path: root/src/plugins/Matrix.cpp

#include "../../plugins/Matrix.hpp"
#include "../../include/Storage.hpp"
#include "../../include/ImageUtils.hpp"
#include <json/reader.h>
#include <json/writer.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.

namespace QuickMedia {
    Matrix::Matrix() : Plugin("matrix") {
        
    }

    PluginResult Matrix::get_cached_sync(BodyItems &result_items) {
        /*
        Path sync_cache_path = get_cache_dir().join(name).join("sync.json");
        Json::Value root;
        if(!read_file_as_json(sync_cache_path, root))
            return PluginResult::ERR;
        return sync_response_to_body_items(root, result_items);
        */
        (void)result_items;
        return PluginResult::OK;
    }

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

        std::string server_response;
        // timeout=30000, filter=0. First sync should be without filter and timeout=0, then all other sync should be with timeout=30000 and filter=0.
        // GET https://glowers.club/_matrix/client/r0/user/%40dec05eba%3Aglowers.club/filter/0 first to check if the filter is available
        // and if lazy load members is available and get limit to use with https://glowers.club/_matrix/client/r0/rooms/!oSXkiqBKooDcZsmiGO%3Aglowers.club/
        // when first launching the client. This call to /rooms/ should be called before /sync/, when accessing a room. But only the first time
        // (for the session).

        // Note: the first sync call with always exclude since= (next_batch) because we want to receive the latest messages in a room,
        // which is important if we for example login to matrix after having not been online for several days and there are many new messages.
        // We should be shown the latest messages first and if the user wants to see older messages then they should scroll up.
        // Note: missed mentions are received in /sync and they will remain in new /sync unless we send a read receipt that we have read them.

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

        if(download_to_string(url, server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        if(server_response.empty())
            return PluginResult::ERR;
        
        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix sync response parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

        const Json::Value &next_batch_json = json_root["next_batch"];
        if(next_batch_json.isString()) {
            next_batch = next_batch_json.asString();
            fprintf(stderr, "Matrix: next batch: %s\n", next_batch.c_str());
        } else {
            fprintf(stderr, "Matrix: missing next batch\n");
        }

        // TODO: Only create the first time sync is called?
        /*
        Path sync_cache_path = get_cache_dir().join(name);
        if(create_directory_recursive(sync_cache_path) == 0) {
            sync_cache_path.join("sync.json");
            if(!save_json_to_file_atomic(sync_cache_path, json_root)) {
                fprintf(stderr, "Warning: failed to save sync response to %s\n", sync_cache_path.data.c_str());
            }
        } else {
            fprintf(stderr, "Warning: failed to create directory: %s\n", sync_cache_path.data.c_str());
        }
        */

        return PluginResult::OK;
    }

    PluginResult Matrix::get_joined_rooms(BodyItems &result_items) {
        std::vector<CommandArg> additional_args = {
            { "-H", "Authorization: Bearer " + access_token }
        };

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

        if(server_response.empty())
            return PluginResult::ERR;
        
        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix joined rooms response parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

        const Json::Value &joined_rooms_json = json_root["joined_rooms"];
        if(!joined_rooms_json.isArray())
            return PluginResult::ERR;

        for(const Json::Value &room_id_json : joined_rooms_json) {
            if(!room_id_json.isString())
                continue;

            std::string room_id_str = room_id_json.asString();
            std::string room_name;
            std::string avatar_url;

            auto room_it = room_data_by_id.find(room_id_str);
            if(room_it == room_data_by_id.end()) {
                auto room_data = std::make_unique<RoomData>();
                room_data_by_id.insert(std::make_pair(room_id_str, std::move(room_data)));
                room_name = room_id_str;
                fprintf(stderr, "Missing room %s from /sync, adding in joined_rooms\n", room_id_str.c_str());
            } else {
                room_name = room_it->second->name;
                if(room_name.empty())
                    room_name = room_id_str;
                avatar_url = room_it->second->avatar_url;
            }

            auto body_item = std::make_unique<BodyItem>(std::move(room_name));
            body_item->url = room_id_str;
            body_item->thumbnail_url = std::move(avatar_url);
            result_items.push_back(std::move(body_item));
        }

        return PluginResult::OK;
    }

    static void room_messages_to_body_items(RoomData *room_data, Message *messages, size_t num_messages, BodyItems &result_items) {
        for(size_t i = 0; i < num_messages; ++i) {
            const UserInfo &user_info = room_data->user_info[messages[i].user_id];
            auto body_item = std::make_unique<BodyItem>("");
            body_item->set_author(user_info.display_name);
            body_item->set_description(messages[i].body);
            if(!messages[i].thumbnail_url.empty())
                body_item->thumbnail_url = messages[i].thumbnail_url;
            else if(!messages[i].url.empty() && messages->type == MessageType::IMAGE)
                body_item->thumbnail_url = messages[i].url;
            else
                body_item->thumbnail_url = user_info.avatar_url;
            // TODO: Show image thumbnail inline instead of url to image and showing it as the thumbnail of the body item
            body_item->url = messages[i].url;
            body_item->author_color = user_info.display_name_color;
            result_items.push_back(std::move(body_item));
        }
    }

    // TODO: Merge common code with |get_new_room_messages|
    PluginResult Matrix::get_all_synced_room_messages(const std::string &room_id, BodyItems &result_items) {
        auto room_it = room_data_by_id.find(room_id);
        if(room_it == room_data_by_id.end()) {
            fprintf(stderr, "Error: no such room: %s\n", room_id.c_str());
            return PluginResult::ERR;
        }

        if(!room_it->second->initial_fetch_finished) {
            PluginResult result = get_previous_room_messages(room_id, room_it->second.get());
            if(result == PluginResult::OK) {
                room_it->second->initial_fetch_finished = true;
            } else {
                fprintf(stderr, "Initial sync failed for room: %s\n", room_id.c_str());
                return result;
            }
        }

        room_messages_to_body_items(room_it->second.get(), room_it->second->messages.data(), room_it->second->messages.size(), result_items);
        room_it->second->last_read_index = room_it->second->messages.size();
        return PluginResult::OK;
    }

    PluginResult Matrix::get_new_room_messages(const std::string &room_id, BodyItems &result_items) {
        auto room_it = room_data_by_id.find(room_id);
        if(room_it == room_data_by_id.end()) {
            fprintf(stderr, "Error: no such room: %s\n", room_id.c_str());
            return PluginResult::ERR;
        }

        if(!room_it->second->initial_fetch_finished) {
            PluginResult result = get_previous_room_messages(room_id, room_it->second.get());
            if(result == PluginResult::OK) {
                room_it->second->initial_fetch_finished = true;
            } else {
                fprintf(stderr, "Initial sync failed for room: %s\n", room_id.c_str());
                return result;
            }
        }

        size_t num_new_messages = room_it->second->messages.size() - room_it->second->last_read_index;
        room_messages_to_body_items(room_it->second.get(), room_it->second->messages.data() + room_it->second->last_read_index, num_new_messages, result_items);
        room_it->second->last_read_index = room_it->second->messages.size();
        return PluginResult::OK;
    }

    PluginResult Matrix::get_previous_room_messages(const std::string &room_id, BodyItems &result_items) {
        auto room_it = room_data_by_id.find(room_id);
        if(room_it == room_data_by_id.end()) {
            fprintf(stderr, "Error: no such room: %s\n", room_id.c_str());
            return PluginResult::ERR;
        }
        
        size_t num_messages_before = room_it->second->messages.size();
        PluginResult result = get_previous_room_messages(room_id, room_it->second.get());
        if(result != PluginResult::OK)
            return result;

        size_t num_messages_after = room_it->second->messages.size();
        size_t num_new_messages = num_messages_after - num_messages_before;
        room_messages_to_body_items(room_it->second.get(), room_it->second->messages.data(), num_new_messages, result_items);
        return PluginResult::OK;
    }

    PluginResult Matrix::sync_response_to_body_items(const Json::Value &root) {
        if(!root.isObject())
            return PluginResult::ERR;

        const Json::Value &rooms_json = root["rooms"];
        if(!rooms_json.isObject())
            return PluginResult::OK;

        const Json::Value &join_json = rooms_json["join"];
        if(!join_json.isObject())
            return PluginResult::OK;

        for(Json::Value::const_iterator it = join_json.begin(); it != join_json.end(); ++it) {
            if(!it->isObject())
                continue;

            Json::Value room_id = it.key();
            if(!room_id.isString())
                continue;

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

            auto room_it = room_data_by_id.find(room_id_str);
            if(room_it == room_data_by_id.end()) {
                auto room_data = std::make_unique<RoomData>();
                room_data_by_id.insert(std::make_pair(room_id_str, std::move(room_data)));
                room_it = room_data_by_id.find(room_id_str); // TODO: Get iterator from above insert
            }

            const Json::Value &state_json = (*it)["state"];
            if(!state_json.isObject())
                continue;

            const Json::Value &events_json = state_json["events"];
            events_add_user_info(events_json, room_it->second.get());
            events_set_room_name(events_json, room_it->second.get());
        }

        for(Json::Value::const_iterator it = join_json.begin(); it != join_json.end(); ++it) {
            if(!it->isObject())
                continue;

            Json::Value room_id = it.key();
            if(!room_id.isString())
                continue;

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

            auto room_it = room_data_by_id.find(room_id_str);
            if(room_it == room_data_by_id.end()) {
                auto room_data = std::make_unique<RoomData>();
                room_data_by_id.insert(std::make_pair(room_id_str, std::move(room_data)));
                room_it = room_data_by_id.find(room_id_str); // TODO: Get iterator from above insert
            }

            const Json::Value &timeline_json = (*it)["timeline"];
            if(!timeline_json.isObject())
                continue;

            if(room_it->second->prev_batch.empty()) {
                // This may be non-existent if this is the first event in the room
                const Json::Value &prev_batch_json = timeline_json["prev_batch"];
                if(prev_batch_json.isString())
                    room_it->second->prev_batch = prev_batch_json.asString();
            }

            const Json::Value &events_json = timeline_json["events"];
            events_add_user_info(events_json, room_it->second.get());
            events_add_messages(events_json, room_it->second.get(), MessageDirection::AFTER);
            events_set_room_name(events_json, room_it->second.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::Color result = (sf::Color)color;
        result.r = 64 + std::max(0, (int)result.r - 64);
        result.g = 64 + std::max(0, (int)result.g - 64);
        result.b = 64 + std::max(0, (int)result.b - 64);
        result.a = 255;
        return result;
    }

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

        for(const Json::Value &event_item_json : events_json) {
            if(!event_item_json.isObject())
                continue;

            const Json::Value &type_json = event_item_json["type"];
            if(!type_json.isString() || strcmp(type_json.asCString(), "m.room.member") != 0)
                continue;

            const Json::Value &sender_json = event_item_json["sender"];
            if(!sender_json.isString())
                continue;
            
            const Json::Value &content_json = event_item_json["content"];
            if(!content_json.isObject())
                continue;

            const Json::Value &membership_json = content_json["membership"];
            if(!membership_json.isString() || strcmp(membership_json.asCString(), "join") != 0)
                continue;

            const Json::Value &avatar_url_json = content_json["avatar_url"];
            if(!avatar_url_json.isString())
                continue;

            const Json::Value &display_name_json = content_json["displayname"];
            if(!display_name_json.isString())
                continue;
            
            std::string sender_json_str = sender_json.asString();
            auto user_it = room_data->user_info_by_user_id.find(sender_json_str);
            if(user_it != room_data->user_info_by_user_id.end())
                continue;

            UserInfo user_info;
            user_info.avatar_url = avatar_url_json.asString();
            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);
            // TODO: What if the user hasn't selected an avatar?
            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.asString();
            user_info.display_name_color = user_id_to_color(sender_json_str);
            room_data->user_info.push_back(std::move(user_info));
            room_data->user_info_by_user_id.insert(std::make_pair(sender_json_str, room_data->user_info.size() - 1));
        }
    }

    static std::string message_content_extract_thumbnail_url(const Json::Value &content_json, const std::string &homeserver) {
        const Json::Value &info_json = content_json["info"];
        if(info_json.isObject()) {
            const Json::Value &thumbnail_url_json = info_json["thumbnail_url"];
            if(thumbnail_url_json.isString()) {
                std::string thumbnail_str = thumbnail_url_json.asString();
                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 "";
    }

    void Matrix::events_add_messages(const Json::Value &events_json, RoomData *room_data, MessageDirection message_dir) {
        if(!events_json.isArray())
            return;

        std::vector<Message> new_messages;

        for(const Json::Value &event_item_json : events_json) {
            if(!event_item_json.isObject())
                continue;

            const Json::Value &type_json = event_item_json["type"];
            if(!type_json.isString() || strcmp(type_json.asCString(), "m.room.message") != 0)
                continue;

            const Json::Value &sender_json = event_item_json["sender"];
            if(!sender_json.isString())
                continue;

            std::string sender_json_str = sender_json.asString();
            
            const Json::Value &content_json = event_item_json["content"];
            if(!content_json.isObject())
                continue;

            const Json::Value &content_type = content_json["msgtype"];
            if(!content_type.isString())
                continue;

            auto user_it = room_data->user_info_by_user_id.find(sender_json_str);
            if(user_it == room_data->user_info_by_user_id.end()) {
                fprintf(stderr, "Warning: skipping unknown user: %s\n", sender_json_str.c_str());
                continue;
            }

            const Json::Value &body_json = content_json["body"];
            if(!body_json.isString())
                continue;

            if(strcmp(content_type.asCString(), "m.text") == 0) {
                Message message;
                message.user_id = user_it->second;
                message.body = body_json.asString();
                message.type = MessageType::TEXT;
                new_messages.push_back(std::move(message));
            } else if(strcmp(content_type.asCString(), "m.image") == 0) {
                const Json::Value &url_json = content_json["url"];
                if(!url_json.isString() || strncmp(url_json.asCString(), "mxc://", 6) != 0)
                    continue;

                Message message;
                message.user_id = user_it->second;
                message.body = body_json.asString();
                message.url = homeserver + "/_matrix/media/r0/download/" + url_json.asString().substr(6);
                message.thumbnail_url = message_content_extract_thumbnail_url(content_json, homeserver);
                message.type = MessageType::IMAGE;
                new_messages.push_back(std::move(message));
            } else if(strcmp(content_type.asCString(), "m.video") == 0) {
                const Json::Value &url_json = content_json["url"];
                if(!url_json.isString() || strncmp(url_json.asCString(), "mxc://", 6) != 0)
                    continue;

                Message message;
                message.user_id = user_it->second;
                message.body = body_json.asString();
                message.url = homeserver + "/_matrix/media/r0/download/" + url_json.asString().substr(6);
                message.thumbnail_url = message_content_extract_thumbnail_url(content_json, homeserver);
                message.type = MessageType::VIDEO;
                new_messages.push_back(std::move(message));
            }
        }

        // TODO: Loop and std::move instead? doesn't insert create copies?
        if(message_dir == MessageDirection::BEFORE) {
            room_data->messages.insert(room_data->messages.begin(), new_messages.rbegin(), new_messages.rend());
            if(room_data->last_read_index != 0)
                room_data->last_read_index += new_messages.size();
        } else if(message_dir == MessageDirection::AFTER) {
            room_data->messages.insert(room_data->messages.end(), new_messages.begin(), new_messages.end());
        }
    }

    // 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);
    }

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

        for(const Json::Value &event_item_json : events_json) {
            if(!event_item_json.isObject())
                continue;

            const Json::Value &type_json = event_item_json["type"];
            if(!type_json.isString() || strcmp(type_json.asCString(), "m.room.name") != 0)
                continue;
            
            const Json::Value &content_json = event_item_json["content"];
            if(!content_json.isObject())
                continue;

            const Json::Value &name_json = content_json["name"];
            if(!name_json.isString())
                continue;

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

        for(const Json::Value &event_item_json : events_json) {
            if(!event_item_json.isObject())
                continue;

            const Json::Value &type_json = event_item_json["type"];
            if(!type_json.isString() || strcmp(type_json.asCString(), "m.room.create") != 0)
                continue;
            
            const Json::Value &content_json = event_item_json["content"];
            if(!content_json.isObject())
                continue;

            const Json::Value &creator_json = content_json["creator"];
            if(!creator_json.isString())
                continue;

            if(room_data->name.empty())
                room_data->name = extract_user_name_from_user_id(creator_json.asString());

            if(room_data->avatar_url.empty()) {
                auto user_it = room_data->user_info_by_user_id.find(creator_json.asString());
                if(user_it != room_data->user_info_by_user_id.end())
                    room_data->avatar_url = room_data->user_info[user_it->second].avatar_url;
            }
        }

        for(const Json::Value &event_item_json : events_json) {
            if(!event_item_json.isObject())
                continue;

            const Json::Value &type_json = event_item_json["type"];
            if(!type_json.isString() || strcmp(type_json.asCString(), "m.room.avatar") != 0)
                continue;
            
            const Json::Value &content_json = event_item_json["content"];
            if(!content_json.isObject())
                continue;

            const Json::Value &url_json = content_json["url"];
            if(!url_json.isString() || strncmp(url_json.asCString(), "mxc://", 6) != 0)
                continue;

            std::string url_json_str = url_json.asCString() + 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(const std::string &room_id, 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_id.c_str());
            from = next_batch;
            if(from.empty()) {
                fprintf(stderr, "Error: missing next batch!\n");
                return PluginResult::OK;
            }
        }

        Json::Value request_data(Json::objectValue);
        request_data["lazy_load_members"] = true;

        Json::StreamWriterBuilder builder;
        builder["commentStyle"] = "None";
        builder["indentation"] = "";

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

        std::string filter = url_param_encode(Json::writeString(builder, std::move(request_data)));

        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_id.c_str(), from.c_str(), filter.c_str());
        fprintf(stderr, "load initial room data, url: |%s|\n", url);

        std::string server_response;
        if(download_to_string(url, server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        if(server_response.empty())
            return PluginResult::ERR;
        
        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix /rooms/<room_id>/messages/ response parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

        const Json::Value &state_json = json_root["state"];
        events_add_user_info(state_json, room_data);
        events_set_room_name(state_json, room_data);

        const Json::Value &chunk_json = json_root["chunk"];
        events_add_messages(chunk_json, room_data, MessageDirection::BEFORE);

        const Json::Value &end_json = 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.asString();
        return PluginResult::OK;
    }

    SearchResult Matrix::search(const std::string&, BodyItems&) {
        return SearchResult::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* message_type_to_request_msg_type_str(MessageType msgtype) {
        switch(msgtype) {
            case MessageType::TEXT:     return "m.text";
            case MessageType::IMAGE:    return "m.image";
            case MessageType::VIDEO:    return "m.video";
        }
        return "m.text";
    }

    PluginResult Matrix::post_message(const std::string &room_id, const std::string &body, const std::string &url, MessageType msgtype, MessageInfo *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(msgtype == MessageType::TEXT) {
            string_split(body, '\n', [&formatted_body, &contains_formatted_text](const char *str, size_t size){
                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);
                }
                return true;
            });
        }

        Json::Value request_data(Json::objectValue);
        request_data["msgtype"] = message_type_to_request_msg_type_str(msgtype);
        request_data["body"] = body;
        if(contains_formatted_text) {
            request_data["format"] = "org.matrix.custom.html";
            request_data["formatted_body"] = std::move(formatted_body);
        }
        if(msgtype == MessageType::IMAGE) {
            if(info) {
                Json::Value info_json(Json::objectValue);
                info_json["size"] = info->size;
                info_json["w"] = info->w;
                info_json["h"] = info->h;
                info_json["mimetype"] = info->mimetype;
                request_data["info"] = std::move(info_json);
            }
            request_data["url"] = url;
        }

        Json::StreamWriterBuilder builder;
        builder["commentStyle"] = "None";
        builder["indentation"] = "";

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "-H", "Authorization: Bearer " + access_token },
            { "--data-binary", Json::writeString(builder, std::move(request_data)) }
        };

        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());
        fprintf(stderr, "Post message to |%s|\n", request_url);

        std::string server_response;
        if(download_to_string(request_url, server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        if(server_response.empty())
            return PluginResult::ERR;

        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix post message response parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

        const Json::Value &event_id_json = 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.asCString());
        return PluginResult::OK;
    }

    // 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;
    }

    static const char* image_type_to_mimetype(ImageType image_type) {
        switch(image_type) {
            case ImageType::PNG:    return "image/png";
            case ImageType::GIF:    return "image/gif";
            case ImageType::JPG:    return "image/jpeg";
        }
        return "application/octet-stream";
    }

    PluginResult Matrix::post_file(const std::string &room_id, const std::string &filepath) {
        int image_width, image_height;
        ImageType image_type;
        if(!image_get_resolution(filepath, &image_width, &image_height, &image_type)) {
            fprintf(stderr, "Failed to get resolution of image: %s. Only image uploads are currently supported\n", filepath.c_str());
            return PluginResult::ERR;
        }

        const char *mimetype = image_type_to_mimetype(image_type);

        // TODO: What if the file changes after this? is the file size really needed?
        size_t file_size;
        if(file_get_size(filepath, &file_size) != 0) {
            fprintf(stderr, "Failed to get size of image: %s\n", filepath.c_str());
            return PluginResult::ERR;
        }

        // TODO: Check server file limit first: GET https://glowers.club/_matrix/media/r0/config
        // and also have a sane limit client-side.
        if(file_size > 100 * 1024 * 1024) {
            fprintf(stderr, "Upload file size it too large!, max size is currently 100mb\n");
            return PluginResult::ERR;
        }

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

        const char *filename = file_get_filename(filepath);

        char url[512];
        snprintf(url, sizeof(url), "%s/_matrix/media/r0/upload?filename=%s", homeserver.c_str(), filename);
        fprintf(stderr, "Upload url: |%s|\n", url);

        std::string server_response;
        if(download_to_string(url, server_response, std::move(additional_args), use_tor, true) != DownloadResult::OK)
            return PluginResult::NET_ERR;

        if(server_response.empty())
            return PluginResult::ERR;

        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix upload response parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

        const Json::Value &content_uri_json = json_root["content_uri"];
        if(!content_uri_json.isString())
            return PluginResult::ERR;

        fprintf(stderr, "Matrix upload, response content uri: %s\n", content_uri_json.asCString());
        MessageInfo message_info;
        message_info.size = file_size;
        message_info.w = image_width;
        message_info.h = image_height;
        message_info.mimetype = mimetype;
        return post_message(room_id, filename, content_uri_json.asString(), MessageType::IMAGE, &message_info);
    }

    PluginResult Matrix::login(const std::string &username, const std::string &password, const std::string &homeserver, std::string &err_msg) {
        Json::Value identifier_json(Json::objectValue);
        identifier_json["type"] = "m.id.user"; // TODO: What if the server doesn't support this login type? redirect to sso web page etc
        identifier_json["user"] = username;

        Json::Value request_data(Json::objectValue);
        request_data["type"] = "m.login.password";
        request_data["identifier"] = std::move(identifier_json);
        request_data["password"] = password;

        Json::StreamWriterBuilder builder;
        builder["commentStyle"] = "None";
        builder["indentation"] = "";

        std::vector<CommandArg> additional_args = {
            { "-X", "POST" },
            { "-H", "content-type: application/json" },
            { "--data-binary", Json::writeString(builder, std::move(request_data)) }
        };

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

        if(server_response.empty())
            return PluginResult::ERR;

        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&server_response[0], &server_response[server_response.size()], &json_root, &json_errors)) {
            err_msg = "Matrix login response parse error: " + json_errors;
            return PluginResult::ERR;
        }

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

        const Json::Value &error = json_root["error"];
        if(error.isString()) {
            err_msg = error.asString();
            return PluginResult::ERR;
        }

        const Json::Value &user_id_json = json_root["user_id"];
        if(!user_id_json.isString()) {
            err_msg = "Failed to parse matrix login response";
            return PluginResult::ERR;
        }

        const Json::Value &access_token_json = 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["homeserver"] = homeserver;

        this->user_id = user_id_json.asString();
        this->access_token = access_token_json.asString();
        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(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(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!
        room_data_by_id.clear();
        user_id.clear();
        access_token.clear();
        homeserver.clear();
        next_batch.clear();

        return PluginResult::OK;
    }

    PluginResult Matrix::load_and_verify_cached_session() {
        Path session_path = get_storage_dir().join(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;
        }

        Json::Value json_root;
        Json::CharReaderBuilder json_builder;
        std::unique_ptr<Json::CharReader> json_reader(json_builder.newCharReader());
        std::string json_errors;
        if(!json_reader->parse(&session_json_content[0], &session_json_content[session_json_content.size()], &json_root, &json_errors)) {
            fprintf(stderr, "Matrix cached session parse error: %s\n", json_errors.c_str());
            return PluginResult::ERR;
        }

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

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

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

        const Json::Value &homeserver_json = 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.asString();
        std::string access_token = access_token_json.asString();
        std::string homeserver = homeserver_json.asString();

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

    PluginResult Matrix::on_start_typing(const std::string &room_id) {
        Json::Value request_data(Json::objectValue);
        request_data["typing"] = true;
        request_data["timeout"] = 30000; // 30 sec timeout

        Json::StreamWriterBuilder builder;
        builder["commentStyle"] = "None";
        builder["indentation"] = "";

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "--data-binary", Json::writeString(builder, std::move(request_data)) },
            { "-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(const std::string &room_id) {
        Json::Value request_data(Json::objectValue);
        request_data["typing"] = false;

        Json::StreamWriterBuilder builder;
        builder["commentStyle"] = "None";
        builder["indentation"] = "";

        std::vector<CommandArg> additional_args = {
            { "-X", "PUT" },
            { "-H", "content-type: application/json" },
            { "--data-binary", Json::writeString(builder, std::move(request_data)) },
            { "-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;
    }
}