use anyhow::Result;
use tracing::info;
use super::rcon::RconClient;

/// Player information from an ARK RCON `ListPlayers` response.
pub struct ArkPlayer {
    pub name: String,
    pub steamid: String,
}

/// Query an ARK server for its connected players.
pub async fn get_players(rcon_address: &str, rcon_password: &str) -> Result<Vec<ArkPlayer>> {
    let mut client = RconClient::connect(rcon_address, rcon_password).await?;
    let response = client.command("ListPlayers").await?;

    let players = parse_list_players_response(&response);
    info!(count = players.len(), "ARK player list retrieved");

    Ok(players)
}

/// Parses lines shaped like `0. PlayerName, 76561198000000000`.
fn parse_list_players_response(response: &str) -> Vec<ArkPlayer> {
    let mut players = Vec::new();

    for line in response.lines() {
        let trimmed = line.trim();
        if trimmed.is_empty() {
            continue;
        }

        // "No Players Connected"
        if trimmed.eq_ignore_ascii_case("no players connected") {
            break;
        }

        // Strip the "<index>. " prefix.
        let entry = match trimmed.split_once('.') {
            Some((index, rest)) if index.trim().chars().all(|c| c.is_ascii_digit()) => rest.trim(),
            _ => continue,
        };

        let (name, steamid) = match entry.rsplit_once(',') {
            Some((name, steamid)) => (name.trim(), steamid.trim()),
            None => (entry, ""),
        };

        if name.is_empty() {
            continue;
        }

        players.push(ArkPlayer {
            name: name.to_string(),
            steamid: steamid.to_string(),
        });
    }

    players
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn parses_connected_players() {
        let response = "0. Alper, 76561198000000001\n1. Rezan, 76561198000000002\n";
        let players = parse_list_players_response(response);

        assert_eq!(players.len(), 2);
        assert_eq!(players[0].name, "Alper");
        assert_eq!(players[0].steamid, "76561198000000001");
        assert_eq!(players[1].name, "Rezan");
    }

    #[test]
    fn handles_empty_server() {
        assert!(parse_list_players_response("No Players Connected\n").is_empty());
    }
}