require "test_helper"

class DocumentChannelTest < ActionCable::Channel::TestCase
  setup do
    @anna = create_user("anna@example.com")
    @bob = create_user("bob@example.com")
    @doc = create_document(@anna)
  end

  def b64(s) = Base64.strict_encode64(s)
  def last = transmissions.last

  test "rejects without access" do
    stub_connection current_user: @bob
    subscribe id: @doc.id
    assert subscription.rejected?
  end

  test "init sends the JSON while there are no updates yet, then the updates" do
    stub_connection current_user: @anna
    subscribe id: @doc.id, key: "a"
    assert subscription.confirmed?
    assert_equal "owner", last["role"].to_s
    assert_equal DOC_JSON, last["content"]
    assert_empty last["updates"]

    @doc.updates.create!(data: "\x01\x02")
    subscribe id: @doc.id, key: "a"
    assert_nil last["content"]
    assert_equal [ b64("\x01\x02") ], last["updates"].map { _1["data"] }
  end

  test "an editor's update is stored and passed on to everyone" do
    stub_connection current_user: @anna
    subscribe id: @doc.id, key: "a"
    assert_broadcasts(DocumentChannel.broadcasting_for(@doc), 1) do
      perform :update, data: b64("abc")
    end
    assert_equal [ "abc" ], @doc.updates.pluck(:data)
  end

  test "a viewer (link) can't change anything but may send awareness" do
    link = @doc.share_links.create!(role: :viewer, created_by: @anna)
    stub_connection current_user: nil
    subscribe id: @doc.id, token: link.token, key: "v"
    assert subscription.confirmed?
    perform :update, data: b64("x")
    perform :compact, state: b64("x"), ids: [], snapshot: DOC_JSON
    assert_equal 0, @doc.updates.count
    assert_broadcasts(DocumentChannel.broadcasting_for(@doc), 1) do
      perform :awareness, data: b64("cursor")
    end
  end

  test "compact replaces the listed updates by one state and stores the snapshot" do
    a = @doc.updates.create!(data: "1")
    b = @doc.updates.create!(data: "2")
    keep = @doc.updates.create!(data: "3")
    stub_connection current_user: @anna
    subscribe id: @doc.id, key: "a"
    snapshot = { version: 2, sheets: [ { id: "s9", name: "Neu", objects: [] } ] }.to_json
    perform :compact, state: b64("12"), ids: [ a.id, b.id ], snapshot: snapshot
    assert_equal %w[3 12], @doc.updates.order(:id).pluck(:data)
    assert keep.reload
    assert_equal snapshot, @doc.reload.content
  end

  test "invalid snapshots are ignored" do
    stub_connection current_user: @anna
    subscribe id: @doc.id, key: "a"
    perform :snapshot, content: "[1]"
    assert_equal DOC_JSON, @doc.reload.content
  end

  test "losing access mid-session" do
    DocumentMembership.grant!(document: @doc, user: @bob, role: :editor, source: :invite)
    stub_connection current_user: @bob
    subscribe id: @doc.id, key: "b"
    @doc.document_memberships.delete_all
    subscription.send(:revalidate)
    assert_equal "revoked", last["type"]
    perform :update, data: b64("late")
    assert_equal 0, @doc.updates.count
  end

  test "role change is announced" do
    DocumentMembership.grant!(document: @doc, user: @bob, role: :editor, source: :invite)
    stub_connection current_user: @bob
    subscribe id: @doc.id, key: "b"
    @doc.document_memberships.update_all(role: DocumentMembership.roles[:viewer])
    subscription.send(:revalidate)
    assert_equal({ "type" => "role", "role" => "viewer" }, last.slice("type", "role").transform_values(&:to_s))
  end
end