use wip_https::http::StatusCode;
use wip_https::wip_protocol::{
    FetchInterfaceRequest, FetchInterfaceResponse, FetchRequest, INTERFACE_FORMAT_V1,
    InterfaceDescriptor, Object, ProtocolError, ProtocolErrorCode,
};
use wip_https::{
    BatchMethod, BatchRequest, BatchRequestItem, BatchRequestKind, BatchResponse,
    BatchResponseItem, BatchSuccess, ClientResponseError, DecodedResponse, Endpoint,
    InvalidResponseKind, Limits, ResourceLimitKind, decode_batch_request, decode_batch_response,
    encode_batch_error_response, encode_batch_request, encode_batch_resource_limit_error_response,
    encode_batch_response,
};

fn limits() -> Limits {
    Limits::new(100_000, 100_000, 64, 4).unwrap()
}

fn request() -> BatchRequest {
    BatchRequest {
        requests: vec![
            BatchRequestItem {
                id: "object".into(),
                request: BatchRequestKind::Fetch(FetchRequest {
                    path: "/item".into(),
                }),
            },
            BatchRequestItem {
                id: "interface".into(),
                request: BatchRequestKind::FetchInterface(FetchInterfaceRequest {
                    interface: "interface-v1".into(),
                }),
            },
        ],
    }
}

#[test]
fn batch_round_trips_by_unique_id_with_item_failures_and_validators() {
    let request = request();
    let endpoint = Endpoint::parse("https://example.test/wip").unwrap();
    let encoded_request = encode_batch_request(&endpoint, &request, limits()).unwrap();
    assert_eq!(encoded_request.uri().path(), "/wip/v1/batch");
    assert_eq!(encoded_request.headers()["accept"], "application/json");
    assert_eq!(
        decode_batch_request(encoded_request.body(), limits()).unwrap(),
        request
    );

    let response = BatchResponse {
        responses: vec![
            BatchResponseItem {
                id: "interface".into(),
                outcome: Err(ProtocolError {
                    code: ProtocolErrorCode::InterfaceNotFound,
                    message: "gone".into(),
                }),
            },
            BatchResponseItem {
                id: "object".into(),
                outcome: Ok(BatchSuccess::Fetch(Object {
                    name: "item".into(),
                    description: None,
                    interfaces: vec![],
                    r#ref: None,
                    validator: Some(vec![0, 1, 2, 255]),
                })),
            },
        ],
    };
    let encoded = encode_batch_response(&request, &response, limits()).unwrap();
    assert_eq!(encoded.status(), StatusCode::OK);
    assert!(
        std::str::from_utf8(encoded.body())
            .unwrap()
            .contains("AAEC/w==")
    );
    assert_eq!(
        decode_batch_response(&request, &encoded, limits()).unwrap(),
        DecodedResponse::Success(response)
    );
}

#[test]
fn batch_interface_validator_round_trips_in_item_body() {
    let request = BatchRequest {
        requests: vec![BatchRequestItem {
            id: "interface".into(),
            request: BatchRequestKind::FetchInterface(FetchInterfaceRequest {
                interface: "interface-v1".into(),
            }),
        }],
    };
    let response = BatchResponse {
        responses: vec![BatchResponseItem {
            id: "interface".into(),
            outcome: Ok(BatchSuccess::FetchInterface(FetchInterfaceResponse {
                interface: "interface-v1".into(),
                descriptor: InterfaceDescriptor {
                    format: INTERFACE_FORMAT_V1.into(),
                    documentation: None,
                    types: vec![],
                    operations: vec![],
                },
                validator: Some(vec![255, 254, 253]),
            })),
        }],
    };
    let encoded = encode_batch_response(&request, &response, limits()).unwrap();
    assert!(
        std::str::from_utf8(encoded.body())
            .unwrap()
            .contains("//79")
    );
    assert_eq!(
        decode_batch_response(&request, &encoded, limits()).unwrap(),
        DecodedResponse::Success(response)
    );
}

#[test]
fn malformed_known_method_arguments_are_item_local() {
    let body = br#"{
        "requests": [
            {"id":"valid","method":"fetch","arguments":{"path":"/item"}},
            {"id":"invalid","method":"fetch_tree","arguments":{"path":"/","depth":"deep","limit":1}}
        ]
    }"#;
    let decoded = decode_batch_request(body, limits()).unwrap();
    assert!(matches!(
        decoded.requests[0].request,
        BatchRequestKind::Fetch(_)
    ));
    let invalid = match &decoded.requests[1].request {
        BatchRequestKind::Invalid { method, error } => {
            assert_eq!(*method, BatchMethod::FetchTree);
            assert_eq!(error.code, ProtocolErrorCode::InvalidRequest);
            error.clone()
        }
        other => panic!("expected item-local invalid request, got {other:?}"),
    };

    let response = BatchResponse {
        responses: vec![
            BatchResponseItem {
                id: "valid".into(),
                outcome: Ok(BatchSuccess::Fetch(Object {
                    name: "item".into(),
                    description: None,
                    interfaces: vec![],
                    r#ref: None,
                    validator: None,
                })),
            },
            BatchResponseItem {
                id: "invalid".into(),
                outcome: Err(invalid),
            },
        ],
    };
    let encoded = encode_batch_response(&decoded, &response, limits()).unwrap();
    assert_eq!(encoded.status(), StatusCode::OK);
    assert_eq!(
        decode_batch_response(&decoded, &encoded, limits()).unwrap(),
        DecodedResponse::Success(response)
    );
}

#[test]
fn invalid_batch_envelopes_are_rejected_at_top_level() {
    assert!(decode_batch_request(br#"{}"#, limits()).is_err());

    let malformed_item = br#"{
        "requests": [
            {"id":"item","method":"fetch","arguments":{"path":"/"},"extra":true}
        ]
    }"#;
    assert!(decode_batch_request(malformed_item, limits()).is_err());

    let duplicate = br#"{
        "requests": [
            {"id":"same","method":"fetch","arguments":{"path":"/a"}},
            {"id":"same","method":"fetch","arguments":{"path":"/b"}}
        ]
    }"#;
    assert!(decode_batch_request(duplicate, limits()).is_err());

    let operation = br#"{
        "requests": [
            {"id":"call","method":"call_operation","arguments":{}}
        ]
    }"#;
    assert!(decode_batch_request(operation, limits()).is_err());

    let too_many = Limits::new(100_000, 100_000, 64, 1).unwrap();
    assert!(decode_batch_request(duplicate, too_many).is_err());
}

#[test]
fn batch_resource_limits_use_413_or_422_and_never_429() {
    let error = ProtocolError {
        code: ProtocolErrorCode::ResourceLimitExceeded,
        message: "bounded".into(),
    };
    for (kind, status) in [
        (
            ResourceLimitKind::RepresentationBytes,
            StatusCode::PAYLOAD_TOO_LARGE,
        ),
        (ResourceLimitKind::Logical, StatusCode::UNPROCESSABLE_ENTITY),
    ] {
        let encoded = encode_batch_resource_limit_error_response(&error, kind, limits()).unwrap();
        assert_eq!(encoded.status(), status);
        assert_ne!(encoded.status(), StatusCode::TOO_MANY_REQUESTS);
        assert_eq!(
            decode_batch_response(&request(), &encoded, limits()).unwrap(),
            DecodedResponse::ProtocolFailure {
                error: error.clone(),
                status_mismatch: None,
            }
        );
    }
}

#[test]
fn batch_success_body_requires_exactly_http_200() {
    let request = request();
    let response = BatchResponse {
        responses: vec![
            BatchResponseItem {
                id: "object".into(),
                outcome: Ok(BatchSuccess::Fetch(Object {
                    name: "item".into(),
                    description: None,
                    interfaces: vec![],
                    r#ref: None,
                    validator: None,
                })),
            },
            BatchResponseItem {
                id: "interface".into(),
                outcome: Err(ProtocolError {
                    code: ProtocolErrorCode::InterfaceNotFound,
                    message: "gone".into(),
                }),
            },
        ],
    };
    let encoded = encode_batch_response(&request, &response, limits()).unwrap();
    for status in [StatusCode::CREATED, StatusCode::ACCEPTED] {
        let mut noncanonical = encoded.clone();
        *noncanonical.status_mut() = status;
        assert!(matches!(
            decode_batch_response(&request, &noncanonical, limits()).unwrap_err(),
            ClientResponseError::InvalidResponse { .. }
        ));
    }
}

#[test]
fn top_level_batch_errors_use_the_batch_allowed_code_set() {
    let invalid = ProtocolError {
        code: ProtocolErrorCode::InvalidRequest,
        message: "bad envelope".into(),
    };
    let encoded = encode_batch_error_response(&invalid, limits()).unwrap();
    assert_eq!(
        decode_batch_response(&request(), &encoded, limits()).unwrap(),
        DecodedResponse::ProtocolFailure {
            error: invalid,
            status_mismatch: None,
        }
    );

    let not_found = wip_https::http::Response::builder()
        .status(StatusCode::NOT_FOUND)
        .header("content-type", "application/json; charset=utf-8")
        .body(br#"{"error":{"code":"not_found","message":"not a batch failure"}}"#.to_vec())
        .unwrap();
    assert!(matches!(
        decode_batch_response(&request(), &not_found, limits()).unwrap_err(),
        ClientResponseError::InvalidResponse {
            kind: InvalidResponseKind::InvalidBatch,
            ..
        }
    ));
}

#[test]
fn unsupported_batch_descriptor_waits_for_envelope_correlation() {
    let duplicate = wip_https::http::Response::builder()
        .status(StatusCode::OK)
        .header("content-type", "application/json; charset=utf-8")
        .body(
            br#"{"responses":[{"id":"interface","result":{"interface":"interface-v1","descriptor":{"format":"wip-interface/2","future":true}}},{"id":"interface","result":{"interface":"interface-v1","descriptor":{"format":"wip-interface/2"}}}]}"#
                .to_vec(),
        )
        .unwrap();
    assert!(matches!(
        decode_batch_response(&request(), &duplicate, limits()).unwrap_err(),
        ClientResponseError::InvalidResponse {
            kind: InvalidResponseKind::InvalidBatch,
            ..
        }
    ));

    let missing = wip_https::http::Response::builder()
        .status(StatusCode::OK)
        .header("content-type", "application/json; charset=utf-8")
        .body(
            br#"{"responses":[{"id":"interface","result":{"interface":"interface-v1","descriptor":{"format":"wip-interface/2"}}}]}"#
                .to_vec(),
        )
        .unwrap();
    assert!(matches!(
        decode_batch_response(&request(), &missing, limits()).unwrap_err(),
        ClientResponseError::InvalidResponse {
            kind: InvalidResponseKind::InvalidBatch,
            ..
        }
    ));

    let request = BatchRequest {
        requests: vec![BatchRequestItem {
            id: "interface".into(),
            request: BatchRequestKind::FetchInterface(FetchInterfaceRequest {
                interface: "interface-v1".into(),
            }),
        }],
    };
    assert!(matches!(
        decode_batch_response(&request, &missing, limits()).unwrap_err(),
        ClientResponseError::UnsupportedDescriptorFormat { format }
            if format == "wip-interface/2"
    ));
}

#[test]
fn batch_response_must_have_exactly_the_requested_ids() {
    let request = request();
    let missing = BatchResponse {
        responses: vec![BatchResponseItem {
            id: "object".into(),
            outcome: Ok(BatchSuccess::Fetch(Object {
                name: "item".into(),
                description: None,
                interfaces: vec![],
                r#ref: None,
                validator: None,
            })),
        }],
    };
    assert!(encode_batch_response(&request, &missing, limits()).is_err());
}