// telemetry.go — REST-чтение телеметрии из per-tenant PostgreSQL.
//
// Endpoint: GET /v1/namespaces/{ns}/iot/telemetry?device_id={id}&limit={n}
package handler

import (
	"net/http"
	"strconv"

	"gitea.services.ngcloud.ru/Nail/IoT/internal/storage/iotpg"
)

// ListIoTTelemetry — GET /v1/namespaces/{ns}/iot/telemetry.
func (h *Handler) ListIoTTelemetry(w http.ResponseWriter, r *http.Request) {
	if h.IoTPG == nil {
		writeJSON(w, http.StatusServiceUnavailable, errResp("IoT telemetry storage not configured"))
		return
	}

	ns := pathVar(r, "namespace")
	deviceID := r.URL.Query().Get("device_id")
	limit := 50
	if ls := r.URL.Query().Get("limit"); ls != "" {
		if n, err := strconv.Atoi(ls); err == nil && n > 0 {
			limit = n
		}
	}
	offset := 0
	if os := r.URL.Query().Get("offset"); os != "" {
		if n, err := strconv.Atoi(os); err == nil && n >= 0 {
			offset = n
		}
	}

	rows, err := h.IoTPG.QueryTelemetry(r.Context(), ns, deviceID, limit, offset)
	if err != nil {
		h.Log.Error("query IoT telemetry", "namespace", ns, "device", deviceID, "err", err)
		writeJSON(w, http.StatusInternalServerError, errResp("failed to query telemetry"))
		return
	}
	if rows == nil {
		rows = []iotpg.TelemetryRow{}
	}

	writeJSON(w, http.StatusOK, map[string]any{
		"items": rows,
		"count": len(rows),
	})
}