{:ok, _} = Application.ensure_all_started(:supavisor)

# Written by the mesh (modules/supabase). Per-machine values come from settings.json (the module's
# one merge:json file); secrets come from the environment the image reads.
settings = "/etc/pooler/settings.json" |> File.read!() |> Jason.decode!() |> Map.get("pooler", %{})

{:ok, version} =
  case Supavisor.Repo.query!("select version()") do
    %{rows: [[ver]]} -> Supavisor.Helpers.parse_pg_version(ver)
    _ -> nil
  end

params = %{
  "external_id" => to_string(settings["tenant"] || "default"),
  "db_host" => "supabase-db",
  "db_port" => System.get_env("POSTGRES_PORT"),
  "db_database" => System.get_env("POSTGRES_DB"),
  "require_user" => false,
  "auth_query" => "SELECT * FROM pgbouncer.get_auth($1)",
  "default_max_clients" => settings["max-client-connections"] || 100,
  "default_pool_size" => settings["pool-size"] || 20,
  "default_parameter_status" => %{"server_version" => version},
  "users" => [%{
    "db_user" => "pgbouncer",
    "db_password" => System.get_env("POSTGRES_PASSWORD"),
    "mode_type" => System.get_env("POOLER_POOL_MODE"),
    "pool_size" => settings["pool-size"] || 20,
    "is_manager" => true
  }]
}

case Supavisor.Tenants.get_tenant_by_external_id(params["external_id"]) do
  nil ->
    {:ok, _} = Supavisor.Tenants.create_tenant(params)

  # A tenant made elsewhere (HAL named the database host "db") is pointed at this module's
  # database container; nothing else it holds is changed.
  %{db_host: host} = tenant when host != "supabase-db" ->
    {:ok, _} = Supavisor.Tenants.update_tenant(tenant, %{"db_host" => "supabase-db"})

  _ ->
    :ok
end