defmodule SyntropyWeb.Api.ClusterJSON do
  @moduledoc false

  @spec report(map()) :: map()
  def report(cluster_report) do
    %{
      status: cluster_report.status,
      local_node_id: cluster_report.local_node_id,
      local_node_name: cluster_report.local_node_name,
      expected_peers: cluster_report.expected_peers,
      connected_peers: cluster_report.connected_peers,
      unavailable_nodes: Enum.map(cluster_report.unavailable_nodes, &unavailable_node/1),
      abandoned_task_incidents:
        Enum.map(cluster_report.abandoned_task_incidents, &abandoned_task_incident/1),
      nodes: Enum.map(cluster_report.nodes, &cluster_node/1)
    }
  end

  defp cluster_node(node_export) do
    %{
      node_id: node_export.node_id,
      node_name: node_export.node_name,
      services: node_export.services,
      active_tasks: Enum.map(node_export.active_tasks, &active_task/1)
    }
  end

  defp active_task(task) do
    %{
      task_id: task.task_id,
      coordinator_node_id: task.coordinator_node_id,
      started_at: maybe_iso8601(task.started_at),
      selected_agents: task.selected_agents
    }
  end

  defp unavailable_node(node) do
    %{
      node_id: node.node_id,
      node_name: node.node_name,
      status: node.status,
      reason: node.reason,
      last_seen_at: maybe_iso8601(node.last_seen_at),
      lost_at: maybe_iso8601(node.lost_at)
    }
  end

  defp abandoned_task_incident(incident) do
    %{
      task_id: incident.task_id,
      node_id: incident.node_id,
      node_name: incident.node_name,
      coordinator_node_id: incident.coordinator_node_id,
      started_at: maybe_iso8601(incident.started_at),
      last_seen_at: maybe_iso8601(incident.last_seen_at),
      lost_at: maybe_iso8601(incident.lost_at),
      selected_agents: incident.selected_agents
    }
  end

  defp maybe_iso8601(nil), do: nil
  defp maybe_iso8601(%DateTime{} = value), do: DateTime.to_iso8601(value)
end