bevy_brp_mcp 0.22.2

use bevy_brp_mcp_macros::ResultStruct;
use bevy_brp_mcp_macros::ToolFn;
use serde::Deserialize;
use serde::Serialize;

use super::TracingLevel;
use crate::error::Result;
use crate::tool::HandlerContext;
use crate::tool::HandlerResult;
use crate::tool::NoParams;
use crate::tool::ToolFn;
use crate::tool::ToolResult;

#[derive(Debug, Clone, Copy, Serialize, Deserialize)]
#[serde(from = "bool", into = "bool")]
enum TraceLogFile {
    Missing,
    Present,
}

impl From<bool> for TraceLogFile {
    fn from(value: bool) -> Self { if value { Self::Present } else { Self::Missing } }
}

impl From<TraceLogFile> for bool {
    fn from(value: TraceLogFile) -> Self { matches!(value, TraceLogFile::Present) }
}

/// Result from getting the trace log path
#[cfg(feature = "mcp-debug")]
#[derive(Debug, Clone, Serialize, Deserialize, ResultStruct)]
pub struct GetTraceLogPathResult {
    /// Full path to the trace log file
    #[to_metadata]
    log_path:         String,
    /// Whether the log file currently exists
    #[to_metadata]
    exists:           TraceLogFile,
    /// Size of the log file in bytes (if it exists)
    #[to_metadata(skip_if_none)]
    file_size_bytes:  Option<u64>,
    /// Message template for formatting responses
    #[to_message(message_template = "Trace log path: {log_path}")]
    message_template: String,
}
#[cfg(feature = "mcp-debug")]
#[derive(ToolFn)]
#[tool_fn(params = "NoParams", output = "GetTraceLogPathResult")]
pub struct GetTraceLogPath;

#[cfg(feature = "mcp-debug")]
#[allow(
    clippy::unused_async,
    reason = "ToolFn trait requires async handler signature"
)]
async fn handle_impl(_: NoParams) -> Result<GetTraceLogPathResult> {
    // Get the trace log path
    let log_path = TracingLevel::get_trace_log_path();

    // Shadow the PathBuf with the String form needed by the result constructor.
    // The metadata() call below works on the shadow because String: AsRef<Path>.
    let log_path = log_path.to_string_lossy().to_string();

    // Check if the file exists and get its size
    let (exists, file_size_bytes) = std::fs::metadata(&log_path)
        .map_or((TraceLogFile::Missing, None), |metadata| {
            (TraceLogFile::Present, Some(metadata.len()))
        });

    Ok(GetTraceLogPathResult::new(
        log_path,
        exists,
        file_size_bytes,
    ))
}