"""CAN bus frame API routes."""

from flask import Blueprint, jsonify, request, Response


def create_can_blueprint(server_config):
    """
    Create the CAN bus API blueprint.

    Args:
        server_config: Dict with keys:
            - get_can_store: Callable returning CanStore instance
            - require_api_auth: Auth decorator
    """
    bp = Blueprint("api_can", __name__, url_prefix="/api/can")

    get_can_store = server_config["get_can_store"]
    require_api_auth = server_config["require_api_auth"]

    @bp.route("/frames", methods=["GET"])
    @require_api_auth
    def get_frames():
        """List CAN frames with optional filters."""
        store = get_can_store()
        if not store:
            return jsonify({"error": "CAN store not available"}), 503

        device_id = request.args.get("device_id")
        can_id_str = request.args.get("can_id")
        limit = request.args.get("limit", 100, type=int)
        offset = request.args.get("offset", 0, type=int)

        # Clamp
        limit = max(1, min(limit, 1000))
        offset = max(0, offset)

        can_id = None
        if can_id_str:
            try:
                can_id = int(can_id_str, 16) if can_id_str.startswith("0x") else int(can_id_str)
            except ValueError:
                return jsonify({"error": "Invalid can_id format"}), 400

        frames = store.get_frames(device_id=device_id, can_id=can_id,
                                  limit=limit, offset=offset)
        return jsonify({
            "frames": frames,
            "count": len(frames),
            "offset": offset,
            "limit": limit,
        })

    @bp.route("/stats", methods=["GET"])
    @require_api_auth
    def get_stats():
        """Get CAN frame statistics."""
        store = get_can_store()
        if not store:
            return jsonify({"error": "CAN store not available"}), 503

        device_id = request.args.get("device_id")
        return jsonify(store.get_stats(device_id=device_id))

    @bp.route("/frames/export", methods=["GET"])
    @require_api_auth
    def export_csv():
        """Export CAN frames as CSV."""
        store = get_can_store()
        if not store:
            return jsonify({"error": "CAN store not available"}), 503

        device_id = request.args.get("device_id")
        csv_data = store.export_csv(device_id=device_id)

        return Response(
            csv_data,
            mimetype="text/csv",
            headers={"Content-Disposition": "attachment; filename=can_frames.csv"},
        )

    return bp