agent-team-mail-core 1.0.1

use std::path::Path;

use crate::error::{AtmError, AtmErrorKind};
use crate::persistence;
use crate::schema::MessageEnvelope;

/// Atomically replace one mailbox JSONL file from fully serialized records.
///
/// ATM serializes every envelope into one temp file, fsyncs that temp file, and
/// then performs same-filesystem replacement through the shared persistence
/// helper. On Linux, a successful return means the file contents and renamed
/// directory entry were durably published after the parent-directory fsync. On
/// macOS, ATM performs the same parent-directory sync call, but APFS durability
/// semantics may still differ from Linux after power loss. On Windows, the
/// shared helper returns `Ok(())` after temp-file fsync plus rename without an
/// additional parent-directory sync because the standard library does not
/// expose a portable directory-sync operation there.
///
/// # Errors
///
/// Returns [`AtmError`] with
/// [`crate::error_codes::AtmErrorCode::MailboxWriteFailed`] when message
/// serialization fails or the mailbox temp-file write, fsync, rename, or
/// parent-directory durability step cannot be completed.
pub fn write_messages(path: &Path, messages: &[MessageEnvelope]) -> Result<(), AtmError> {
    let mut bytes = Vec::new();
    for message in messages {
        serde_json::to_writer(&mut bytes, message)?;
        bytes.push(b'\n');
    }

    persistence::atomic_write_bytes(
        path,
        &bytes,
        AtmErrorKind::MailboxWrite,
        "mailbox file",
        "Check that the mailbox directory is writable, has available disk space, and resides on a healthy filesystem before retrying the ATM command.",
    )
}