// SPDX-License-Identifier: GPL-3.0-or-later
// src/document/store.rs
//
// RON-based persistence for session data: load and save session lists.
//
// For the session concept and the meaning of each field see `session.rs`.
//
// On disk a session file contains a RON list of SessionData records:
//
// [
//     (
//         name: "Pictures",
//         kind: DirectoryBrowser,
//         path: Some("/home/user/Pictures"),
//         items: [],
//         current_index: None,
//     ),
//     (
//         name: "Project Docs",
//         kind: DocumentCollection,
//         path: None,
//         items: [
//             (path: "/home/user/docs/spec.pdf",  page_index: 0),
//             (path: "/home/user/docs/notes.pdf", page_index: 2),
//         ],
//         current_index: Some(0),
//     ),
// ]

use crate::document::session::SessionData;
use crate::error::{Error, Result};
use std::path::Path;

/// Loads all sessions from a RON file.
pub fn load_sessions(path: &Path) -> Result<Vec<SessionData>> {
    let content = std::fs::read_to_string(path).map_err(Error::Io)?;

    ron::from_str(&content)
        .map_err(|e| Error::Session(format!("Failed to parse session file {:?}: {}", path, e)))
}

/// Saves all sessions to a RON file.
#[allow(dead_code)]
pub fn save_sessions(path: &Path, sessions: &[SessionData]) -> Result<()> {
    let content = ron::ser::to_string_pretty(sessions, ron::ser::PrettyConfig::default())
        .map_err(|e| Error::Session(format!("Failed to serialize sessions: {}", e)))?;

    std::fs::write(path, content).map_err(Error::Io)
}