use axum::{
    Router,
    body::Body,
    http::{Method, Request, StatusCode, header},
    response::Response,
};
use http_body_util::BodyExt;
use serde_json::{Value, json};
use sqlx::{
    SqlitePool,
    sqlite::{SqliteConnectOptions, SqlitePoolOptions},
};
use task_pilot_backend::database;
use tempfile::TempDir;
use tower::ServiceExt;

async fn test_app() -> (Router, TempDir) {
    let temp_dir = TempDir::new().expect("temporary directory should be created");
    let pool = database::connect("sqlite::memory:")
        .await
        .expect("test database should initialize");
    let app = task_pilot_backend::app(pool, temp_dir.path().join("logs"))
        .await
        .expect("test app should start");
    (app, temp_dir)
}

async fn connect_file(path: &std::path::Path) -> SqlitePool {
    let options = SqliteConnectOptions::new()
        .filename(path)
        .create_if_missing(true)
        .foreign_keys(true);
    let pool = SqlitePoolOptions::new()
        .max_connections(1)
        .connect_with(options)
        .await
        .expect("file database should open");
    database::migrate(&pool)
        .await
        .expect("migrations should run");
    pool
}

async fn send_json(app: &Router, method: Method, uri: &str, body: Option<Value>) -> Response {
    let token = if matches!(method, Method::GET | Method::HEAD | Method::OPTIONS) {
        None
    } else {
        Some(fetch_api_token(app).await)
    };
    let body = body
        .map(|value| Body::from(serde_json::to_vec(&value).expect("JSON should serialize")))
        .unwrap_or_else(Body::empty);
    let mut builder = Request::builder()
        .method(method)
        .uri(uri)
        .header(header::CONTENT_TYPE, "application/json");
    if let Some(token) = token {
        builder = builder.header("x-taskpilot-token", token);
    }
    let request = builder.body(body).expect("request should build");

    app.clone()
        .oneshot(request)
        .await
        .expect("router should respond")
}

async fn fetch_api_token(app: &Router) -> String {
    let request = Request::builder()
        .method(Method::GET)
        .uri("/api/v1/session")
        .body(Body::empty())
        .expect("session request should build");
    let response = app
        .clone()
        .oneshot(request)
        .await
        .expect("session endpoint should respond");
    assert_eq!(response.status(), StatusCode::OK);
    response_json(response).await["token"]
        .as_str()
        .expect("session token should be a string")
        .to_owned()
}

async fn response_json(response: Response) -> Value {
    let body = response
        .into_body()
        .collect()
        .await
        .expect("response body should be readable")
        .to_bytes();
    serde_json::from_slice(&body).expect("response should be JSON")
}

fn script_task(id: &str, name: &str) -> Value {
    json!({
        "id": id,
        "name": name,
        "cron": "0 0 2 * * *",
        "enabled": true,
        "timeout_secs": 300,
        "action": {
            "type": "script",
            "working_dir": "D:\\Projects\\sync",
            "interpreter": "python.exe",
            "script": "main.py",
            "args": ["--mode", "full"],
            "env": {
                "PYTHONUNBUFFERED": "1"
            }
        }
    })
}

#[tokio::test]
async fn empty_interpreter_defaults_to_python() {
    let (app, _temp_dir) = test_app().await;
    let mut payload = script_task("default_interpreter", "Default interpreter");
    payload["action"]["interpreter"] = json!("");

    let response = send_json(&app, Method::POST, "/api/v1/tasks", Some(payload)).await;

    assert_eq!(response.status(), StatusCode::CREATED);
    let created = response_json(response).await;
    assert_eq!(created["action"]["interpreter"], "python.exe");
    assert_eq!(created["action"]["language"], "python");
}

#[tokio::test]
async fn task_crud_flow_works_end_to_end() {
    let (app, _temp_dir) = test_app().await;

    let create_response = send_json(
        &app,
        Method::POST,
        "/api/v1/tasks",
        Some(script_task("sync_data", "Data sync")),
    )
    .await;
    assert_eq!(create_response.status(), StatusCode::CREATED);
    let created = response_json(create_response).await;
    assert_eq!(created["id"], "sync_data");
    assert_eq!(created["timezone"], "Asia/Shanghai");
    assert_eq!(created["action"]["type"], "script");

    let get_response = send_json(&app, Method::GET, "/api/v1/tasks/sync_data", None).await;
    assert_eq!(get_response.status(), StatusCode::OK);
    assert_eq!(response_json(get_response).await["name"], "Data sync");

    let list_response = send_json(
        &app,
        Method::GET,
        "/api/v1/tasks?q=sync&enabled=true&action_type=script&page=1&page_size=10",
        None,
    )
    .await;
    assert_eq!(list_response.status(), StatusCode::OK);
    let listed = response_json(list_response).await;
    assert_eq!(listed["total"], 1);
    assert_eq!(listed["items"][0]["id"], "sync_data");

    let update_response = send_json(
        &app,
        Method::PUT,
        "/api/v1/tasks/sync_data",
        Some(json!({
            "name": "Updated data sync",
            "cron": "*/30 * * * * *",
            "enabled": false,
            "timeout_secs": 120,
            "action": {
                "type": "http",
                "url": "https://example.com/health",
                "method": "GET",
                "headers": {},
                "expected_status": [200]
            }
        })),
    )
    .await;
    assert_eq!(update_response.status(), StatusCode::OK);
    let updated = response_json(update_response).await;
    assert_eq!(updated["name"], "Updated data sync");
    assert_eq!(updated["enabled"], false);
    assert_eq!(updated["action"]["type"], "http");

    let delete_response = send_json(&app, Method::DELETE, "/api/v1/tasks/sync_data", None).await;
    assert_eq!(delete_response.status(), StatusCode::NO_CONTENT);

    let missing_response = send_json(&app, Method::GET, "/api/v1/tasks/sync_data", None).await;
    assert_eq!(missing_response.status(), StatusCode::NOT_FOUND);
    let missing = response_json(missing_response).await;
    assert_eq!(missing["code"], "TASK_NOT_FOUND");
}

#[tokio::test]
async fn duplicate_task_id_returns_conflict() {
    let (app, _temp_dir) = test_app().await;
    let first = send_json(
        &app,
        Method::POST,
        "/api/v1/tasks",
        Some(script_task("duplicate", "First")),
    )
    .await;
    assert_eq!(first.status(), StatusCode::CREATED);

    let second = send_json(
        &app,
        Method::POST,
        "/api/v1/tasks",
        Some(script_task("duplicate", "Second")),
    )
    .await;
    assert_eq!(second.status(), StatusCode::CONFLICT);
    let body = response_json(second).await;
    assert_eq!(body["code"], "TASK_ID_CONFLICT");
    assert_eq!(body["field"], "id");
}

#[tokio::test]
async fn invalid_cron_returns_structured_validation_error() {
    let (app, _temp_dir) = test_app().await;
    let mut request = script_task("invalid_cron", "Invalid cron");
    request["cron"] = Value::String("*/0 * * * * *".to_owned());

    let response = send_json(&app, Method::POST, "/api/v1/tasks", Some(request)).await;
    assert_eq!(response.status(), StatusCode::BAD_REQUEST);
    let body = response_json(response).await;
    assert_eq!(body["code"], "VALIDATION_ERROR");
    assert_eq!(body["field"], "cron");
}

#[tokio::test]
async fn malformed_json_and_query_return_structured_errors() {
    let (app, _temp_dir) = test_app().await;
    let token = fetch_api_token(&app).await;
    let malformed_request = Request::builder()
        .method(Method::POST)
        .uri("/api/v1/tasks")
        .header(header::CONTENT_TYPE, "application/json")
        .header("x-taskpilot-token", token)
        .body(Body::from("{not-json"))
        .expect("request should build");
    let malformed_response = app
        .clone()
        .oneshot(malformed_request)
        .await
        .expect("router should respond");
    assert_eq!(malformed_response.status(), StatusCode::BAD_REQUEST);
    assert_eq!(
        response_json(malformed_response).await["code"],
        "INVALID_JSON"
    );

    let invalid_query = send_json(&app, Method::GET, "/api/v1/tasks?enabled=maybe", None).await;
    assert_eq!(invalid_query.status(), StatusCode::BAD_REQUEST);
    assert_eq!(response_json(invalid_query).await["code"], "INVALID_QUERY");
}

#[tokio::test]
async fn rejects_cross_origin_and_missing_management_token() {
    let (app, _temp_dir) = test_app().await;
    let cross_origin = Request::builder()
        .method(Method::GET)
        .uri("/api/v1/tasks")
        .header(header::ORIGIN, "https://evil.example")
        .body(Body::empty())
        .expect("request should build");
    let response = app
        .clone()
        .oneshot(cross_origin)
        .await
        .expect("router should respond");
    assert_eq!(response.status(), StatusCode::FORBIDDEN);

    let missing_token = Request::builder()
        .method(Method::POST)
        .uri("/api/v1/tasks")
        .header(header::ORIGIN, "http://127.0.0.1:5173")
        .header(header::CONTENT_TYPE, "application/json")
        .body(Body::from(
            serde_json::to_vec(&script_task("blocked_task", "Blocked"))
                .expect("JSON should serialize"),
        ))
        .expect("request should build");
    let response = app
        .oneshot(missing_token)
        .await
        .expect("router should respond");
    assert_eq!(response.status(), StatusCode::FORBIDDEN);
    assert_eq!(response_json(response).await["code"], "FORBIDDEN");
}

#[tokio::test]
async fn list_supports_pagination_and_escaped_search() {
    let (app, _temp_dir) = test_app().await;
    for (id, name) in [
        ("sync_one", "Sync one"),
        ("sync_two", "Sync two"),
        ("other", "100% complete"),
    ] {
        let response = send_json(
            &app,
            Method::POST,
            "/api/v1/tasks",
            Some(script_task(id, name)),
        )
        .await;
        assert_eq!(response.status(), StatusCode::CREATED);
    }

    let first_page = send_json(
        &app,
        Method::GET,
        "/api/v1/tasks?q=sync&page=1&page_size=1",
        None,
    )
    .await;
    let first_page = response_json(first_page).await;
    assert_eq!(first_page["page"], 1);
    assert_eq!(first_page["page_size"], 1);
    assert_eq!(first_page["total"], 2);
    assert_eq!(first_page["items"].as_array().map(Vec::len), Some(1));

    let escaped = send_json(&app, Method::GET, "/api/v1/tasks?q=%25", None).await;
    let escaped = response_json(escaped).await;
    assert_eq!(escaped["total"], 1);
    assert_eq!(escaped["items"][0]["id"], "other");
}

#[tokio::test]
async fn tasks_survive_database_reconnect() {
    let temp_dir = TempDir::new().expect("temporary directory should be created");
    let database_path = temp_dir.path().join("task_pilot_test.db");

    let first_pool = connect_file(&database_path).await;
    let first_app = task_pilot_backend::app(first_pool.clone(), temp_dir.path().join("logs-first"))
        .await
        .expect("first app should start");
    let create_response = send_json(
        &first_app,
        Method::POST,
        "/api/v1/tasks",
        Some(script_task("persistent_task", "Persistent task")),
    )
    .await;
    assert_eq!(create_response.status(), StatusCode::CREATED);
    first_pool.close().await;
    drop(first_app);

    let second_pool = connect_file(&database_path).await;
    let second_app =
        task_pilot_backend::app(second_pool.clone(), temp_dir.path().join("logs-second"))
            .await
            .expect("second app should start");
    let get_response = send_json(
        &second_app,
        Method::GET,
        "/api/v1/tasks/persistent_task",
        None,
    )
    .await;
    assert_eq!(get_response.status(), StatusCode::OK);
    assert_eq!(response_json(get_response).await["name"], "Persistent task");
    second_pool.close().await;
}