//! Comprehensive HTTP integration tests for the StemeDB API.
//!
//! These tests verify the full HTTP layer without background workers,
//! focusing on request validation, error handling, and response structure.
//!
//! Coverage:
//! - POST /v1/assert - Assertion creation
//! - POST /v1/vote - Vote submission
//! - GET /v1/query - Query with lens parameter
//! - Error responses (400, 500)
//! - Rate limiting via QuotaStore (when enabled)

#![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 tower::ServiceExt;

use stemedb_api::{create_router, create_router_with_meter, AppState};
use stemedb_storage::{GenericQuotaStore, QuotaStore, SledStore};
use stemedb_wal::Journal;

// ============================================================================
// Test Environment Setup
// ============================================================================

/// Test environment that keeps temp directories alive for the test duration.
struct TestEnvironment {
    _temp_dir: tempfile::TempDir,
    state: AppState,
}

/// 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 sign a message using Ed25519.
fn sign_message(message: &str) -> ([u8; 32], [u8; 64]) {
    let mut csprng = OsRng;
    let signing_key = SigningKey::generate(&mut csprng);
    let verifying_key = signing_key.verifying_key();

    let signature = signing_key.sign(message.as_bytes());

    (verifying_key.to_bytes(), signature.to_bytes())
}

// ============================================================================
// POST /v1/assert - Create Assertion Tests
// ============================================================================

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

    let subject = "Test_Entity";
    let predicate = "test_property";
    let message = format!("{}:{}", subject, predicate);
    let (agent_id, signature) = sign_message(&message);

    let assertion = json!({
        "subject": subject,
        "predicate": predicate,
        "object": {"type": "Number", "value": 42.0},
        "confidence": 0.95,
        "signatures": [{
            "agent_id": hex::encode(agent_id),
            "signature": hex::encode(signature),
            "timestamp": 1234567890
        }],
        "source_hash": hex::encode([0u8; 32])
    });

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

    let response = app.oneshot(request).await.expect("Request failed");

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

    let body =
        axum::body::to_bytes(response.into_body(), usize::MAX).await.expect("Failed to read body");
    let json: serde_json::Value = serde_json::from_slice(&body).expect("Failed to parse JSON");

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

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

    let (agent_id, signature) = sign_message("Test:test");

    let assertion = json!({
        "subject": "Test",
        "predicate": "test",
        "object": {"type": "Text", "value": "test_value"},
        "confidence": 0.8,
        "signatures": [{
            "agent_id": hex::encode(agent_id),
            "signature": hex::encode(signature),
            "timestamp": 1000000000
        }],
        "source_hash": hex::encode([1u8; 32])
    });

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

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

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.expect("Body");
    let json: serde_json::Value = serde_json::from_slice(&body).expect("JSON parse");

    // Verify hash is present and correctly formatted
    let hash = json["hash"].as_str().expect("hash should be present");
    assert_eq!(hash.len(), 64);
    assert!(hash.chars().all(|c| c.is_ascii_hexdigit()));
}

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

    let assertion = json!({
        "subject": "Test",
        "predicate": "test",
        "object": {"type": "Number", "value": 1.0},
        "confidence": 0.9,
        "signatures": [], // Empty signatures
        "source_hash": hex::encode([0u8; 32])
    });

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

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

    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.expect("Body");
    let json: serde_json::Value = serde_json::from_slice(&body).expect("JSON");
    assert!(json["error"]
        .as_str()
        .expect("error message")
        .contains("At least one signature is required"));
}

// ============================================================================
// POST /v1/vote - Submit Vote Tests
// ============================================================================

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

    let (agent_id, signature) = sign_message("vote_message");

    let vote = json!({
        "assertion_hash": hex::encode([0u8; 32]),
        "agent_id": hex::encode(agent_id),
        "weight": 0.75,
        "signature": hex::encode(signature)
    });

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

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

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

    assert_eq!(json["status"], "created");
    assert!(json["hash"].is_string());
    assert_eq!(json["hash"].as_str().expect("hash").len(), 64);
}

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

    let (agent_id, signature) = sign_message("test");

    let vote = json!({
        "assertion_hash": hex::encode([1u8; 32]),
        "agent_id": hex::encode(agent_id),
        "weight": 1.0,
        "signature": hex::encode(signature)
    });

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

    let response = app.oneshot(request).await.expect("Request");
    let body = axum::body::to_bytes(response.into_body(), usize::MAX).await.expect("Body");
    let json: serde_json::Value = serde_json::from_slice(&body).expect("JSON");

    // Verify response structure matches CreateResponse
    assert!(json.get("hash").is_some());
    assert!(json.get("status").is_some());
    assert_eq!(json.as_object().expect("object").len(), 2);
}

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

    let (agent_id, signature) = sign_message("test");

    // Test weight > 1.0
    let vote = json!({
        "assertion_hash": hex::encode([0u8; 32]),
        "agent_id": hex::encode(agent_id),
        "weight": 1.5,
        "signature": hex::encode(signature)
    });

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

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

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

// ============================================================================
// GET /v1/query - Query Assertions Tests
// ============================================================================

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

    let request = Request::builder()
        .uri("/v1/query?subject=Test_Entity&predicate=test_property")
        .method("GET")
        .body(Body::empty())
        .expect("Request");

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

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

    // Verify response structure (empty since DB is empty)
    assert!(json.get("assertions").is_some());
    assert!(json.get("total_count").is_some());
    assert!(json.get("has_more").is_some());
    assert_eq!(json["assertions"], json!([]));
    assert_eq!(json["total_count"], 0);
}

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

    let request = Request::builder()
        .uri("/v1/query?subject=Test&predicate=prop&lens=Recency")
        .method("GET")
        .body(Body::empty())
        .expect("Request");

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

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

    // When a lens is applied (even with empty results), conflict_score and
    // resolution_confidence should be None (empty result set)
    assert_eq!(json["assertions"], json!([]));
    assert_eq!(json["total_count"], 0);
    assert!(json.get("conflict_score").is_none() || json["conflict_score"].is_null());
    assert!(json.get("resolution_confidence").is_none() || json["resolution_confidence"].is_null());
}

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

    let request = Request::builder()
        .uri("/v1/query?subject=Test&lifecycle=Approved")
        .method("GET")
        .body(Body::empty())
        .expect("Request");

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

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

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

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

    let request = Request::builder()
        .uri("/v1/query?subject=Test&limit=10")
        .method("GET")
        .body(Body::empty())
        .expect("Request");

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

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

    // Verify query executes successfully (limit parameter is accepted)
    assert!(json.get("assertions").is_some());
}

// ============================================================================
// Error Response Tests
// ============================================================================

#[tokio::test]
async fn test_400_bad_request_invalid_input() {
    let env = create_test_env().await;
    let app = create_router(env.state);

    // Invalid JSON payload
    let invalid_json = b"{invalid json}";

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

    let response = app.oneshot(request).await.expect("Request");
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);
}

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

    // Send assertion with invalid confidence
    let (agent_id, signature) = sign_message("test");

    let assertion = json!({
        "subject": "Test",
        "predicate": "test",
        "object": {"type": "Number", "value": 1.0},
        "confidence": 2.0, // Invalid: > 1.0
        "signatures": [{
            "agent_id": hex::encode(agent_id),
            "signature": hex::encode(signature),
            "timestamp": 1000
        }],
        "source_hash": hex::encode([0u8; 32])
    });

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

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

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

    // Verify error response structure matches ErrorResponse DTO
    assert!(json.get("error").is_some());
    assert!(json.get("code").is_some());
    assert!(json["error"].as_str().expect("error message").contains("Confidence"));
}

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

    let (agent_id, signature) = sign_message("test");

    let assertion = json!({
        "subject": "Test",
        "predicate": "test",
        "object": {"type": "Number", "value": 1.0},
        "confidence": 0.9,
        "signatures": [{
            "agent_id": hex::encode(agent_id),
            "signature": hex::encode(signature),
            "timestamp": 1000
        }],
        "source_hash": "abc" // Too short - should be 64 hex chars
    });

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

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

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

// ============================================================================
// Rate Limiting Tests (QuotaStore Middleware)
// ============================================================================

#[tokio::test]
async fn test_quota_consumption_with_meter() {
    let temp_dir = tempfile::tempdir().expect("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("wal dir");
    std::fs::create_dir_all(&db_dir).expect("db dir");

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

    // Create AppState manually to share quota_store
    let quota_store = Arc::new(GenericQuotaStore::new(store.clone()));
    let state = AppState {
        journal: Arc::new(tokio::sync::Mutex::new(journal)),
        store: store.clone(),
        quota_store: quota_store.clone(),
    };

    let app = create_router_with_meter(state);

    let (agent_id, signature) = sign_message("test");
    let agent_id_hex = hex::encode(agent_id);

    // Set a low quota limit for testing
    quota_store.set_quota_limit(&agent_id, 50).await.expect("set quota");

    let assertion = json!({
        "subject": "QuotaTest",
        "predicate": "test",
        "object": {"type": "Number", "value": 1.0},
        "confidence": 0.9,
        "signatures": [{
            "agent_id": agent_id_hex,
            "signature": hex::encode(signature),
            "timestamp": 1000
        }],
        "source_hash": hex::encode([0u8; 32])
    });

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

    let response = app.oneshot(request).await.expect("Request");

    // Should succeed and include quota headers
    assert_eq!(response.status(), StatusCode::CREATED);

    let headers = response.headers();
    assert!(headers.get("x-quota-remaining").is_some());
    assert!(headers.get("x-quota-limit").is_some());
    assert!(headers.get("x-quota-reset").is_some());
}

#[tokio::test]
async fn test_quota_exceeded_response() {
    let temp_dir = tempfile::tempdir().expect("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("wal dir");
    std::fs::create_dir_all(&db_dir).expect("db dir");

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

    let quota_store = Arc::new(GenericQuotaStore::new(store.clone()));
    let state = AppState {
        journal: Arc::new(tokio::sync::Mutex::new(journal)),
        store: store.clone(),
        quota_store: quota_store.clone(),
    };

    let app = create_router_with_meter(state);

    let (agent_id, _) = sign_message("test");
    let agent_id_hex = hex::encode(agent_id);

    // Set quota to 0 to immediately trigger quota exceeded
    quota_store.set_quota_limit(&agent_id, 0).await.expect("set quota");

    let request = Request::builder()
        .uri("/v1/query?subject=Test")
        .method("GET")
        .header("x-agent-id", &agent_id_hex)
        .body(Body::empty())
        .expect("Request");

    let response = app.oneshot(request).await.expect("Request");

    // Should return 429 Too Many Requests
    assert_eq!(response.status(), StatusCode::TOO_MANY_REQUESTS);

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

    assert!(json.get("error").is_some());
    assert_eq!(json["code"], "QUOTA_EXCEEDED");
    assert!(json.get("remaining").is_some());
    assert!(json.get("limit").is_some());
    assert!(json.get("reset_at").is_some());
}

// ============================================================================
// Additional Edge Cases
// ============================================================================

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

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

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

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

    assert_eq!(json["status"], "healthy");
    assert!(json.get("version").is_some());
}

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

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

    let response = app.oneshot(request).await.expect("Request");
    assert_eq!(response.status(), StatusCode::NOT_FOUND);
}

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

    // Test that all lens values are accepted
    let lenses = vec!["Recency", "Consensus", "Confidence", "Authority", "VoteAwareConsensus"];

    for lens in lenses {
        let request = Request::builder()
            .uri(format!("/v1/query?subject=Test&predicate=prop&lens={}", lens))
            .method("GET")
            .body(Body::empty())
            .expect("Request");

        let response = app.clone().oneshot(request).await.expect("Request");
        assert_eq!(response.status(), StatusCode::OK, "Lens {} should be accepted", lens);
    }
}