"""
System logs endpoint — exposes structured log events stored in system_logs table.
"""
from fastapi import APIRouter
from typing import Optional

router = APIRouter(prefix="/api/logs", tags=["logs"])


@router.get("")
def get_logs(
    level: Optional[str] = None,
    source: Optional[str] = None,
    cycle_id: Optional[str] = None,
    ticker: Optional[str] = None,
    date_from: Optional[str] = None,
    date_to: Optional[str] = None,
    limit: int = 300,
):
    """
    Query system logs with optional filters.
    - level: INFO | WARNING | ERROR | CRITICAL
    - source: logger name substring (e.g. 'auto_cycle', 'iv_engine')
    - cycle_id: exact run_id UUID
    - ticker: exact ticker symbol
    - date_from / date_to: ISO date strings YYYY-MM-DD
    - limit: max rows returned (default 300, max 1000)
    """
    from services.database import get_system_logs
    limit = min(limit, 1000)
    logs = get_system_logs(
        level=level,
        source=source,
        cycle_id=cycle_id,
        ticker=ticker,
        date_from=date_from,
        date_to=date_to,
        limit=limit,
    )
    return {"logs": logs, "count": len(logs)}


@router.get("/sources")
def get_log_sources():
    """List distinct source names present in system_logs (for filter dropdown)."""
    from services.database import get_conn
    conn = get_conn()
    rows = conn.execute(
        "SELECT DISTINCT source FROM system_logs WHERE source IS NOT NULL ORDER BY source"
    ).fetchall()
    conn.close()
    return {"sources": [r["source"] for r in rows]}


@router.get("/cycles")
def get_log_cycles(limit: int = 50):
    """List distinct cycle_ids (most recent first) for filter dropdown."""
    from services.database import get_conn
    conn = get_conn()
    rows = conn.execute(
        """SELECT DISTINCT cycle_id, MIN(ts) as first_ts
           FROM system_logs WHERE cycle_id IS NOT NULL
           GROUP BY cycle_id ORDER BY first_ts DESC LIMIT ?""",
        (limit,)
    ).fetchall()
    conn.close()
    return {"cycles": [{"cycle_id": r["cycle_id"], "first_ts": r["first_ts"]} for r in rows]}


@router.delete("/clear")
def clear_old_logs(older_than_days: int = 30):
    """Delete logs older than N days."""
    from services.database import clear_system_logs
    deleted = clear_system_logs(older_than_days)
    return {"deleted": deleted, "older_than_days": older_than_days}


@router.delete("/purge-all")
def purge_all_logs():
    """Truncate the entire system_logs table."""
    from services.database import get_conn
    conn = get_conn()
    conn.execute("DELETE FROM system_logs")
    deleted = conn.total_changes
    conn.commit()
    conn.close()
    return {"deleted": deleted}