Struct MonolingualDictionaryService 

pub struct MonolingualDictionaryService {
    client: MonolingualClient,
    db: Db,
    dict_dir: PathBuf,
    pending_installs: Arc<Mutex<HashSet<String>>>,
}

Provides monolingual dictionary management: querying available dictionaries, listing installed ones, and downloading + extracting new ones.

All network metadata is cached in the application SQLite database. Downloaded dictionaries are extracted to <dict_dir>/reader-dict/<lang>/.

The service is cheaply cloneable (Arc-backed). All clones share the same pending_installs set, so concurrent-download guards work correctly across the UI thread (which holds the original) and background threads (which hold clones).

Fields

client: MonolingualClient

db: Db

dict_dir: PathBuf

pending_installs: Arc<Mutex<HashSet<String>>>

Implementations

impl MonolingualDictionaryService

pub fn new( database: &Database, dict_dir: &Path, ) -> Result<Self, MonolingualError>

Creates a new service.

Arguments

• database - Application SQLite database used for metadata caching.
• dict_dir - Root directory where dictionaries are stored. Downloads are placed in <dict_dir>/reader-dict/<lang>/.

Errors

Returns an error if the HTTP client cannot be built.

pub fn get_available_dictionaries( &self, ) -> Result<Vec<(String, DictionaryEntry)>, MonolingualError>

Returns all dictionaries available for download from the remote API.

Metadata is served from the SQLite cache when available; otherwise a network request is made and the result is cached.

Errors

Returns an error if the metadata cannot be loaded from cache or network.

pub fn get_entry_for_lang( &self, lang: &str, ) -> Result<Option<DictionaryEntry>, MonolingualError>

Returns the cached metadata entry for a single language.

This does not make any network requests. Returns None if no entry for lang has been cached yet.

Errors

Returns an error if the database read fails.

pub fn get_installed_dictionaries( &self, ) -> Result<Vec<String>, MonolingualError>

Returns the language codes of all locally installed dictionaries.

A dictionary is considered installed when its language directory exists inside <dict_dir>/reader-dict/ and contains at least one .index file paired with a .dict or .dict.dz file.

Errors

Returns an error if the directory cannot be read.

pub fn is_installing(&self, lang: &str) -> bool

Returns true if a download is already in progress for lang.

This can be used by callers to suppress duplicate install requests before spawning a background thread.

pub fn install_dictionary<F>( &self, lang: &str, entry: &DictionaryEntry, include_etymologies: bool, progress_callback: &mut F, ) -> Result<(), MonolingualError>

where F: FnMut(u64, u64),

Downloads and installs a dictionary for the given language.

The archive is downloaded to a temporary file, then extracted into <dict_dir>/reader-dict/<lang>/ and the files are renamed to Reader-Dict-<lang>.index and Reader-Dict-<lang>.dict[.dz]. Any existing files in that directory are overwritten.

Returns MonolingualError::InstallationInProgress immediately if a download for the same language is already running. The caller should check Self::is_installing on the UI thread before spawning a thread to get a user-visible early exit; this check inside install_dictionary provides a safety net against races.

Arguments

• entry - Metadata entry for the dictionary to install. The language code and version are derived from this entry.
• include_etymologies - When true, the full archive (with etymologies) is downloaded; when false, the smaller no-etymology variant is used.
• progress_callback - Called after each downloaded chunk with (bytes_downloaded_so_far, total_bytes).

Errors

Returns an error if a download for the language is already in progress, if the download fails, if the archive cannot be parsed, or if files cannot be written to disk.

fn do_install<F>( &self, lang: &str, entry: &DictionaryEntry, include_etymologies: bool, progress_callback: &mut F, ) -> Result<(), MonolingualError>

where F: FnMut(u64, u64),

pub fn remove_installed(&self, lang: &str)

Removes the installed dictionary record for lang from the database.

Logs a warning on failure rather than propagating the error, as this is a best-effort cleanup step called from event handlers.

pub fn is_update_available(&self, lang: &str) -> bool

Returns true if a newer version of the dictionary for lang is available on the server than the currently installed version.

Returns false on any error to avoid surfacing spurious update badges.

fn load_metadata( &self, ) -> Result<HashMap<String, HashMap<String, DictionaryEntry>>, MonolingualError>

fn fetch_and_cache_metadata( &self, ) -> Result<HashMap<String, HashMap<String, DictionaryEntry>>, MonolingualError>

fn get_cached_metadata( &self, ) -> Result<Option<HashMap<String, HashMap<String, DictionaryEntry>>>, MonolingualError>

fn reader_dict_dir(&self) -> PathBuf

fn lang_dir(&self, lang: &str) -> PathBuf

Trait Implementations

impl Clone for MonolingualDictionaryService

fn clone(&self) -> MonolingualDictionaryService

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MonolingualDictionaryService

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.