//! PPO Adapter Training Paths Integration Test
//!
//! Validates that PPO hyperopt adapter properly uses TrainingPaths
//! instead of hardcoded checkpoint directories.
//!
//! This test ensures:
//! - No hardcoded paths in PPOTrainer
//! - TrainingPaths can be configured via with_training_paths()
//! - Default paths use /tmp/ml_training as temporary default
//! - Paths are correctly propagated to training logic

use std::path::PathBuf;
use tempfile::TempDir;

use ml::hyperopt::adapters::ppo::PPOTrainer;
use ml::hyperopt::paths::{generate_run_id, TrainingPaths};

#[test]
fn test_ppo_trainer_default_paths() {
    // Create trainer with default paths
    let trainer = PPOTrainer::new(100).expect("Failed to create PPO trainer");

    // Default paths should use /tmp/ml_training
    // This is intentional - provides a safe temporary default
    // Production code MUST call with_training_paths()
    let expected_base = PathBuf::from("/tmp/ml_training");

    // Access training_paths via debug formatting (struct is Debug)
    let debug_str = format!("{:?}", trainer);
    assert!(
        debug_str.contains("/tmp/ml_training"),
        "Default paths should use /tmp/ml_training, got: {}",
        debug_str
    );
}

#[test]
fn test_ppo_trainer_custom_paths() {
    // Create temporary directory for test
    let temp_dir = TempDir::new().expect("Failed to create temp dir");
    let base_dir = temp_dir.path();

    // Generate run ID
    let run_id = generate_run_id("test");

    // Create training paths
    let training_paths = TrainingPaths::new(base_dir, "ppo", &run_id);

    // Create directories
    training_paths
        .create_all()
        .expect("Failed to create training directories");

    // Create trainer with custom paths
    let trainer = PPOTrainer::new(100)
        .expect("Failed to create PPO trainer")
        .with_training_paths(training_paths.clone());

    // Validate paths are set correctly
    let expected_run_dir = base_dir
        .join("training_runs")
        .join("ppo")
        .join(format!("run_{}", run_id));

    let expected_checkpoints = expected_run_dir.join("checkpoints");

    // Verify directories exist
    assert!(
        expected_run_dir.exists(),
        "Run directory should exist: {:?}",
        expected_run_dir
    );
    assert!(
        expected_checkpoints.exists(),
        "Checkpoints directory should exist: {:?}",
        expected_checkpoints
    );

    // Verify paths are used (via debug formatting)
    let debug_str = format!("{:?}", trainer);
    assert!(
        debug_str.contains("model_name: \"ppo\""),
        "Trainer should use model_name 'ppo', got: {}",
        debug_str
    );
    assert!(
        debug_str.contains(&run_id),
        "Trainer should use provided run_id, got: {}",
        debug_str
    );
}

#[test]
fn test_ppo_trainer_path_structure() {
    // Create temporary directory
    let temp_dir = TempDir::new().expect("Failed to create temp dir");
    let base_dir = temp_dir.path();

    // Create training paths with known run_id
    let run_id = "20251029_120000_test";
    let training_paths = TrainingPaths::new(base_dir, "ppo", run_id);

    // Create all directories
    training_paths
        .create_all()
        .expect("Failed to create directories");

    // Create trainer with paths
    let _trainer = PPOTrainer::new(100)
        .expect("Failed to create trainer")
        .with_training_paths(training_paths.clone());

    // Validate full directory structure
    let run_dir = training_paths.run_dir();
    let checkpoints = training_paths.checkpoints_dir();
    let logs = training_paths.logs_dir();
    let hyperopt = training_paths.hyperopt_dir();
    let metrics = training_paths.metrics_dir();

    assert!(run_dir.exists(), "Run directory should exist");
    assert!(checkpoints.exists(), "Checkpoints directory should exist");
    assert!(logs.exists(), "Logs directory should exist");
    assert!(hyperopt.exists(), "Hyperopt directory should exist");
    assert!(metrics.exists(), "Metrics directory should exist");

    // Validate path relationships
    assert_eq!(
        checkpoints,
        run_dir.join("checkpoints"),
        "Checkpoints should be under run_dir"
    );
    assert_eq!(logs, run_dir.join("logs"), "Logs should be under run_dir");
    assert_eq!(
        hyperopt,
        run_dir.join("hyperopt"),
        "Hyperopt should be under run_dir"
    );
    assert_eq!(
        metrics,
        run_dir.join("metrics"),
        "Metrics should be under run_dir"
    );
}

#[test]
fn test_run_id_generation() {
    // Generate run ID
    let run_id = generate_run_id("hyperopt");

    // Validate format
    assert!(
        run_id.contains("hyperopt"),
        "Run ID should contain run type"
    );
    assert!(
        run_id.len() > 15,
        "Run ID should have timestamp (YYYYMMDD_HHMMSS)"
    );

    // Validate uniqueness (generate multiple)
    let run_id_2 = generate_run_id("hyperopt");
    // Should be the same or different depending on timing
    // Just validate format consistency
    assert!(run_id_2.contains("hyperopt"));
    assert!(run_id_2.len() > 15);
}

#[test]
fn test_ppo_trainer_builder_pattern() {
    // Test builder pattern with training paths
    let temp_dir = TempDir::new().expect("Failed to create temp dir");
    let training_paths = TrainingPaths::new(temp_dir.path(), "ppo", "test_builder");

    training_paths
        .create_all()
        .expect("Failed to create directories");

    // Build trainer with method chaining
    let trainer = PPOTrainer::new(100)
        .expect("Failed to create trainer")
        .with_training_paths(training_paths.clone());

    // Verify trainer was created successfully
    let debug_str = format!("{:?}", trainer);
    assert!(debug_str.contains("test_builder"));
    assert!(debug_str.contains("ppo"));
}