// cli/journal.rs — journal subcommand handlers


pub fn cmd_tail(n: usize, full: bool, provenance: Option<&str>, dedup: bool) -> Result<(), String> {
    let path = crate::store::nodes_path();
    if !path.exists() {
        return Err("No node log found".into());
    }

    use std::io::BufReader;
    let file = std::fs::File::open(&path)
        .map_err(|e| format!("open {}: {}", path.display(), e))?;
    let mut reader = BufReader::new(file);

    // Read all entries, keep last N
    let mut entries: Vec<crate::store::Node> = Vec::new();
    while let Ok(msg) = capnp::serialize::read_message(&mut reader, capnp::message::ReaderOptions::new()) {
        let log = msg.get_root::<crate::memory_capnp::node_log::Reader>()
            .map_err(|e| format!("read log: {}", e))?;
        for node_reader in log.get_nodes()
            .map_err(|e| format!("get nodes: {}", e))? {
            let node = crate::store::Node::from_capnp_migrate(node_reader)?;
            entries.push(node);
        }
    }

    // Filter by provenance if specified (substring match)
    if let Some(prov) = provenance {
        entries.retain(|n| n.provenance.contains(prov));
    }

    // Dedup: keep only the latest version of each key
    if dedup {
        let mut seen = std::collections::HashSet::new();
        // Walk backwards so we keep the latest
        entries = entries.into_iter().rev()
            .filter(|n| seen.insert(n.key.clone()))
            .collect();
        entries.reverse();
    }

    let start = entries.len().saturating_sub(n);
    for node in &entries[start..] {
        let ts = if node.timestamp > 0 && node.timestamp < 4_000_000_000 {
            crate::store::format_datetime(node.timestamp)
        } else {
            format!("(raw:{})", node.timestamp)
        };
        let del = if node.deleted { " [DELETED]" } else { "" };
        if full {
            println!("--- {} (v{}) {} via {} w={:.3}{} ---",
                node.key, node.version, ts, node.provenance, node.weight, del);
            println!("{}\n", node.content);
        } else {
            let preview = crate::util::first_n_chars(&node.content, 100).replace('\n', "\\n");
            println!("  {}  v{}  w={:.2}{}",
                ts, node.version, node.weight, del);
            println!("  {}  via {}", node.key, node.provenance);
            if !preview.is_empty() {
                println!("  {}", preview);
            }
            println!();
        }
    }

    Ok(())
}

pub fn find_current_transcript() -> Option<String> {
    let projects = crate::config::get().projects_dir.clone();
    if !projects.exists() { return None; }

    let mut newest: Option<(std::time::SystemTime, std::path::PathBuf)> = None;
    if let Ok(dirs) = std::fs::read_dir(&projects) {
        for dir_entry in dirs.filter_map(|e| e.ok()) {
            if !dir_entry.path().is_dir() { continue; }
            if let Ok(files) = std::fs::read_dir(dir_entry.path()) {
                for f in files.filter_map(|e| e.ok()) {
                    let p = f.path();
                    if p.extension().map(|x| x == "jsonl").unwrap_or(false)
                        && let Ok(meta) = p.metadata()
                            && let Ok(mtime) = meta.modified()
                                && newest.as_ref().is_none_or(|(t, _)| mtime > *t) {
                                    newest = Some((mtime, p));
                                }
                }
            }
        }
    }
    newest.map(|(_, p)| p.to_string_lossy().to_string())
}

pub fn cmd_journal_tail(n: usize, full: bool, level: u8) -> Result<(), String> {
    let format = if full { "full" } else { "compact" };
    let result = crate::mcp_server::memory_rpc(
        "journal_tail",
        serde_json::json!({"count": n, "level": level, "format": format}),
    ).map_err(|e| e.to_string())?;
    print!("{}", result);
    Ok(())
}

pub fn cmd_journal_write(name: &str, text: &[String]) -> Result<(), String> {
    if text.is_empty() {
        return Err("journal write requires text".into());
    }
    super::check_dry_run();
    let text = text.join(" ");

    let timestamp = crate::store::format_datetime(crate::store::now_epoch());
    let content = format!("## {} — {}\n\n{}", timestamp, name, text);

    let key: String = name.split_whitespace()
        .map(|w| w.to_lowercase()
            .chars().filter(|c| c.is_alphanumeric() || *c == '-')
            .collect::<String>())
        .filter(|s| !s.is_empty())
        .collect::<Vec<_>>()
        .join("-");

    let source_ref = find_current_transcript();

    let mut store = crate::store::Store::load()?;

    let mut node = crate::store::new_node(&key, &content);
    node.node_type = crate::store::NodeType::EpisodicSession;
    node.provenance = "journal".to_string();
    if let Some(src) = source_ref {
        node.source_ref = src;
    }

    store.upsert_node(node)?;
    store.save()?;

    let word_count = text.split_whitespace().count();
    println!("Appended entry at {} ({} words)", timestamp, word_count);

    Ok(())
}