defmodule StepFlow.NotificationHooks.NotificationHookManager do
  @moduledoc """
  Notification manager context.

  """

  alias StepFlow.Jobs
  alias StepFlow.NotificationHooks.NotificationEndpoints
  alias StepFlow.NotificationHooks.NotificationTemplates
  alias StepFlow.Workflows

  require Logger

  def get_last_status(workflow_notification_data) do
    if StepFlow.Map.get_by_key_or_atom(workflow_notification_data, "status") == nil do
      []
    else
      StepFlow.Map.get_by_key_or_atom(workflow_notification_data, "status")
    end
  end

  def notification_slack_from_job(job, channel, exposed_domain_name, description) do
    send(
      :step_flow_slack_bot,
      {:message,
       "Error for job #{job.name} ##{job.id} <#{exposed_domain_name}/workflows/#{job.workflow_id} |Open Workflow>\n```#{description}```",
       channel}
    )
  end

  def notification_teams_from_job(job, url, workflow, exposed_domain_name, description) do
    headers = [{"content-type", "application/json"}]

    body =
      Poison.encode!(%{
        "@context": "https://schema.org/extensions",
        "@type": "MessageCard",
        potentialAction: [
          %{
            "@type": "OpenUri",
            name: "View Workflow",
            targets: [
              %{
                os: "default",
                uri: "#{exposed_domain_name}/workflows/#{job.workflow_id}"
              }
            ]
          }
        ],
        sections: [
          %{
            facts: [
              %{
                name: "Posted By:",
                value: "#{exposed_domain_name}"
              },
              %{
                name: "Workflow Reference:",
                value: "#{workflow.reference}"
              },
              %{
                name: "Workflow ID:",
                value: "#{workflow.id}"
              },
              %{
                name: "Workflow Identifier:",
                value: "#{workflow.identifier}"
              },
              %{
                name: "Job ID:",
                value: "#{job.id}"
              },
              %{
                name: "Job:",
                value: "#{job.name}"
              }
            ],
            text: "```#{description}```"
          }
        ],
        summary: "MCAI Workflow Error Notification",
        themeColor: "FF5733",
        title: "MCAI Workflow Error Notification"
      })

    Logger.debug(
      "#{__MODULE__}: POST #{url}, headers: #{inspect(headers)}, body: #{inspect(body)}"
    )

    case HTTPoison.post(url, body, headers) do
      {:ok, %{body: body, headers: _, request: _, request_url: _, status_code: 200}} ->
        {:ok, body}

      {:ok, response} ->
        Logger.error("Unable to notify: #{inspect(response)}")

      {:error, error} ->
        Logger.error("Unable to notify: #{inspect(error)}")
    end
  end

  def notification_from_job(job_id, description \\ nil) do
    job = Jobs.get_job!(job_id)
    topic = "update_workflow_" <> Integer.to_string(job.workflow_id)
    channel = StepFlow.Configuration.get_slack_channel()
    workflow = Workflows.get_workflow!(job.workflow_id)
    exposed_domain_name = StepFlow.Configuration.get_exposed_domain_name()

    slack_token = StepFlow.Configuration.get_slack_token()

    if !(blank?(slack_token) or blank?(description) or blank?(channel)) do
      notification_slack_from_job(job, channel, exposed_domain_name, description)
    end

    teams_url = StepFlow.Configuration.get_teams_url()

    if !(blank?(teams_url) or blank?(description)) do
      notification_teams_from_job(job, teams_url, workflow, exposed_domain_name, description)
    end

    StepFlow.Notification.send(topic, %{workflow_id: job.workflow_id})
  end

  def notify_endpoint_with_status(
        workflow_notification_url,
        job,
        workflow,
        exposed_domain_name,
        status,
        notification_template_name,
        workflow_endpoint_credentials
      )
      when is_binary(notification_template_name) do
    case NotificationTemplates.get_notification_template_by_name(notification_template_name) do
      nil ->
        Logger.error("#{__MODULE__}: There is no notification template under that name")
        {:error, "There is no notification template under that name."}

      notification_template ->
        notify_endpoint_with_status(
          workflow_notification_url,
          job,
          workflow,
          exposed_domain_name,
          status,
          notification_template,
          workflow_endpoint_credentials
        )
    end
  end

  def notify_endpoint_with_status(
        workflow_notification_url,
        job,
        workflow,
        exposed_domain_name,
        status,
        notification_template,
        workflow_endpoint_credentials
      ) do
    case JSON.decode(notification_template.template_headers) do
      {:error, err} ->
        Logger.error("#{__MODULE__}: #{inspect(err)}")
        {:error, "Couldn't parse the provided template headers."}

      {:ok, json_headers} ->
        fill_notification_template_body(
          workflow_notification_url,
          job,
          workflow,
          exposed_domain_name,
          json_headers
          |> Enum.map(fn elem -> Map.to_list(elem) end)
          |> Enum.concat(),
          status,
          notification_template,
          workflow_endpoint_credentials
        )
    end
  end

  defp fill_notification_template_body(
         workflow_notification_url,
         job,
         workflow,
         exposed_domain_name,
         headers,
         status,
         notification_template,
         workflow_endpoint_credentials
       ) do
    accepted_parameters = %{
      # Replacement for ternary operator
      "exposed_domain_name" => (is_nil(exposed_domain_name) && "") || exposed_domain_name,
      "workflow.id" => Integer.to_string(workflow.id),
      "workflow.reference" => workflow.reference,
      "workflow.identifier" => workflow.identifier,
      "job.name" => (is_nil(job) && "") || job.name,
      "job.id" => (is_nil(job) && "") || Integer.to_string(job.id),
      "status" => status
    }

    case intern_template_process(notification_template.template_body, accepted_parameters) do
      {:error, message} ->
        {:error, message}

      {:ok, template} ->
        send_notification(
          workflow_notification_url,
          template,
          headers,
          job,
          accepted_parameters,
          workflow_endpoint_credentials
        )
    end
  end

  defp send_notification(
         workflow_notification_url,
         template_body_string,
         headers,
         job,
         accepted_parameters,
         workflow_endpoint_credentials
       ) do
    body =
      case JSON.decode(template_body_string) do
        {:error, err} ->
          Logger.error("#{__MODULE__}: #{inspect(err)}")
          {:error, "Couldn't parse the provided template body."}

        {:ok, json_body} ->
          json_body
          |> JSON.encode!()
      end

    options =
      if workflow_endpoint_credentials != nil do
        [username, password] = String.split(workflow_endpoint_credentials, ":", trim: true)
        [hackney: [basic_auth: {username, password}]]
      else
        []
      end

    Logger.debug(
      "#{__MODULE__}: POST #{workflow_notification_url}, headers: #{inspect(headers)}, body: #{inspect(body)}"
    )

    case HTTPoison.post(workflow_notification_url, body, headers, options) do
      {:error, err} ->
        Logger.error("#{__MODULE__}: #{inspect(err)}")
        {:error, "Couldn't post the notification with the provided notification template."}

      {:ok, response} ->
        if Map.has_key?(response, :status_code) do
          condition =
            if job do
              "job_" <>
                accepted_parameters["status"] <>
                "_" <> Integer.to_string(job.id)
            else
              "workflow_" <> accepted_parameters["status"]
            end

          {
            :ok,
            %{
              "condition" => condition,
              "timestamp" =>
                NaiveDateTime.utc_now()
                |> NaiveDateTime.to_string()
                |> NaiveDateTime.from_iso8601!()
                |> NaiveDateTime.truncate(:second),
              "response" => response.status_code
            }
          }
        else
          {:error, "The associated URL didn't reply when queried."}
        end
    end
  end

  def retrieve_status(
        notification_endpoint,
        _conditions,
        _conditions_with_templates,
        _status,
        _workflow_notification_data,
        _job,
        _workflow,
        _exposed_domain_name
      )
      when is_nil(notification_endpoint) do
    Logger.error("#{__MODULE__}: no endpoints were defined.")
    nil
  end

  def retrieve_status(
        notification_endpoint,
        conditions,
        conditions_with_templates,
        status,
        workflow_notification_data,
        job,
        workflow,
        exposed_domain_name
      )
      when status in ["error", "completed"] and job != nil do
    cond do
      Enum.member?(
        conditions,
        "job_completed"
      ) and status == "completed" ->
        notify_endpoint(
          notification_endpoint,
          job,
          workflow,
          exposed_domain_name,
          status,
          conditions_with_templates["job_completed"],
          retrieve_credentials(workflow_notification_data, notification_endpoint)
        )

      Enum.member?(
        conditions,
        "job_error"
      ) and status == "error" ->
        notify_endpoint(
          notification_endpoint,
          job,
          workflow,
          exposed_domain_name,
          status,
          conditions_with_templates["job_error"],
          retrieve_credentials(workflow_notification_data, notification_endpoint)
        )

      true ->
        nil
    end
  end

  def retrieve_status(
        notification_endpoint,
        conditions,
        conditions_with_templates,
        status,
        workflow_notification_data,
        nil,
        workflow,
        exposed_domain_name
      )
      when status in ["error", "completed"] do
    cond do
      Enum.member?(
        conditions,
        "workflow_completed"
      ) and status == "completed" ->
        notify_endpoint(
          notification_endpoint,
          nil,
          workflow,
          exposed_domain_name,
          status,
          conditions_with_templates["workflow_completed"],
          retrieve_credentials(workflow_notification_data, notification_endpoint)
        )

      Enum.member?(
        conditions,
        "workflow_error"
      ) and status == "error" ->
        notify_endpoint(
          notification_endpoint,
          nil,
          workflow,
          exposed_domain_name,
          status,
          conditions_with_templates["workflow_error"],
          retrieve_credentials(workflow_notification_data, notification_endpoint)
        )

      true ->
        nil
    end
  end

  def retrieve_status(
        _notification_endpoint,
        _conditions,
        _conditions_with_templates,
        status,
        _workflow_notification_data,
        _job,
        _workflow,
        _exposed_domain_name
      )
      when status not in ["error", "completed"],
      do: nil

  defp notify_endpoint(
         notification_endpoint,
         job,
         workflow,
         exposed_domain_name,
         status,
         conditions_with_templates,
         credentials
       ) do
    case notification_endpoint
         |> StepFlow.Map.get_by_key_or_atom("endpoint_url", "")
         |> notify_endpoint_with_status(
           job,
           workflow,
           exposed_domain_name,
           status,
           conditions_with_templates,
           credentials
         ) do
      {:error, message} ->
        Logger.error("#{__MODULE__}: #{message}")
        nil

      {:ok, payload} ->
        payload
    end
  end

  def manage_notification_status(workflow_id, job, status) do
    workflow = Workflows.get_workflow!(workflow_id)

    exposed_domain_name = StepFlow.Configuration.get_exposed_domain_name()

    workflow_notifications_with_status =
      for workflow_notification_data <- workflow.notification_hooks do
        conditions_with_templates =
          StepFlow.Map.get_by_key_or_atom(workflow_notification_data, "conditions")

        last_status = get_last_status(workflow_notification_data)
        endpoint_key = StepFlow.Map.get_by_key_or_atom(workflow_notification_data, "endpoint")

        case {NotificationEndpoints.get_notification_endpoint_by_placeholder(endpoint_key),
              is_map(conditions_with_templates)} do
          {notification_endpoint, true} ->
            conditions =
              conditions_with_templates
              |> Map.keys()

            new_status =
              retrieve_status(
                notification_endpoint,
                conditions,
                conditions_with_templates,
                status,
                workflow_notification_data,
                job,
                workflow,
                exposed_domain_name
              )

            if new_status != nil do
              Map.put(workflow_notification_data, "status", last_status ++ [new_status])
            else
              workflow_notification_data
            end

          {nil, _} ->
            Logger.error("Could not find an url for template endpoint key #{endpoint_key}")

          {_, false} ->
            Logger.error("Condition templates is not a map!")
        end
      end

    {_, workflow} =
      Workflows.update_workflow(workflow, %{
        notification_hooks: workflow_notifications_with_status
      })

    workflow
  end

  defp retrieve_credentials(notification_data, notification_endpoint) do
    notification_endpoint_credentials =
      StepFlow.Map.get_by_key_or_atom(notification_endpoint, "endpoint_credentials")

    cond do
      !blank?(notification_endpoint_credentials) ->
        notification_endpoint_credentials

      !blank?(
        notification_data_credentials =
            StepFlow.Map.get_by_key_or_atom(notification_data, "credentials")
      ) ->
        notification_data_credentials

      true ->
        nil
    end
  end

  defp intern_template_process(template, accepted_parameters) do
    accepted_parameters
    |> Map.to_list()
    |> replace(template)
    |> check_remaining_to_template()
  end

  defp replace([], template), do: template

  defp replace([{key, value} | keys], template) do
    template =
      String.replace(
        template,
        "#" <> key <> "#",
        value
      )

    replace(keys, template)
  end

  defp check_remaining_to_template(template) do
    case Regex.scan(~r/#(?:[[:word:]][._()-]?)*#/, template) do
      [] ->
        {:ok, template}

      array ->
        message = "Following parameters are not availables : #{inspect(array)}.
        Please check the documentation for a list of available parameters."
        Logger.error(message)
        {:error, message}
    end
  end

  defp blank?(path),
    do: "" == path |> to_string() |> String.trim()
end