ex_video_factory

defmodule ExVideoFactory do
  @moduledoc """
  Elixir wrapper for France**Télévisions** Video Factory API.
  """

  require Logger

  @doc """
  Get the list of `videos`.

  ## Options

    * `query`: Map of parameters to filter the query
      - q: query string in title, additional_title, original_title (case insensitive)
      - qid: filter with the video identifier
      - page: page index
      - per_page: number of items per page
      - etc.

  ## Response example
  ```elixir
  %{
    videos: [
      %{
        "id": "978f7146-41e3-11e6-8153-000d3a23d482",
        "created_at": "2015-09-16T10:55:12.200+02:00",
        "updated_at": "2015-09-16T10:55:12.200+02:00",
        "created_by": nil,
        "created_via": "import-plurimedia-epg",

        "title": "Amour, gloire et beauté",
        "additional_title": "La vengeance de Samantha",
        "category": %{
          "id": "series-fictions",
          "label": "séries & fictions"
        },
        ...

        "images": [%{image}, %{image}, ...],

        "licensing": "svod",
        "embeddable": true,
        ...
        "platforms": %{
          "ftv": %{ ... },
          "bouygues": %{ ... },
          "orange": %{ ... },
          ...
        }

        "groups": [
          %{
            "id": "ea2bed61-47e0-4116-bf8c-33c375fd9030",
            "label": "Amour, gloire et beauté - Saison 13",
            ...
            "images": [%{image}, %{image}, ...],
          },
          ...
        ]
      },
      ...
    ],
    size: 10,
    offset: 0,
    total: 16238
  }
  ```

  """
  def videos(query \\ %{}) do
    page =
      Map.get(query, "page", 1)
      |> force_integer

    page_size =
      Map.get(query, "per_page", 20)
      |> force_integer

    query =
      query
      |> format_query

    response = ExVideoFactory.Client.get("videos", query: query)
    case response do
      %HTTPotion.Response{} ->
        total = get_total_number_of_elements(response)
        list = response.body

        %{
          videos: list,
          size: length(list),
          offset: (page - 1) * page_size + 1,
          total: total
        }
      msg ->
        Logger.warn("#{msg}")
        %{
        videos: [],
        size: 0,
        offset: 0,
        total: 0,
      }
    end
  end

  @doc """
  Get the list of `regions`.

  ## Response example
  ```elixir
  %{
    regions: [
      %{
        "id": "saint-pierre-et-miquelon",
        "label": "Saint-Pierre et Miquelon",
        "code": "SPM",
        "time_zone": "America/Miquelon"
      },
      ...
    ],
    size: 10,
    total: 12
  }

  ```

  """
  def regions do
    response = ExVideoFactory.Client.get("regions")
    list = response.body
    total = get_total_number_of_elements(response)

    %{
      regions: list,
      size: length(list),
      total: total
    }
  end

  @doc """
  Get the list of `types`.

  ## Response example
  ```elixir
  %{
    types: [
      %{
        "id": "bande-annonce",
        "label": "Bande-Annonce"
      },
      ...
    ],
    size: 10,
    total: 24
  }

  ```
  """
  def types do
    response = ExVideoFactory.Client.get("types")
    list = response.body
    total = get_total_number_of_elements(response)

    %{
      types: list,
      size: length(list),
      total: total
    }
  end

  @doc """
  Get the list of `channels`.

  ## Response example
  ```elixir
  %{
    "channels": [
      %{
        "id": "saint-pierre-et-miquelon-1ere",
        "label": "Saint-Pierre et Miquelon 1ère",
        "region": %{
            "id": "saint-pierre-et-miquelon",
            "label": "Saint-Pierre et Miquelon"
            "code": "SPM",
            "time_zone": "America/Miquelon"
        },
        "tags": ["outremer"]
      },
      ...
    ],
    "size": 10,
    "total": 30
  }

  ```
  """
  def channels do
    response = ExVideoFactory.Client.get("channels")
    list = response.body
    total = get_total_number_of_elements(response)

    %{
      channels: list,
      size: length(list),
      total: total
    }
  end

  defp get_total_number_of_elements(%HTTPotion.Response{headers: headers}) do
    headers['X-Total-Count']
  end

  defp get_total_number_of_elements(_) do
    0
  end

  defp force_integer(param) when is_bitstring(param) do
    param
    |> String.to_integer()
  end

  defp force_integer(param) do
    param
  end

  @doc false
  def format_query(query) do
    query
    |> Enum.map(fn {key, value} ->
      format_field(key, value)
    end)
    |> Map.new()
  end

  defp format_field(key, value) do
    format_field(key, String.split(key, "_"), value)
  end

  defp format_field(_, [prefix, "after"], value) do
    {prefix <> "_at[gte]", format_iso8601(value)}
  end

  defp format_field(_, [prefix, "before"], value) do
    {prefix <> "_at[lte]", format_iso8601(value)}
  end

  defp format_field("channels", _, value) do
    {"channel.id", Enum.join(value, ",")}
  end

  defp format_field(key, _, value) do
    {key, value}
  end

  defp format_iso8601(date) do
    char = String.at(date, 19)

    case char do
      " " ->
        String.replace(date, ~r/\s/, "+")

      nil ->
        raise ArgumentError, message: "Unsupported date format: " <> date

      _ ->
        date
    end
  end

  @doc """
  Get the list of files information based on `Video` identifier.

  ## Response example
  ```elixir
  [
    {
      "created_at": "2018-05-03T18:29:57+02:00",
      "updated_at": "2018-05-03T18:29:57+02:00",
      "id": "c465b024-75a1-479d-9195-effe90da9cbd",
      "format": {
        "id": "video-mp4",
        "label": "video/mp4",
        "type": "video",
        "mime_type": "video/mp4"
      },
      "storage": "akamai-replay-prod",
      "path": "/streaming-adaptatif_france-dom-tom/2018/S18/J4/",
      "filename": "176668575-5aeb383753763-standard5.mp4",
      "md5_checksum": null,
      "filesize_bytes": 82099370,
      "external_ids": {
        "video_id": "32a2748d-9aa3-430b-9287-fc840f55b012",
        "legacy_id": "176668575",
        "group_id": null,
        "job_id": "2695577",
        "remote_id": null
      },
      "tags": [],
      "created_via": "factory",
      "version": "1525364791000000",
      "bitrate_kbps": 1471,
      "video_tracks": [
      {
        "codec_rfc6381": "avc1.4d001f",
        "bitrate_kbps": 1390,
        "width": 1024,
        "height": 576,
        "frame_rate_fps": 25
      }
      ],
      "audio_tracks": [
      {
        "codec_rfc6381": "mp4a.40.2",
        "bitrate_kbps": 81,
        "sample_rate_hz": 48000,
        "lang": "fra"
      }
      ],
      "text_tracks": [],
      "url": "https://replayftv-vh.akamaihd.net/z/streaming-adaptatif_france-dom-tom/2018/S18/J4/176668575-5aeb383753763-standard5.mp4"
    },
    ...
  ]

  ```
  """
  def get_files_for_video_id(id) do
    query = %{"external_ids.video_id": id, per_page: 1000}

    ExVideoFactory.Client.get("files", query: query).body
  end

  @doc """
  Get the list of files on FTP server based on `Video` identifier.

  ## Response example
  ```elixir
  [
    "/ftp/file/path/quality_1.mp4",
    "/ftp/file/path/quality_2.mp4",
    "/ftp/file/path/quality_3.mp4",
    "/ftp/file/path/quality_4.mp4",
    "/ftp/file/path/quality_5.mp4",
  ]

  ```
  """
  def get_ftp_paths_for_video_id(id) do
    query = %{"external_ids.video_id": id, per_page: 1000}

    ExVideoFactory.Client.get("files", query: query).body
    |> get_files
  end

  @doc """
  Get the list of files on FTP server based on `Video` diffusion identifier.

  ## Response example
  ```elixir
  [
    %{
      format: "hds_akamai",
      urls: []
    },
    %{
      format: "m3u8-download",
      urls: [
        "/ftp/file/path/quality_1.mp4",
        "/ftp/file/path/quality_2.mp4",
        "/ftp/file/path/quality_3.mp4",
        "/ftp/file/path/quality_4.mp4"
      ]
    },
    %{
      format: "hls_v5_os",
      urls: [
        "/ftp/file/path/quality_1.mp4",
        "/ftp/file/path/quality_2.mp4",
        "/ftp/file/path/quality_3.mp4",
        "/ftp/file/path/quality_4.mp4",
        "/ftp/file/path/quality_5.mp4"
      ]
    }
  ]

  ```
  """
  def get_ftp_paths_for_id_diffusion(id_diffusion) do
    query = [idDiffusion: id_diffusion]

    ExVideoFactory.LegacyClient.get("getInfosOeuvre/v2/", query: query).body
    |> get_legacy_files
  end

  @doc """
  Get the list of HTTP URLs for TTML contents based on `Video` identifier.

  ## Response example
  ```elixir
  [
    "https://sample-server.com/some/path/caption.ttml",
  ]

  ```
  """
  def get_http_url_for_ttml(id) do
    query = %{
      "external_ids.video_id": id,
      per_page: 1000,
      "format.id": "caption-ttml"
    }

    ExVideoFactory.Client.get("files", query: query).body
    |> get_urls([])
  end

  @doc false
  def get_files(content) do
    content
    |> format_files([])
  end

  @doc false
  def get_legacy_files(content) do
    content
    |> Map.get("videos")
    |> format_legacy_files([])
  end

  defp format_files([], list), do: list

  defp format_files([item | items], list) do
    list =
      case format_file(item) do
        nil -> list
        filename -> List.insert_at(list, -1, filename)
      end

    format_files(items, list)
  end

  defp format_legacy_files([], list), do: list

  defp format_legacy_files([item | items], list) do
    list =
      case item do
        %{"format" => _format, "url" => nil} ->
          list

        %{"format" => format, "url" => url} ->
          item = %{
            format: format,
            urls: format_url(url)
          }

          List.insert_at(list, -1, item)
      end

    format_legacy_files(items, list)
  end

  defp format_url("http://replayftv-vh.akamaihd.net/i/" <> url) do
    list = String.split(url, ",")

    [base_root, _extension] = Enum.filter(list, fn item -> !is_standard(item) end)

    qualities = Enum.filter(list, fn item -> is_standard(item) end)

    for quality <- qualities do
      "/343079/http/#{base_root}#{quality}.mp4"
    end
  end

  defp format_url(_url) do
    []
  end

  defp is_standard("standard" <> _id), do: true
  defp is_standard(_something), do: false

  defp format_file(%{"format" => %{"id" => id, "mime_type" => mime_type}} = item) do
    case {id, mime_type} do
      {"video-mp4", "video/mp4"} ->
        case Map.get(item, "storage") do
          "akamai-replay-prod" ->
            path = Map.get(item, "path")
            filename = Map.get(item, "filename")
            "/343079/http" <> path <> filename

          _ ->
            nil
        end
      {"manifest-ism", "application/xml"} ->
        case Map.get(item, "storage") do
          "amazon-replay-prod" ->
            path = Map.get(item, "path")
            filename = Map.get(item, "filename")
            path <> filename

          _ ->
            nil
        end
      _ ->
        nil
    end
  end

  defp format_file(_item) do
    nil
  end

  @doc false
  def get_urls([], result), do: result

  def get_urls([item | items], result) do
    result =
      case Map.get(item, "url", nil) do
        nil -> result
        url -> List.insert_at(result, -1, url)
      end

    get_urls(items, result)
  end
end