//! Integration tests for the StemeDB API.

#![allow(clippy::expect_used)]

use axum::{
    body::Body,
    http::{Request, StatusCode},
};
use ed25519_dalek::{Signer, SigningKey};
use rand::rngs::OsRng;
use serde_json::json;
use std::sync::Arc;
use tokio::sync::Mutex;
use tower::ServiceExt; // for `oneshot` and `ready`

use stemedb_api::{create_router, AppState};
use stemedb_ingest::Ingestor;
use stemedb_storage::SledStore;
use stemedb_wal::Journal;

/// Test environment that keeps temp directories alive for the test duration.
///
/// The `_temp_dir` field must be kept alive to prevent the directory from
/// being deleted while the Journal and SledStore are still using it.
struct TestEnvironment {
    _temp_dir: tempfile::TempDir,
    state: AppState,
}

/// Test environment with full ingestor for roundtrip tests.
struct TestEnvironmentWithIngestor {
    _temp_dir: tempfile::TempDir,
    state: AppState,
    ingestor: Ingestor<SledStore>,
}

/// Helper to create a test environment with temporary directories.
async fn create_test_env() -> TestEnvironment {
    let temp_dir = tempfile::tempdir().expect("failed to create temp dir");
    let wal_dir = temp_dir.path().join("wal");
    let db_dir = temp_dir.path().join("db");

    std::fs::create_dir_all(&wal_dir).expect("failed to create wal dir");
    std::fs::create_dir_all(&db_dir).expect("failed to create db dir");

    let journal = Journal::open(&wal_dir).expect("failed to open journal");
    let store = SledStore::open(&db_dir).expect("failed to open store");

    let state = AppState::new(journal, store);

    TestEnvironment { _temp_dir: temp_dir, state }
}

/// Helper to create a test environment with a running ingestor for roundtrip tests.
///
/// Note: We need to share the same store between AppState and Ingestor.
/// AppState::new() takes ownership, so we need a different approach:
/// we'll create the ingestor first, then construct AppState manually.
async fn create_test_env_with_ingestor() -> TestEnvironmentWithIngestor {
    use stemedb_storage::GenericQuotaStore;

    let temp_dir = tempfile::tempdir().expect("failed to create temp dir");
    let wal_dir = temp_dir.path().join("wal");
    let db_dir = temp_dir.path().join("db");

    std::fs::create_dir_all(&wal_dir).expect("failed to create wal dir");
    std::fs::create_dir_all(&db_dir).expect("failed to create db dir");

    // Create shared store
    let store = Arc::new(SledStore::open(&db_dir).expect("failed to open store"));

    // Journal for API (writing)
    let journal_for_api =
        Arc::new(Mutex::new(Journal::open(&wal_dir).expect("failed to open journal for API")));

    // Journal for ingestor (reading) - WAL allows multiple readers
    let journal_for_ingestor =
        Arc::new(Mutex::new(Journal::open(&wal_dir).expect("failed to open journal for ingestor")));

    // Create ingestor with shared store
    let ingestor = Ingestor::new(journal_for_ingestor, store.clone())
        .await
        .expect("failed to create ingestor");

    // Create quota store for AppState
    let quota_store = Arc::new(GenericQuotaStore::new(store.clone()));

    // Construct AppState manually to share the store
    let state = AppState { journal: journal_for_api, store, quota_store };

    TestEnvironmentWithIngestor { _temp_dir: temp_dir, state, ingestor }
}

#[tokio::test]
async fn test_health_check() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let request = Request::builder().uri("/v1/health").method("GET").body(Body::empty()).unwrap();

    let response = app.oneshot(request).await.unwrap();

    assert_eq!(response.status(), StatusCode::OK);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();

    assert_eq!(json["status"], "healthy");
    assert!(json["version"].is_string());
    assert_eq!(json["assertions_count"], 0);
}

#[tokio::test]
async fn test_dto_confidence_validation() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Test confidence > 1.0
    let invalid_assertion = json!({
        "subject": "Tesla",
        "predicate": "has_revenue",
        "object": {"type": "Number", "value": 100.0},
        "confidence": 1.5,
        "signatures": [{
            "agent_id": "a".repeat(64),
            "signature": "b".repeat(128),
            "timestamp": 1234567890
        }],
        "source_hash": "c".repeat(64)
    });

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_assertion).unwrap()))
        .unwrap();

    let response = app.clone().oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("Confidence must be between 0.0 and 1.0"));

    // Test confidence < 0.0
    let invalid_assertion = json!({
        "subject": "Tesla",
        "predicate": "has_revenue",
        "object": {"type": "Number", "value": 100.0},
        "confidence": -0.5,
        "signatures": [{
            "agent_id": "a".repeat(64),
            "signature": "b".repeat(128),
            "timestamp": 1234567890
        }],
        "source_hash": "c".repeat(64)
    });

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_assertion).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("Confidence must be between 0.0 and 1.0"));
}

#[tokio::test]
async fn test_dto_weight_validation() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Test weight > 1.0
    let invalid_vote = json!({
        "assertion_hash": "a".repeat(64),
        "agent_id": "b".repeat(64),
        "weight": 1.5,
        "signature": "c".repeat(128)
    });

    let request = Request::builder()
        .uri("/v1/vote")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_vote).unwrap()))
        .unwrap();

    let response = app.clone().oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("Weight must be between 0.0 and 1.0"));

    // Test weight < 0.0
    let invalid_vote = json!({
        "assertion_hash": "a".repeat(64),
        "agent_id": "b".repeat(64),
        "weight": -0.5,
        "signature": "c".repeat(128)
    });

    let request = Request::builder()
        .uri("/v1/vote")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_vote).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("Weight must be between 0.0 and 1.0"));
}

#[tokio::test]
async fn test_hex_decode_wrong_length() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Test assertion with wrong-length source_hash
    let invalid_assertion = json!({
        "subject": "Tesla",
        "predicate": "has_revenue",
        "object": {"type": "Number", "value": 100.0},
        "confidence": 0.9,
        "signatures": [{
            "agent_id": "a".repeat(64),
            "signature": "b".repeat(128),
            "timestamp": 1234567890
        }],
        "source_hash": "abc"  // Too short
    });

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_assertion).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    let error_msg = json["error"].as_str().unwrap();
    assert!(error_msg.contains("Expected 64 hex characters"));
    assert!(error_msg.contains("got 3"));
}

#[tokio::test]
async fn test_hex_decode_valid() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Test assertion with valid hex lengths
    // Note: This will succeed in parsing/validation but may fail in the ingest worker
    // We're primarily testing that hex validation accepts correct-length strings
    let valid_assertion = json!({
        "subject": "Tesla",
        "predicate": "has_revenue",
        "object": {"type": "Number", "value": 100.0},
        "confidence": 0.9,
        "signatures": [{
            "agent_id": "a".repeat(64),
            "signature": "b".repeat(128),
            "timestamp": 1234567890
        }],
        "source_hash": "c".repeat(64)
    });

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&valid_assertion).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();

    // Accept either 201 (success) or 500 (ingest worker not running in test)
    // We're primarily testing that the hex validation doesn't reject valid lengths
    assert!(
        response.status() == StatusCode::CREATED
            || response.status() == StatusCode::INTERNAL_SERVER_ERROR,
        "Expected 201 or 500, got {}",
        response.status()
    );
}

#[tokio::test]
async fn test_dto_to_assertion_invalid_hex() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Test assertion with invalid hex characters
    let invalid_assertion = json!({
        "subject": "Tesla",
        "predicate": "has_revenue",
        "object": {"type": "Number", "value": 100.0},
        "confidence": 0.9,
        "signatures": [{
            "agent_id": "zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz",  // 'z' is not a valid hex character (64 z's)
            "signature": "b".repeat(128),
            "timestamp": 1234567890
        }],
        "source_hash": "c".repeat(64)
    });

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&invalid_assertion).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    let error = json["error"].as_str().unwrap();
    // The error could be "Invalid hex encoding" or similar - just check it's a bad request error
    assert!(!error.is_empty(), "Error message should not be empty");
}

#[tokio::test]
async fn test_query_empty_results() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let request = Request::builder()
        .uri("/v1/query?subject=nonexistent")
        .method("GET")
        .body(Body::empty())
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::OK);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();

    assert_eq!(json["assertions"], json!([]));
    assert_eq!(json["total_count"], 0);
    assert_eq!(json["has_more"], false);
}

// ============================================================================
// Epoch Endpoint Integration Tests
// ============================================================================

#[tokio::test]
async fn test_create_epoch_success() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let epoch = json!({
        "name": "GAAP-2024",
        "start_timestamp": 1704067200
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    let status = response.status();

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();

    assert_eq!(status, StatusCode::CREATED, "Body: {:?}", json);

    assert_eq!(json["status"], "created");
    // BLAKE3 hash = 32 bytes = 64 hex characters
    assert_eq!(json["hash"].as_str().unwrap().len(), 64);
}

#[tokio::test]
async fn test_create_epoch_empty_name_fails() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let epoch = json!({
        "name": "",
        "start_timestamp": 1704067200
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("cannot be empty"));
}

#[tokio::test]
async fn test_create_epoch_whitespace_name_fails() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let epoch = json!({
        "name": "   ",
        "start_timestamp": 1704067200
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("cannot be empty"));
}

#[tokio::test]
async fn test_create_epoch_with_supersedes() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Supersession requires both supersedes hash AND supersession_type
    let epoch = json!({
        "name": "GAAP-2025",
        "supersedes": "a".repeat(64),
        "supersession_type": "Temporal",
        "start_timestamp": 1735689600
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::CREATED);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert_eq!(json["status"], "created");
}

#[tokio::test]
async fn test_create_epoch_supersedes_without_type_fails() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Providing supersedes but NOT supersession_type should fail
    let epoch = json!({
        "name": "GAAP-2025",
        "supersedes": "a".repeat(64),
        // Missing supersession_type!
        "start_timestamp": 1735689600
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert!(json["error"].as_str().unwrap().contains("supersession_type is required"));
}

#[tokio::test]
async fn test_create_epoch_invalid_supersedes_hex() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    let epoch = json!({
        "name": "GAAP-2025",
        "supersedes": "invalid",  // Too short, should be 64 hex chars
        "supersession_type": "Invalidate",
        "start_timestamp": 1735689600
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    // Should complain about hex length
    assert!(json["error"].as_str().unwrap().contains("Expected 64 hex characters"));
}

#[tokio::test]
async fn test_create_epoch_deterministic_id() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Create the same epoch twice - should get the same ID
    let epoch = json!({
        "name": "Deterministic-Test",
        "start_timestamp": 1000
    });

    let request1 = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response1 = app.clone().oneshot(request1).await.unwrap();
    assert_eq!(response1.status(), StatusCode::CREATED);
    let body1 = axum::body::to_bytes(response1.into_body(), usize::MAX).await.unwrap();
    let json1: serde_json::Value = serde_json::from_slice(&body1).unwrap();
    let hash1 = json1["hash"].as_str().unwrap();

    let request2 = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response2 = app.oneshot(request2).await.unwrap();
    assert_eq!(response2.status(), StatusCode::CREATED);
    let body2 = axum::body::to_bytes(response2.into_body(), usize::MAX).await.unwrap();
    let json2: serde_json::Value = serde_json::from_slice(&body2).unwrap();
    let hash2 = json2["hash"].as_str().unwrap();

    // Same input should produce same ID
    assert_eq!(hash1, hash2, "Same epoch input should produce deterministic ID");
}

#[tokio::test]
async fn test_create_epoch_defaults_timestamp() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Omit start_timestamp - should default to current time
    let epoch = json!({
        "name": "Default-Timestamp-Test"
    });

    let request = Request::builder()
        .uri("/v1/epoch")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&epoch).unwrap()))
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::CREATED);

    // If we got 201, the timestamp defaulted successfully
    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let json: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert_eq!(json["status"], "created");
}

// ============================================================================
// Full Pipeline Integration Tests (POST → Ingest → GET roundtrip)
// ============================================================================

/// Create a properly signed assertion for testing.
fn create_signed_assertion_json(subject: &str, predicate: &str, value: f64) -> serde_json::Value {
    let mut csprng = OsRng;
    let signing_key = SigningKey::generate(&mut csprng);
    let verifying_key = signing_key.verifying_key();

    let message = format!("{}:{}", subject, predicate);
    let signature = signing_key.sign(message.as_bytes());

    let timestamp = std::time::SystemTime::now()
        .duration_since(std::time::UNIX_EPOCH)
        .map(|d| d.as_secs())
        .unwrap_or(0);

    json!({
        "subject": subject,
        "predicate": predicate,
        "object": {"type": "Number", "value": value},
        "confidence": 0.95,
        "source_class": "Expert",
        "lifecycle": "Proposed",
        "signatures": [{
            "agent_id": hex::encode(verifying_key.to_bytes()),
            "signature": hex::encode(signature.to_bytes()),
            "timestamp": timestamp
        }],
        "source_hash": "0".repeat(64),
        "timestamp": timestamp
    })
}

/// Test full assertion roundtrip: POST → Ingest → GET
///
/// This test validates the complete pipeline:
/// 1. POST an assertion to /v1/assert (writes to WAL)
/// 2. Run the ingestor to process the WAL entry
/// 3. GET /v1/query to verify the assertion is queryable
#[tokio::test]
async fn test_assertion_roundtrip_with_ingestor() {
    let env = create_test_env_with_ingestor().await;
    let app = create_router(env.state.clone());

    let subject = "RoundtripTest_Entity";
    let predicate = "test_property";
    let value = 42.0;

    // 1. POST the assertion
    let assertion = create_signed_assertion_json(subject, predicate, value);

    let request = Request::builder()
        .uri("/v1/assert")
        .method("POST")
        .header("content-type", "application/json")
        .body(Body::from(serde_json::to_vec(&assertion).unwrap()))
        .unwrap();

    let response = app.clone().oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::CREATED, "POST should succeed with 201");

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let post_result: serde_json::Value = serde_json::from_slice(&body).unwrap();
    assert_eq!(post_result["status"], "created");
    let assertion_hash = post_result["hash"].as_str().expect("hash should be present");
    assert_eq!(assertion_hash.len(), 64, "hash should be 64 hex chars");

    // 2. Run the ingestor to process the pending record (synchronous for testing)
    let bytes_processed = env.ingestor.process_pending().await.expect("ingestor should process");
    assert!(bytes_processed > 0, "Should have processed WAL bytes");

    // 3. GET the assertion via query
    let request = Request::builder()
        .uri(format!("/v1/query?subject={}&predicate={}", subject, predicate))
        .method("GET")
        .body(Body::empty())
        .unwrap();

    let response = app.oneshot(request).await.unwrap();
    assert_eq!(response.status(), StatusCode::OK);

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.unwrap();
    let query_result: serde_json::Value = serde_json::from_slice(&body).unwrap();

    // Verify the assertion is returned correctly
    assert_eq!(query_result["total_count"], 1, "Should find exactly 1 assertion");
    let assertions = query_result["assertions"].as_array().expect("assertions array");
    assert_eq!(assertions.len(), 1);

    let found = &assertions[0];
    assert_eq!(found["subject"], subject);
    assert_eq!(found["predicate"], predicate);
    assert_eq!(found["object"]["type"], "Number");
    assert!((found["object"]["value"].as_f64().unwrap() - value).abs() < 0.001);
    assert_eq!(found["confidence"], 0.95);
}