Introduce MaybeError type

src/core/deck.rs

@@ -6,7 +6,7 @@ use crate::core::srs::{
 use crate::data::entities::*;
 use crate::data_provider::card_stats::{load_stats_of_deck, update_stat_score};
 use crate::data_provider::history::push_note;
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use chrono::Utc;
 use parking_lot::Mutex;
 use std::sync::Arc;
@@ -88,7 +88,7 @@ impl DeckData {
         self.current_word_index = Some(index);
         (self.words[index].clone(), self.set[index].clone())
     }
-    pub fn open(&mut self, status: WordOpenMode) -> Result<(), NotificationData> {
+    pub fn open(&mut self, status: WordOpenMode) -> MaybeError {
         if let Some(index) = self.current_word_index {
             let word: &mut CardStatistics = &mut self.set[index];
             let old_score = word.score;

src/data_provider/card_sets.rs

@@ -2,7 +2,7 @@ use crate::core::srs::OrderMode;
 
 use crate::data::entities::DeckSettings;
 use rusqlite::Connection;
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::notification::NotificationData::{DbLoadError, DbSaveError};
 
 pub fn load_sets(connection: &Connection) -> Result<Vec<DeckSettings>, NotificationData> {
@@ -28,7 +28,7 @@ pub fn load_sets(connection: &Connection) -> Result<Vec<DeckSettings>, Notificat
     Ok(buffer)
 }
 
-pub fn add_set(set: &mut DeckSettings, connection: &Connection) -> Result<(), NotificationData> {
+pub fn add_set(set: &mut DeckSettings, connection: &Connection) -> MaybeError {
     let index : u32 = connection
         .query_row(
             "INSERT INTO card_set (name, forward, backward, filter) VALUES (?1, ?2, ?3, ?4) RETURNING id",
@@ -46,7 +46,7 @@ pub fn add_set(set: &mut DeckSettings, connection: &Connection) -> Result<(), No
     Ok(())
 }
 
-pub fn update_deck(set: &mut DeckSettings, connection: &Connection) -> Result<(), NotificationData> {
+pub fn update_deck(set: &mut DeckSettings, connection: &Connection) -> MaybeError {
     if !set.id.is_valid() {
         add_set(set, connection)?;
     } else {
@@ -66,7 +66,7 @@ pub fn update_deck(set: &mut DeckSettings, connection: &Connection) -> Result<()
     Ok(())
 }
 
-pub fn delete_set(set: &DeckSettings, connection: &Connection) -> Result<(), NotificationData> {
+pub fn delete_set(set: &DeckSettings, connection: &Connection) -> MaybeError {
     if !set.id.is_valid() {
         return Err(DbSaveError);
     }

src/data_provider/card_stats.rs

@@ -1,5 +1,5 @@
 use crate::data::entities::{CardStatistics, DeckSettings};
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::notification::NotificationData::{DbLoadError, DbSaveError};
 use log::info;
 use rusqlite::{Connection, params};
@@ -30,7 +30,7 @@ pub fn load_stats_of_deck(
     Ok(buffer)
 }
 
-pub fn add_stat_list(stats: &mut [CardStatistics], connection: &mut Connection) -> Result<(), NotificationData> {
+pub fn add_stat_list(stats: &mut [CardStatistics], connection: &mut Connection) -> MaybeError {
     let time = Instant::now();
     let tx = connection.transaction().expect("Failed to create transaction");
     let count = stats.len();
@@ -66,7 +66,7 @@ pub fn add_stat_list(stats: &mut [CardStatistics], connection: &mut Connection)
     Ok(())
 }
 
-pub fn update_stat_score(stat: &CardStatistics, connection: &Connection) -> Result<(), NotificationData> {
+pub fn update_stat_score(stat: &CardStatistics, connection: &Connection) -> MaybeError {
     let time = Instant::now();
 
     connection
@@ -79,7 +79,7 @@ pub fn update_stat_score(stat: &CardStatistics, connection: &Connection) -> Resu
     Ok(())
 }
 
-pub fn delete_stats(stat: &[CardStatistics], connection: &Connection) -> Result<(), NotificationData> {
+pub fn delete_stats(stat: &[CardStatistics], connection: &Connection) -> MaybeError {
     if stat.is_empty() {
         return Ok(());
     }

src/data_provider/history.rs

@@ -2,7 +2,7 @@ use crate::core::srs::WordOpenMode;
 use crate::data::Id;
 use crate::data::entities::HistoryItem;
 use crate::fs::*;
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::notification::NotificationData::PermissionDenied;
 use chrono::DateTime;
 use std::fs::{File, OpenOptions};
@@ -20,7 +20,7 @@ pub fn get_history_of_set(id: Id) -> Result<Vec<HistoryItem>, NotificationData>
     Ok(parse_history_items(lines))
 }
 
-fn append_lines_if_exists(path: PathBuf, lines: &mut Vec<String>) -> Result<(), NotificationData> {
+fn append_lines_if_exists(path: PathBuf, lines: &mut Vec<String>) -> MaybeError {
     if path.exists() {
         let reader = BufReader::new(File::open(path).map_err(|_| PermissionDenied)?);
         reader
@@ -63,7 +63,7 @@ fn parse_history_items(strings: Vec<String>) -> Vec<HistoryItem> {
     items
 }
 
-pub fn push_note(set_id: Id, item: HistoryItem) -> Result<(), NotificationData> {
+pub fn push_note(set_id: Id, item: HistoryItem) -> MaybeError {
     let app_dir = history_dir()?;
     let path = app_dir.clone().join(format!("set_{}_history.csv", set_id));
 

src/data_provider/import.rs

@@ -3,6 +3,8 @@ use hashbrown::HashMap;
 use log::info;
 use rusqlite::Connection;
 use serde_json::Value;
+use crate::helpers::into_result;
+use crate::notification::NotificationData::IncorrectAnkiFile;
 
 #[derive(Clone)]
 pub struct ImportData(pub(crate) Vec<ImportGroup>);
@@ -26,41 +28,40 @@ pub struct ImportNote {
 pub fn load_groups(connection: &Connection) -> Result<ImportData, NotificationData> {
     let json_models: String = connection
         .query_one("select models from col", (), |row| row.get(0))
-        .map_err(|_| NotificationData::IncorrectAnkiFile)?;
+        .map_err(|_| IncorrectAnkiFile)?;
     let raw: Value = serde_json::from_str(json_models.as_str())
-        .map_err(|_| NotificationData::IncorrectAnkiFile)?;
+        .map_err(|_| IncorrectAnkiFile)?;
     let sets = raw.as_object();
     if let Some(sets) = sets {
         let mut total_data = ImportData(vec![]);
 
         let mut count_stmt = connection
             .prepare("select mid, count(id) from notes group by mid")
-            .map_err(|_| NotificationData::IncorrectAnkiFile)?;
+            .map_err(|_| IncorrectAnkiFile)?;
 
         let counts = count_stmt
             .query_map([], |row| Ok((row.get(0)?, row.get(1)?)))
-            .map_err(|_| NotificationData::IncorrectAnkiFile)?
+            .map_err(|_| IncorrectAnkiFile)?
             .filter_map(|x| x.ok())
             .collect::<Vec<(i64, i64)>>();
 
         for (_, collection) in sets {
             let fields_property = collection.get("fields");
             if let Some(fields_property) = fields_property {
-                let fields = fields_property
+                let fields = into_result(fields_property
-                    .as_array()
+                    .as_array(), IncorrectAnkiFile)?
-                    .unwrap()
                     .iter()
                     .filter_map(|x| x.get("name"))
                     .map(|x| x.as_str().unwrap().to_string())
                     .collect();
                 let id = collection.get("id");
                 if id.is_none() || id.unwrap().as_u64().is_none(){
-                    return Err(NotificationData::IncorrectAnkiFile);
+                    return Err(IncorrectAnkiFile);
                 }
                 let id = id.unwrap().as_u64().unwrap();
                 let name = collection.get("name");
                 if name.is_none() || name.unwrap().as_str().is_none() {
-                    return Err(NotificationData::IncorrectAnkiFile);
+                    return Err(IncorrectAnkiFile);
                 }
                 let name = name.unwrap().as_str().unwrap().to_string();
 
@@ -81,13 +82,13 @@ pub fn load_groups(connection: &Connection) -> Result<ImportData, NotificationDa
         }
         return Ok(total_data)
     }
-    Err(NotificationData::IncorrectAnkiFile)
+    Err(IncorrectAnkiFile)
 }
 
 pub fn get_words_of_group(connection: &Connection, group_id: u64) -> Result<Vec<ImportNote>, NotificationData> {
     let mut count_stmt = connection
         .prepare("select tags, flds from notes where mid == ?1;")
-        .map_err(|_| NotificationData::IncorrectAnkiFile)?;
+        .map_err(|_| IncorrectAnkiFile)?;
 
     Ok(count_stmt
         .query_map((group_id as i64,), |row| {
@@ -100,7 +101,7 @@ pub fn get_words_of_group(connection: &Connection, group_id: u64) -> Result<Vec<
                     .collect(),
             })
         })
-        .map_err(|_| NotificationData::IncorrectAnkiFile)?
+        .map_err(|_| IncorrectAnkiFile)?
         .filter_map(|x| x.ok())
         .collect::<Vec<ImportNote>>())
 }

src/data_provider/settings.rs

@@ -1,4 +1,4 @@
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::notification::NotificationData::{DbLoadError, DbSaveError};
 use iced::futures::StreamExt;
 use rusqlite::Connection;
@@ -22,7 +22,7 @@ pub fn set_setting(
     key: String,
     value: String,
     connection: &Connection,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     let current = get_settings_list(connection)?;
     if current.contains(&key) {
         update_settings(key, value, connection)?;
@@ -33,7 +33,7 @@ pub fn set_setting(
     Ok(())
 }
 
-pub fn delete_settings(key: String, connection: &Connection) -> Result<(), NotificationData> {
+pub fn delete_settings(key: String, connection: &Connection) -> MaybeError {
     connection
         .execute("DELETE FROM settings WHERE id = ?1", (&key,))
         .map_err(|_| DbSaveError)?;
@@ -44,7 +44,7 @@ fn create_settings(
     key: String,
     value: String,
     connection: &Connection,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     connection
         .execute(
             "INSERT into settings (id, value) VALUES (?1, ?2)",
@@ -58,7 +58,7 @@ fn update_settings(
     key: String,
     value: String,
     connection: &Connection,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     connection
         .execute(
             "update settings

src/data_provider/sqlite.rs

@@ -5,19 +5,19 @@ pub fn create_db() {
     let db_file = db_path();
     if !db_file.exists() {
         std::fs::File::create(&db_file).expect("Database file creation failed");
-        let connection = Connection::open(&db_file).unwrap();
+        let connection = Connection::open(&db_file).expect("Connection open failed");
-        connection.execute("PRAGMA foreign_keys = ON;", []).unwrap();
+        connection.execute("PRAGMA foreign_keys = ON;", []).expect("Failed to set PRAGMA");
 
         create_tables(&connection);
     }
 }
 
 fn create_tables(conn: &Connection) {
-    make_card_set(conn).unwrap();
+    make_card_set(conn).expect("Failed to init table");
-    make_settings(conn).unwrap();
+    make_settings(conn).expect("Failed to init table");
-    make_word_group(conn).unwrap();
+    make_word_group(conn).expect("Failed to init table");
-    make_words(conn).unwrap();
+    make_words(conn).expect("Failed to init table");
-    make_card_stats(conn).unwrap();
+    make_card_stats(conn).expect("Failed to init table");
 }
 
 fn make_settings(conn: &Connection) -> Result<(), rusqlite::Error> {
@@ -51,7 +51,7 @@ fn make_card_stats(conn: &Connection) -> Result<(), rusqlite::Error> {
 
 pub fn default_connection() -> Connection {
     let db_file = db_path();
-    let connection = Connection::open(db_file).unwrap();
+    let connection = Connection::open(db_file).expect("Failed to open database");
-    connection.execute("PRAGMA foreign_keys = ON;", []).unwrap();
+    connection.execute("PRAGMA foreign_keys = ON;", []).expect("Failed to set PRAGMA");
     connection
 }

src/data_provider/web_api.rs

@@ -1,18 +1,20 @@
-use std::io;
+use crate::fs::*;
+use crate::notification::NotificationData::{CompressError, PermissionDenied, WebApiUnavailable};
+use crate::notification::{MaybeError, NotificationData};
 use log::info;
+use std::io;
 use tokio::fs::{File, OpenOptions};
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
-use zstd::{DEFAULT_COMPRESSION_LEVEL, Decoder, Encoder};
+use zstd::{Decoder, Encoder, DEFAULT_COMPRESSION_LEVEL};
-use crate::fs::*;
-use crate::notification::NotificationData;
-use crate::notification::NotificationData::{CompressError, PermissionDenied, WebApiUnavailable};
 
 // const API_URL: &str = "http://127.0.0.1:8089/";
 const API_URL: &str = "https://learning.micialware.ru/";
 
-pub async fn send_data(id: String) -> Result<(), NotificationData> {
+pub async fn send_data(id: String) -> MaybeError {
     let db_file = db_path();
-    let data = tokio::fs::read(db_file).await.map_err(|_| WebApiUnavailable)?;
+    let data = tokio::fs::read(db_file)
+        .await
+        .map_err(|_| WebApiUnavailable)?;
     let data = compress(data)?;
 
     let api_url = API_URL.to_string();
@@ -23,30 +25,35 @@ pub async fn send_data(id: String) -> Result<(), NotificationData> {
         .post(&id_url)
         .body(data)
         .send()
-        .await.map_err(|_| WebApiUnavailable)?
+        .await
+        .map_err(|_| WebApiUnavailable)?
         .text()
-        .await.map_err(|_| WebApiUnavailable)?;
+        .await
+        .map_err(|_| WebApiUnavailable)?;
     set_local_version(new_version.parse::<u32>().unwrap_or_default()).await;
     Ok(())
 }
 
 fn compress(data: Vec<u8>) -> Result<Vec<u8>, NotificationData> {
-    let mut encoder = Encoder::new(Vec::new(), DEFAULT_COMPRESSION_LEVEL).map_err(|_| CompressError)?;
+    let mut encoder =
+        Encoder::new(Vec::new(), DEFAULT_COMPRESSION_LEVEL).map_err(|_| CompressError)?;
     io::copy(&mut &data[..], &mut encoder).map_err(|_| PermissionDenied)?;
     encoder.finish().map_err(|_| CompressError)?;
     Ok(data)
 }
 
-pub async fn load_data(id: String, temp: bool) -> Result<(), NotificationData> {
+pub async fn load_data(id: String, temp: bool) -> MaybeError {
     let api_url = API_URL.to_string();
     let id_url = format!("{api_url}download/{id}");
     let client = reqwest::Client::new();
     let data = client
         .get(&id_url)
         .send()
-        .await.map_err(|_| WebApiUnavailable)?
+        .await
+        .map_err(|_| WebApiUnavailable)?
         .bytes()
-        .await.map_err(|_| WebApiUnavailable)?
+        .await
+        .map_err(|_| WebApiUnavailable)?
         .to_vec();
     let data = decompress(data)?;
 
@@ -54,15 +61,19 @@ pub async fn load_data(id: String, temp: bool) -> Result<(), NotificationData> {
     let file_name = if temp { "data.db.tmp" } else { "data.db" };
     let db_file = path.join(file_name);
 
-    tokio::fs::write(db_file, data).await.map_err(|_| PermissionDenied)?;
+    tokio::fs::write(db_file, data)
+        .await
+        .map_err(|_| PermissionDenied)?;
 
     let version_url = format!("{API_URL}{id}/version");
     let version = client
         .get(&version_url)
         .send()
-        .await.map_err(|_| WebApiUnavailable)?
+        .await
+        .map_err(|_| WebApiUnavailable)?
         .text()
-        .await.map_err(|_| WebApiUnavailable)?;
+        .await
+        .map_err(|_| WebApiUnavailable)?;
     set_local_version(version.parse::<u32>().unwrap_or_default()).await;
     Ok(())
 }
@@ -93,22 +104,29 @@ pub async fn first_sync() -> Result<String, NotificationData> {
 pub async fn get_web_version(key: &str) -> Result<u32, NotificationData> {
     let id_url = format!("{API_URL}{key}/version");
     let client = reqwest::Client::new();
-    let version = client.get(&id_url).send().await.map_err(|_| WebApiUnavailable)?.text().await.map_err(|_| WebApiUnavailable)?;
+    let version = client
+        .get(&id_url)
+        .send()
+        .await
+        .map_err(|_| WebApiUnavailable)?
+        .text()
+        .await
+        .map_err(|_| WebApiUnavailable)?;
     info!("version: {}", version);
     Ok(version.parse::<u32>().unwrap_or_default())
 }
 
-pub async fn get_local_version() -> u32 {
+pub async fn get_local_version() -> Result<u32, NotificationData> {
     let file = db_meta_path();
     if file.exists() {
         let mut data = String::new();
         File::open(file.clone())
             .await
-            .unwrap()
+            .map_err(|_| PermissionDenied)?
             .read_to_string(&mut data)
             .await
-            .unwrap();
+            .map_err(|_| PermissionDenied)?;
-        return data.parse::<u32>().unwrap_or_default();
+        return Ok(data.parse::<u32>().unwrap_or_default());
     }
 
     let mut file = OpenOptions::new()
@@ -117,12 +135,14 @@ pub async fn get_local_version() -> u32 {
         .truncate(true)
         .open(file)
         .await
-        .unwrap();
+        .map_err(|_| PermissionDenied)?;
-    file.write_all("0".as_bytes()).await.unwrap();
+    file.write_all("0".as_bytes())
-    0
+        .await
+        .map_err(|_| PermissionDenied)?;
+    Ok(0)
 }
 
-pub async fn set_local_version(version: u32) {
+pub async fn set_local_version(version: u32) -> Result<(), NotificationData> {
     let file_path = db_meta_path();
     let mut file = OpenOptions::new()
         .write(true)
@@ -130,8 +150,9 @@ pub async fn set_local_version(version: u32) {
         .truncate(true)
         .open(file_path)
         .await
-        .unwrap();
+        .map_err(|_| PermissionDenied)?;
     file.write_all(version.to_string().as_bytes())
         .await
-        .unwrap();
+        .map_err(|_| PermissionDenied)?;
+    Ok(())
 }

src/data_provider/words.rs

@@ -1,10 +1,10 @@
 use crate::data::entities::{WordData, WordGroup};
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::notification::NotificationData::{DbLoadError, DbSaveError};
 use rusqlite::{Connection, params};
 use std::collections::HashMap;
 
-pub fn add_word(word: &mut WordData, connection: &Connection) -> Result<(), NotificationData> {
+pub fn add_word(word: &mut WordData, connection: &Connection) -> MaybeError {
     let index : u32 = connection
         .query_row(
             "INSERT INTO words (key, value, tags, more, group_id) VALUES (?1, ?2, ?3, ?4, ?5) RETURNING id",
@@ -25,7 +25,7 @@ pub fn add_word(word: &mut WordData, connection: &Connection) -> Result<(), Noti
 pub fn add_words(
     words: &mut [WordData],
     connection: &mut Connection,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     let tx = connection.transaction().map_err(|_| DbLoadError)?;
     let count = words.len();
 
@@ -60,7 +60,7 @@ pub fn add_words(
     Ok(())
 }
 
-pub fn update_word(word: &mut WordData, connection: &Connection) -> Result<(), NotificationData> {
+pub fn update_word(word: &mut WordData, connection: &Connection) -> MaybeError {
     if !word.id.is_valid() {
         Ok(add_word(word, connection)?)
     } else {
@@ -71,7 +71,7 @@ pub fn update_word(word: &mut WordData, connection: &Connection) -> Result<(), N
                     &word.key,
                     &word.value,
                     &word.tags,
-                    serde_json::to_string(&word.additional).unwrap(),
+                    serde_json::to_string(&word.additional).map_err(|_| DbSaveError)?,
                     &word.id,
                 ),
             )
@@ -80,7 +80,7 @@ pub fn update_word(word: &mut WordData, connection: &Connection) -> Result<(), N
     }
 }
 
-pub fn delete_word(word: &WordData, connection: &Connection) -> Result<(), NotificationData> {
+pub fn delete_word(word: &WordData, connection: &Connection) -> MaybeError {
     if !word.id.is_valid() {
         return Err(DbSaveError);
     }
@@ -133,7 +133,7 @@ pub fn load_word_groups(connection: &Connection) -> Result<Vec<WordGroup>, Notif
     Ok(buffer)
 }
 
-pub fn add_group(group: &mut WordGroup, connection: &Connection) -> Result<(), NotificationData> {
+pub fn add_group(group: &mut WordGroup, connection: &Connection) -> MaybeError {
     let index: u32 = connection
         .query_row(
             "INSERT INTO word_group (name) VALUES (?1) RETURNING id",
@@ -149,7 +149,7 @@ pub fn add_group(group: &mut WordGroup, connection: &Connection) -> Result<(), N
 pub fn update_group(
     group: &mut WordGroup,
     connection: &Connection,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     if !group.id.is_valid() {
         Ok(add_group(group, connection)?)
     } else {
@@ -163,7 +163,7 @@ pub fn update_group(
     }
 }
 
-pub fn delete_group(group: &WordGroup, connection: &Connection) -> Result<(), NotificationData> {
+pub fn delete_group(group: &WordGroup, connection: &Connection) -> MaybeError {
     if !group.id.is_valid() {
         return Err(DbSaveError);
     }

src/helpers.rs

@@ -10,4 +10,14 @@ macro_rules! push_error {
     ($e:expr) => {
         $crate::navigation::RootMessage::PushNotification($crate::notification::NotificationRequest::Error($e))
     }
+}
+
+#[inline(always)]
+pub fn into_result<R, E>(option: Option<R>, error: E) -> Result<R, E>{
+    if let Some(r) = option {
+        Ok(r)
+    }
+    else {
+        Err(error)
+    }
 }

src/navigation.rs

@@ -172,7 +172,7 @@ impl ScreenState {
     }
 
     async fn load_web_backup(string: String) -> Result<bool, NotificationData> {
-        let local = get_local_version().await;
+        let local = get_local_version().await?;
         let web = get_web_version(string.as_str()).await?;
         info!("{} {}", local, web);
         if web > local {

src/notification.rs

@@ -192,3 +192,5 @@ pub enum NotificationData {
     DbLoadError,
     CompressError,
 }
+
+pub type MaybeError = Result<(), NotificationData>;

src/pages/import.rs

@@ -4,7 +4,7 @@ use crate::pages::import::ImportMessage::*;
 use crate::data::entities::{WordData, WordGroup};
 use crate::navigation::{NavigatedPage, Page, RootMessage};
 use crate::notification::NotificationData::OpenFileError;
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::styling::*;
 use iced::widget::button::danger;
 use iced::widget::container::success;
@@ -373,7 +373,7 @@ impl ImportState {
         )
     }
 
-    fn extract_import_file(path: PathBuf) -> Result<(), NotificationData> {
+    fn extract_import_file(path: PathBuf) -> MaybeError {
         let file = File::open(path).map_err(|_| OpenFileError)?;
         let reader = BufReader::new(file);
         let mut archive = ZipArchive::new(reader).map_err(|_| OpenFileError)?;

src/pages/repetition.rs

@@ -6,7 +6,7 @@ use crate::data::entities::{CardStatistics, DeckSettings, WordData};
 use crate::data_provider::voice::get_voice;
 use crate::navigation::Page::PreviousPage;
 use crate::navigation::{KeyPressedPage, NavigatedPage, Page, RootMessage};
-use crate::notification::NotificationData;
+use crate::notification::{MaybeError, NotificationData};
 use crate::styling::*;
 use crate::{push_error, push_error_task};
 use chrono::Local;
@@ -337,7 +337,7 @@ pub enum RepetitionMessage {
 async fn play_sound(
     sink: Arc<Option<MixerDeviceSink>>,
     text: String,
-) -> Result<(), NotificationData> {
+) -> MaybeError {
     let data = get_voice(text.as_str()).await?;
     spawn_blocking(move || {
         if let Some(sink) = sink.as_ref()
@@ -347,6 +347,6 @@ async fn play_sound(
         }
     })
     .await
-    .unwrap();
+    .expect("Playing sound failed");
     Ok(())
 }

src/pages/repetition_settings.rs

@@ -4,7 +4,7 @@ use crate::data_provider::card_sets::{delete_set, update_deck};
 use crate::data_provider::card_stats::{delete_stats, load_stats_of_deck};
 use crate::navigation::Page::PreviousPage;
 use crate::navigation::{NavigatedPage, Page, RootMessage};
-use crate::notification::NotificationData;
+use crate::notification::MaybeError;
 use crate::pages::repetition_settings::RepetitionSettingsMessage::*;
 use crate::styling::*;
 use crate::{push_error, push_error_task};
@@ -13,7 +13,7 @@ use iced::widget::text_input::Catalog;
 use iced::widget::{button, column, row, scrollable, space, text, text_input};
 use iced::{Element, Task};
 use iced_core::Length::Fill;
-use iced_core::{Padding, Theme, color};
+use iced_core::{color, Padding, Theme};
 use parking_lot::Mutex;
 use std::sync::Arc;
 use std::time::Duration;
@@ -179,7 +179,7 @@ impl NavigatedPage<RepetitionSettingsMessage> for RepetitionSettingsState {
     }
 }
 
-fn update_deck_stats(deck: &DeckSettings, state: &AppState) -> Result<(), NotificationData> {
+fn update_deck_stats(deck: &DeckSettings, state: &AppState) -> MaybeError {
     let mut db_stats = load_stats_of_deck(deck, &state.connection).expect("Wrong db operation");
     let filtered_words = deck.get_word_list(state);
     filtered_words.iter().for_each(|word| {

src/pages/repetitions.rs

@@ -1,12 +1,12 @@
 use crate::app::AppState;
 use crate::core::srs::{AppendMode, OrderMode};
-use crate::data::Id;
 use crate::data::entities::{CardStatistics, DeckSettings};
+use crate::data::Id;
 use crate::data_provider::card_sets::update_deck;
 use crate::data_provider::card_stats::{add_stat_list, load_stats_of_deck};
 use crate::navigation::Page::{History, PreviousPage, Repetition, RepetitionSettings};
 use crate::navigation::{NavigatedPage, Page, RootMessage};
-use crate::notification::{NotificationData, NotificationRequest};
+use crate::notification::{MaybeError, NotificationRequest};
 use crate::pages::history::HistoryState;
 use crate::pages::repetition::RepetitionState;
 use crate::pages::repetition_settings::RepetitionSettingsState;
@@ -16,17 +16,17 @@ use crate::push_error_task;
 use crate::styling::*;
 use chrono::{Days, Local, Utc};
 use hashbrown::{HashMap, HashSet};
+use iced::widget::button::{danger, Status};
 pub use iced::widget::button::{Catalog, Style};
-use iced::widget::button::{Status, danger};
 use iced::widget::tooltip::Position::Top;
 use iced::widget::{
-    Column, Row, button, column, container, lazy, radio, row, scrollable, space, svg, text,
+    button, column, container, lazy, radio, row, scrollable, space, svg, text, text_input, tooltip,
-    text_input, tooltip,
+    Column, Row,
 };
 use iced::{Background, Border, Center, Color, Element, Fill, Length, Shadow, Task, Theme};
-use iced_core::Padding;
 use iced_core::border::Radius;
 use iced_core::svg::Handle;
+use iced_core::Padding;
 use parking_lot::Mutex;
 use std::ops::Deref;
 use std::sync::Arc;
@@ -562,7 +562,7 @@ impl RepetitionsState {
 }
 
 impl RepetitionsState {
-    fn append_all_words(state: &mut AppState, deck: &DeckViewData) -> Result<(), NotificationData> {
+    fn append_all_words(state: &mut AppState, deck: &DeckViewData) -> MaybeError {
         let existing = &deck.existing_words_indices;
         let mut created_set = HashSet::with_capacity(existing.len());
         existing.iter().for_each(|c| {
@@ -580,7 +580,7 @@ impl RepetitionsState {
         state: &mut AppState,
         deck: &DeckSettings,
         indices: impl Iterator<Item = usize>,
-    ) -> Result<(), NotificationData> {
+    ) -> MaybeError {
         let words = &state.dictionary;
         let stats = &mut indices
             .map(|i| {
@@ -618,7 +618,7 @@ impl RepetitionsState {
         self.selected_deck_index = None;
     }
 
-    fn fill_deck_word_indices(&mut self) -> Result<(), NotificationData> {
+    fn fill_deck_word_indices(&mut self) -> MaybeError {
         let state = &self.state.lock();
         let mut deck = self.selected_deck().unwrap().clone();
         let added: Vec<_> = load_stats_of_deck(&deck, &state.connection)?