//! TST is a space-optimized tree data structure that enables efficient string key operations
//! with persistent storage using OurDB as a backend.
//!
//! This implementation provides a persistent ternary search tree that can be used for efficient
//! string key operations, such as auto-complete, routing tables, and more.

mod error;
mod node;
mod operations;
mod serialize;

pub use error::Error;
pub use node::TSTNode;

use ourdb::OurDB;

/// TST represents a ternary search tree data structure with persistent storage.
pub struct TST {
    /// Database for persistent storage
    db: OurDB,
    
    /// Database ID of the root node
    root_id: Option<u32>,
}

impl TST {
    /// Creates a new TST with the specified database path.
    ///
    /// # Arguments
    ///
    /// * `path` - The path to the database directory
    /// * `reset` - Whether to reset the database if it exists
    ///
    /// # Returns
    ///
    /// A new `TST` instance
    ///
    /// # Errors
    ///
    /// Returns an error if the database cannot be created or opened
    pub fn new(path: &str, reset: bool) -> Result<Self, Error> {
        operations::new_tst(path, reset)
    }

    /// Sets a key-value pair in the tree.
    ///
    /// # Arguments
    ///
    /// * `key` - The key to set
    /// * `value` - The value to set
    ///
    /// # Errors
    ///
    /// Returns an error if the operation fails
    pub fn set(&mut self, key: &str, value: Vec<u8>) -> Result<(), Error> {
        operations::set(self, key, value)
    }

    /// Gets a value by key from the tree.
    ///
    /// # Arguments
    ///
    /// * `key` - The key to get
    ///
    /// # Returns
    ///
    /// The value associated with the key
    ///
    /// # Errors
    ///
    /// Returns an error if the key is not found or the operation fails
    pub fn get(&mut self, key: &str) -> Result<Vec<u8>, Error> {
        operations::get(self, key)
    }

    /// Deletes a key from the tree.
    ///
    /// # Arguments
    ///
    /// * `key` - The key to delete
    ///
    /// # Errors
    ///
    /// Returns an error if the key is not found or the operation fails
    pub fn delete(&mut self, key: &str) -> Result<(), Error> {
        operations::delete(self, key)
    }

    /// Lists all keys with a given prefix.
    ///
    /// # Arguments
    ///
    /// * `prefix` - The prefix to search for
    ///
    /// # Returns
    ///
    /// A list of keys that start with the given prefix
    ///
    /// # Errors
    ///
    /// Returns an error if the operation fails
    pub fn list(&mut self, prefix: &str) -> Result<Vec<String>, Error> {
        operations::list(self, prefix)
    }

    /// Gets all values for keys with a given prefix.
    ///
    /// # Arguments
    ///
    /// * `prefix` - The prefix to search for
    ///
    /// # Returns
    ///
    /// A list of values for keys that start with the given prefix
    ///
    /// # Errors
    ///
    /// Returns an error if the operation fails
    pub fn getall(&mut self, prefix: &str) -> Result<Vec<Vec<u8>>, Error> {
        operations::getall(self, prefix)
    }
}