/// Compaction handler — T3.4 Scheduler
///
/// Endpoint for triggering manual or scheduled compaction.
/// Can be called by CronJob (K8s) or manually via API.

use actix_web::{web, HttpRequest, HttpResponse};
use serde::{Deserialize, Serialize};
use serde_json::json;

use crate::http_server::AppState;
use crate::compaction::{compact_memory, CompactionMode, CompactionStats};

/// Compaction request parameters
#[derive(Debug, Deserialize, Clone)]
pub struct CompactRequest {
    /// Dry-run mode (don't apply changes)
    #[serde(default)]
    pub dry_run: bool,

    /// Enable LLM-based semantic dedup (T3.2)
    #[serde(default = "default_enable_semantic")]
    pub enable_semantic_dedup: bool,

    /// Project filter (if None, all projects)
    pub project: Option<String>,
}

fn default_enable_semantic() -> bool {
    false
}

/// Compaction response
#[derive(Debug, Serialize)]
pub struct CompactResponse {
    pub status: String,
    pub mode: String,
    pub stats: CompactionStats,
}

/// POST /memory/compact - Trigger memory compaction
pub async fn compact_handler(
    req: HttpRequest,
    body: web::Json<CompactRequest>,
    state: web::Data<AppState>,
) -> HttpResponse {
    // 1. Validate JWT + rate limiting (centralized middleware)
    if let Err(response) = crate::handlers::middleware::validate_and_rate_limit(&req, &state, "compact", 10) {
        return response;
    }

    // 2. Execute compaction
    let mode = if body.dry_run {
        CompactionMode::DryRun
    } else {
        CompactionMode::Execute
    };

    match compact_memory_sync(&state, mode).await {
        Ok(stats) => {
            let mode_str = if body.dry_run { "dry-run" } else { "execute" };
            crate::handlers::response_builder::success_response(CompactResponse {
                status: "success".to_string(),
                mode: mode_str.to_string(),
                stats,
            })
        }
        Err(e) => {
            tracing::error!("Compaction failed: {}", e);
            crate::handlers::response_builder::internal_error(
                &format!("Compaction failed: {}", e)
            )
        }
    }
}

/// Execute compaction asynchronously
async fn compact_memory_sync(
    state: &AppState,
    mode: CompactionMode,
) -> anyhow::Result<CompactionStats> {
    crate::compaction::compact_memory(&state.pool, None, mode).await
}

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

    #[test]
    fn test_compact_request_dry_run() {
        let req = CompactRequest {
            dry_run: true,
            enable_semantic_dedup: false,
            project: None,
        };

        assert!(req.dry_run);
        assert!(!req.enable_semantic_dedup);
    }

    #[test]
    fn test_compact_request_with_project() {
        let req = CompactRequest {
            dry_run: false,
            enable_semantic_dedup: true,
            project: Some("poimen".to_string()),
        };

        assert_eq!(req.project, Some("poimen".to_string()));
    }

    #[test]
    fn test_compact_response_serialization() {
        let resp = CompactResponse {
            status: "success".to_string(),
            mode: "execute".to_string(),
            stats: CompactionStats {
                duplicate_edges_deleted: 5,
                stale_facts_deleted: 3,
                ..Default::default()
            },
        };

        let json = serde_json::to_string(&resp).unwrap();
        assert!(json.contains("success"));
        assert!(json.contains("duplicate_edges_deleted"));
    }
}