zentinel-modsec 0.1.2

//! Comparison operators (@contains, @eq, @gt, etc.).

use super::traits::{Operator, OperatorResult};
use crate::error::{Error, Result};

/// Contains operator (@contains).
pub struct ContainsOperator {
    needle: String,
}

impl ContainsOperator {
    pub fn new(needle: &str) -> Self {
        Self {
            needle: needle.to_string(),
        }
    }
}

impl Operator for ContainsOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if value.contains(&self.needle) {
            OperatorResult::matched(self.needle.clone())
        } else {
            OperatorResult::no_match()
        }
    }

    fn name(&self) -> &'static str {
        "contains"
    }
}

/// BeginsWith operator (@beginsWith).
pub struct BeginsWithOperator {
    prefix: String,
}

impl BeginsWithOperator {
    pub fn new(prefix: &str) -> Self {
        Self {
            prefix: prefix.to_string(),
        }
    }
}

impl Operator for BeginsWithOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if value.starts_with(&self.prefix) {
            OperatorResult::matched(self.prefix.clone())
        } else {
            OperatorResult::no_match()
        }
    }

    fn name(&self) -> &'static str {
        "beginsWith"
    }
}

/// EndsWith operator (@endsWith).
pub struct EndsWithOperator {
    suffix: String,
}

impl EndsWithOperator {
    pub fn new(suffix: &str) -> Self {
        Self {
            suffix: suffix.to_string(),
        }
    }
}

impl Operator for EndsWithOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if value.ends_with(&self.suffix) {
            OperatorResult::matched(self.suffix.clone())
        } else {
            OperatorResult::no_match()
        }
    }

    fn name(&self) -> &'static str {
        "endsWith"
    }
}

/// String equals operator (@streq).
pub struct StreqOperator {
    expected: String,
}

impl StreqOperator {
    pub fn new(expected: &str) -> Self {
        Self {
            expected: expected.to_string(),
        }
    }
}

impl Operator for StreqOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if value == self.expected {
            OperatorResult::matched(value.to_string())
        } else {
            OperatorResult::no_match()
        }
    }

    fn name(&self) -> &'static str {
        "streq"
    }
}

/// Numeric equals operator (@eq).
/// Supports both numeric literals and variable references (e.g., %{tx.var}).
pub struct EqOperator {
    /// The argument (may be a number or variable reference).
    arg: String,
}

impl EqOperator {
    pub fn new(value: &str) -> Self {
        Self {
            arg: value.to_string(),
        }
    }

    fn target_value(&self) -> Option<i64> {
        // If it's a variable reference, we can't resolve it statically
        if self.arg.contains("%{") {
            return None;
        }
        self.arg.parse().ok()
    }
}

impl Operator for EqOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if let Some(target) = self.target_value() {
            if let Ok(n) = value.parse::<i64>() {
                if n == target {
                    return OperatorResult::matched(value.to_string());
                }
            }
        }
        // For variable references, comparison would need runtime resolution
        // For now, we don't match if we can't resolve
        OperatorResult::no_match()
    }

    fn name(&self) -> &'static str {
        "eq"
    }
}

/// Greater than operator (@gt).
pub struct GtOperator {
    arg: String,
}

impl GtOperator {
    pub fn new(value: &str) -> Self {
        Self {
            arg: value.to_string(),
        }
    }

    fn target_value(&self) -> Option<i64> {
        if self.arg.contains("%{") {
            return None;
        }
        self.arg.parse().ok()
    }
}

impl Operator for GtOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if let Some(target) = self.target_value() {
            if let Ok(n) = value.parse::<i64>() {
                if n > target {
                    return OperatorResult::matched(value.to_string());
                }
            }
        }
        OperatorResult::no_match()
    }

    fn name(&self) -> &'static str {
        "gt"
    }
}

/// Less than operator (@lt).
pub struct LtOperator {
    arg: String,
}

impl LtOperator {
    pub fn new(value: &str) -> Self {
        Self {
            arg: value.to_string(),
        }
    }

    fn target_value(&self) -> Option<i64> {
        if self.arg.contains("%{") {
            return None;
        }
        self.arg.parse().ok()
    }
}

impl Operator for LtOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if let Some(target) = self.target_value() {
            if let Ok(n) = value.parse::<i64>() {
                if n < target {
                    return OperatorResult::matched(value.to_string());
                }
            }
        }
        OperatorResult::no_match()
    }

    fn name(&self) -> &'static str {
        "lt"
    }
}

/// Greater than or equal operator (@ge).
pub struct GeOperator {
    arg: String,
}

impl GeOperator {
    pub fn new(value: &str) -> Self {
        Self {
            arg: value.to_string(),
        }
    }

    fn target_value(&self) -> Option<i64> {
        if self.arg.contains("%{") {
            return None;
        }
        self.arg.parse().ok()
    }
}

impl Operator for GeOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if let Some(target) = self.target_value() {
            if let Ok(n) = value.parse::<i64>() {
                if n >= target {
                    return OperatorResult::matched(value.to_string());
                }
            }
        }
        OperatorResult::no_match()
    }

    fn name(&self) -> &'static str {
        "ge"
    }
}

/// Less than or equal operator (@le).
pub struct LeOperator {
    arg: String,
}

impl LeOperator {
    pub fn new(value: &str) -> Self {
        Self {
            arg: value.to_string(),
        }
    }

    fn target_value(&self) -> Option<i64> {
        if self.arg.contains("%{") {
            return None;
        }
        self.arg.parse().ok()
    }
}

impl Operator for LeOperator {
    fn execute(&self, value: &str) -> OperatorResult {
        if let Some(target) = self.target_value() {
            if let Ok(n) = value.parse::<i64>() {
                if n <= target {
                    return OperatorResult::matched(value.to_string());
                }
            }
        }
        OperatorResult::no_match()
    }

    fn name(&self) -> &'static str {
        "le"
    }
}

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

    #[test]
    fn test_contains() {
        let op = ContainsOperator::new("admin");
        assert!(op.execute("/admin/users").matched);
        assert!(!op.execute("/users").matched);
    }

    #[test]
    fn test_begins_with() {
        let op = BeginsWithOperator::new("/admin");
        assert!(op.execute("/admin/users").matched);
        assert!(!op.execute("/users/admin").matched);
    }

    #[test]
    fn test_ends_with() {
        let op = EndsWithOperator::new(".php");
        assert!(op.execute("index.php").matched);
        assert!(!op.execute("index.html").matched);
    }

    #[test]
    fn test_streq() {
        let op = StreqOperator::new("admin");
        assert!(op.execute("admin").matched);
        assert!(!op.execute("Admin").matched);
    }

    #[test]
    fn test_numeric_operators() {
        let eq = EqOperator::new("10");
        assert!(eq.execute("10").matched);
        assert!(!eq.execute("11").matched);

        let gt = GtOperator::new("10");
        assert!(gt.execute("11").matched);
        assert!(!gt.execute("10").matched);

        let lt = LtOperator::new("10");
        assert!(lt.execute("9").matched);
        assert!(!lt.execute("10").matched);
    }
}