parlov 0.6.0

//! `ScanContext` construction and CLI argument parsing for the scan pipeline.
//!
//! Separated from `scan.rs` to keep module sizes under the 250-line ceiling.

use http::HeaderMap;
use parlov_core::Error;
use parlov_elicit::{KnownDuplicate, RiskLevel, ScanContext, StateField};

use crate::util::parse_headers;
use crate::vector_filter::{max_risk_from_filters, VectorFilter};

/// Parses a risk level string into a `RiskLevel`.
///
/// # Errors
///
/// Returns `Err` for any string other than `"safe"`, `"method-destructive"`,
/// or `"operation-destructive"`.
pub(crate) fn parse_risk(s: &str) -> Result<RiskLevel, Error> {
    match s {
        "safe" => Ok(RiskLevel::Safe),
        "method-destructive" => Ok(RiskLevel::MethodDestructive),
        "operation-destructive" => Ok(RiskLevel::OperationDestructive),
        other => Err(Error::Http(format!(
            "invalid risk level '{other}'; expected safe | method-destructive | operation-destructive"
        ))),
    }
}

/// Parses a `"field=value"` string into a `KnownDuplicate`.
///
/// Splits on the first `=` only; the value may itself contain `=`.
///
/// # Errors
///
/// Returns `Err` when the input contains no `=` character.
pub(crate) fn parse_known_duplicate(s: &str) -> Result<KnownDuplicate, Error> {
    let (field, value) = s.split_once('=').ok_or_else(|| {
        Error::Http(format!("known-duplicate must be 'field=value', got '{s}'"))
    })?;
    Ok(KnownDuplicate { field: field.to_owned(), value: value.to_owned() })
}

/// Parses a `"field=value"` string into a `StateField`.
///
/// Splits on the first `=` only; the value may itself contain `=`.
///
/// # Errors
///
/// Returns `Err` when the input contains no `=` character.
pub(crate) fn parse_state_field(s: &str) -> Result<StateField, Error> {
    let (field, value) = s.split_once('=').ok_or_else(|| {
        Error::Http(format!("state-field must be 'field=value', got '{s}'"))
    })?;
    Ok(StateField { field: field.to_owned(), value: value.to_owned() })
}

/// Parses an alt-credential header string `"Name: Value"` into a `HeaderMap`.
///
/// # Errors
///
/// Returns `Err` for malformed header strings.
pub(crate) fn parse_alt_credential(s: &str) -> Result<HeaderMap, Error> {
    parse_headers(&[s.to_owned()])
}

/// Constructs a `ScanContext` from CLI arguments.
///
/// When `--vector` flags are present, sets `max_risk` to the highest per-vector
/// ceiling so `generate_plan` produces a superset to be post-filtered.
pub(crate) fn build_scan_context(
    args: &crate::cli::ScanArgs,
    vector_filters: &[VectorFilter],
) -> Result<ScanContext, Error> {
    let probe_id = args
        .probe_id
        .clone()
        .unwrap_or_else(|| uuid::Uuid::new_v4().to_string());

    let max_risk = if vector_filters.is_empty() {
        parse_risk(&args.risk)?
    } else {
        max_risk_from_filters(vector_filters)
    };
    let headers = parse_headers(&args.headers)?;

    let known_duplicate = args
        .known_duplicate
        .as_deref()
        .map(parse_known_duplicate)
        .transpose()?;

    let state_field = args.state_field.as_deref().map(parse_state_field).transpose()?;

    let alt_credential = args
        .alt_credential
        .as_deref()
        .map(parse_alt_credential)
        .transpose()?;

    Ok(ScanContext {
        target: args.target.clone(),
        baseline_id: args.baseline_id.clone(),
        probe_id,
        headers,
        max_risk,
        known_duplicate,
        state_field,
        alt_credential,
        body_template: args.body.clone(),
    })
}

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

    fn minimal_args(target: &str, baseline_id: &str) -> ScanArgs {
        ScanArgs {
            target: target.to_owned(),
            baseline_id: baseline_id.to_owned(),
            probe_id: Some("9999".to_owned()),
            risk: "safe".to_owned(),
            headers: vec![],
            alt_credential: None,
            known_duplicate: None,
            state_field: None,
            vectors: vec![],
            body: None,
        }
    }

    #[test]
    fn parse_risk_safe() {
        assert_eq!(parse_risk("safe").unwrap(), RiskLevel::Safe);
    }

    #[test]
    fn parse_risk_method_destructive() {
        assert_eq!(parse_risk("method-destructive").unwrap(), RiskLevel::MethodDestructive);
    }

    #[test]
    fn parse_risk_operation_destructive() {
        assert_eq!(parse_risk("operation-destructive").unwrap(), RiskLevel::OperationDestructive);
    }

    #[test]
    fn parse_risk_invalid_returns_err() {
        assert!(parse_risk("invalid").is_err());
    }

    #[test]
    fn parse_known_duplicate_splits_field_and_value() {
        let kd = parse_known_duplicate("email=alice@example.com").unwrap();
        assert_eq!(kd.field, "email");
        assert_eq!(kd.value, "alice@example.com");
    }

    #[test]
    fn parse_known_duplicate_splits_on_first_equals_only() {
        let kd = parse_known_duplicate("foo=bar=baz").unwrap();
        assert_eq!(kd.field, "foo");
        assert_eq!(kd.value, "bar=baz");
    }

    #[test]
    fn parse_known_duplicate_no_divider_returns_err() {
        assert!(parse_known_duplicate("nodivider").is_err());
    }

    #[test]
    fn parse_state_field_splits_correctly() {
        let sf = parse_state_field("status=invalid").unwrap();
        assert_eq!(sf.field, "status");
        assert_eq!(sf.value, "invalid");
    }

    #[test]
    fn build_scan_context_target_matches_and_risk_defaults_to_safe() {
        let args = minimal_args("https://api.example.com/users/{id}", "1001");
        let ctx = build_scan_context(&args, &[]).unwrap();
        assert_eq!(ctx.target, "https://api.example.com/users/{id}");
        assert_eq!(ctx.max_risk, RiskLevel::Safe);
    }
}