use std::env;
use std::hash::{Hash, Hasher};

use chrono::Utc;

use crate::command::uuid_v4;

// Any new fields MUST be Optional<>!
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct History {
    pub id: String,
    pub timestamp: chrono::DateTime<Utc>,
    pub duration: i64,
    pub exit: i64,
    pub command: String,
    pub cwd: String,
    pub session: String,
    pub hostname: String,
}

impl History {
    pub fn new(
        timestamp: chrono::DateTime<Utc>,
        command: String,
        cwd: String,
        exit: i64,
        duration: i64,
        session: Option<String>,
        hostname: Option<String>,
    ) -> Self {
        let session = session
            .or_else(|| env::var("ATUIN_SESSION").ok())
            .unwrap_or_else(uuid_v4);
        let hostname =
            hostname.unwrap_or_else(|| format!("{}:{}", whoami::hostname(), whoami::username()));

        Self {
            id: uuid_v4(),
            timestamp,
            command,
            cwd,
            exit,
            duration,
            session,
            hostname,
        }
    }
}

impl PartialEq for History {
    // for the sakes of listing unique history only, we do not care about
    // anything else
    // obviously this does not refer to the *same* item of history, but when
    // we only render the command, it looks the same
    fn eq(&self, other: &Self) -> bool {
        self.command == other.command
    }
}

impl Eq for History {}

impl Hash for History {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.command.hash(state);
    }
}