// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.

//! Helper macros for implementing the FFI API for metric types.

/// Get a metric object by ID from the corresponding map.
///
/// # Arguments
///
/// * `$map` - The name of the hash map within `metrics::__glean_metric_maps`
///            as generated by glean_parser.
/// * `$id`  - The ID of the metric to get.
macro_rules! metric_get {
    ($map:ident, $id:ident) => {
        match $crate::metrics::__glean_metric_maps::$map.get(&$id.into()) {
            Some(metric) => metric,
            None => panic!("No metric for id {}", $id),
        }
    };
}

/// Test whether a value is stored for the metric identified by its ID.
///
/// # Arguments
///
/// * `$map`     - The name of the hash map within `metrics::__glean_metric_maps`
///                as generated by glean_parser.
/// * `$id`      - The ID of the metric to get.
/// * `$storage` - the storage name to look into.
macro_rules! test_has {
    ($map:ident, $id:ident, $storage:ident) => {{
        let metric = metric_get!($map, $id);
        let storage = if $storage.is_empty() {
            None
        } else {
            Some($storage.to_utf8())
        };
        metric.test_get_value(storage.as_deref()).is_some()
    }};
}

/// Get the currently stored value for the metric identified by its ID.
///
/// # Arguments
///
/// * `$map`     - The name of the hash map within `metrics::__glean_metric_maps`
///                as generated by glean_parser.
/// * `$id`      - The ID of the metric to get.
/// * `$storage` - the storage name to look into.
macro_rules! test_get {
    ($map:ident, $id:ident, $storage:ident) => {{
        let metric = metric_get!($map, $id);
        let storage = if $storage.is_empty() {
            None
        } else {
            Some($storage.to_utf8())
        };
        metric.test_get_value(storage.as_deref()).unwrap()
    }};
}