Class ActiveStorage::Service::AzureStorageService < ActiveStorage::Service

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 13
def initialize(storage_account_name:, storage_access_key:, container:)
  @client = Azure::Storage::Client.create(storage_account_name: storage_account_name, storage_access_key: storage_access_key)
  @signer = Azure::Storage::Core::Auth::SharedAccessSignature.new(storage_account_name, storage_access_key)
  @blobs = client.blob_client
  @container = container
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 125
def blob_for(key)
  blobs.get_blob_properties(container, key)
rescue Azure::Core::Http::HTTPError
  false
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 50
def delete(key)
  instrument :delete, key: key do
    begin
      blobs.delete_blob(container, key)
    rescue Azure::Core::Http::HTTPError
      # Ignore files already deleted
    end
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 60
  def delete_prefixed(prefix)
    instrument :delete_prefixed, prefix: prefix do
      marker = nil

      loop do
        results = blobs.list_blobs(container, prefix: prefix, marker: marker)

        results.each do |blob|
          blobs.delete_blob(container, blob.name)
        end

        break unless marker = results.continuation_token.presence
      end
    end
  end

  def exist?(key)
    instrument :exist, key: key do |payload|
      answer = blob_for(key).present?
      payload[:exist] = answer
      answer
    end
  end

  def url(key, expires_in:, filename:, disposition:, content_type:)
    instrument :url, key: key do |payload|
      generated_url = signer.signed_uri(
        uri_for(key), false,
        service: "b",
        permissions: "r",
        expiry: format_expiry(expires_in),
        content_disposition: content_disposition_with(type: disposition, filename: filename),
        content_type: content_type
      ).to_s

      payload[:url] = generated_url

      generated_url
    end
  end

  def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
    instrument :url, key: key do |payload|
      generated_url = signer.signed_uri(
        uri_for(key), false,
        service: "b",
        permissions: "rw",
        expiry: format_expiry(expires_in)
      ).to_s

      payload[:url] = generated_url

      generated_url
    end
  end

  def headers_for_direct_upload(key, content_type:, checksum:, **)
    { "Content-Type" => content_type, "Content-MD5" => checksum, "x-ms-blob-type" => "BlockBlob" }
  end

  private
    def uri_for(key)
      blobs.generate_uri("#{container}/#{key}")
    end

    def blob_for(key)
      blobs.get_blob_properties(container, key)
    rescue Azure::Core::Http::HTTPError
      false
    end

    def format_expiry(expires_in)
      expires_in ? Time.now.utc.advance(seconds: expires_in).iso8601 : nil
    end

    # Reads the object for the given key in chunks, yielding each to the block.
    def stream(key)
      blob = blob_for(key)

      chunk_size = 5.megabytes
      offset = 0

      while offset < blob.properties[:content_length]
        _, chunk = blobs.get_blob(container, key, start_range: offset, end_range: offset + chunk_size - 1)
        yield chunk.force_encoding(Encoding::BINARY)
        offset += chunk_size
      end
    end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 30
def download(key, &block)
  if block_given?
    instrument :streaming_download, key: key do
      stream(key, &block)
    end
  else
    instrument :download, key: key do
      _, io = blobs.get_blob(container, key)
      io.force_encoding(Encoding::BINARY)
    end
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 43
def download_chunk(key, range)
  instrument :download_chunk, key: key, range: range do
    _, io = blobs.get_blob(container, key, start_range: range.begin, end_range: range.exclude_end? ? range.end - 1 : range.end)
    io.force_encoding(Encoding::BINARY)
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 76
def exist?(key)
  instrument :exist, key: key do |payload|
    answer = blob_for(key).present?
    payload[:exist] = answer
    answer
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 131
def format_expiry(expires_in)
  expires_in ? Time.now.utc.advance(seconds: expires_in).iso8601 : nil
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 116
def headers_for_direct_upload(key, content_type:, checksum:, **)
  { "Content-Type" => content_type, "Content-MD5" => checksum, "x-ms-blob-type" => "BlockBlob" }
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 136
def stream(key)
  blob = blob_for(key)

  chunk_size = 5.megabytes
  offset = 0

  while offset < blob.properties[:content_length]
    _, chunk = blobs.get_blob(container, key, start_range: offset, end_range: offset + chunk_size - 1)
    yield chunk.force_encoding(Encoding::BINARY)
    offset += chunk_size
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 20
def upload(key, io, checksum: nil)
  instrument :upload, key: key, checksum: checksum do
    begin
      blobs.create_block_blob(container, key, IO.try_convert(io) || io, content_md5: checksum)
    rescue Azure::Core::Http::HTTPError
      raise ActiveStorage::IntegrityError
    end
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 121
def uri_for(key)
  blobs.generate_uri("#{container}/#{key}")
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 84
def url(key, expires_in:, filename:, disposition:, content_type:)
  instrument :url, key: key do |payload|
    generated_url = signer.signed_uri(
      uri_for(key), false,
      service: "b",
      permissions: "r",
      expiry: format_expiry(expires_in),
      content_disposition: content_disposition_with(type: disposition, filename: filename),
      content_type: content_type
    ).to_s

    payload[:url] = generated_url

    generated_url
  end
end

# File activestorage/lib/active_storage/service/azure_storage_service.rb, line 101
def url_for_direct_upload(key, expires_in:, content_type:, content_length:, checksum:)
  instrument :url, key: key do |payload|
    generated_url = signer.signed_uri(
      uri_for(key), false,
      service: "b",
      permissions: "rw",
      expiry: format_expiry(expires_in)
    ).to_s

    payload[:url] = generated_url

    generated_url
  end
end