vta-service 0.5.1

//! Helpers for the `WEBVH_SERVER` / `WEBVH_PATH` template variables —
//! the two "transport metadata" vars that control where the VTA
//! publishes the integration's `did.jsonl` log. These are *not*
//! document content; they never reach the template renderer.
//!
//! The rest of the provision-integration flow treats webvh-hosted and
//! serverless integrations uniformly; these two helpers are the only
//! places that know about the `WEBVH_*` var names.

use std::collections::BTreeMap;

use serde_json::Value;

use crate::error::AppError;

/// Read the optional `WEBVH_SERVER` template var, validate it against
/// the registered-server catalogue, and return the resolved id.
///
/// Returns `Ok(None)` when the var is absent, JSON-null, or the empty
/// string (treated as "not set"). Returns `Err(AppError::NotFound)` when
/// the var names an id that isn't registered with this VTA — caller
/// surfaces that to the operator before any state is written.
pub(super) async fn resolve_webvh_server(
    template_vars: &BTreeMap<String, Value>,
    webvh_ks: &crate::store::KeyspaceHandle,
) -> Result<Option<String>, AppError> {
    let raw = match template_vars.get("WEBVH_SERVER") {
        None | Some(Value::Null) => return Ok(None),
        Some(Value::String(s)) => s,
        Some(other) => {
            let actual = match other {
                Value::Bool(_) => "bool",
                Value::Number(_) => "number",
                Value::Array(_) => "array",
                Value::Object(_) => "object",
                _ => "non-string",
            };
            return Err(AppError::Validation(format!(
                "WEBVH_SERVER must be a string (registered webvh-server id), got {actual}"
            )));
        }
    };
    let id = raw.trim();
    if id.is_empty() {
        return Ok(None);
    }
    if crate::webvh_store::get_server(webvh_ks, id)
        .await?
        .is_none()
    {
        return Err(AppError::NotFound(format!(
            "WEBVH_SERVER '{id}' is not a registered webvh hosting server on this VTA \
             — register it via `vta webvh add-server` first, or omit `WEBVH_SERVER` \
             to self-host at the URL"
        )));
    }
    Ok(Some(id.to_string()))
}

/// Remove and return the optional `WEBVH_PATH` template var.
///
/// `WEBVH_PATH` is transport metadata — it tells the webvh server which
/// path to allocate when the VTA calls `POST /api/dids`. It is removed
/// from `template_vars` before the renderer sees the map so that a
/// template author never accidentally picks it up as document content.
///
/// `Ok(None)` when the var is absent or JSON-null. `Ok(Some(path))` when
/// it is a non-empty string. Empty strings and non-string types fail
/// loud — the operator set the var intentionally and a silent fallback
/// would mask a typo.
pub(super) fn take_webvh_path(
    template_vars: &mut BTreeMap<String, Value>,
) -> Result<Option<String>, AppError> {
    let removed = match template_vars.remove("WEBVH_PATH") {
        None | Some(Value::Null) => return Ok(None),
        Some(v) => v,
    };
    let s = match removed {
        Value::String(s) => s,
        _ => {
            return Err(AppError::Validation(
                "WEBVH_PATH must be a non-empty string".into(),
            ));
        }
    };
    let trimmed = s.trim();
    if trimmed.is_empty() {
        return Err(AppError::Validation(
            "WEBVH_PATH must be a non-empty string".into(),
        ));
    }
    Ok(Some(trimmed.to_string()))
}