//! Test library for Intel 400x common functionality
//!
//! This module provides a centralized entry point for all tests
//! and exports common testing utilities.

#![cfg(test)]

// Re-export the rusty_emu crate for use in tests
pub use rusty_emu;

// Module declarations for test files
mod gui_integration_tests;
mod gui_tests;
mod integration_tests;
mod intel_4001_state_machine_test;
mod intel_400x_tests;

// Common test utilities and helpers
pub mod test_utils {
    use std::sync::Arc;
    use std::time::{Duration, Instant};

    /// Create a deterministic time source for testing
    pub fn create_test_time() -> Instant {
        Instant::now()
    }

    /// Create a test duration for timing-sensitive tests
    pub fn create_test_duration(nanos: u64) -> Duration {
        Duration::from_nanos(nanos)
    }

    /// Helper to advance time in tests
    pub fn advance_test_time(duration: Duration) {
        std::thread::sleep(duration);
    }

    /// Create a VirtualClock in MaxSpeed mode for fast deterministic tests.
    ///
    /// The clock starts in stopped state. Call `clock.start()` after spawning
    /// the governor thread.
    ///
    /// # Parameters
    /// - `tick_size_ns`: Virtual time advance per tick (default: 333ns for 750 kHz)
    pub fn create_maxspeed_clock(tick_size_ns: u64) -> Arc<rusty_emu::virtual_clock::VirtualClock> {
        let clock = Arc::new(rusty_emu::virtual_clock::VirtualClock::new(
            Duration::from_nanos(tick_size_ns),
        ));
        clock.set_mode(rusty_emu::virtual_clock::SimulationMode::MaxSpeed);
        clock
    }

    /// Create a VirtualClock in SingleStep mode for precise state verification.
    ///
    /// Each call to `clock.trigger_step()` advances virtual time by one tick.
    pub fn create_singlestep_clock(tick_size_ns: u64) -> Arc<rusty_emu::virtual_clock::VirtualClock> {
        let clock = Arc::new(rusty_emu::virtual_clock::VirtualClock::new(
            Duration::from_nanos(tick_size_ns),
        ));
        clock.set_mode(rusty_emu::virtual_clock::SimulationMode::SingleStep);
        clock
    }

    /// Spawn a RealTimeGovernor thread for the given clock.
    ///
    /// Returns a JoinHandle that can be used to wait for the governor to exit.
    /// The governor will exit when `clock.stop()` is called.
    pub fn spawn_governor(
        clock: Arc<rusty_emu::virtual_clock::VirtualClock>,
    ) -> std::thread::JoinHandle<()> {
        std::thread::spawn(move || {
            let governor = rusty_emu::real_time_governor::RealTimeGovernor::with_defaults(clock);
            governor.run();
        })
    }

    /// Stop the virtual clock and wait for the governor thread to finish.
    ///
    /// This ensures clean shutdown of the governor thread before the test ends.
    pub fn stop_governor(
        clock: &Arc<rusty_emu::virtual_clock::VirtualClock>,
        handle: std::thread::JoinHandle<()>,
    ) {
        clock.stop();
        // Give the governor thread a moment to exit cleanly
        let _ = handle.join();
    }

    /// Verify that a component implements all required traits
    pub fn verify_intel400x_traits<C>(component: &C)
    where
        C: rusty_emu::components::common::intel_400x::Intel400xClockHandling,
        C: rusty_emu::components::common::intel_400x::Intel400xDataBus,
        C: rusty_emu::components::common::intel_400x::Intel400xAddressHandling,
        C: rusty_emu::components::common::intel_400x::Intel400xControlPins,
        C: rusty_emu::components::common::intel_400x::Intel400xResetHandling,
        C: rusty_emu::components::common::intel_400x::Intel400xTimingState,
    {
        // Test Intel400xClockHandling
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xClockHandling = component;

        // Test Intel400xDataBus
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xDataBus = component;

        // Test Intel400xAddressHandling
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xAddressHandling = component;

        // Test Intel400xControlPins
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xControlPins = component;

        // Test Intel400xResetHandling
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xResetHandling = component;

        // Test Intel400xTimingState
        let _: &dyn rusty_emu::components::common::intel_400x::Intel400xTimingState = component;
    }

    /// Test that timing constants are reasonable
    #[allow(dead_code)]
    pub fn verify_timing_constants() {
        use rusty_emu::components::common::intel_400x::TimingConstants;

        // Fast access should be faster than default
        assert!(TimingConstants::FAST_ACCESS_TIME < TimingConstants::DEFAULT_ACCESS_TIME);
    }

    /// Test that state machine properties hold
    #[allow(dead_code)]
    pub fn verify_state_machine_properties() {
        use rusty_emu::components::common::intel_400x::TimingState;

        let states = vec![
            TimingState::Idle,
            TimingState::AddressPhase,
            TimingState::WaitLatency,
            TimingState::DriveData,
        ];

        for state in states {
            // Each state should have consistent query results
            match state {
                TimingState::Idle => {
                    assert!(state.is_idle());
                    assert!(!state.is_address_phase());
                    assert!(!state.is_waiting_latency());
                    assert!(!state.is_driving_data());
                }
                TimingState::AddressPhase => {
                    assert!(!state.is_idle());
                    assert!(state.is_address_phase());
                    assert!(!state.is_waiting_latency());
                    assert!(!state.is_driving_data());
                }
                TimingState::WaitLatency => {
                    assert!(!state.is_idle());
                    assert!(!state.is_address_phase());
                    assert!(state.is_waiting_latency());
                    assert!(!state.is_driving_data());
                }
                TimingState::DriveData => {
                    assert!(!state.is_idle());
                    assert!(!state.is_address_phase());
                    assert!(!state.is_waiting_latency());
                    assert!(state.is_driving_data());
                }
            }
        }
    }
}

// Test configuration and setup
pub mod test_config {
    /// Test configuration for running the test suite
    pub struct TestConfig {
        pub enable_detailed_output: bool,
        pub enable_timing_tests: bool,
        pub enable_property_tests: bool,
    }

    impl Default for TestConfig {
        fn default() -> Self {
            Self {
                enable_detailed_output: false,
                enable_timing_tests: true,
                enable_property_tests: true,
            }
        }
    }

    impl TestConfig {
        pub fn with_detailed_output(mut self) -> Self {
            self.enable_detailed_output = true;
            self
        }

        pub fn without_timing_tests(mut self) -> Self {
            self.enable_timing_tests = false;
            self
        }

        pub fn without_property_tests(mut self) -> Self {
            self.enable_property_tests = false;
            self
        }
    }
}