vta-sdk 0.41.1

//! Canonical `device/*` request bodies.
//!
//! The #888 fold, applied to the family it did not reach. These methods used to
//! build their payloads as an inline `json!` plus a conditional insert per
//! optional member:
//!
//! ```ignore
//! let mut payload = json!({ "consumerKind": …, "displayName": … });
//! if let Some(p) = platform { payload["platform"] = json!(p); }
//! ```
//!
//! That shape is not wrong — the conditional insert is what kept `null` off the
//! wire — but it is unguarded and untestable. Unguarded because the invariant
//! lives in the shape of an `if let` rather than in an attribute, so nothing
//! checks it: the `vta-sdk` null census walks these structs and would have
//! caught `keys/create`, and it cannot see an inline map. Untestable because a
//! conformance witness has no type to point at, so it hand-writes the JSON and
//! stops tracking the producer the moment the producer changes.
//!
//! With a body struct both fall out for free: `skip_serializing_if` is what
//! keeps the member absent, the census enforces it, and the witness is built
//! rather than transcribed.
//!
//! Members mirror `device/*/0.1`. Only what the client can actually send is
//! modelled — `attestation` and `keyCustody` are in the schema but have no
//! producer here yet, and a field nothing sets is a claim the type should not
//! make.

use serde::{Deserialize, Serialize};
use serde_json::Value;

/// `device/register/0.1` — claim a `DeviceBinding` on the caller's ACL entry.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DeviceRegisterBody {
    /// The tagged `ConsumerKind` union (`{kind: "service", serviceKind: …}`).
    ///
    /// Stays a `Value` because the caller supplies it as one and the union has
    /// no Rust model here yet; modelling it is an API change, not a fold.
    pub consumer_kind: Value,
    pub display_name: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub platform: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub hpke_public_key: Option<String>,
}

/// `device/heartbeat/0.1` — refresh `lastSeenAt`, and `platform` if supplied.
///
/// Every member is optional: an empty body is the common case (a bare "still
/// here"), and it must serialize to `{}`, not to a map of nulls.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DeviceHeartbeatBody {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub platform: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub vault_seq: Option<u64>,
    /// Namespaced extension members (SPEC §4.5.1). Carries
    /// `org.openvtc.device-name` when the device is correcting its own
    /// `displayName`, which registration set once and nothing else updates.
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub ext: Option<Value>,
}

/// Extension member a device uses to correct its own `displayName` on a
/// heartbeat. Its value is `{ "displayName": "…" }`.
///
/// Reverse-DNS namespaced per SPEC §4.5.1, named the way this ecosystem already
/// names its extensions (`org.openvtc.vault-session`,
/// `org.openvtc.authorization-context`). **Defined once, here**, and imported by
/// the VTA that honours it: the two sides otherwise agree by string, and a typo
/// on either would be a rename that silently never happens.
///
/// # Why an extension and not `device/register`
///
/// `displayName` exists "to help a human pick their own laptop out of a list"
/// (dtgwg `device/register/0.2` §Security & Privacy) and is set exactly once, at
/// registration, because re-registration is **intentionally** refused
/// (`device/register:alreadyRegistered`). Nothing in the device family updates
/// it, so a renamed machine keeps announcing a name that no longer identifies
/// it. Heartbeat is where the spec already puts metadata drift — `platform` is
/// defined there as "updated platform descriptor if it changed since
/// registration" — and `ext` is the slot it provides for the rest.
pub const EXT_DEVICE_NAME: &str = "org.openvtc.device-name";

/// The `ext` member that corrects this device's `displayName` — see
/// [`EXT_DEVICE_NAME`].
///
/// A constructor rather than a literal at the call site, so the key is written
/// once on this side of the wire.
#[must_use]
pub fn device_name_ext(display_name: &str) -> Value {
    serde_json::json!({ EXT_DEVICE_NAME: { "displayName": display_name } })
}

/// `device/disable/0.1` — disable a device by id; the record is kept.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DeviceDisableBody {
    pub device_id: String,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub reason: Option<String>,
}

/// `device/wipe/0.1` — remote-wipe a compromised or lost device.
///
/// `scope` and `reason` are both required by the spec: a wipe with no recorded
/// reason is an audit gap, and the schema refuses one.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DeviceWipeBody {
    pub device_id: String,
    /// `cache` | `cache-and-keys` | `full`.
    pub scope: String,
    pub reason: String,
}

/// The device's opaque push handle.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct WakeHandle {
    pub gateway: String,
    pub handle: String,
}

/// `device/set-wake/0.1` — convey the device's `WakeHandle`.
#[derive(Debug, Clone, Default, Serialize, Deserialize)]
#[serde(rename_all = "camelCase")]
pub struct DeviceSetWakeBody {
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub wake_handle: Option<WakeHandle>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub suggested_triggers: Option<Vec<String>>,
}

#[cfg(test)]
mod tests {
    use super::*;

    /// The property the fold exists to make enforceable: an unset optional is
    /// absent, so a bare heartbeat is `{}` rather than a map of nulls.
    ///
    /// The old inline builder got this right by construction. Nothing checked
    /// it, and `keys/create` is what that costs when someone later reaches for
    /// a struct instead (#919).
    #[test]
    fn a_bare_heartbeat_is_an_empty_object() {
        assert_eq!(
            serde_json::to_value(DeviceHeartbeatBody::default()).expect("serialises"),
            serde_json::json!({})
        );
    }

    /// The name correction rides in the spec's own extension slot, under the
    /// key the VTA matches on.
    #[test]
    fn a_named_heartbeat_carries_the_device_name_extension() {
        let body = DeviceHeartbeatBody {
            platform: None,
            vault_seq: None,
            ext: Some(device_name_ext("OpenVTC on new-host (default)")),
        };
        assert_eq!(
            serde_json::to_value(&body).expect("serialises"),
            serde_json::json!({
                "ext": {
                    "org.openvtc.device-name": {
                        "displayName": "OpenVTC on new-host (default)"
                    }
                }
            })
        );
    }

    /// The `ext` key has to satisfy the schema's reverse-DNS pattern
    /// (`^[a-z][a-z0-9-]*(\.[a-z0-9-]+)+$`) or a conforming maintainer rejects
    /// the whole heartbeat — taking `lastSeenAt` down with it, so a bad key here
    /// is a liveness bug, not a cosmetic one.
    #[test]
    fn the_extension_key_matches_the_schema_pattern() {
        let segments: Vec<&str> = EXT_DEVICE_NAME.split('.').collect();
        assert!(segments.len() >= 2, "{EXT_DEVICE_NAME} needs a namespace");
        assert!(
            EXT_DEVICE_NAME.starts_with(|c: char| c.is_ascii_lowercase()),
            "{EXT_DEVICE_NAME} must start with a lowercase letter"
        );
        for segment in segments {
            assert!(
                !segment.is_empty(),
                "{EXT_DEVICE_NAME} has an empty segment"
            );
            assert!(
                segment
                    .chars()
                    .all(|c| c.is_ascii_lowercase() || c.is_ascii_digit() || c == '-'),
                "{segment} may only hold [a-z0-9-]"
            );
        }
    }

    #[test]
    fn an_unset_register_member_is_absent() {
        let minimal = DeviceRegisterBody {
            consumer_kind: serde_json::json!({"kind": "companion", "formFactor": "desktop"}),
            display_name: "laptop".into(),
            platform: None,
            hpke_public_key: None,
        };
        assert_eq!(
            serde_json::to_value(&minimal).expect("serialises"),
            serde_json::json!({
                "consumerKind": {"kind": "companion", "formFactor": "desktop"},
                "displayName": "laptop",
            })
        );
    }

    /// Set members still reach the wire under their canonical camelCase names —
    /// the skip must not be reachable for `Some`.
    #[test]
    fn set_members_serialise_camel_case() {
        let full = DeviceRegisterBody {
            consumer_kind: serde_json::json!({"kind": "service", "serviceKind": "ai-agent"}),
            display_name: "agent".into(),
            platform: Some("macos".into()),
            hpke_public_key: Some("zHpke".into()),
        };
        let v = serde_json::to_value(&full).expect("serialises");
        assert_eq!(v.get("platform").and_then(Value::as_str), Some("macos"));
        assert_eq!(
            v.get("hpkePublicKey").and_then(Value::as_str),
            Some("zHpke")
        );
    }

    #[test]
    fn a_wake_handle_nests_under_its_camel_case_member() {
        let body = DeviceSetWakeBody {
            wake_handle: Some(WakeHandle {
                gateway: "apns".into(),
                handle: "opaque".into(),
            }),
            suggested_triggers: Some(vec!["message".into()]),
        };
        assert_eq!(
            serde_json::to_value(&body).expect("serialises"),
            serde_json::json!({
                "wakeHandle": {"gateway": "apns", "handle": "opaque"},
                "suggestedTriggers": ["message"],
            })
        );
    }
}