foxhunt/common/tests/error_retry_strategy_tests.rs

//! Advanced Retry Strategy and Error Classification Tests
//!
//! This module provides comprehensive tests for:
//! - RetryStrategy::calculate_delay (exponential backoff, linear delays, caps, jitter)
//! - CommonError::severity (all error categories and variants)
//! - CommonError::retry_strategy (retryable vs non-retryable errors)

use common::error::{CommonError, ErrorCategory, ErrorSeverity, RetryStrategy};

// =============================================================================
// RETRY STRATEGY: CALCULATE_DELAY TESTS
// =============================================================================

#[test]
fn test_retry_strategy_calculate_delay_linear_basic() {
    let strategy = RetryStrategy::Linear { base_delay_ms: 100 };

    // Attempt 0: 100ms * 0 = 0ms
    let delay_0 = strategy.calculate_delay(0).expect("should have delay");
    assert_eq!(delay_0.as_millis(), 0);

    // Attempt 1: 100ms * 1 = 100ms
    let delay_1 = strategy.calculate_delay(1).expect("should have delay");
    assert_eq!(delay_1.as_millis(), 100);

    // Attempt 5: 100ms * 5 = 500ms
    let delay_5 = strategy.calculate_delay(5).expect("should have delay");
    assert_eq!(delay_5.as_millis(), 500);
}

#[test]
fn test_retry_strategy_calculate_delay_exponential_basic() {
    let strategy = RetryStrategy::Exponential { base_delay_ms: 100, max_delay_ms: 10000 };

    // Attempt 0: 100 * 2^0 = 100ms (with jitter 90-100ms)
    let delay_0 = strategy.calculate_delay(0).expect("should have delay");
    assert!(delay_0.as_millis() >= 90 && delay_0.as_millis() <= 100);

    // Attempt 1: 100 * 2^1 = 200ms (with jitter 180-200ms)
    let delay_1 = strategy.calculate_delay(1).expect("should have delay");
    assert!(delay_1.as_millis() >= 180 && delay_1.as_millis() <= 200);

    // Attempt 3: 100 * 2^3 = 800ms (with jitter 720-800ms)
    let delay_3 = strategy.calculate_delay(3).expect("should have delay");
    assert!(delay_3.as_millis() >= 720 && delay_3.as_millis() <= 800);
}

#[test]
fn test_retry_strategy_calculate_delay_exponential_capping() {
    let strategy = RetryStrategy::Exponential { base_delay_ms: 100, max_delay_ms: 1000 };

    // Attempt 10: 100 * 2^10 = 102400ms, but capped at min(10) = 100 * 2^10, then max_delay_ms = 1000ms
    let delay_10 = strategy.calculate_delay(10).expect("should have delay");
    assert!(delay_10.as_millis() >= 900 && delay_10.as_millis() <= 1000);

    // Attempt 15: still capped at 1000ms
    let delay_15 = strategy.calculate_delay(15).expect("should have delay");
    assert!(delay_15.as_millis() >= 900 && delay_15.as_millis() <= 1000);

    // Attempt 20: still capped
    let delay_20 = strategy.calculate_delay(20).expect("should have delay");
    assert!(delay_20.as_millis() >= 900 && delay_20.as_millis() <= 1000);
}

#[test]
fn test_retry_strategy_calculate_delay_no_retry() {
    let strategy = RetryStrategy::NoRetry;
    assert!(strategy.calculate_delay(0).is_none());
    assert!(strategy.calculate_delay(1).is_none());
    assert!(strategy.calculate_delay(100).is_none());
}

#[test]
fn test_retry_strategy_calculate_delay_immediate() {
    let strategy = RetryStrategy::Immediate;

    let delay_0 = strategy.calculate_delay(0).expect("should have delay");
    assert_eq!(delay_0.as_millis(), 0);

    let delay_5 = strategy.calculate_delay(5).expect("should have delay");
    assert_eq!(delay_5.as_millis(), 0);
}

#[test]
fn test_retry_strategy_calculate_delay_circuit_breaker() {
    let strategy = RetryStrategy::CircuitBreaker;

    let delay_0 = strategy.calculate_delay(0).expect("should have delay");
    assert_eq!(delay_0.as_secs(), 30);

    let delay_3 = strategy.calculate_delay(3).expect("should have delay");
    assert_eq!(delay_3.as_secs(), 30);
}

// =============================================================================
// ERROR SEVERITY: COMPREHENSIVE CATEGORY TESTS
// =============================================================================

#[test]
fn test_common_error_severity_database() {
    let err = CommonError::Database(
        common::database::DatabaseError::PoolExhausted
    );
    assert_eq!(err.severity(), ErrorSeverity::Critical);
}

#[test]
fn test_common_error_severity_configuration() {
    let err = CommonError::Configuration("Missing API key".to_owned());
    assert_eq!(err.severity(), ErrorSeverity::Critical);
}

#[test]
fn test_common_error_severity_network() {
    let err = CommonError::Network("Connection timeout".to_owned());
    assert_eq!(err.severity(), ErrorSeverity::Error);
}

#[test]
fn test_common_error_severity_validation() {
    let err = CommonError::Validation("Price out of range".to_owned());
    assert_eq!(err.severity(), ErrorSeverity::Warn);
}

#[test]
fn test_common_error_severity_timeout() {
    let err = CommonError::Timeout { actual_ms: 5000, max_ms: 3000 };
    assert_eq!(err.severity(), ErrorSeverity::Error);
}

#[test]
fn test_common_error_severity_service_critical_categories() {
    // Critical severity categories
    let err = CommonError::service(ErrorCategory::Critical, "critical issue");
    assert_eq!(err.severity(), ErrorSeverity::Critical);

    let err = CommonError::service(ErrorCategory::FinancialSafety, "safety breach");
    assert_eq!(err.severity(), ErrorSeverity::Critical);

    let err = CommonError::service(ErrorCategory::Authentication, "auth failed");
    assert_eq!(err.severity(), ErrorSeverity::Critical);
}

#[test]
fn test_common_error_severity_service_error_categories() {
    // Error severity categories
    let err = CommonError::service(ErrorCategory::Trading, "trade failed");
    assert_eq!(err.severity(), ErrorSeverity::Error);

    let err = CommonError::service(ErrorCategory::RiskManagement, "risk violation");
    assert_eq!(err.severity(), ErrorSeverity::Error);

    let err = CommonError::service(ErrorCategory::Database, "service db issue");
    assert_eq!(err.severity(), ErrorSeverity::Error);
}

#[test]
fn test_common_error_severity_service_warn_categories() {
    // Warn severity categories (catch-all)
    let err = CommonError::service(ErrorCategory::MarketData, "stale data");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::System, "system warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Configuration, "config mismatch");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Validation, "validation warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Connection, "unstable connection");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::RateLimit, "throttled");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Parse, "parse warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Subscription, "sub warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Broker, "broker warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::MachineLearning, "ml warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Security, "security warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::BusinessLogic, "logic warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Resource, "resource warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Development, "dev warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Risk, "risk warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::ML, "ml warning");
    assert_eq!(err.severity(), ErrorSeverity::Warn);

    let err = CommonError::service(ErrorCategory::Other, "misc issue");
    assert_eq!(err.severity(), ErrorSeverity::Warn);
}

// =============================================================================
// RETRY STRATEGY: ERROR-SPECIFIC TESTS
// =============================================================================

#[test]
fn test_common_error_retry_strategy_database() {
    let err = CommonError::Database(
        common::database::DatabaseError::PoolExhausted
    );
    assert!(matches!(err.retry_strategy(), RetryStrategy::Exponential { .. }));
}

#[test]
fn test_common_error_retry_strategy_network() {
    let err = CommonError::Network("Connection reset".to_owned());
    assert!(matches!(err.retry_strategy(), RetryStrategy::Linear { .. }));
}

#[test]
fn test_common_error_retry_strategy_timeout() {
    let err = CommonError::Timeout { actual_ms: 5000, max_ms: 3000 };
    assert!(matches!(err.retry_strategy(), RetryStrategy::Linear { .. }));
}

#[test]
fn test_common_error_retry_strategy_non_retryable() {
    // Configuration errors should not be retried
    let err = CommonError::Configuration("Invalid config".to_owned());
    assert!(matches!(err.retry_strategy(), RetryStrategy::NoRetry));

    // Validation errors should not be retried
    let err = CommonError::Validation("Invalid input".to_owned());
    assert!(matches!(err.retry_strategy(), RetryStrategy::NoRetry));
}

#[test]
fn test_common_error_retry_strategy_service_network() {
    let err = CommonError::service(ErrorCategory::Network, "network service error");
    assert!(matches!(err.retry_strategy(), RetryStrategy::Linear { .. }));

    let err = CommonError::service(ErrorCategory::Connection, "connection service error");
    assert!(matches!(err.retry_strategy(), RetryStrategy::Linear { .. }));
}

#[test]
fn test_common_error_retry_strategy_service_rate_limit() {
    let err = CommonError::service(ErrorCategory::RateLimit, "rate limited");
    assert!(matches!(err.retry_strategy(), RetryStrategy::Exponential { .. }));
}

#[test]
fn test_common_error_retry_strategy_service_authentication() {
    let err = CommonError::service(ErrorCategory::Authentication, "auth failed");
    assert!(matches!(err.retry_strategy(), RetryStrategy::NoRetry));
}

#[test]
fn test_common_error_retry_strategy_service_immediate() {
    let err = CommonError::service(ErrorCategory::MarketData, "stale market data");
    assert!(matches!(err.retry_strategy(), RetryStrategy::Immediate));

    let err = CommonError::service(ErrorCategory::Trading, "trade warning");
    assert!(matches!(err.retry_strategy(), RetryStrategy::Immediate));
}

// =============================================================================
// EDGE CASES AND BOUNDARY CONDITIONS
// =============================================================================

#[test]
fn test_retry_strategy_exponential_zero_attempt() {
    let strategy = RetryStrategy::Exponential { base_delay_ms: 50, max_delay_ms: 5000 };
    let delay = strategy.calculate_delay(0).expect("should have delay");
    // 50 * 2^0 = 50ms with jitter (45-50ms)
    assert!(delay.as_millis() >= 45 && delay.as_millis() <= 50);
}

#[test]
fn test_retry_strategy_exponential_large_max_delay() {
    let strategy = RetryStrategy::Exponential { base_delay_ms: 100, max_delay_ms: 100000 };
    // Attempt 5: 100 * 2^5 = 3200ms (no capping)
    let delay_5 = strategy.calculate_delay(5).expect("should have delay");
    assert!(delay_5.as_millis() >= 2880 && delay_5.as_millis() <= 3200);
}

#[test]
fn test_retry_strategy_linear_zero_delay() {
    let strategy = RetryStrategy::Linear { base_delay_ms: 0 };
    let delay = strategy.calculate_delay(0).expect("should have delay");
    assert_eq!(delay.as_millis(), 0);
}