lindera_dictionary/

dictionary.rs

pub mod character_definition;
pub mod connection_cost_matrix;
pub mod metadata;
pub mod prefix_dictionary;
pub mod schema;
pub mod unknown_dictionary;

use std::fs;
use std::path::Path;
use std::str;

use byteorder::{ByteOrder, LittleEndian};
use once_cell::sync::Lazy;
use serde::{Deserialize, Serialize};

use crate::LinderaResult;
use crate::dictionary::character_definition::CharacterDefinition;
use crate::dictionary::connection_cost_matrix::ConnectionCostMatrix;
use crate::dictionary::metadata::Metadata;
use crate::dictionary::prefix_dictionary::PrefixDictionary;
use crate::dictionary::unknown_dictionary::UnknownDictionary;
use crate::dictionary_loader::character_definition::CharacterDefinitionLoader;
use crate::dictionary_loader::connection_cost_matrix::ConnectionCostMatrixLoader;
use crate::dictionary_loader::metadata::MetadataLoader;
use crate::dictionary_loader::prefix_dictionary::PrefixDictionaryLoader;
use crate::dictionary_loader::unknown_dictionary::UnknownDictionaryLoader;
use crate::error::LinderaErrorKind;

pub static UNK: Lazy<Vec<&str>> = Lazy::new(|| vec!["UNK"]);

#[derive(Clone)]
pub struct Dictionary {
    pub prefix_dictionary: PrefixDictionary,
    pub connection_cost_matrix: ConnectionCostMatrix,
    pub character_definition: CharacterDefinition,
    pub unknown_dictionary: UnknownDictionary,
    pub metadata: Metadata,
}

impl Dictionary {
    pub fn word_details(&self, word_id: usize) -> Vec<&str> {
        if 4 * word_id >= self.prefix_dictionary.words_idx_data.len() {
            return vec![];
        }

        let idx: usize = match LittleEndian::read_u32(
            &self.prefix_dictionary.words_idx_data[4 * word_id..][..4],
        )
        .try_into()
        {
            Ok(value) => value,
            Err(_) => return UNK.to_vec(), // return empty vector if conversion fails
        };
        let data = &self.prefix_dictionary.words_data[idx..];
        let joined_details_len: usize = match LittleEndian::read_u32(data).try_into() {
            Ok(value) => value,
            Err(_) => return UNK.to_vec(), // return empty vector if conversion fails
        };
        let joined_details_bytes: &[u8] =
            &self.prefix_dictionary.words_data[idx + 4..idx + 4 + joined_details_len];

        let mut details = Vec::new();
        for bytes in joined_details_bytes.split(|&b| b == 0) {
            let detail = match str::from_utf8(bytes) {
                Ok(s) => s,
                Err(_) => return UNK.to_vec(), // return empty vector if conversion fails
            };
            details.push(detail);
        }
        details
    }

    /// Load dictionary from a directory containing dictionary files
    pub fn load_from_path(dict_path: &Path) -> LinderaResult<Self> {
        Self::load_from_path_with_options(dict_path, false)
    }

    /// Load dictionary from a directory with options
    pub fn load_from_path_with_options(dict_path: &Path, use_mmap: bool) -> LinderaResult<Self> {
        // Verify that the dictionary directory exists
        if !dict_path.exists() {
            return Err(LinderaErrorKind::Io.with_error(anyhow::anyhow!(
                "Dictionary path does not exist: {}",
                dict_path.display()
            )));
        }

        if !dict_path.is_dir() {
            return Err(LinderaErrorKind::Io.with_error(anyhow::anyhow!(
                "Dictionary path is not a directory: {}",
                dict_path.display()
            )));
        }

        // Load each component from the dictionary directory
        let metadata = MetadataLoader::load(dict_path)?;
        let character_definition = CharacterDefinitionLoader::load(dict_path)?;

        let connection_cost_matrix = {
            #[cfg(feature = "mmap")]
            if use_mmap {
                ConnectionCostMatrixLoader::load_mmap(dict_path)?
            } else {
                ConnectionCostMatrixLoader::load(dict_path)?
            }
            #[cfg(not(feature = "mmap"))]
            ConnectionCostMatrixLoader::load(dict_path)?
        };

        let prefix_dictionary = {
            #[cfg(feature = "mmap")]
            if use_mmap {
                PrefixDictionaryLoader::load_mmap(dict_path)?
            } else {
                PrefixDictionaryLoader::load(dict_path)?
            }
            #[cfg(not(feature = "mmap"))]
            PrefixDictionaryLoader::load(dict_path)?
        };

        let unknown_dictionary = UnknownDictionaryLoader::load(dict_path)?;

        Ok(Dictionary {
            prefix_dictionary,
            connection_cost_matrix,
            character_definition,
            unknown_dictionary,
            metadata,
        })
    }

    /// Save dictionary to a directory
    pub fn save_to_path(&self, dict_path: &Path) -> LinderaResult<()> {
        // Create directory if it doesn't exist
        fs::create_dir_all(dict_path)
            .map_err(|err| LinderaErrorKind::Io.with_error(anyhow::anyhow!(err)))?;

        // For now, we'll implement this as needed
        // This would require implementing save methods for each component
        todo!("Dictionary saving will be implemented when needed")
    }
}

#[derive(Clone, Serialize, Deserialize)]
pub struct UserDictionary {
    pub dict: PrefixDictionary,
}

impl UserDictionary {
    pub fn load(user_dict_data: &[u8]) -> LinderaResult<UserDictionary> {
        bincode::serde::decode_from_slice(user_dict_data, bincode::config::legacy())
            .map(|(result, _len)| result)
            .map_err(|err| LinderaErrorKind::Deserialize.with_error(anyhow::anyhow!(err)))
    }

    pub fn word_details(&self, word_id: usize) -> Vec<&str> {
        if 4 * word_id >= self.dict.words_idx_data.len() {
            return UNK.to_vec(); // return empty vector if conversion fails
        }
        let idx = LittleEndian::read_u32(&self.dict.words_idx_data[4 * word_id..][..4]);
        let data = &self.dict.words_data[idx as usize..];

        // Parse the data in the same format as main Dictionary
        let joined_details_len: usize = match LittleEndian::read_u32(data).try_into() {
            Ok(value) => value,
            Err(_) => return UNK.to_vec(), // return empty vector if conversion fails
        };
        let joined_details_bytes: &[u8] =
            &self.dict.words_data[idx as usize + 4..idx as usize + 4 + joined_details_len];

        let mut details = Vec::new();
        for bytes in joined_details_bytes.split(|&b| b == 0) {
            let detail = match str::from_utf8(bytes) {
                Ok(s) => s,
                Err(_) => return UNK.to_vec(), // return empty vector if conversion fails
            };
            details.push(detail);
        }
        details
    }
}