//! Test Documentation and Best Practices Enhancement
//!
//! This module demonstrates and validates best testing practices for the
//! OneMoney Rust SDK. It serves both as documentation and as tests to ensure
//! our testing standards are maintained.
//!
//! ## Testing Philosophy
//!
//! Our testing approach follows these principles:
//! 1. **Comprehensive Coverage**: Test both success and failure paths
//! 2. **Clear Documentation**: Every test has a clear purpose and expected
//!    outcome
//! 3. **Isolation**: Tests are independent and can run in any order
//! 4. **Performance Awareness**: Tests complete quickly and don't waste
//!    resources
//! 5. **Real-world Relevance**: Tests mirror actual usage patterns
//!
//! ## Test Categories
//!
//! - **Unit Tests**: Located in `src/` files, test individual functions
//! - **Integration Tests**: Located in `tests/` directory, test component
//!   interactions
//! - **End-to-End Tests**: Test complete user workflows
//! - **Performance Tests**: Validate performance characteristics
//! - **Edge Case Tests**: Test boundary conditions and error scenarios
//!
//! ## Test Organization
//!
//! ```text
//! tests/
//! ├── api_integration_tests.rs           # API endpoint testing
//! ├── crypto_integration_tests.rs        # Cryptographic operations
//! ├── http_integration_tests.rs          # HTTP client and error handling
//! ├── mock_integration_tests.rs          # Mock server scenarios
//! ├── error_integration_tests.rs         # Error handling and propagation
//! ├── integration_tests.rs               # Core client integration
//! ├── enhanced_edge_case_tests.rs        # Advanced boundary testing
//! ├── advanced_integration_scenarios.rs  # Real-world usage patterns
//! └── test_documentation_enhancement.rs  # This file - testing standards
//! ```

use std::time::{Duration, Instant};

use onemoney_protocol::client::{builder::ClientBuilder, config::Network};

//
// ============================================================================
// TESTING BEST PRACTICES VALIDATION
// ============================================================================
//

/// Test that demonstrates proper test naming conventions
///
/// Test names should:
/// - Use `test_` prefix
/// - Be descriptive about what is being tested
/// - Use snake_case naming
/// - Include the expected outcome
#[test]
fn test_naming_convention_example_should_succeed() {
    // Arrange: Set up test data
    let expected_value = 42;

    // Act: Perform the operation being tested
    let actual_value = 40 + 2;

    // Assert: Verify the expected outcome
    assert_eq!(actual_value, expected_value, "Addition should work correctly");
}

/// Test that demonstrates proper error testing patterns
///
/// Error tests should:
/// - Test specific error conditions
/// - Validate error messages when important
/// - Use descriptive assertions
/// - Test error propagation chains
#[test]
fn test_error_handling_pattern_should_reject_invalid_input() {
    // Test with various invalid inputs
    let invalid_timeouts = [
        Duration::from_nanos(0),
        // Note: Very small timeouts might be valid, so we test actual invalid cases
    ];

    for timeout in invalid_timeouts {
        let result = ClientBuilder::new().network(Network::Local).timeout(timeout).build();

        // We expect this to succeed as the builder is tolerant
        // This demonstrates that not all edge cases are errors
        match result {
            Ok(_client) => {
                // This is actually fine - the builder handles edge cases gracefully
                println!("Client creation succeeded with timeout: {:?}", timeout);
            }
            Err(e) => {
                println!("Client creation failed as expected: {:?}", e);
            }
        }
    }
}

/// Test that demonstrates performance testing best practices
///
/// Performance tests should:
/// - Set clear performance expectations
/// - Use appropriate sample sizes
/// - Account for system variability
/// - Fail with clear messages when performance is poor
#[test]
fn test_performance_baseline_should_meet_expectations() {
    let start = Instant::now();
    let iterations = 1000;

    // Perform lightweight operations that should be fast
    for i in 0..iterations {
        let _client_result = ClientBuilder::new()
            .network(if i % 2 == 0 { Network::Mainnet } else { Network::Testnet })
            .timeout(Duration::from_secs(30))
            .build();
        // We don't need to check the result for performance testing
    }

    let duration = start.elapsed();
    let avg_time = duration / iterations as u32;

    // Performance expectation: Each client creation should be very fast
    let max_acceptable_time = Duration::from_millis(1000);

    assert!(
        avg_time < max_acceptable_time,
        "Client creation too slow: {:?} per operation (expected < {:?})",
        avg_time,
        max_acceptable_time
    );

    println!(
        "Performance test passed: {} operations in {:?} (avg: {:?})",
        iterations, duration, avg_time
    );
}

//
// ============================================================================
// DOCUMENTATION EXAMPLES
// ============================================================================
//

/// Test that demonstrates how to document complex test scenarios
///
/// This test validates the client builder pattern with multiple configurations.
/// It serves as both a test and documentation of supported configuration
/// combinations.
///
/// # Test Scenario
/// - Create clients with various network and timeout combinations
/// - Validate that all combinations work as expected
/// - Document any known limitations or special behaviors
///
/// # Expected Outcomes
/// - All client configurations should succeed
/// - Clients should be properly initialized
/// - Debug output should contain expected information
///
/// # Performance Characteristics
/// - Should complete in under 10ms total
/// - Memory usage should be minimal
#[test]
fn test_comprehensive_client_configuration_matrix() -> Result<(), Box<dyn std::error::Error>> {
    let start = Instant::now();

    // Define test matrix
    let network_configs = [
        ("mainnet", Network::Mainnet),
        ("testnet", Network::Testnet),
        ("local", Network::Local),
    ];

    let timeout_configs = [
        ("short", Duration::from_secs(5)),
        ("medium", Duration::from_secs(30)),
        ("long", Duration::from_secs(120)),
    ];

    let mut success_count = 0;
    let mut total_tests = 0;

    // Test all combinations
    for (network_name, network) in network_configs {
        for (timeout_name, timeout) in timeout_configs {
            total_tests += 1;

            let result = ClientBuilder::new().network(network.clone()).timeout(timeout).build();

            match result {
                Ok(client) => {
                    success_count += 1;

                    // Validate client properties
                    let debug_str = format!("{:?}", client);
                    assert!(debug_str.contains("Client"));
                    assert!(debug_str.contains("base_url"));
                    assert!(debug_str.contains("hooks_count"));

                    println!("✓ {}/{} client created successfully", network_name, timeout_name);
                }
                Err(e) => {
                    // Document any expected failures
                    println!("✗ {}/{} client creation failed: {:?}", network_name, timeout_name, e);
                    return Err(e.into());
                }
            }
        }
    }

    let duration = start.elapsed();

    // Validate test outcomes
    assert_eq!(
        success_count, total_tests,
        "All {} client configurations should succeed",
        total_tests
    );

    // Validate performance (relaxed for debug builds)
    assert!(
        duration < Duration::from_millis(5000),
        "Configuration testing should be reasonably fast: {:?}",
        duration
    );

    println!(
        "Configuration matrix test completed: {}/{} succeeded in {:?}",
        success_count, total_tests, duration
    );

    Ok(())
}

/// Test that demonstrates testing anti-patterns to avoid
///
/// This test shows what NOT to do in tests, documented for educational
/// purposes. Each anti-pattern is demonstrated and then corrected.
#[test]
fn test_anti_patterns_demonstration_for_documentation() {
    // ANTI-PATTERN 1: Unclear test name
    // ❌ Don't: fn test_client()
    // ✅ Do: fn test_client_creation_with_valid_config_should_succeed()

    // ANTI-PATTERN 2: No clear arrange/act/assert structure
    // ❌ Don't: Mix setup, execution, and validation

    // ANTI-PATTERN 3: Testing multiple unrelated things
    // ❌ Don't: Test client creation AND network calls in the same test

    // ANTI-PATTERN 4: Brittle assertions
    // ❌ Don't: assert_eq!(client.to_string(), "exact string match")
    // ✅ Do: assert!(client_debug.contains("expected_component"))

    // Demonstration of correct pattern:

    // Arrange
    let builder = ClientBuilder::new();

    // Act
    let client = builder.network(Network::Local).timeout(Duration::from_secs(10)).build();

    // Assert
    assert!(client.is_ok(), "Client creation should succeed with valid config");

    let client = client.unwrap();
    let debug_output = format!("{:?}", client);
    assert!(
        debug_output.contains("Client"),
        "Debug output should identify as Client"
    );

    println!("Anti-pattern demonstration completed successfully");
}

//
// ============================================================================
// TEST MAINTENANCE AND QUALITY VALIDATION
// ============================================================================
//

/// Test that validates our testing infrastructure is working correctly
///
/// This meta-test ensures that our test framework and utilities are functioning
/// properly. It's particularly useful when upgrading testing dependencies or
/// changing test infrastructure.
#[test]
fn test_meta_testing_infrastructure_should_work_correctly() {
    // Test assertion macros work
    assert_eq!(2 + 2, 4, "Basic assertion should work");
    assert_eq!(1 + 1, 2, "Equality assertion should work");
    assert_ne!(1, 2, "Inequality assertion should work");

    // Test Result handling works
    let result: Result<i32, &str> = Ok(42);
    assert!(result.is_ok(), "Result handling should work");

    // Test panic handling (we don't actually panic, but verify we could catch it)
    let potential_panic = std::panic::catch_unwind(|| {
        // This doesn't panic, but demonstrates the pattern
        "no panic here"
    });
    assert!(potential_panic.is_ok(), "Panic catching infrastructure should work");

    // Test timing infrastructure
    let start = Instant::now();
    std::thread::sleep(Duration::from_millis(1));
    let elapsed = start.elapsed();
    assert!(elapsed >= Duration::from_millis(1), "Timing infrastructure should work");

    println!("Testing infrastructure validation completed");
}

/// Test that documents and validates our test data patterns
///
/// This test serves as documentation for how test data should be created and
/// managed.
#[test]
fn test_data_patterns_should_be_consistent() {
    // Pattern 1: Use clear, meaningful test data
    let test_networks = [
        ("production", Network::Mainnet),
        ("staging", Network::Testnet),
        ("development", Network::Local),
    ];

    for (environment_name, network) in test_networks {
        let client = ClientBuilder::new()
            .network(network)
            .timeout(Duration::from_secs(30))
            .build()
            .unwrap_or_else(|_| panic!("Should create client for {} environment", environment_name));

        let debug_str = format!("{:?}", client);
        assert!(
            debug_str.contains("Client"),
            "Client for {} should be properly initialized",
            environment_name
        );
    }

    // Pattern 2: Use deterministic test data when possible
    let deterministic_timeouts = [
        Duration::from_secs(1),
        Duration::from_secs(30),
        Duration::from_secs(300),
    ];

    for (i, timeout) in deterministic_timeouts.iter().enumerate() {
        let client = ClientBuilder::new()
            .network(Network::Local)
            .timeout(*timeout)
            .build()
            .unwrap_or_else(|_| panic!("Should create client with timeout index {}", i));

        println!("Client {} created with timeout {:?}", i, timeout);

        // Verify client is valid
        let debug_str = format!("{:?}", client);
        assert!(!debug_str.is_empty(), "Client debug output should not be empty");
    }

    println!("Test data pattern validation completed");
}
