetString(), "m.replace") == 0) {
                related_event_id = replaces_event_id_json.GetString();
                related_event_type = RelatedEventType::EDIT;
            } else {
                const rapidjson::Value &in_reply_to_json = GetMember(relates_to_json, "m.in_reply_to");
                if(in_reply_to_json.IsObject()) {
                    const rapidjson::Value &in_reply_to_event_id = GetMember(in_reply_to_json, "event_id");
                    if(in_reply_to_event_id.IsString()) {
                        related_event_id = in_reply_to_event_id.GetString();
                        related_event_type = RelatedEventType::REPLY;
                    }
                }
            }
        }

        const rapidjson::Value &new_content_json = GetMember(*content_json, "m.new_content");
        if(new_content_json.IsObject())
            content_json = &new_content_json;

        const rapidjson::Value &content_type = GetMember(*content_json, "msgtype");
        if(!content_type.IsString() || strcmp(type_json.GetString(), "m.room.redaction") == 0) {
            auto message = std::make_shared<Message>();
            message->type = MessageType::REDACTION;
            message->user = user;
            message->event_id = event_id_str;
            message->body = "Message deleted";
            message->timestamp = timestamp;
            message->related_event_type = RelatedEventType::REDACTION;

            const rapidjson::Value &reason_json = GetMember(*content_json, "reason");
            if(reason_json.IsString()) {
                message->body += ", reason: "; 
                message->body += reason_json.GetString();
            }

            const rapidjson::Value &redacts_json = GetMember(event_item_json, "redacts");
            if(redacts_json.IsString())
                message->related_event_id = redacts_json.GetString();

            return message;
        }

        if(strcmp(type_json.GetString(), "m.room.message") != 0)
            return nullptr;

        const rapidjson::Value &body_json = GetMember(*content_json, "body");
        if(!body_json.IsString())
            return nullptr;

        auto message = std::make_shared<Message>();
        std::string prefix;

        // TODO: Also show joins, leave, invites, bans, kicks, mutes, etc

        if(strcmp(content_type.GetString(), "m.text") == 0) {
            message->type = MessageType::TEXT;
        } else if(strcmp(content_type.GetString(), "m.image") == 0) {
            const rapidjson::Value &url_json = GetMember(*content_json, "url");
            if(!url_json.IsString() || strncmp(url_json.GetString(), "mxc://", 6) != 0)
                return nullptr;

            message->url = homeserver + "/_matrix/media/r0/download/" + (url_json.GetString() + 6);
            message->thumbnail_url = message_content_extract_thumbnail_url(*content_json, homeserver);
            message_content_extract_thumbnail_size(*content_json, message->thumbnail_size);
            message->type = MessageType::IMAGE;
        } else if(strcmp(content_type.GetString(), "m.video") == 0) {
            const rapidjson::Value &url_json = GetMember(*content_json, "url");
            if(!url_json.IsString() || strncmp(url_json.GetString(), "mxc://", 6) != 0)
                return nullptr;

            message->url = homeserver + "/_matrix/media/r0/download/" + (url_json.GetString() + 6);
            message->thumbnail_url = message_content_extract_thumbnail_url(*content_json, homeserver);
            message_content_extract_thumbnail_size(*content_json, message->thumbnail_size);
            message->type = MessageType::VIDEO;
        } else if(strcmp(content_type.GetString(), "m.audio") == 0) {
            const rapidjson::Value &url_json = GetMember(*content_json, "url");
            if(!url_json.IsString() || strncmp(url_json.GetString(), "mxc://", 6) != 0)
                return nullptr;

            message->url = homeserver + "/_matrix/media/r0/download/" + (url_json.GetString() + 6);
            message->type = MessageType::AUDIO;
        } else if(strcmp(content_type.GetString(), "m.file") == 0) {
            const rapidjson::Value &url_json = GetMember(*content_json, "url");
            if(!url_json.IsString() || strncmp(url_json.GetString(), "mxc://", 6) != 0)
                return nullptr;

            message->url = homeserver + "/_matrix/media/r0/download/" + (url_json.GetString() + 6);
            message->type = MessageType::FILE;
        } else if(strcmp(content_type.GetString(), "m.emote") == 0) { // this is a /me message, TODO: show /me messages differently
            message->type = MessageType::TEXT;
            prefix = "*" + user->display_name + "* ";
        } else if(strcmp(content_type.GetString(), "m.notice") == 0) { // TODO: show notices differently
            message->type = MessageType::TEXT;
            prefix = "* NOTICE * ";
        } else if(strcmp(content_type.GetString(), "m.location") == 0) { // TODO: show locations differently
            const rapidjson::Value &geo_uri_json = GetMember(*content_json, "geo_uri");
            if(geo_uri_json.IsString())
                prefix = geo_uri_json.GetString() + std::string(" | ");

            message->type = MessageType::TEXT;
            message->thumbnail_url = message_content_extract_thumbnail_url(*content_json, homeserver);
            message_content_extract_thumbnail_size(*content_json, message->thumbnail_size);
        } else {
            return nullptr;
        }

        message->user = user;
        message->event_id = event_id_str;
        message->body = prefix + body_json.GetString();
        message->related_event_id = std::move(related_event_id);
        message->related_event_type = related_event_type;
        message->timestamp = timestamp;
        return message;
    }

    // Returns empty string on error
    static std::string extract_user_name_from_user_id(const std::string &user_id) {
        size_t index = user_id.find(':');
        if(index == std::string::npos || index == 0 || user_id.empty() || user_id[0] != '@')
            return "";
        return user_id.substr(1, index - 1);
    }

    static std::string combine_user_display_names_for_room_name(const std::vector<std::shared_ptr<UserInfo>> &user_info, const std::string &fallback_user_id) {
        std::string result;
        if(user_info.size() == 0)
            result = extract_user_name_from_user_id(fallback_user_id);
        else if(user_info.size() == 1)
            result = user_info[0]->display_name;
        else if(user_info.size() == 2)
            result = user_info[0]->display_name + " and " + user_info[1]->display_name;
        else if(user_info.size() > 2)
            result = user_info[0]->display_name + ", " + user_info[1]->display_name + " and " + std::to_string(user_info.size() - 2) + " other(s)";
        return result;
    }

    void Matrix::events_set_room_name(const rapidjson::Value &events_json, RoomData *room_data) {
        if(!events_json.IsArray())
            return;

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            if(!event_item_json.IsObject())
                continue;

            const rapidjson::Value &type_json = GetMember(event_item_json, "type");
            if(!type_json.IsString() || strcmp(type_json.GetString(), "m.room.name") != 0)
                continue;
            
            const rapidjson::Value &content_json = GetMember(event_item_json, "content");
            if(!content_json.IsObject())
                continue;

            const rapidjson::Value &name_json = GetMember(content_json, "name");
            if(!name_json.IsString())
                continue;

            room_data->name = name_json.GetString();
        }

        std::vector<std::shared_ptr<UserInfo>> users_excluding_me;
        if(room_data->name.empty() || room_data->avatar_url.empty())
            users_excluding_me = room_data->get_users_excluding_me(user_id); // TODO: What about thread safety with user_id? its reset in /logout

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            if(!event_item_json.IsObject())
                continue;

            const rapidjson::Value &type_json = GetMember(event_item_json, "type");
            if(!type_json.IsString() || strcmp(type_json.GetString(), "m.room.create") != 0)
                continue;
            
            const rapidjson::Value &content_json = GetMember(event_item_json, "content");
            if(!content_json.IsObject())
                continue;

            const rapidjson::Value &creator_json = GetMember(content_json, "creator");
            if(!creator_json.IsString())
                continue;

            if(room_data->name.empty())
                room_data->name = combine_user_display_names_for_room_name(users_excluding_me, creator_json.GetString());

            if(room_data->avatar_url.empty()) {
                if(users_excluding_me.empty()) {
                    auto user = room_data->get_user_by_id(creator_json.GetString());
                    if(user)
                        room_data->avatar_url = user->avatar_url;
                } else {
                    // TODO: If there are multiple users, then we want to use some other type of avatar, not the first users avatar
                    room_data->avatar_url = users_excluding_me.front()->avatar_url;
                }
            }
        }

        for(const rapidjson::Value &event_item_json : events_json.GetArray()) {
            if(!event_item_json.IsObject())
                continue;

            const rapidjson::Value &type_json = GetMember(event_item_json, "type");
            if(!type_json.IsString() || strcmp(type_json.GetString(), "m.room.avatar") != 0)
                continue;
            
            const rapidjson::Value &content_json = GetMember(event_item_json, "content");
            if(!content_json.IsObject())
                continue;

            const rapidjson::Value &url_json = GetMember(content_json, "url");
            if(!url_json.IsString() || strncmp(url_json.GetString(), "mxc://", 6) != 0)
                continue;

            std::string url_json_str = url_json.GetString() + 6;
            room_data->avatar_url = homeserver + "/_matrix/media/r0/thumbnail/" + std::move(url_json_str) + "?width=32&height=32&method=crop";
        }
    }

    PluginResult Matrix::get_previous_room_messages(std::shared_ptr<RoomData> &room_data) {
        std::string from = room_data->prev_batch;
        if(from.empty()) {
            fprintf(stderr, "Info: missing previous batch for room: %s, using /sync next batch\n", room_data->id.c_str());
            from = next_batch;
            if(from.empty()) {
                fprintf(stderr, "Error: missing next batch!\n");
                return PluginResult::OK;
            }
        }

        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("lazy_load_members", true, request_data.GetAllocator());

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string filter = url_param_encode(buffer.GetString());

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/client/r0/rooms/%s/messages?from=%s&limit=20&dir=b&filter=%s", homeserver.c_str(), room_data->id.c_str(), from.c_str(), filter.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &state_json = GetMember(json_root, "state");
        events_add_user_info(state_json, room_data.get());
        events_set_room_name(state_json, room_data.get());

        const rapidjson::Value &chunk_json = GetMember(json_root, "chunk");
        events_add_messages(chunk_json, room_data, MessageDirection::BEFORE, nullptr, false);

        const rapidjson::Value &end_json = GetMember(json_root, "end");
        if(!end_json.IsString()) {
            fprintf(stderr, "Warning: matrix messages response is missing 'end', this could happen if we received the very first messages in the room\n");
            return PluginResult::OK;
        }

        room_data->prev_batch = end_json.GetString();
        return PluginResult::OK;
    }

    static bool generate_random_characters(char *buffer, int buffer_size) {
        int fd = open("/dev/urandom", O_RDONLY);
        if(fd == -1) {
            perror("/dev/urandom");
            return false;
        }

        if(read(fd, buffer, buffer_size) < buffer_size) {
            fprintf(stderr, "Failed to read %d bytes from /dev/urandom\n", buffer_size);
            close(fd);
            return false;
        }

        close(fd);
        return true;
    }

    static std::string random_characters_to_readable_string(const char *buffer, int buffer_size) {
        std::ostringstream result;
        result << std::hex;
        for(int i = 0; i < buffer_size; ++i)
            result << (int)(unsigned char)buffer[i];
        return result.str();
    }

    static const char* content_type_to_message_type(ContentType content_type) {
        if(is_content_type_video(content_type))
            return "m.video";
        else if(is_content_type_audio(content_type))
            return "m.audio";
        else if(is_content_type_image(content_type))
            return "m.image";
        else
            return "m.file";
    }

    PluginResult Matrix::post_message(std::shared_ptr<RoomData> room, const std::string &body, const std::optional<UploadInfo> &file_info, const std::optional<UploadInfo> &thumbnail_info) {
        char random_characters[18];
        if(!generate_random_characters(random_characters, sizeof(random_characters)))
            return PluginResult::ERR;

        std::string random_readable_chars = random_characters_to_readable_string(random_characters, sizeof(random_characters));

        std::string formatted_body;
        bool contains_formatted_text = false;
        if(!file_info) {
            int line = 0;
            string_split(body, '\n', [&formatted_body, &contains_formatted_text, &line](const char *str, size_t size){
                if(line > 0)
                    formatted_body += "<br/>";
                std::string line_str(str, size);
                html_escape_sequences(line_str);
                if(size > 0 && str[0] == '>') {
                    formatted_body += "<font color=\"#789922\">";
                    formatted_body += line_str;
                    formatted_body += "</font>";
                    contains_formatted_text = true;
                } else {
                    formatted_body += line_str;
                }
                ++line;
                return true;
            });
        }

        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("msgtype", rapidjson::StringRef(file_info ? content_type_to_message_type(file_info->content_type) : "m.text"), request_data.GetAllocator());
        request_data.AddMember("body", rapidjson::StringRef(body.c_str()), request_data.GetAllocator());
        if(contains_formatted_text) {
            request_data.AddMember("format", "org.matrix.custom.html", request_data.GetAllocator());
            request_data.AddMember("formatted_body", rapidjson::StringRef(formatted_body.c_str()), request_data.GetAllocator());
        }

        // TODO: Add hashblur?
        if(file_info) {
            rapidjson::Value info_json(rapidjson::kObjectType);
            info_json.AddMember("size", file_info->file_size, request_data.GetAllocator());
            info_json.AddMember("mimetype", rapidjson::StringRef(content_type_to_string(file_info->content_type)), request_data.GetAllocator());
            if(file_info->dimensions) {
                info_json.AddMember("w", file_info->dimensions->width, request_data.GetAllocator());
                info_json.AddMember("h", file_info->dimensions->height, request_data.GetAllocator());
            }
            if(file_info->duration_seconds) {
                // TODO: Check for overflow?
                info_json.AddMember("duration", (int)(file_info->duration_seconds.value() * 1000.0), request_data.GetAllocator());
            }

            if(thumbnail_info) {
                rapidjson::Value thumbnail_info_json(rapidjson::kObjectType);
                thumbnail_info_json.AddMember("size", thumbnail_info->file_size, request_data.GetAllocator());
                thumbnail_info_json.AddMember("mimetype", rapidjson::StringRef(content_type_to_string(thumbnail_info->content_type)), request_data.GetAllocator());
                if(thumbnail_info->dimensions) {
                    thumbnail_info_json.AddMember("w", thumbnail_info->dimensions->width, request_data.GetAllocator());
                    thumbnail_info_json.AddMember("h", thumbnail_info->dimensions->height, request_data.GetAllocator());
                }

                info_json.AddMember("thumbnail_url", rapidjson::StringRef(thumbnail_info->content_uri.c_str()), request_data.GetAllocator());
                info_json.AddMember("info", std::move(thumbnail_info_json), request_data.GetAllocator());
            }

            request_data.AddMember("info", std::move(info_json), request_data.GetAllocator());
            request_data.AddMember("url", rapidjson::StringRef(file_info->content_uri.c_str()), request_data.GetAllocator());
        }

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", buffer.GetString() }
        };

        char request_url[512];
        snprintf(request_url, sizeof(request_url), "%s/_matrix/client/r0/rooms/%s/send/m.room.message/m%ld.%.*s", homeserver.c_str(), room->id.c_str(), time(NULL), (int)random_readable_chars.size(), random_readable_chars.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, request_url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &event_id_json = GetMember(json_root, "event_id");
        if(!event_id_json.IsString())
            return PluginResult::ERR;

        fprintf(stderr, "Matrix post message, response event id: %s\n", event_id_json.GetString());
        return PluginResult::OK;
    }

    static std::string remove_reply_formatting(const std::string &str) {
        if(strncmp(str.c_str(), "> <@", 4) == 0) {
            size_t index = str.find("> ", 4);
            if(index != std::string::npos) {
                size_t msg_begin = str.find("\n\n", index + 2);
                if(msg_begin != std::string::npos)
                    return str.substr(msg_begin + 2);
            }
        }
        return str;
    }

    static std::string block_quote(const std::string &str) {
        std::string result;
        for(char c : str) {
            if(c == '>') {
                result += "\\>";
            } else if(c == '\n') {
                result += "\n> ";
            } else {
                result += c;
            }
        }
        return result;
    }

    static std::string get_reply_message(const Message *message) {
        std::string related_to_body;
        switch(message->type) {
            case MessageType::TEXT: {
                if(message->related_event_type != RelatedEventType::NONE)
                    related_to_body = remove_reply_formatting(message->body);
                else
                    related_to_body = message->body;
                break;
            }
            case MessageType::IMAGE:
                related_to_body = "sent an image";
                break;
            case MessageType::VIDEO:
                related_to_body = "sent a video";
                break;
            case MessageType::AUDIO:
                related_to_body = "sent an audio file";
                break;
            case MessageType::FILE:
                related_to_body = "sent a file";
                break;
            case MessageType::REDACTION:
                related_to_body = message->body;
                break;
        }
        return related_to_body;
    }

    static std::string create_body_for_message_reply(const Message *message, const std::string &body) {
        return "> <" + message->user->user_id + "> " + block_quote(get_reply_message(message)) + "\n\n" + body;
    }

    static std::string create_formatted_body_for_message_reply(const Message *message, const std::string &body) {
        std::string formatted_body = body;
        std::string related_to_body = get_reply_message(message);
        html_escape_sequences(formatted_body);
        html_escape_sequences(related_to_body);
        // TODO: Fix invalid.url, etc to use same as element. This is required to navigate to reply message in element mobile.
        // TODO: Add keybind to navigate to the reply message, which would also depend on this formatting.
        return "<mx-reply>"
                   "<blockquote>"
                       "<a href=\"https://invalid.url\">In reply to</a>"
                       "<a href=\"https://matrix.to/#/" + message->user->user_id + "\">" + message->user->user_id + "</a><br>" + std::move(related_to_body) +
                   "</blockquote>"
                "</mx-reply>" + std::move(formatted_body);
    }

    // TODO: Support greentext
    PluginResult Matrix::post_reply(std::shared_ptr<RoomData> room, const std::string &body, void *relates_to) {
        // TODO: Store shared_ptr<Message> instead of raw pointer...
        Message *relates_to_message_raw = (Message*)relates_to;
        std::shared_ptr<Message> relates_to_message_shared = room->get_message_by_id(relates_to_message_raw->event_id);
        std::shared_ptr<Message> relates_to_message_original = get_edited_message_original_message(room.get(), relates_to_message_shared);
        if(!relates_to_message_original) {
            fprintf(stderr, "Failed to get the original message for message with event id: %s\n", relates_to_message_raw->event_id.c_str());
            return PluginResult::ERR;
        }

        char random_characters[18];
        if(!generate_random_characters(random_characters, sizeof(random_characters)))
            return PluginResult::ERR;

        std::string random_readable_chars = random_characters_to_readable_string(random_characters, sizeof(random_characters));

        rapidjson::Document in_reply_to_json(rapidjson::kObjectType);
        in_reply_to_json.AddMember("event_id", rapidjson::StringRef(relates_to_message_original->event_id.c_str()), in_reply_to_json.GetAllocator());

        rapidjson::Document relates_to_json(rapidjson::kObjectType);
        relates_to_json.AddMember("m.in_reply_to", std::move(in_reply_to_json), relates_to_json.GetAllocator());

        std::string message_reply_body = create_body_for_message_reply(relates_to_message_raw, body); // Yes, the reply is to the edited message but the event_id reference is to the original message...
        std::string formatted_message_reply_body = create_formatted_body_for_message_reply(relates_to_message_raw, body);

        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("msgtype", "m.text", request_data.GetAllocator()); // TODO: Allow image reply? element doesn't do that but we could!
        request_data.AddMember("body", rapidjson::StringRef(message_reply_body.c_str()), request_data.GetAllocator());
        request_data.AddMember("format", "org.matrix.custom.html", request_data.GetAllocator());
        request_data.AddMember("formatted_body", rapidjson::StringRef(formatted_message_reply_body.c_str()), request_data.GetAllocator());
        request_data.AddMember("m.relates_to", std::move(relates_to_json), request_data.GetAllocator());

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", buffer.GetString() }
        };

        char request_url[512];
        snprintf(request_url, sizeof(request_url), "%s/_matrix/client/r0/rooms/%s/send/m.room.message/m%ld.%.*s", homeserver.c_str(), room->id.c_str(), time(NULL), (int)random_readable_chars.size(), random_readable_chars.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, request_url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &event_id_json = GetMember(json_root, "event_id");
        if(!event_id_json.IsString())
            return PluginResult::ERR;

        fprintf(stderr, "Matrix post reply, response event id: %s\n", event_id_json.GetString());
        return PluginResult::OK;
    }

    PluginResult Matrix::post_edit(std::shared_ptr<RoomData> room, const std::string &body, void *relates_to) {
        Message *relates_to_message_raw = (Message*)relates_to;
        std::shared_ptr<Message> relates_to_message_shared = room->get_message_by_id(relates_to_message_raw->event_id);
        std::shared_ptr<Message> relates_to_message_original = get_edited_message_original_message(room.get(), relates_to_message_shared);
        if(!relates_to_message_original) {
            fprintf(stderr, "Failed to get the original message for message with event id: %s\n", relates_to_message_raw->event_id.c_str());
            return PluginResult::ERR;
        }

        char random_characters[18];
        if(!generate_random_characters(random_characters, sizeof(random_characters)))
            return PluginResult::ERR;

        std::string random_readable_chars = random_characters_to_readable_string(random_characters, sizeof(random_characters));

        std::string formatted_body;
        bool contains_formatted_text = false;
        int line = 0;
        string_split(body, '\n', [&formatted_body, &contains_formatted_text, &line](const char *str, size_t size){
            if(line > 0)
                formatted_body += "<br/>";
            if(size > 0 && str[0] == '>') {
                std::string line(str, size);
                html_escape_sequences(line);
                formatted_body += "<font color=\"#789922\">";
                formatted_body += line;
                formatted_body += "</font>";
                contains_formatted_text = true;
            } else {
                formatted_body.append(str, size);
            }
            ++line;
            return true;
        });

        rapidjson::Document new_content_json(rapidjson::kObjectType);
        new_content_json.AddMember("msgtype", "m.text", new_content_json.GetAllocator());
        new_content_json.AddMember("body", rapidjson::StringRef(body.c_str()), new_content_json.GetAllocator());
        if(contains_formatted_text) {
            new_content_json.AddMember("format", "org.matrix.custom.html", new_content_json.GetAllocator());
            new_content_json.AddMember("formatted_body", rapidjson::StringRef(formatted_body.c_str()), new_content_json.GetAllocator());
        }

        rapidjson::Document relates_to_json(rapidjson::kObjectType);
        relates_to_json.AddMember("event_id", rapidjson::StringRef(relates_to_message_original->event_id.c_str()), relates_to_json.GetAllocator());
        relates_to_json.AddMember("rel_type", "m.replace", relates_to_json.GetAllocator());

        std::string body_edit_str = " * " + body;
        std::string formatted_body_edit_str;

        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("msgtype", "m.text", request_data.GetAllocator()); // TODO: Allow other types of edits
        request_data.AddMember("body", rapidjson::StringRef(body_edit_str.c_str()), request_data.GetAllocator());
        if(contains_formatted_text) {
            formatted_body_edit_str = " * " + formatted_body;
            request_data.AddMember("format", "org.matrix.custom.html", request_data.GetAllocator());
            request_data.AddMember("formatted_body", rapidjson::StringRef(formatted_body_edit_str.c_str()), request_data.GetAllocator());
        }
        request_data.AddMember("m.new_content", std::move(new_content_json), request_data.GetAllocator());
        request_data.AddMember("m.relates_to", std::move(relates_to_json), request_data.GetAllocator());

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", buffer.GetString() }
        };

        char request_url[512];
        snprintf(request_url, sizeof(request_url), "%s/_matrix/client/r0/rooms/%s/send/m.room.message/m%ld.%.*s", homeserver.c_str(), room->id.c_str(), time(NULL), (int)random_readable_chars.size(), random_readable_chars.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, request_url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &event_id_json = GetMember(json_root, "event_id");
        if(!event_id_json.IsString())
            return PluginResult::ERR;

        fprintf(stderr, "Matrix post edit, response event id: %s\n", event_id_json.GetString());
        return PluginResult::OK;
    }

    // TODO: Right now this recursively calls /rooms/<room_id>/context/<event_id> and trusts server to not make it recursive. To make this robust, check iteration count and do not trust server.
    // TODO: Optimize?
    std::shared_ptr<Message> Matrix::get_edited_message_original_message(RoomData *room_data, std::shared_ptr<Message> message) {
        if(!message || message->related_event_type != RelatedEventType::EDIT)
            return message;
        return get_edited_message_original_message(room_data, get_message_by_id(room_data, message->related_event_id));
    }

    std::shared_ptr<Message> Matrix::get_message_by_id(RoomData *room, const std::string &event_id) {
        std::shared_ptr<Message> existing_room_message = room->get_message_by_id(event_id);
        if(existing_room_message)
            return existing_room_message;

        auto fetched_message_it = room->fetched_messages_by_event_id.find(event_id);
        if(fetched_message_it != room->fetched_messages_by_event_id.end())
            return fetched_message_it->second;
        
        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("lazy_load_members", true, request_data.GetAllocator());

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string filter = url_param_encode(buffer.GetString());

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/client/r0/rooms/%s/context/%s?limit=0&filter=%s", homeserver.c_str(), room->id.c_str(), event_id.c_str(), filter.c_str());

        std::string err_msg;
        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true, &err_msg);
        if(download_result != DownloadResult::OK) return nullptr;

        if(json_root.IsObject()) {
            const rapidjson::Value &error_json = GetMember(json_root, "error");
            if(error_json.IsString()) {
                fprintf(stderr, "Matrix::get_message_by_id, error: %s\n", error_json.GetString());
                room->fetched_messages_by_event_id.insert(std::make_pair(event_id, nullptr));
                return nullptr;
            }
        }

        const rapidjson::Value &event_json = GetMember(json_root, "event");
        std::shared_ptr<Message> new_message = parse_message_event(event_json, room);
        room->fetched_messages_by_event_id.insert(std::make_pair(event_id, new_message));
        return new_message;
    }

    // Returns empty string on error
    static const char* file_get_filename(const std::string &filepath) {
        size_t index = filepath.rfind('/');
        if(index == std::string::npos)
            return "";
        const char *filename = filepath.c_str() + index + 1;
        if(filename[0] == '\0')
            return "";
        return filename;
    }

    PluginResult Matrix::post_file(std::shared_ptr<RoomData> room, const std::string &filepath, std::string &err_msg) {
        UploadInfo file_info;
        UploadInfo thumbnail_info;
        PluginResult upload_file_result = upload_file(room, filepath, file_info, thumbnail_info, err_msg);
        if(upload_file_result != PluginResult::OK)
            return upload_file_result;

        std::optional<UploadInfo> file_info_opt = std::move(file_info);
        std::optional<UploadInfo> thumbnail_info_opt;
        if(!thumbnail_info.content_uri.empty())
            thumbnail_info_opt = std::move(thumbnail_info);

        const char *filename = file_get_filename(filepath);
        return post_message(room, filename, file_info_opt, thumbnail_info_opt);
    }

    PluginResult Matrix::upload_file(std::shared_ptr<RoomData> room, const std::string &filepath, UploadInfo &file_info, UploadInfo &thumbnail_info, std::string &err_msg) {
        FileAnalyzer file_analyzer;
        if(!file_analyzer.load_file(filepath.c_str())) {
            err_msg = "Failed to load " + filepath;
            return PluginResult::ERR;
        }

        file_info.content_type = file_analyzer.get_content_type();
        file_info.file_size = file_analyzer.get_file_size();
        file_info.dimensions = file_analyzer.get_dimensions();
        file_info.duration_seconds = file_analyzer.get_duration_seconds();

        int upload_limit;
        PluginResult config_result = get_config(&upload_limit);
        if(config_result != PluginResult::OK) {
            err_msg = "Failed to get file size limit from server";
            return config_result;
        }

        // Checking for sane file size limit client side, to prevent loading a huge file and crashing
        if(file_analyzer.get_file_size() > 300 * 1024 * 1024) { // 300mb
            err_msg = "File is too large! client-side limit is set to 300mb";
            return PluginResult::ERR;
        }

        if((int)file_analyzer.get_file_size() > upload_limit) {
            err_msg = "File is too large! max upload size on your homeserver is " + std::to_string(upload_limit) + " bytes, the file you tried to upload is " + std::to_string(file_analyzer.get_file_size()) + " bytes";
            return PluginResult::ERR;
        }

        if(is_content_type_video(file_analyzer.get_content_type())) {
            // TODO: Also upload thumbnail for images. Take into consideration below upload_file, we dont want to upload thumbnail of thumbnail
            char tmp_filename[] = "/tmp/quickmedia_video_frame_XXXXXX";
            int tmp_file = mkstemp(tmp_filename);
            if(tmp_file != -1) {
                if(video_get_first_frame(filepath.c_str(), tmp_filename)) {
                    UploadInfo upload_info_ignored; // Ignore because it wont be set anyways. Thumbnails dont have thumbnails.
                    PluginResult upload_thumbnail_result = upload_file(room, tmp_filename, thumbnail_info, upload_info_ignored, err_msg);
                    if(upload_thumbnail_result != PluginResult::OK) {
                        close(tmp_file);
                        remove(tmp_filename);
                        return upload_thumbnail_result;
                    }
                } else {
                    fprintf(stderr, "Failed to get first frame of video, ignoring thumbnail...\n");
                }
                close(tmp_file);
                remove(tmp_filename);
            } else {
                fprintf(stderr, "Failed to create temporary file for video thumbnail, ignoring thumbnail...\n");
            }
        }

        std::vector<CommandArg> additional_args = {
            { "-X", "POST" },
            { "-H", std::string("content-type: ") + content_type_to_string(file_analyzer.get_content_type()) },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", "@" + filepath }
        };

        const char *filename = file_get_filename(filepath);
        std::string filename_escaped = url_param_encode(filename);

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/media/r0/upload?filename=%s", homeserver.c_str(), filename_escaped.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true, &err_msg);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject()) {
            err_msg = "Got corrupt response from server";
            return PluginResult::ERR;
        }

        const rapidjson::Value &error_json = GetMember(json_root, "error");
        if(error_json.IsString()) {
            err_msg = error_json.GetString();
            return PluginResult::ERR;
        }

        const rapidjson::Value &content_uri_json = GetMember(json_root, "content_uri");
        if(!content_uri_json.IsString()) {
            err_msg = "Missing content_uri is server response";
            return PluginResult::ERR;
        }

        fprintf(stderr, "Matrix upload, response content uri: %s\n", content_uri_json.GetString());
        file_info.content_uri = content_uri_json.GetString();
        return PluginResult::OK;
    }

    PluginResult Matrix::login(const std::string &username, const std::string &password, const std::string &homeserver, std::string &err_msg) {
        rapidjson::Document identifier_json(rapidjson::kObjectType);
        identifier_json.AddMember("type", "m.id.user", identifier_json.GetAllocator()); // TODO: What if the server doesn't support this login type? redirect to sso web page etc
        identifier_json.AddMember("user", rapidjson::StringRef(username.c_str()), identifier_json.GetAllocator());

        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("type", "m.login.password", request_data.GetAllocator());
        request_data.AddMember("identifier", std::move(identifier_json), request_data.GetAllocator());
        request_data.AddMember("password", rapidjson::StringRef(password.c_str()), request_data.GetAllocator());
        request_data.AddMember("initial_device_display_name", "QuickMedia", request_data.GetAllocator()); // :^)

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "POST" },
            { "-H", "content-type: application/json" },
            { "--data-binary", buffer.GetString() }
        };

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, homeserver + "/_matrix/client/r0/login", std::move(additional_args), true, &err_msg);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject()) {
            err_msg = "Failed to parse matrix login response";
            return PluginResult::ERR;
        }

        const rapidjson::Value &error_json = GetMember(json_root, "error");
        if(error_json.IsString()) {
            err_msg = error_json.GetString();
            return PluginResult::ERR;
        }

        const rapidjson::Value &user_id_json = GetMember(json_root, "user_id");
        if(!user_id_json.IsString()) {
            err_msg = "Failed to parse matrix login response";
            return PluginResult::ERR;
        }

        const rapidjson::Value &access_token_json = GetMember(json_root, "access_token");
        if(!access_token_json.IsString()) {
            err_msg = "Failed to parse matrix login response";
            return PluginResult::ERR;
        }

        // Use the user-provided homeserver instead of the one the server tells us about, otherwise this wont work with a proxy
        // such as pantalaimon
        json_root.AddMember("homeserver", rapidjson::StringRef(homeserver.c_str()), request_data.GetAllocator());

        this->user_id = user_id_json.GetString();
        this->username = extract_user_name_from_user_id(this->user_id);
        this->access_token = access_token_json.GetString();
        this->homeserver = homeserver;

        // TODO: Handle well_known field. The spec says clients SHOULD handle it if its provided

        Path session_path = get_storage_dir().join(SERVICE_NAME);
        if(create_directory_recursive(session_path) == 0) {
            session_path.join("session.json");
            if(!save_json_to_file_atomic(session_path, json_root)) {
                fprintf(stderr, "Warning: failed to save login response to %s\n", session_path.data.c_str());
            }
        } else {
            fprintf(stderr, "Warning: failed to create directory: %s\n", session_path.data.c_str());
        }

        return PluginResult::OK;
    }

    PluginResult Matrix::logout() {
        Path session_path = get_storage_dir().join(SERVICE_NAME).join("session.json");
        remove(session_path.data.c_str());

        std::vector<CommandArg> additional_args = {
            { "-X", "POST" },
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string server_response;
        if(download_to_string(homeserver + "/_matrix/client/r0/logout", server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        // Make sure all fields are reset here!
        rooms.clear();
        room_data_by_id.clear();
        user_id.clear();
        username.clear();
        access_token.clear();
        homeserver.clear();
        upload_limit.reset();
        next_batch.clear();

        return PluginResult::OK;
    }

    PluginResult Matrix::delete_message(std::shared_ptr<RoomData> room, void *message, std::string &err_msg){
        char random_characters[18];
        if(!generate_random_characters(random_characters, sizeof(random_characters)))
            return PluginResult::ERR;

        std::string random_readable_chars = random_characters_to_readable_string(random_characters, sizeof(random_characters));

        Message *message_typed = (Message*)message;

        // request_data could contains "reason", maybe it should be added sometime in the future?
        rapidjson::Value request_data(rapidjson::kObjectType);
        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", buffer.GetString() }
        };

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/client/r0/rooms/%s/redact/%s/m%ld.%.*s", homeserver.c_str(), room->id.c_str(), message_typed->event_id.c_str(), time(NULL), (int)random_readable_chars.size(), random_readable_chars.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true, &err_msg);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject()) {
            err_msg = "Failed to parse matrix login response";
            return PluginResult::ERR;
        }

        const rapidjson::Value &error_json = GetMember(json_root, "error");
        if(error_json.IsString()) {
            err_msg = error_json.GetString();
            return PluginResult::ERR;
        }

        const rapidjson::Value &event_id_json = GetMember(json_root, "event_id");
        if(!event_id_json.IsString())
            return PluginResult::ERR;

        fprintf(stderr, "Matrix delete message, response event id: %s\n", event_id_json.GetString());
        return PluginResult::OK;
    }

    PluginResult Matrix::load_and_verify_cached_session() {
        Path session_path = get_storage_dir().join(SERVICE_NAME).join("session.json");
        std::string session_json_content;
        if(file_get_content(session_path, session_json_content) != 0) {
            fprintf(stderr, "Info: failed to read matrix session from %s. Either its missing or we failed to read the file\n", session_path.data.c_str());
            return PluginResult::ERR;
        }

        rapidjson::Document json_root;
        rapidjson::ParseResult parse_result = json_root.Parse(session_json_content.c_str(), session_json_content.size());
        if(parse_result.IsError()) {
            fprintf(stderr, "Matrix cached session parse error: %d\n", parse_result.Code());
            return PluginResult::ERR;
        }

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &user_id_json = GetMember(json_root, "user_id");
        if(!user_id_json.IsString()) {
            fprintf(stderr, "Failed to parse matrix cached session response\n");
            return PluginResult::ERR;
        }

        const rapidjson::Value &access_token_json = GetMember(json_root, "access_token");
        if(!access_token_json.IsString()) {
            fprintf(stderr, "Failed to parse matrix cached session response\n");
            return PluginResult::ERR;
        }

        const rapidjson::Value &homeserver_json = GetMember(json_root, "homeserver");
        if(!homeserver_json.IsString()) {
            fprintf(stderr, "Failed to parse matrix cached session response\n");
            return PluginResult::ERR;
        }

        std::string user_id = user_id_json.GetString();
        std::string access_token = access_token_json.GetString();
        std::string homeserver = homeserver_json.GetString();

        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string server_response;
        // We want to make any request to the server that can verify that our token is still valid, doesn't matter which call
        if(download_to_string(homeserver + "/_matrix/client/r0/account/whoami", server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK) {
            fprintf(stderr, "Matrix whoami response: %s\n", server_response.c_str());
            return PluginResult::NET_ERR;
        }

        this->user_id = std::move(user_id);
        this->username = extract_user_name_from_user_id(this->user_id);
        this->access_token = std::move(access_token);
        this->homeserver = std::move(homeserver);
        return PluginResult::OK;
    }

    PluginResult Matrix::on_start_typing(std::shared_ptr<RoomData> room) {
        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("typing", true, request_data.GetAllocator());
        request_data.AddMember("timeout", 30000, request_data.GetAllocator()); // 30 sec timeout

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "--data-binary", buffer.GetString() },
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string server_response;
        if(download_to_string(homeserver + "/_matrix/client/r0/rooms/" + room->id + "/typing/" + url_param_encode(user_id) , server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        return PluginResult::OK;
    }

    PluginResult Matrix::on_stop_typing(std::shared_ptr<RoomData> room) {
        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("typing", false, request_data.GetAllocator());

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "--data-binary", buffer.GetString() },
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string server_response;
        if(download_to_string(homeserver + "/_matrix/client/r0/rooms/" + room->id + "/typing/" + url_param_encode(user_id), server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        return PluginResult::OK;
    }

    PluginResult Matrix::set_read_marker(std::shared_ptr<RoomData> room, const Message *message) {
        rapidjson::Document request_data(rapidjson::kObjectType);
        request_data.AddMember("m.fully_read", rapidjson::StringRef(message->event_id.c_str()), request_data.GetAllocator());
        request_data.AddMember("m.read", rapidjson::StringRef(message->event_id.c_str()), request_data.GetAllocator());
        request_data.AddMember("m.hidden", false, request_data.GetAllocator()); // What is this for? element sends it but its not part of the documentation. Is it for hiding read receipt from other users? in that case, TODO: make it configurable

        rapidjson::StringBuffer buffer;
        rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
        request_data.Accept(writer);

        std::vector<CommandArg> additional_args = {
            { "-X", "POST" },
            { "-H", "content-type: application/json" },
            { "--data-binary", buffer.GetString() },
            { "-H", "Authorization: Bearer " + access_token }
        };

        std::string server_response;
        if(download_to_string(homeserver + "/_matrix/client/r0/rooms/" + room->id + "/read_markers", server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        return PluginResult::OK;
    }

    bool Matrix::was_message_posted_by_me(void *message) {
        Message *message_typed = (Message*)message;
        return user_id == message_typed->user->user_id;
    }

    std::string Matrix::message_get_author_displayname(Message *message) const {
        // TODO: Thread safe?
        return message->user->display_name;
    }

    PluginResult Matrix::get_config(int *upload_size) {
        // TODO: What if the upload limit changes? is it possible for the upload limit to change while the server is running?
        if(upload_limit) {
            *upload_size = upload_limit.value();
            return PluginResult::OK;
        }

        *upload_size = 0;

        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token }
        };

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/media/r0/config", homeserver.c_str());

        rapidjson::Document json_root;
        DownloadResult download_result = download_json(json_root, url, std::move(additional_args), true);
        if(download_result != DownloadResult::OK) return download_result_to_plugin_result(download_result);

        if(!json_root.IsObject())
            return PluginResult::ERR;

        const rapidjson::Value &upload_size_json = GetMember(json_root, "m.upload.size");
        if(!upload_size_json.IsNumber())
            return PluginResult::ERR;

        upload_limit = upload_size_json.GetInt();
        *upload_size = upload_limit.value();
        return PluginResult::OK;
    }

    std::shared_ptr<UserInfo> Matrix::get_me(std::shared_ptr<RoomData> room) {
        return room->get_user_by_id(user_id);
    }

    std::shared_ptr<RoomData> Matrix::get_room_by_id(const std::string &id) {
        std::lock_guard<std::mutex> lock(room_data_mutex);
        auto room_it = room_data_by_id.find(id);
        if(room_it == room_data_by_id.end())
            return nullptr;
        return rooms[room_it->second];
    }

    void Matrix::add_room(std::shared_ptr<RoomData> room) {
        std::lock_guard<std::mutex> lock(room_data_mutex);
        room_data_by_id.insert(std::make_pair(room->id, rooms.size()));
        rooms.push_back(room);
    }

    DownloadResult Matrix::download_json(rapidjson::Document &result, const std::string &url, std::vector<CommandArg> additional_args, bool use_browser_useragent, std::string *err_msg) const {
        if(download_to_json(url, result, std::move(additional_args), use_tor, use_browser_useragent, err_msg == nullptr) != DownloadResult::OK) {
            // Cant get error since we parse directory to json. TODO: Make this work somehow?
            if(err_msg)
                *err_msg = "Failed to download/parse json";
            return DownloadResult::NET_ERR;
        }
        return DownloadResult::OK;
    }
}