holdon 0.1.1

use std::time::Duration;

const MICROS_PER_SEC: f64 = 1_000_000.0;
const MICROS_PER_MS: f64 = 1_000.0;
const MICROS_PER_MIN: f64 = 60.0 * MICROS_PER_SEC;
const MICROS_PER_HOUR: f64 = 60.0 * MICROS_PER_MIN;
const MAX_F64_MICROS: f64 = 9_223_372_036_854_775_000.0;
const FMT_DUR_SECS_BOUNDARY_MS: u128 = 1_000;

/// Walks an error's source chain, joining each layer with `": "`, then runs
/// the result through [`sanitize_for_terminal`].
///
/// Pair with [`redact_in`] at the call site if the message could embed a
/// connection string or password.
#[must_use]
pub fn format_error_chain(err: &dyn std::error::Error) -> String {
    let mut out = err.to_string();
    let mut cur = err.source();
    while let Some(src) = cur {
        out.push_str(": ");
        out.push_str(&src.to_string());
        cur = src.source();
    }
    sanitize_for_terminal(&out)
}

/// Replaces control bytes that could otherwise be interpreted as terminal
/// escape sequences with `\u{fffd}`.
///
/// Tab and newline are preserved. Every other byte below `0x20` and DEL
/// (`0x7f`) is replaced. Blocks ANSI escape injection, carriage-return
/// overstrike, bell-spam, and OSC title-rewrite via attacker-controlled
/// error text.
#[must_use]
pub fn sanitize_for_terminal(s: &str) -> String {
    let mut out = String::with_capacity(s.len());
    for c in s.chars() {
        match c {
            '\t' | '\n' => out.push(c),
            c if (c as u32) < 0x20 || c == '\x7f' => out.push('\u{fffd}'),
            _ => out.push(c),
        }
    }
    out
}

/// Replaces every occurrence of `secret` in `text` with `***`.
///
/// Empty `secret` is a no-op.
#[must_use]
pub fn redact_in(text: &str, secret: &str) -> String {
    if secret.is_empty() {
        return text.to_owned();
    }
    text.replace(secret, "***")
}

/// Returns the duration in milliseconds, saturating at [`u64::MAX`].
#[must_use]
pub fn duration_ms(d: Duration) -> u64 {
    u64::try_from(d.as_millis()).unwrap_or(u64::MAX)
}

/// Renders a duration as a short human-readable string.
///
/// Sub-second durations render in milliseconds (`42ms`). Longer durations
/// render in seconds with one decimal (`1.5s`).
#[must_use]
pub fn fmt_dur(d: Duration) -> String {
    let ms = d.as_millis();
    if ms < FMT_DUR_SECS_BOUNDARY_MS {
        format!("{ms}ms")
    } else {
        format!("{:.1}s", d.as_secs_f64())
    }
}

/// Parses a duration string into a [`Duration`].
///
/// Accepted units: `us` / `µs`, `ms`, `s` (default if no unit), `m`, `h`.
/// Compound forms like `1h30m` are not accepted. A bare number is interpreted
/// as seconds for compatibility with `wait-for-it.sh`. Negative, NaN, and
/// infinite values are rejected.
///
/// # Errors
/// Returns a human-readable error string when the input is not a finite
/// non-negative number followed by a recognized unit.
pub fn parse_duration(s: &str) -> Result<Duration, String> {
    let s = s.trim();
    let (num, unit) = s
        .find(|c: char| !c.is_ascii_digit() && c != '.')
        .map_or((s, ""), |i| s.split_at(i));
    let n: f64 = num
        .parse()
        .map_err(|e| format!("invalid number `{num}`: {e}"))?;
    if !n.is_finite() || n < 0.0 {
        return Err(format!(
            "invalid duration `{s}`: must be finite and non-negative"
        ));
    }
    let mult_us: f64 = match unit.trim() {
        "" | "s" => MICROS_PER_SEC,
        "ms" => MICROS_PER_MS,
        "us" | "µs" => 1.0,
        "m" => MICROS_PER_MIN,
        "h" => MICROS_PER_HOUR,
        other => return Err(format!("unknown unit `{other}` (use ms, s, m, h)")),
    };
    #[allow(
        clippy::cast_sign_loss,
        clippy::cast_possible_truncation,
        clippy::cast_precision_loss
    )]
    let micros = (n * mult_us).clamp(0.0, MAX_F64_MICROS) as u64;
    Ok(Duration::from_micros(micros))
}

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

    #[test]
    fn parses_seconds_default() {
        assert_eq!(parse_duration("30").unwrap(), Duration::from_secs(30));
        assert_eq!(parse_duration("30s").unwrap(), Duration::from_secs(30));
    }

    #[test]
    fn parses_units() {
        assert_eq!(parse_duration("100ms").unwrap(), Duration::from_millis(100));
        assert_eq!(parse_duration("500us").unwrap(), Duration::from_micros(500));
        assert_eq!(parse_duration("1.5s").unwrap(), Duration::from_millis(1500));
        assert_eq!(parse_duration("2m").unwrap(), Duration::from_secs(120));
        assert_eq!(parse_duration("1h").unwrap(), Duration::from_secs(3600));
    }

    #[test]
    fn rejects_invalid() {
        assert!(parse_duration("inf").is_err());
        assert!(parse_duration("NaN").is_err());
        assert!(parse_duration("-5s").is_err());
        assert!(parse_duration("5x").is_err());
    }

    #[test]
    fn fmt_dur_human() {
        assert_eq!(fmt_dur(Duration::from_millis(42)), "42ms");
        assert_eq!(fmt_dur(Duration::from_millis(1500)), "1.5s");
    }

    #[test]
    fn sanitize_strips_escape_and_control() {
        let evil = "ok\x1b[31mred\x1b[0m\x07\rrest";
        let safe = sanitize_for_terminal(evil);
        assert!(!safe.contains('\x1b'));
        assert!(!safe.contains('\x07'));
        assert!(!safe.contains('\r'));
        assert!(safe.contains("ok"));
    }

    #[test]
    fn sanitize_keeps_tab_and_newline() {
        assert_eq!(sanitize_for_terminal("a\tb\nc"), "a\tb\nc");
    }

    #[test]
    fn redact_replaces_secret() {
        assert_eq!(redact_in("user:hunter2@host", "hunter2"), "user:***@host");
        assert_eq!(redact_in("none", ""), "none");
    }

    #[test]
    fn cli_defaults_match_runner_constants() {
        use crate::RunnerConfig;
        assert_eq!(
            parse_duration("30s").unwrap(),
            RunnerConfig::DEFAULT_OVERALL_TIMEOUT
        );
        assert_eq!(
            parse_duration("100ms").unwrap(),
            RunnerConfig::DEFAULT_INITIAL_INTERVAL
        );
        assert_eq!(
            parse_duration("2s").unwrap(),
            RunnerConfig::DEFAULT_MAX_INTERVAL
        );
        assert_eq!(
            parse_duration("0s").unwrap(),
            RunnerConfig::DEFAULT_INITIAL_DELAY
        );
        assert_eq!(
            parse_duration("5s").unwrap(),
            RunnerConfig::DEFAULT_ATTEMPT_TIMEOUT
        );
    }
}