//! Integration tests for k8shost API Server
//!
//! These tests verify end-to-end functionality including:
//! - Pod lifecycle (create, get, list, delete)
//! - Service exposure and cluster IP allocation
//! - Multi-tenant isolation
//! - IAM authentication and authorization

use k8shost_proto::{
    pod_service_client::PodServiceClient, service_service_client::ServiceServiceClient,
    node_service_client::NodeServiceClient, Container, ContainerPort, CreatePodRequest,
    CreateServiceRequest, DeletePodRequest, DeleteServiceRequest, GetPodRequest,
    GetServiceRequest, ListPodsRequest, ListServicesRequest, ObjectMeta, Pod, PodSpec, Service,
    ServicePort, ServiceSpec,
};
use std::collections::HashMap;
use tonic::metadata::MetadataValue;
use tonic::transport::Channel;
use tonic::{Request, Status};

// Type alias for intercepted service with our authentication closure
type AuthInterceptor = fn(Request<()>) -> Result<Request<()>, Status>;

/// Test configuration
struct TestConfig {
    server_addr: String,
    flaredb_addr: String,
    iam_addr: String,
}

impl TestConfig {
    fn from_env() -> Self {
        Self {
            server_addr: std::env::var("K8SHOST_SERVER_ADDR")
                .unwrap_or_else(|_| "http://127.0.0.1:6443".to_string()),
            flaredb_addr: std::env::var("FLAREDB_PD_ADDR")
                .unwrap_or_else(|_| "127.0.0.1:2379".to_string()),
            iam_addr: std::env::var("IAM_SERVER_ADDR")
                .unwrap_or_else(|_| "http://127.0.0.1:50051".to_string()),
        }
    }
}

/// Helper to create an authenticated gRPC client with bearer token
async fn create_authenticated_pod_client(
    token: &str,
) -> Result<PodServiceClient<tonic::service::interceptor::InterceptedService<Channel, impl FnMut(Request<()>) -> Result<Request<()>, Status> + Clone>>, Box<dyn std::error::Error>> {
    let config = TestConfig::from_env();
    let channel = Channel::from_shared(config.server_addr.clone())?
        .connect()
        .await?;

    let token_value = format!("Bearer {}", token);
    let token_metadata: MetadataValue<_> = token_value.parse()?;

    // Create a channel-based client with interceptor
    let client = PodServiceClient::with_interceptor(
        channel,
        move |mut req: Request<()>| -> Result<Request<()>, Status> {
            req.metadata_mut()
                .insert("authorization", token_metadata.clone());
            Ok(req)
        },
    );

    Ok(client)
}

/// Helper to create an authenticated service client
async fn create_authenticated_service_client(
    token: &str,
) -> Result<ServiceServiceClient<tonic::service::interceptor::InterceptedService<Channel, impl FnMut(Request<()>) -> Result<Request<()>, Status> + Clone>>, Box<dyn std::error::Error>> {
    let config = TestConfig::from_env();
    let channel = Channel::from_shared(config.server_addr.clone())?
        .connect()
        .await?;

    let token_value = format!("Bearer {}", token);
    let token_metadata: MetadataValue<_> = token_value.parse()?;

    let client = ServiceServiceClient::with_interceptor(
        channel,
        move |mut req: Request<()>| -> Result<Request<()>, Status> {
            req.metadata_mut()
                .insert("authorization", token_metadata.clone());
            Ok(req)
        },
    );

    Ok(client)
}

/// Mock token generator for testing
/// In a real setup, this would call IAM to issue tokens
fn generate_mock_token(org_id: &str, project_id: &str, principal: &str) -> String {
    // For testing purposes, we'll use a simple format
    // In production, this should be a proper JWT from IAM
    format!("mock-token-{}-{}-{}", org_id, project_id, principal)
}

/// Helper to create a test pod spec
fn create_test_pod_spec(
    name: &str,
    namespace: &str,
    org_id: &str,
    project_id: &str,
) -> Pod {
    Pod {
        metadata: Some(ObjectMeta {
            name: name.to_string(),
            namespace: Some(namespace.to_string()),
            uid: None,
            resource_version: None,
            creation_timestamp: None,
            labels: HashMap::from([("app".to_string(), "test".to_string())]),
            annotations: HashMap::new(),
            org_id: Some(org_id.to_string()),
            project_id: Some(project_id.to_string()),
        }),
        spec: Some(PodSpec {
            containers: vec![Container {
                name: "nginx".to_string(),
                image: "nginx:latest".to_string(),
                command: vec![],
                args: vec![],
                ports: vec![ContainerPort {
                    name: Some("http".to_string()),
                    container_port: 80,
                    protocol: Some("TCP".to_string()),
                }],
                env: vec![],
            }],
            restart_policy: Some("Always".to_string()),
            node_name: None,
        }),
        status: None,
    }
}

/// Helper to create a test service spec
fn create_test_service_spec(
    name: &str,
    namespace: &str,
    org_id: &str,
    project_id: &str,
) -> Service {
    Service {
        metadata: Some(ObjectMeta {
            name: name.to_string(),
            namespace: Some(namespace.to_string()),
            uid: None,
            resource_version: None,
            creation_timestamp: None,
            labels: HashMap::new(),
            annotations: HashMap::new(),
            org_id: Some(org_id.to_string()),
            project_id: Some(project_id.to_string()),
        }),
        spec: Some(ServiceSpec {
            ports: vec![ServicePort {
                name: Some("http".to_string()),
                port: 80,
                target_port: Some(80),
                protocol: Some("TCP".to_string()),
            }],
            selector: HashMap::from([("app".to_string(), "test".to_string())]),
            cluster_ip: None,
            r#type: Some("ClusterIP".to_string()),
        }),
        status: None,
    }
}

/// Test 1: Pod Lifecycle
/// Create, get, list, and delete a pod
#[tokio::test]
#[ignore] // Run with --ignored flag when server is running
async fn test_pod_lifecycle() -> Result<(), Box<dyn std::error::Error>> {
    // Generate test token
    let token = generate_mock_token("org-test", "project-test", "user-1");
    let mut client = create_authenticated_pod_client(&token).await?;

    // Create a pod
    let pod_name = "test-pod-lifecycle";
    let namespace = "default";
    let pod = create_test_pod_spec(pod_name, namespace, "org-test", "project-test");

    let create_response = client
        .create_pod(Request::new(CreatePodRequest { pod: Some(pod) }))
        .await?;

    let created_pod = create_response
        .into_inner()
        .pod
        .expect("Created pod should be returned");

    println!("Created pod: {:?}", created_pod.metadata);

    // Verify pod has UID and creation timestamp
    assert!(created_pod.metadata.as_ref().unwrap().uid.is_some());
    assert!(created_pod
        .metadata
        .as_ref()
        .unwrap()
        .creation_timestamp
        .is_some());

    // Get the pod
    let get_response = client
        .get_pod(Request::new(GetPodRequest {
            name: pod_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await?;

    let fetched_pod = get_response
        .into_inner()
        .pod
        .expect("Fetched pod should be returned");

    assert_eq!(
        &fetched_pod.metadata.as_ref().unwrap().name,
        pod_name
    );

    // List pods
    let list_response = client
        .list_pods(Request::new(ListPodsRequest {
            namespace: Some(namespace.to_string()),
            label_selector: HashMap::new(),
        }))
        .await?;

    let pods = list_response.into_inner().items;
    assert!(
        pods.iter()
            .any(|p| {
                if let Some(meta) = &p.metadata {
                    return &meta.name == pod_name;
                }
                false
            }),
        "Created pod should be in the list"
    );

    // Delete the pod
    let delete_response = client
        .delete_pod(Request::new(DeletePodRequest {
            name: pod_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await?;

    assert!(
        delete_response.into_inner().success,
        "Pod should be deleted successfully"
    );

    // Verify pod is deleted (get should fail)
    let get_result = client
        .get_pod(Request::new(GetPodRequest {
            name: pod_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await;

    assert!(
        get_result.is_err(),
        "Get should fail after pod is deleted"
    );

    Ok(())
}

/// Test 2: Service Exposure
/// Create a service and verify cluster IP allocation
#[tokio::test]
#[ignore] // Run with --ignored flag when server is running
async fn test_service_exposure() -> Result<(), Box<dyn std::error::Error>> {
    let token = generate_mock_token("org-test", "project-test", "user-1");
    let mut client = create_authenticated_service_client(&token).await?;

    // Create a service
    let service_name = "test-service-exposure";
    let namespace = "default";
    let service = create_test_service_spec(service_name, namespace, "org-test", "project-test");

    let create_response = client
        .create_service(Request::new(CreateServiceRequest {
            service: Some(service),
        }))
        .await?;

    let created_service = create_response
        .into_inner()
        .service
        .expect("Created service should be returned");

    println!("Created service: {:?}", created_service.metadata);

    // Verify service has cluster IP allocated
    assert!(
        created_service
            .spec
            .as_ref()
            .unwrap()
            .cluster_ip
            .is_some(),
        "Cluster IP should be allocated"
    );

    let cluster_ip = created_service.spec.as_ref().unwrap().cluster_ip.clone().unwrap();
    println!("Allocated cluster IP: {}", cluster_ip);

    // Get the service
    let get_response = client
        .get_service(Request::new(GetServiceRequest {
            name: service_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await?;

    let fetched_service = get_response
        .into_inner()
        .service
        .expect("Fetched service should be returned");

    assert_eq!(
        &fetched_service.metadata.as_ref().unwrap().name,
        service_name
    );
    assert_eq!(
        fetched_service.spec.as_ref().unwrap().cluster_ip,
        Some(cluster_ip)
    );

    // List services
    let list_response = client
        .list_services(Request::new(ListServicesRequest {
            namespace: Some(namespace.to_string()),
        }))
        .await?;

    let services = list_response.into_inner().items;
    assert!(
        services
            .iter()
            .any(|s| {
                if let Some(meta) = &s.metadata {
                    return &meta.name == service_name;
                }
                false
            }),
        "Created service should be in the list"
    );

    // Delete the service
    let delete_response = client
        .delete_service(Request::new(DeleteServiceRequest {
            name: service_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await?;

    assert!(
        delete_response.into_inner().success,
        "Service should be deleted successfully"
    );

    Ok(())
}

/// Test 3: Multi-Tenant Isolation
/// Verify that resources from one tenant cannot be accessed by another
#[tokio::test]
#[ignore] // Run with --ignored flag when server is running
async fn test_multi_tenant_isolation() -> Result<(), Box<dyn std::error::Error>> {
    // Create pod in org-A with token-A
    let token_a = generate_mock_token("org-a", "project-a", "user-a");
    let mut client_a = create_authenticated_pod_client(&token_a).await?;

    let pod_name = "test-isolation-pod";
    let namespace = "default";
    let pod = create_test_pod_spec(pod_name, namespace, "org-a", "project-a");

    let create_response = client_a
        .create_pod(Request::new(CreatePodRequest { pod: Some(pod) }))
        .await?;

    println!(
        "Created pod in org-a: {:?}",
        create_response.into_inner().pod
    );

    // Try to get the pod with token-B (different org)
    let token_b = generate_mock_token("org-b", "project-b", "user-b");
    let mut client_b = create_authenticated_pod_client(&token_b).await?;

    let get_result = client_b
        .get_pod(Request::new(GetPodRequest {
            name: pod_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await;

    // Should return NotFound because the pod belongs to org-a, not org-b
    assert!(
        get_result.is_err(),
        "Token from org-b should not be able to access pod from org-a"
    );

    if let Err(status) = get_result {
        assert_eq!(
            status.code(),
            tonic::Code::NotFound,
            "Should return NotFound status"
        );
    }

    // List pods with token-B should return empty list
    let list_response = client_b
        .list_pods(Request::new(ListPodsRequest {
            namespace: Some(namespace.to_string()),
            label_selector: HashMap::new(),
        }))
        .await?;

    let pods = list_response.into_inner().items;
    assert!(
        !pods
            .iter()
            .any(|p| {
                if let Some(meta) = &p.metadata {
                    return &meta.name == pod_name;
                }
                false
            }),
        "Token from org-b should not see pods from org-a"
    );

    // Cleanup: delete pod with token-A
    let delete_response = client_a
        .delete_pod(Request::new(DeletePodRequest {
            name: pod_name.to_string(),
            namespace: namespace.to_string(),
        }))
        .await?;

    assert!(delete_response.into_inner().success);

    Ok(())
}

/// Test 4: Invalid Token Handling
/// Verify that requests without valid tokens are rejected
#[tokio::test]
#[ignore] // Run with --ignored flag when server is running
async fn test_invalid_token_handling() -> Result<(), Box<dyn std::error::Error>> {
    // Try to create client with invalid token
    let invalid_token = "invalid-token-xyz";
    let mut client = create_authenticated_pod_client(invalid_token).await?;

    let pod_name = "test-invalid-token-pod";
    let namespace = "default";
    let pod = create_test_pod_spec(pod_name, namespace, "org-test", "project-test");

    // Attempt to create pod should fail with Unauthenticated
    let create_result = client
        .create_pod(Request::new(CreatePodRequest { pod: Some(pod) }))
        .await;

    assert!(
        create_result.is_err(),
        "Request with invalid token should fail"
    );

    if let Err(status) = create_result {
        assert_eq!(
            status.code(),
            tonic::Code::Unauthenticated,
            "Should return Unauthenticated status"
        );
    }

    Ok(())
}

/// Test 5: Missing Authorization Header
/// Verify that requests without Authorization header are rejected
#[tokio::test]
#[ignore] // Run with --ignored flag when server is running
async fn test_missing_authorization() -> Result<(), Box<dyn std::error::Error>> {
    let config = TestConfig::from_env();
    let channel = Channel::from_shared(config.server_addr.clone())?
        .connect()
        .await?;

    let mut client = PodServiceClient::new(channel);

    let pod_name = "test-no-auth-pod";
    let namespace = "default";
    let pod = create_test_pod_spec(pod_name, namespace, "org-test", "project-test");

    // Attempt to create pod without authorization header should fail
    let create_result = client
        .create_pod(Request::new(CreatePodRequest { pod: Some(pod) }))
        .await;

    assert!(
        create_result.is_err(),
        "Request without authorization should fail"
    );

    if let Err(status) = create_result {
        assert_eq!(
            status.code(),
            tonic::Code::Unauthenticated,
            "Should return Unauthenticated status"
        );
    }

    Ok(())
}